Advice needed - potential of 300ZX in new SCCA ITR race class

[Limey]

I wanted to get some advice on the potential of this car. Here are the aloowable mods:

Engine

0.5 compression increaseCAI in engine bayexhaust headers/cat removal/race exhaustcan port match intake/exhaust only 1" into headstiming freecan go 0.004" overborecomputer mods - anything that will fit into stock ECU box - no piggy-back systems.can use underdrive pulleys

Other stuff:

Race weight 3250 lb with driver.Wheels 18 x 7.5 max. Tires DOT legal e.g HoosierSuspension/swaybars pretty much freeBrakes - race pads, but stock rotors and calipers.

Really interested in your thoughs on what rear wheel HP this thing can produce with the mods above.

My only other concern would be braking potential....think it will eat pads at that weight.

Anyway, I appreciate any feedback.

Cheers, Limey

[freakonaleash1187]

Are you talking about a N/A Z or a TTZ? The stock brakes on a Z are ok, but when you get up to speed, the aren't really that good. My buddy in his TTZ with stock brakes and upgraded pads took it to a road course event and his brakes were horrible and mushy by the end of the event.

[Limey]

N/A

no forced induction in IT classes

[nsrZ32]

You should be able to make 200whp and have a very very responsive car and make it handle like a dream.

I'd go for it.

[freakonaleash1187]

If you can do whatever you want to the suspension, you will be able to make it handle wonderfully. And like NSR said, you will make about 200whp. But the drawback is the brakes without being able to upgrade those.

[Limey]

yeah, I think you are right - the brakes will be it's achilles heel.

However, regarding power potential, a friend of mine that races, had this to say:

Mark, one of the ITAC guys gave us dyno sheets for this car in SSA in the early 90s. Just an exhaust produced 220 hp at the wheels. The car has been debated ad infinitum on the IT board (imagine that). Consensus is wicked fast due to aero and power, potential brake issues.

Is that possible?? 220 RWHP from just an exhaust??

Thanks for the advice,

Limey

[freakonaleash1187]

If he is talking about a N/A Z, then that is impossible. It will take a lot of time and money to get a N/A Z up to 220whp, and I mean A LOT of time and money.

[evildky]

remember also that not all dyno's are created equal! and I guerentee you an engine build by sunbelt or robello is gonna ut down more than the run of the mill machine shop, ans they know the limits of what is assloed, and without digging form my GCR I'm gonna say the allowed overbore is actually .040

[Wetmyson]

3250 lbs with driver? i don't think even a stock n/a z would pass that.

[freakonaleash1187]

I think he means that is the minimum weight?? Maybe?

[evildky]

thats minimum weight and you guys gotta remember he's gonna have a gutted interior with no HVAC, sound deadeing should ideally be removed, it should be devoid of anything that doesn't make the car stop go or turn, with the addition of a full cage and a fire suppression system, I'm gunning for 2700 lbs wet with driver in my Z31, similar starting weight and I don't need a cage or fire supression

[unclejoe]

I've been running a 300ZX in SCCA since 1995. The 300ZX is too heavy w/too little hp to run with the BMWs etc that are racing ITR. Like someone said earlier, you haven't got enough money to pull the 300/325 hp you'd need to reach 1hp/10lb to compete. ITR rules also require "stock brakes" (not even drilled rotors are allowed). A properly prepped Z is a handling dream (areodynamically superior too!) But ITR is the wrong class for you.

I think you'll find that the ITR rules aldo call for a Race weight of 3250 lb without the driver - the SCCA listed stock weight. You certainly can get 2750lb without a roll cage, but you can't (and shouldn't even consider) running IT without a full-strength cage. Mine is 2870lb (w/out me) with a full NASCAR-type cage (you don't want to hit a wall at 120mph much less 150mph without that protection, and you sure don't want to get hit by another 2,500-3,000 lb car without that much protection). That said, do you think your 3250lb/250hp Z stands a chance against a 2900lb/325hp BMW? ITR is the wrong class for you.

That said, if you want to run it, prep the body/suspension for ITE - once you get the handling set, swap in a 4.5L V-8. The transmission adaptor ring is the only trick piece there - but prep the car first! Don't do engine stuff while you're sorting the car out!!

I've got some photos at http://unclejoe.com - and we just won two races at the California Speedway. The V-8 is next ;]