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So i'm trying to help this guy get going in ITS, he just had his first race weekend and was disappointed in his lap times. I'm not surprised, as he's got a freakin street car with a roll cage in it (even rolled across the scales around 2900lbs).
he's got some sort of aftermarket shocks, a cone filter, header and exhaust of unknown origin.
i've been trying to read up on these things, but i have next to no experience with the P-Cars. he wants to build the car to be legal to run in both SCCA ITS and NASA Spec 944. if you were to prioritize your build with keeping a limited budget in mind, what would you change that would have the most dramatic effect on laptime/$.
PS - ITS isn't very competitive in this division, so pro-motors need not apply.
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LOL... well, gut that puppy and get the weight out... and ditch the cone filter, get proper cold air into that engine - stock would be better IMO than an open cone.
As long as the engine's solid, I'd leave it alone; new rod bearings if they haven't already been done, belts of course, check leakdown, maybe re-lap the valves, make sure it's running right.
It's all about the chassis, setting it up right, and learning how to drive it. So he needs big torsion bars and springs to match - 30mm and 350-400# springs. Hopefully his shocks are the Koni Yellows; not optimal IMO, but better than most and legal for Spec. For that matter, if he wants to run Spec, he should just get all those bits and put them in, it's an excellent yet cost-effective package. Get rid of all the old stock 20-yr-old rubber bushings, for sure.
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thanks vaughan.
the engine was recently rebuilt, so it should be ok. i actually drove it a bit on the street and the motor feels fast to me coming from a miata.
who sells a proper race intake and exhaust for these things? are they good for much in the way of power gains?
does it have to be a 30mm solid bar, or can it be the 33mm hollow with the 30mm eff rate?
i asked him at lunch, and they are koni's of some variety.
best place to purchase the torsion bar? i assume GC will be fine for the front spring/perches?
which bushings are the ones that deteriorate? all of them? better to just buy new arms with the bushings already pressed in?
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Getting the rear torsion bars re-indexed is a big job. You can lower to car some by adjusting the torsion bars, but you really should look into reindexing to really level the car.
Make sure you bud is running race pads, not street pads.
Get a set of really lightweight wheels.
Go to the dyno and tune the motor as much as you can.
Put delrin or urethane bushings in.
These cars are only competitive in the Northeast with a pro built motor. I ran an 87 944 in my first year and sold it. The cost of getting the car competitive was less than buying a front running ITS RX7.
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I think you need to get a copy of the S944 rules and prep to that. Then you can run both.
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Spherical are preferable to plastic - but the whole kit (from Racer's Edge) is $1350 or so. I have mostly spherical stuff. I get the vast majority of my stuff, particularly chassis, from Paragon Products.
Hollow bars are labeled by the effective solid rate; 33mm hollow bars should be larger than 33mm, but equivalent to a solid bar of OD 33mm. I run 34mm hollow bars, but they are slightly larger than 34mm OD. But you and your buddy need to read the rulebook before he spends any money; 944 Spec requires the Spec package, which means 30mm max rear t-bars.
You can't really change the intake either, in ITS. That pesky rule thing.
Header, the ultimate is the Stahl header. Costs $600. Busch are cheaper. Probably not as fast.
You get to run a crank-fire ignition. Apparently that's a wonderful thing to do on these; stock ignition to start, then switch over to a fixed ignition.
RE: bushings - can you think of anywhere on your chassis you'd like to have 20-year-old rubber to race on??? Replace all, of course.
IMO Koni's are too weak for the spring rate needed to really race these; that's why I run custom Bilsteins. Of course, those aren't legal for Spec. I suppose it's a good thing RR shocks aren't legal for IT, or I'd be lusting after a set of Motons; the guys who run NASA and PCA do run those, and they're killer, apparently.
More resources - check out the 944 Spec forums on the NASA Forums. They have a great deal of knowledge there.
JME, Jon Milledge Engineering, is the 944 expert. I hear he's selling off and getting out. If nothing else, get a copy of his prep book - tells you everything about prepping a 944 for ITS racing.
As for suspension and rear torsion bar setup, alignment, etc - get used to it, if you're going to be racing one. Try to set the rear at home and forget it. If you're not continually fiddling with settings, changing bars, or hitting things, you should be able to leave the rear alone. Do so. On the plus side, everything's adjustable stock!
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Ben -
I think he's got some sort of street based Hawk pad, this is one thing i need to talk to him about when it becomes time to replace them.
I don't think the lightweight wheels are legal for Spec944.
Are there lots of gains to be had by adjusting timing and fuel pressure? if not, what would be the benefit of dyno tuning?
Andy -
Agreed.
Vaughn -
how much of a wear item are the sphericals? when i say ITS isn't competitive around here, i mean really not competitive. As in I often run better times in my SM. so if poly will work ok, with no real need to replace, and significantly cheaper, that's probably the best option for him.
thanks guys. this helps.
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I have never been unhappy with my KFP Magnums... (hmm, sounds like a condom!) Anyway, great pads, real easy on rotors, never burn 'em up, last for a long time on a little 924.
I believe you're correct, and Fuchs aren't legal for Spec.
I've found the sphericals to last a long time... still on my first set, 7 years in. I've heard the poly do wear out, and so are now hard to find - not offered any more for those reasons, at least for the A-arms. In the rear, delrin and poly are fine for the t-bar bushings - that's what I'm running - but spherical is the only option for the trailing arms. Don't forget the rear suspension mounts, and camber plates up top in the front are a necessity.
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Chuck Moreland might have some poly-bronze bushings for the 944 at elephant racing. i have them on my street/track 911, and they are pretty trick.
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While bushing material may be free in ITS, only "non-metallic" bushings are allowed in SPEC944.
Back to your original post, "prioritize a build..".
Do the safety stuff needed to pass tech(which you must have already done)
Strip the car of everything the rules say you can. If you're not sure you can remove it, ask on IT.com or Spec forum
Examine condition of all neccessary systems, brakes, cooling, ignition, steering, suspension, drivetrain, exhaust, etc. and do routine maintenance, change fuel filter, air filter, etc.
Replace worn/damaged/inferior components with legal performance enhancing pieces where possible.
i.e. remove catalytic converter install performance exhaust and muffler, change torsion bars- 30mm only for SPEC, install SS brake lines, Crossed drilled or slotted rotors for SPEC but not for ITS, K&N filter, SPEC has specific shocks, bigger radiator in ITS but not in SPEC, etc.
Now for the most dramatic changes in laptimes you asked for:
Track time
Install race tires
Get racing spec alignment
Track time
Corner balance
Track time
Install LSD-big help for laptimes
Track time
Install chip for ITS but no longer legal in SPEC
Track time
Track time
Rinse and repeat
R.L. Mitchell
[email protected]
www.RPM4performance.com
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Hi Travis. Ive built 2 944 ITS cars, one with an 8 valve engine the other 16 valve. Ive worked with Milledge and other really good engine builders. Have a lot of data and dyno info and happy to discuss if you want to PM or email me [email protected]
Russ Jones
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I am the Arizona director of 944 spec and have been involved in 944 spec since 2002. I also have been closely involved in the 944 spec rules for 5 years. I built my 944 from the ground up back in from 2000-2003, have held several track records and was the 2006 Az region champion. I have also built 2-3 motors at home so I know what it takes to make strong 944 spec car. I have never raced in SCCA however.
Making a car 944 competitive for ITS will leave it not legal for 944 spec. A competetive car for 944 spec could be ITS legal if you made build just right.
http://944spec.org is the place for the 944 spec rules. They are considerably more restrictive in suspension, engine and tranny rules. They are however more liberal in what can be removed to make weight (2600lbs with driver). Tire and wheel rules are also limited on 944 spec (toyo RA'1 and 2 types of stock wheels) and more open in ITS. However a good thing to do would be to have a ITS wheel/tire and 944 spec wheel/tire.
Care must be taken when building the for both series. In general the 944 spec prep rules are more restritive, but they were not based on ITS rules so differences do exist.
I would think a well prepared 944 spec car would a lower mid pack ITS car. Lap times would probalby just off the best ITA cars asssuming the driver gets all they can from the car.
If you want all the details on 944 spec prep visit http://nasaforums.com and look in the "944 challenge" area.
I would happy provide all that I know about 944 spec prep, but don't visit this board all that often. Sadly I know little about ITS rules other that what I have read (limited).
My contact info in on the 944spec.org website under "contacts".
Build priorities are
1) Replace worn parts to make the car reliable
2) Weight reduction
3) suspension / aligment
Key to all of that learning to drive the piss out of the car to improve. Most new 944 spec drivers are new racers and they will see 3 to 10 second lap time improvements just from driving skill improvement from seat time.
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Depending where you live, you may consider building the car for 944cup, the "other" 944 class in NASA. Here you can run a 944 in full ITS trim and kick everybody's ass :D
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sorry guys....had a race last weekend and completely forgot about this thread.
the information and advice is very helpful.
russ you'll have an email from me shortly.
joe ITS in our division is not very competitive at all, so a nice spec944 car should be just fine around here. i totally agree with you that weight is the next item i need to get my friend to work on. i'll be sure to link him to this thread.
