[prodrifterx]

i cant decide on the engine build for my car. i have a 99 GT with flows, mac cai, slp udp, and slp 180 tstat. i havent bought anything else for the engine since i have been buying tools for work and basically cant decide on the build i wanna do.

i know i want a larger displacement like 5.3 MMR based from the 4.6 block, or a 5.8 MMR based from the 5.4 block.....i cant decide if i should do a 4v, 2v, or 3v build though. i'm pretty sure/set on going with a N/A or S/C build.

what do you all think?

ima do a 6speed in the future with probably 4.30s or 4.10s because i like twists and turns and road racing more so than drag racing.

[ReverendDexter]

I think that I wouldn't be going after that kind of power for a track car unless I had some badass suspension underneath it. What are you running?

Also, if you're thinking road racing, what series are you planning on racing in? Certain combinations may not be legal, or even desireable; i.e. if you choose to run in American Iron, they have a max power:weight ratio before they bump you up into American Iron Extreme (I believe that it's 9.5lbs per hp, which translates to ~335 hp for a 3200 lb car).

[prodrifterx]

i wanna do some open auto cross first, then work my way into doin nasa or scca racing.....would like to try AIX oneday...for now nasa and scca are some obtainable goals id say....

stock suspwension since i want to do everything once and not multiple times...its going to get a maximum motorsports full track suspension....ima drive it on the street as well, already conulted MM about it...yet i have been debating the whole engine plan.

true its not all about engine power but more about control and ability to put power to the ground reliably consistantly.

[ReverendDexter]

Sorry, I'm just really confused here.

What problem with how the car behaves (for how your intending to use it) will a tremendous increase in power solve?

Wouldn't the money in this jarmongous engine build be better put towards the track pack first?

[prodrifterx]

yea ima do a suspension build first. i like to have aplan, i have a plan for all aspects of the car and details of ever part needed,...not the engine, becase i really cant decide. i could just do full bolt ons on a 4.6L 2v gt, yet i want some more ingenuity and wow factor in there....and more of a challenge on the engine. i like to challenge myself in different aspects of the build, mainly to further my ability but to also help me think outside the box for ways to make power and get power to the ground and to even be different a little bit. i want some backup for the straights that exist in many tracks. my buddy has a 94/95 gt.....minor bolt ons, springs and such, he can handle throught the turns well...better than stock cobras ---meaning can keep a stabile speed thru the track and truns....yet on the straights they catch him, but yet he'll lose them in a turn....thus my desire for some extra punch in a different from maybe.

[ReverendDexter]

honestly, I think you won't know what you want until you get there.

You may find yourself with plenty of low-end, but all breathy up top, in which case I'd say stick to stock displacement, but do fully forged internals, and build it to spin 8-9k rpms N/A. Or, you may find that the motor's great once you get some rpms under it, in which case, I'd say go for the big displacement, as that will take care of the low-end grunt. I have a feeling it will much more likely be the former, though; I can't think of a single race motor that's NOT built for rpm. Even the trans am Mustangs back in the '60s were built to pull 8k rpm and be happy doing it. Thinking about any at-speed cornering situation that I've been in, and it's mid-range torque that I need (or better shifting habits ) to pull out of corners, never low-end.

I think Doc and Sweet's build will be of interest to you: it's an N/A 4v which should hopefully see the high side of 400hp. Sure, not as much power as you could get with a blower, but I think for a road race motor, it would be much more responsive, and much more engaging than a boosty motor. Bonus, you can pick up an aluminum block, and save yourself a pretty considerable amount of weight off the front end, even with the big 4v heads.

Looking at that, it may be better for you to start with an SN95 Cobra - you'll already have the Teksid block, forged crank, 4v heads (though they'll probably need porting for what you want), and the proper ECU, with the bonus of it all already being wired Stock the motor is good to 7k, With better internals and the right cams & valvetrain, I see no reason why you couldn't build a 9k rpm monster out of it. I'm not sure how well it would handle under 3500rpm at that point, though... definitely would be interesting to find out!


Cliffs Notes:
Every racecar known to me has high-rpm motor
SN95 Cobra may be better starting point for end goal

[prodrifterx]

true...havent thoguht of the idea to keep my gt and maybe pickup a cobra or 4v car to say the least. especially with the ecu and harness being inplace.

and as much as sick wild power would be cool....id rather have a n/a high compression, high rpm car...guess it has to do with driving vettes alot.