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#1
01-30-2007, 12:22 AM
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3.5mph: J-Rho's SM Build
3.5 miles an hour isn't that fast. For most people, it's just a brisk walk. For 2007, with a whole lot of effort, determination, and maybe a little luck, I just might speed up those 3.5 mph.
When people think of an STS car, they picture an econobox, screeching around on skinny street tires, open diffs struggling to put down feeble power. Ken Motonishi winning the 2003 Solo Nationals in STS in a Civic I built over just a couple months  Yours truly in a run at the 2006 Pro Finale, winning class by over 1.2 seconds, 4th PAX for the event, the culmination of my 2006 efforts  When they think of an SM car, they picture a race-bred chassis, huge race slicks sticking out the fenders, and 500hp fireballs shooting from the exhaust pipes. Vic Sias, multi-time SM National Champ  Bob Tunnell, 2006 SM Champion, winner of countless other autocross and roadracing titles  It might be surprising then, that if you lined up ghosts of a top STS car and a top SM car on course, the SM car, for all its power, grip, and hardcore race-preparedness, only walks away from the STS car, albeit at a brisk 3.5mph, on an average speed course. I know this, having data-logged most of the 2006 season in my STS car; by figuring out the lengths of the course with my GPS-based DL1 datalogger, I compute my average speed on course (from the upper 30's to mid 40's) and from time differentials, determine the average speed for other classes, including SM and SM2. 2006 and 2004 SM2 National Champion, Andy McKee  So, then, my goal for 2007 is to make my 240sx at least 3.5mph faster than it was in 2006, while keeping within the SCCA's Street Modified ruleset. This 3.5mph is actually what I've found to be the average speed difference between STS and the Street Modified 2 class (SM2), which is my real target, for reasons I'll discuss later. Multi-time National Champ, 2nd in 2006 by .1 seconds, Erik Strelneiks in his 3-rotor'd FD  The starting point for this effort is the 1992 hatchback I managed to bring home the 2006 STS jacket in. Its build is detailed here. By the end of the season, the car was pretty well dialed in and close to max'd out within the STS ruleset. Put differently, there isn't going to be much speed found in STS allowances not yet utilized. The speed has to be found through the new stuff I can do in SM. Below I've broken up my plan of attack by component- Engine SM rules changed in 2007 to a sliding scale (1800lbs. + 200lbs/liter) from the previous 3-category weight-break system. My first thought was for a high-compression and cam'd VQ30 mated to the CVT available in the JDM-only Cedric and Gloria, with a super-dooper short rear gear. The car could compete at 2400lbs. and would have pretty huge thrust everywhere on course. The problem is that like most people, my resources (time, money, skills) are finite. Importing one of those trannies, getting its special fluid, trying to program its controls, etc., is likely outside my capabilities. In addition, such a setup, while ideal for autocross once perfected, would render the car useless to other endeavors, like a track day or newbie hack drifting. The objective with a SM motor is to propel the car with enough thrust (torque x gearing) to spin the tires at any speed between about 30 and 70mph, without shifting. Based on tire height, gearing, the 240's static weight distribution, and the grip available from modern DOT tires, that means having over 300ft-lbs. across as many RPM as possible on a dyno. With stock SR/KA 2nd gear, rear end, and 25.5" tall tires, that means ~3000-7250rpm. The most competitive RWD SM cars are in the 2600lb. and under range, so to stay there I need to have an effective displacement of 4.0 liters or less, and I have to use a Nissan/Infiniti block. NA, that means using something like the truck VQ40, or a stroked VQ35. Turbo, that means staying at 2.6 liters or under, since the new rules count FI as a 1.4 liter adder to your displacement for the weight multiplier. So some pros/cons of different options- Stroked VQ35/VQ40: Pros: Light weight Modern design NA = ideal throttle response Cons: Fitment questionable Cost to build to HP goals Powerband - probably not enough displacement to produce adequate breadth of torque curve RB26DET: Pros: Huge power potential, will easily meet torque goals Easy to implement, internals support power levels, turbo'd from factory Cons: Much heavier than other options, with weight in worse possible spot Expensive Rare/hard to get parts for SR20DET: Pros: Readily available Setups are well-known and available, lots of aftermarket support Light weight Cons: Lack of displacement makes torque goals difficult/impossible As with RB26, Non-US origin might make finding some replacement parts difficult KA24DET Pros: Already have a fresh one in the car from STS build Displacement should almost be enough to meet torque goals More available cheap if it blows up Cons: Aftermarket support still in early stages Heavier than SR20 or VQ options Non-turbo from factory means difficulty in proper turbo execution Based on the above, I have decided, at least initially, to turbo the KA. In planning, it worked out well for a few reasons - first, I already had a <1000 mile .020" over freshly rebuilt one sitting in the car. Second, I have a spare KA longblock sitting on an engine stand that is a perfect candidate for a proper race-rebuild. Lastly, with a turbo KA, the car would have a minimum weight of 2560, which I believe I could get my hatchback down to in SM trim. The S13 hatchback does have a couple advantages over the coupe - one, it already has ABS installed and functional, which I really need, and would be a PITA to swap. Two, the extra weight the hatchback carries is already over the rear wheels, right where you'd want it. It is disadvantaged in that it's not as stiff a chassis as the coupe, and is of course a bit heavier, if the car is not already at minimum weight. So KA it is, for 2007 anyway. I haven't gotten too far yet, but here's where it is today:  Turbo System This one is a bit new to me, having never built or autocrossed a turbo car before. I try to make informed decisions so I bought a couple books, and read enough posts and looked at enough dyno charts on enough different forums, I felt I could probably write a book of my own. At some point a few months ago, I had decided that a Garrett GT2871R would be the way to go, and that I only had to make the choice between the .64 and .86 turbine A/R, with the smaller being better for the low-speed corners, and the larger being more fun in the high-rpm stuff. In Street Modified I could switch from the only DOT-approved fuel to just about anything non-oxygenated, including C16. This would allow for high boost levels to maximize the turbo's capability throughout the rev range. Regardless of turbo choice, I had already decided to use a small-ish Spearco water/air intercooler with an ice water reservoir, as is often done by drag racers. This has the advantages of:
 On the minus side, it adds a bit of complication, which is never a good thing. With the turbo and intercooler more or less decided upon, I looked to manifolds, and ended up at Full-Race. Something to keep in mind for someone in my position is that while my racing is still a hobby, a lot of the important races are a long ways away. To have a multi-thousand-mile tow be worthless due to failure of a skimped-upon key part, is not a good use of resources. Full-Race has what appears to be the best reputation for quality, performance, and durability, with the only downside being cost, which I could live with on this scale. Stainless manifold before coating, likely the first production one for the KA  It just so happens that as I was ready to go for the 2871, a buzz began about the new twin-scroll Garrett GT3071R, and Geoff from Full-Race made some posts about them being in the early stages of development on a divided-inlet SR manifold built for it. This was an exciting prospect for me, for if I could get them to build me a similar manifold for the KA, the twin-scroll aspect of this .78 GT3071R just might provide the low-end needed to build huge torque in the mid-to-low 3xxx rpm range, while retaining the 3071's already great top-end pull to redline. <Insert 2-input joke here>  So, that's what I now have. It's still a few weeks away from its first trip to the dyno as I have some intercooler pipe fab to do and then I'll have the mani, turbine housing, and downpipe coated by Swaintech. The original manifold design was to use a pair of wastegates, but the final one utilizes a single 44MM TiAl. It has a 2" pipe to open dump, while the rest of the exhaust is 3" all the way back without cats. The intercooler hot-piping is 2.25" stainless to the intercooler, 2.5" aluminum cold-pipe to the throttle body. TiAl 50mm BOV in the cold pipe vented to atmosphere. Engine Management and Intake With this side of things I wanted to keep complexity to a minimum and reliability to a maximum. So many turbo cars end up with a pile of "magic boxes" in the interior that each only control one function, and I hate clutter like that in the interior. For this reason, I chose the AEM EMS very early on for its plug-and-play simplicity, and for its abillity to perform the function of just about any "magic box". Of course, it wouldn't be that simple as plugging in and going, as I'd be doing a conversion to MAP, and using the EMS to control boost via an AEM boost solenoid. One part that made the whole process a ton simpler was the xCessive Motorsports intake manifold. I know there are other options out there now, but I'm still pretty happy with this piece, as it:
Another factor that made the AEM choice an easy one is that I already know who will tune it, Shawn Church of Church Automotive Testing, whose services I have employed for a multitude of cars since 2003. He's an ace with the EMS, so I won't have to worry about anything being left on the table there. Drivetrain The job of the drivetrain behind this motor is to reliably and predictably deliver the motor's output to the wheels. There is some room for performance gain in lighter weight components. For the clutch, I have elected to go with the 7.5" twin disc option available from Competition Clutch, who also had the wisdom to help sponsor this portion of my build. Their solution is very light weight, under 19 pounds all together, and I think there's room for additional weight reduction if by drilling out the outer parts of the flywheel. The 7.5" clutch mechanism keeps the moment of inertia to a minimum, which is important to an autocross car, as we're always working in the lower gears. Overall, less weight is always a good thing too! Lightweight and overkill, just right  The transmission is being kept stock for now. I know that with close to 400ft-lbs. peak torque, I'll likely be at or past its limits. On the plus side, we don't shift that hard or that often in autocross, and the sticky race tires don't put power down as well as drag slicks or even ET Streets might. This helps keep loads on the tranny low, as the spinning tires are the "fuse" that keeps other things from breaking. I have a spare KA tranny I'll keep with me in the truck all season, and if the one in there now breaks, I'll probably look at implementing the Z32 tranny conversion for the KA, another benefit of the motor's growing aftermarket support. Driveshaft is stock for now, though I'll probably upgrade to the aluminum single-piece unit sometime over the course of the season. The R200V rear end is keeping its stock gearing but the factory viscous unit is being replaces with a 1.5-way carbon clutch type diff courtesy ATS (who also had the wisdom to offer me some sponsorship). One thing I learned from watch Jerold Lowe and Tony Capri campaign their SM 240 in 2006, is that the differential is very important in these cars. They struggled greatly through the year with theirs, trying everything from a cheap clutch-type which wore out very quickly, to a Quaife, which was useless due to inside rear tire unloading, to a welded diff, which casused numerous other issues. I have used ATS diffs before in other autocross cars, and am confident that it will provide the clamping force and longevity needed to help this car put its power down. Many thanks to Yasu Fukui for his support of my SM build!  Chassis and Suspension This part of the car was pretty well sorted from the STS build, and will be getting the least attention of all aspects. Street Mod allows the use of spherical bearings and replacement control arms, so I'll be swapping out a few. I've already done the front T/C rods with the SPLParts versions. The T/C rods rely on their ability to have multi-axis motion, which the poly bushings I had previously didn't want to allow. The replacements are also a couple pounds lighter, which is especially good. The front lower control arm is fairly lightweight and its bushing isn't bound up in normal use, so it will be staying as-is, for now. The SPLParts replacement arms allow for adjustment of both camber via an arm length adjustment, as well as a roll center adjustment at the lower ball joint. These are good benefits, but their implementation will have to wait for Phase 2. In the rear, I've already replaced the upper arms with the SPC adjustable rubber ones. I like these arms because they allow for a little bit of give and twist, which I think it needs back there to keep from binding. Also, since I've removed all the HICAS nonsense, the rear toe is handled by the SPLParts Pro HICAS eliminator kit. I really want to get the SPLParts adjustable rear lower control arm, as it would eliminate what is presently a large source of bind, and allow for some fixing of the roll centers and camber curve. I'll be trying to get those mid-season if possible, can't wait for phase 2. Doesn't help that I'm trying to buy a house here in San Diego later this year... Shocks are getting their between-season freshening up, and the rears are getting lengthened just a teeny bit so I can run the car a little higher in the rear if I want to, which I might with the taller tires. I'm also softening the rear valving - with as much power as the car is going to have, I want to be as "nice" to the rear tires as possible to keep from spinning them. I'm going to start with the same spring rates I ended up with in STS (550front/500rear), and anticipate probably going a bit higher in front, again, to try to work the fronts a little harder and let the rears concentrate on putting all that power down. Wheels and Tires Tires are one place I think a lot of potential SM'ers short-change themselves. If you look at the progression of a successfull SM car, you'll inevitably see a trend of increasing wheel and tire size. Modern autocross tire compounds are good at working at lower temperatures, and good at getting up to those temps quickly. The result is that you can use a lot of tire for the weight of the car, and have it work well. I believe that tires are the single most important of any race car, and that at a minimum, the speed equation is 1/3 car, 1/3 driver, and 1/3 tires. The rubber train finishes its journey from Indiana...  I decided to go with 285/30-18 sized front tires on 18x11" wide wheels. This is at the wide end of the range of suggested wheel size for the 285, but it's good in that it puts the tire nice and square on the rim, which optimizes response and contact patch. For the rear, I'm starting off with 315/30-18's on 18x12.5" wide wheels. These wheels are actually a little wider than the wide end of the range for the 315's, but a little bit wider than recommended (.5-1") can be just right for some tires. The 315's fit these wheels great, and the plus here is that I can try switching to the 335/30-18 (which is about 1" wider but the same height), and re-use those same wheels without worrying they're too narrow. The choice of 18's for the front was based solely on the great 285/30-18 tire, which is a popular size in the R-compound world, and should work great on the front of the 240. It's just under 25" tall, which is important to keep it out of the fender seams, which we are not allowed to modify in SM. Anything wider than the 285 is taller, which won't work. Hoosier recently announced the upcoming release of a 275/35-15, which would probably be great on the front of the car, the problem is that it would screw up the ABS with the massive diameter difference front to rear, and it might actually overheat with the 240's front being as heavy as it is. In the rear, 18's (vs. 17's) allow for the wheel to be built with some additional backspacing, which moves it inboard. In autocross, the width of the car at the rear track is a critical measurement, as it has a large impact on the speeds at which you can negotiate transitional elements. It's the sort of thing where a few inches adds up to a few tenths over the length of a 5 or 6 cone slalom - when most championships are won by a tenth or less, it's critical to keep the car narrow. CCWs look like they'll fit nicely  I'll be running Hoosiers for now, as they are the ones that come in the right widths and diameters in 18". Interestingly, BFGoodrich recently got back in the scene with a new R1 tire, and 285/30-18 was one of the first two sizes they released. If they come out with something for 18" wheels about 25" tall in the 315 to 335 width range, they might be worth looking into. Weight Reduction The car came in at 2655 pounds in STS trim, with a nearly empty tank at the ProSolo finale in Kansas last year. My minimum weight in SM will be 2560, but by adding about 70 pounds worth of turbo, intercooler, and big wheels/tires, I've got to lose about 165. The back seats were the first and most obvious things to go, along with their supports and the attached rear carpeting. The hood was next, the heavy stock one being replaced with a lightweight vented FRP one (which I'll probably replace at sometime in the future once I'm sure the turbo won't set it on fire). Those two were good for 60+ pounds. Out came the remaining emissions crap, the stereo and speakers, the rear antenna, cruise control, and the clutch damper box for another 15 or so. The entire HICAS system went bye-bye including the hard lines and control module, that's over 100 total. The rest of the weight reduction came from replacing stuff with SM equivalents - the flywheel/clutch/pp saved 15+, the intake mani was about 9, and then a bunch of STS -> SM stuff less than 5 pounds, like the control arms, fans, motor mounts, etc. I'm hoping to be within 20-25 pounds of my minimum weight of 2560 when the initial build is complete. There are a few other places so save more - aluminum driveshaft will be 10+, Z32 rear uprights will save even more, but require changes to shocks and wheels. Front brakes can save a bunch, but all that stuff gets me into ballast-adding territory. I want to stay at least 10 pounds overweight to account for scale discrepancies. Of course, there are lots more things that can be done for big $ if I wanted to go for the SM2 weight minimums (titanium uprights, 2 speed transmission, stroking an aluminum SR block, etc.) but since the car is primarily built for SM whose minimums I can get to on a mortal's budget, I won't be worrying about that stuff. Aerodynamics I'll be replacing the APR-GTC300 with a multi-element wing that I'll build myself, though that won't be done for a little while. I'm working on a new design using CFD and all the modern tricks. SM allows for a splitter too, and I should probably re-do one, but it's a PITA to have to take it off and put it back on every time the car comes on/off the trailer. I did one last year for STS but stopped using it because I was too lazy. I have a reputation for screwing with aero though, and I intend to live up to it. Some early CFD work  Driver This driver needs some time and practice in high-power RWD cars. I managed a third, albeit a rather distant one, at the 2005 Solo National Championships, in a 475whp SM2 Corvette. That car absolutely blew my senses, and when driving it, I felt that it was the sort of thing that would take me years to master, or at least realize my own potential. When this 240 is done, it should have a power:weight ratio actually exceeding that of the Vette, along with a much shorter wheelbase and less sophisticated chassis and suspension. In other words, it's going to take a long time to learn to drive it fast. I started autocrossing in an S2000 in 2002, but with the exception of 2005, I've been racing slow-ish Street Touring cars every year since, and their lack of power didn't do much to hold my interest. The DL1 datalogger I use will be as valuable as ever in tracking driver progress, as well as helping with car setup. I highly recommend this tool, or one like it, to anyone who is serious about getting better at driving, or who at least wishes to better understand what is good and bad about their driving. We geeks love the DL1 - these are my three runs from the East course at Nationals  General Strategy The autocross world got a bit shaken up with the move of the National Championships from Forbes Field in Topeka to the neighboring Heartland Park race track. The race surface at Forbes was an old concrete airfield that looked like it had been bombed, but where it was still intact, the rough concrete combined with hundreds of sets of fresh tires being maxed out on the surface, meant that the grip at Forbes was the highest many people saw all season. With the move to Heartland Park, the surface changed to a smooth and freshly-paved asphalt, with sand constantly coming up through its pores. This new surface offers significantly less grip than did the old surface, which has caused a dramatic shift in the relative competitiveness of several cars in different classes, particularly highlighting the advantage of all wheel drive. The classing and assignment of minimum weights had theretofore been based on the relative performance of a max-effort example of a given car when driven to its limits on the sticky Forbes surface. Now that the Championship surface changed, we saw the AWD cars, especially in the classes with higher power, shooting ahead, as the RWD cars struggled to effectively apply power on the more slippery surface. This was perhaps most apparent in BSP, where the Mitsubishi Evo, benefiting both from AWD and the recent allowance of unlimited boost, crushed the rest of the field, and put down times that would have nearly won Street Modified, despite running early in the first group on the first day, when the course was at its worst. Classing EVOlution?  For 2007, Mark Daddio, who is one of the very very best autocrossers in the sport (I'd say top 3 without question) both for his driving and setup ability, is further building his AWD Evo to run in SM. Mark almost won SM in 2005 with that car, when it was prepped arguably not as well as the 2006 BSP winning Evo. Meaning, Daddio is going to be unstoppable in that car at HPT, if he manages to build it to the extent he is capable. Because of this, I am very seriously considering campaigning my 240 instead in the Street Modified 2 class at Nationals. SM2 is currently dominated by the FD RX7s's of Andy McKee and Erik Strelneiks, who, unfortunately for me, are also very very very (very!) good autocrossers. Still, I think the 240 is a better match for the RX7 than it is for the Evo, at least at HPT (Heartland Park Topeka). I'll probably run SM for most of the year, but the class I choose to run in Kansas will probably come down to which days are most likely to be dry first, since autocrossing in the rain sucks no matter what, and what class will better dodge the AWD cars next. 2004 and 2006 SM2 champ Andy McKee won AS in an S2000 in 2002, the first year I went to Nationals (and finished 42nd co-driving the same S2000 that finsihed third), and I think it'd be fun to see if I've caught up to him at all in the 5 years since. So, this should be a fun year, where we get to see if something else RWD can compete with the uberwagon M3's. Bob Tunnel and Vic Sias are simply great drivers and builders - both good enough to make a successful living at it - so it will be a fun challenge to compete against them. I'll have some updates to this as the car actually gets put together and as some race results come in. Thanks for reading, good luck to everyone in finding their own 3.5mph! 
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--Jason Rhoades Last edited by J_Rho; 02-09-2007 at 04:02 PM. |
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#2
01-30-2007, 12:38 AM
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Everything you do makes me smile
 Jason...You do the kind of stuff i would do (only with SR) if I had a real salary. Excellent choice wieghing options and the turbo setup is exactly what I would have recommended for fast spool and insane gobs of torque. Keep us updated as you always do.  with that said I have one point of Contention. The AEM and Church Automotive Combo. They did a very Half-azzed job on a car that we ended up re-tuning and fixing. They got the guy onto the dyno but never botherd to double check base timing on the SR and just started tuning the result was 240 whp and 300 ft lbs of trq on a great cond sr20det with a 2871r and lots of supporting mods. When I retuned and checked the car the timing was WAAAY off and yet they just hooked it up to a dyno pack and tuned it anyways. Just keep attention to detail in mind and maybe it wasnt him Personally who tuned that specific car but thats just my experiecne with Church and Nissans. Also If you have him tune the car please use a dynometer that can accurately and precicely apply load to the drive train with the Wheels on the car and not just bolting the hubs to the dyno pack. DynoDynamics dyno , Mustang Dyno are the best in my book. Dyno jet not so much. cheers.
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http://shadowerks.com Tuning Nissans every Sunday of the week Dyno Dynamics Your Premier Tuner in Socal Last edited by steve shadows; 01-30-2007 at 12:43 AM. |
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#3
01-30-2007, 12:55 AM
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Standing up clapping...
Please keep us posted... |
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#4
01-30-2007, 04:47 AM
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Awesome write up. I'll be looking forward to competing against you :P
The scary thing is Mark Daddio is making a comeback tour.... and Chris Travis is rumored to be going boost (barring switching to the EF/ K24). SM is gonna be reeeaaal interesting. Either way, planning on making any more eastern Tours/ Pros?
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2004 FS Class G35 Coupe 6MT 1995 SM Class 240sx (KA-T) |
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#5
01-30-2007, 06:50 AM
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Excellent post, great build.
Good luck with this...keep us informed! - Brian
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'96 240SX (KA-T) ||| '05 Titan SE ||| '07 VW GTI (with DSG) ||| www.KA24DEvelopment.com |
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#7
01-30-2007, 08:40 AM
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Very Well thought out project. I am very interested to see what it does on the dyno. I can't wait for my twin scroll mani to show up. Keep us up to date on how it does this year. And good luck to you.
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Jason Team Sprock |
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#8
01-30-2007, 09:09 AM
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Sweet, I've been looking for this ever since the other thread closed. I'm building an SM 240 also but nowhere near the magnitude of this, but I also don't have alot of competition.
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#9
01-30-2007, 10:44 AM
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Quote:
on quick thought about the part above. why would you need to change the wheels? it shouldn't affect clearance much if at all, at least not where the wheel might come into play. if you do swap them out and still want to adjust the rear roll center easily, you should look into getting these instead of the factory inserts.  http://www.moonface.co.jp/mfr/roll/rollmain/index5.htm just a thought, back to reading. |
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#11
01-30-2007, 11:02 AM
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Quote:
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#12
01-30-2007, 11:05 AM
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Quote:
About changing roll center: I'm assuming you're going to use the SPL lower arms? I've been debating that or modifying the spindles themselves.
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2004 FS Class G35 Coupe 6MT 1995 SM Class 240sx (KA-T) |
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#14
01-30-2007, 11:30 AM
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Hmm, well that's good to know about the 4-lug. In reviewing the SCC build, it looks like the stock 240 rear brakes could still be used with it, 7 pounds unsprung per side is a good thing. In any case it will require new lower mounts on my 28's, which shouldn't be too hard, but it's the sort of thing where I'd want to allow a month or so of downtime - meaning it'll likely have to wait until the next off-season.
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--Jason Rhoades |
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#15
01-30-2007, 12:14 PM
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J-Rho - good thread! Lose some weight and take it to SM2.
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#16
01-30-2007, 12:36 PM
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Good thing Yasu hooked you up w/ the ATS/Carbonetic LSD! Did you go with the metal or the carbon LSD?
I would be referring to your car for feedback if you don't mind 
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#17
01-30-2007, 12:39 PM
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Quote:
Or just run a bigger motor, I suppose..... I doubt an SM legal car is going to beat the SM2 RX-7's (yeah they had a grip advantage as far as run time, but 1.3 seconds faster?), and it's not like one of them can't switch to a light/ powerful AWD car specifically for SM2. Actaully... nothing's to stop them from building an AWD RX-7, either.
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2004 FS Class G35 Coupe 6MT 1995 SM Class 240sx (KA-T) |
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#18
01-30-2007, 01:03 PM
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Very nice write up. Sounds like your car will do very nicely after a few practice laps hehe.
I have doubts about the stock trans though.... After you break your first one, you should really consider the Z32 one.
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For some, the left testicle is larger than the right one. For Larry Fedora, each testicle is larger than the other one. Last edited by GlacierFreeze; 01-30-2007 at 01:06 PM. |
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#19
01-30-2007, 02:08 PM
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Awesome! I really loved following your progression up to this point. Now I'm even more interested. Specifically in that tire and wheel combo. What is the offset on those?
I'm definitely going to be drooling for updates.
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Parting Out VQ Powered S13 Coupe Homepage Parting Out Thread - Tons of Z33,Z32,S13,S14,J30 Parts! DD Cummins '05 QC SB 6MT Straight piped on 35's w/ sound stuff, Smarty programer, tint, removed compressor housing silencer ring |
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#20
01-30-2007, 03:19 PM
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i love ccw's, great company to deal with too
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04 G35 Coupe 6MT l Cobb Tuning Springs and Sways - Tokico D-Spec Struts - Eibach/SPC Rear Camber/Toe Kit - Circuit Sports FSTB - Nismo Diff Cover - Forgestar F14 19x10+20 and 19x11+33 - Hankook Ventus V12 EVO 255/35/19 and 295/30/19 - Seibon CF front lip |
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#21
01-30-2007, 03:31 PM
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Front wheels have 6" backspace, rears have 8" The fronts require a 15mm spacer at present, might one day move to a smaller diameter front spring or something to narrow the front of the car, and then use less spacer.
Got the shocks back today from ProParts, so maybe I'll put the car on the ground this weekend with the new wheels/tires just to see how it looks.
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--Jason Rhoades |
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#22
01-30-2007, 06:41 PM
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awesome build man
that thing will rock as for the splitter, just make ramps for your trailer or get smaller tires for it. a splitter is so key if you're using a high downforce wing have you thought about doing any road racing with the car?
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Sasha '97 S14, Canadian Touring Car Championship #14 |
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#23
01-30-2007, 06:45 PM
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Great build, I love it. I can't wait to see dyno charts for that engine, and the car with everything installed. I want to read up more on the M3s, FDs, and Evos you mentioned too now, I've seen pics of them a lot and heard drivers' names bandied about, but never really learned anything about the builds.
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#26
01-30-2007, 10:59 PM
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Quote:
You won't see much detail on the 'net though, I think that's because those guys are all a lot smarter than I am...
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--Jason Rhoades |
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#27
01-30-2007, 11:16 PM
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Quote:
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Also, the success last year has made sponsorships for this stage of the build possible, and less expensive than it might otherwise be.
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--Jason Rhoades |
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#28
01-30-2007, 11:27 PM
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Quote:
Still, I would like to road race one day. Call me a snob, but Grand Am (errr, Koni) Cup and the Speed World Challenge are the only series that really interest me as a privateer. About $250k to get started with a car, and at least $30k/race weekend. One day maybe... 
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--Jason Rhoades |
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#29
01-30-2007, 11:37 PM
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so did you decide on the proper dynometer to use for tuning yet?
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http://shadowerks.com Tuning Nissans every Sunday of the week Dyno Dynamics Your Premier Tuner in Socal |
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#30
01-31-2007, 04:28 AM
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I mis-calculated my new rears, although buying them used I didn't have much say other than "i think they'll fit, i'll take 'em". (Mine are 18x12 6.75" backspacing). (http://s114.photobucket.com/albums/n...eInHole/Panda/ for pics. keeping it discreet since it's not my thread)
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2004 FS Class G35 Coupe 6MT 1995 SM Class 240sx (KA-T) |
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#31
01-31-2007, 08:58 AM
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Ace, yeah, getting used to the wider car will be part of this process. FWIW, the car should still be over 4" narrower and over a foot shorter than the SM2 Z06 I raced, and I got used to that after not too much time. I'm actually not too worried about front width, that part of the car is easier to manage on course, and in my experience, giving the front some extra track width helps put power down.
Your wheels will stick out about .75" more on each side than mine, which isn't the end of the world. You could just get new outer rim halves, to inexpensively narrow the car again, then re-add that width inboard at a later date. 315's should still fit okay on an 11.25" rim. Steve, from my perspective, I'm not so interested in attaining actual whp values - I'm more interested in making sure my motor is tuned to what I feel is the right place on the reliability vs. performance curve. I understand that the newer roller dynos like the DynoDynamics and Mustang can emulate the load-based operation of the Dynapack. From a scientific standpoint, presence of the wheel/tire combination introduces a large number of variables that I am not at all interested in learning about in this process. Heck, my best preference would be to have it tuned on a real engine dyno, but that's not going to happen. I understand you may have seen a bad result come out of his shop, and have a preference based upon that. However, I myself have had about 5 different cars tuned by him over the past 5 years (2 of which have won National Championships), and the process and results have always been stellar. Granted, by appointments have always been with Shawn himself. Still, I appreciate your input, and anyone else's input that points out potential errors, flaws, or room for improvement in my process. I'm open-minded and always willing to learn new stuff, as long as it makes me or the car faster!
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--Jason Rhoades |
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#32
01-31-2007, 11:32 AM
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double post blah
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For some, the left testicle is larger than the right one. For Larry Fedora, each testicle is larger than the other one. Last edited by GlacierFreeze; 01-31-2007 at 11:36 AM. |
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#33
01-31-2007, 11:35 AM
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Didn't remember seeing aftermarket cams listed so I'm assuming you have the stock 240/248s. After you dyno, if you feel you need more topend you should look into the Crower V2s or V3s.
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For some, the left testicle is larger than the right one. For Larry Fedora, each testicle is larger than the other one. |
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#34
01-31-2007, 12:35 PM
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Im def going to have to 2nd steve recomendation for shopping around for dyno. The impression from the car he was speaking of was a inattention to the timing map, which is pretty much what you need to be tuned for best curve and output.
If you are in socal like us, try giving AUTO WAVE in Orange County a ring, they use a dynodyamics and are experience AEM Tuners. Beautiful build btw. |
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#35
01-31-2007, 04:59 PM
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That said, I wish you the best of luck on your quest for another National Championship in 2007.
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Steve NASA Pro Racing Super Touring 1 Car# 75 Nissan S13 SR 20 DET |
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#36
01-31-2007, 05:12 PM
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Very true Steve, for a real road racing pursuit, it makes sense to learn the ropes in a more pedestrian series like the SCCA Club Racing (or NASA equivalent) series. It just seems like there isn't always a lot of depth to the fields, except at the Runoffs. Pro Spec Miata (err, MX-5 Cup, or whatever it is now) looks very interesting, and an ex-S2000-autocrosser Jason Saini has had good success there already in only his second season.
I guess I'm just a wimp - if I'm going to be risking the chance of serious bodily and financial injury to win a race, I at least want it to be on TV! Even if it is only on Tuesday nights at 3am on some obscure channel most people don't get...
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--Jason Rhoades |
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#37
01-31-2007, 07:32 PM
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That engine compartment looks great!!!!
I know you will but get a heat shield between that turbo and the MC. That reservoir will at best just deform and leak and at worst explode. Either way it can cause a fire. How do I know that? lol! Just a little fire though. We blew it out. Can't wait to see the tq. numbers. Especially at 3500 rpm. Going to be very interesting to see. Why the "need" for ABS? The advantages must be significant for your application based on the way you state it.
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Steve NASA Pro Racing Super Touring 1 Car# 75 Nissan S13 SR 20 DET |
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#38
02-01-2007, 06:00 AM
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I hope that the GT series of that size will spool better than the T3/T04e (.60 A/R housing, 60 trim wheel, .63 A/R turbine housing, stage 3 wheel ) that I have now. On the typical parking lot autocrosses I have round chi-town I pretty much have to get down into 1st gear at every turn. Otherwise it takes too long to spool in second gear. However in first gear it spools so fast I almost end up drifting one corner to the next. The setup is brilliant on the medium and high speed autocross and track days. You might do pretty well with the NASA time attacks but I am unsure what class they will put you in due to the level of modification we have.
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"I'm not concerned about all hell breaking loose, but that a PART of hell will break loose... it'll be much harder to detect."-George Carlin 1937-2008 '04 Mazda 6s 5 door '96 Nissan 240SX KA-T '91 Nissan 240SX Last edited by LigouriRd; 02-01-2007 at 06:58 AM. |
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#39
02-01-2007, 08:50 AM
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My opinion for getting into wheel-to-wheel.... karting. Although, I guess that's because I'm looking more at hopping into Formula Fords than full bodied cars. Still, karting is great for learning how to cope with other drivers, and the scale speeds are incredible, to boot.
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2004 FS Class G35 Coupe 6MT 1995 SM Class 240sx (KA-T) |
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