the road racer rebuild

rocksteadyracer
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the road racer rebuild

Postby rocksteadyracer » Sun Jan 27, 2013 7:11 pm

I'm planning a TVIS 16 valve rebuild in my 87 GTS race car, planning on using mild cams, a litle bump in compression, leaning toward reliability more than HP, planning on keeping stock ECU, otherwise I'm bumped into class I don't belong How far can I go with the build before the TVIS gets in the way or is a small port head better

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oldeskewltoy
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Re: the road racer rebuild

Postby oldeskewltoy » Tue Jan 29, 2013 10:41 am

rocksteadyracer wrote:I'm planning a TVIS 16 valve rebuild in my 87 GTS race car, planning on using mild cams, a litle bump in compression, leaning toward reliability more than HP, planning on keeping stock ECU, otherwise I'm bumped into class I don't belong How far can I go with the build before the TVIS gets in the way or is a small port head better


What are the rules to your CURRENT class??? Frequently the rules allow little if any changes....

but if the only limitation is to run the original ecu... with proper parts mixing(ported head, cams, compression bump[pistons], injectors) you can boost power by about 25% to 30%.... maybe , just maybe if it is all done perfectly... you might be able to achieve a 35% gain... but it is highly unlikely with stock management to get to 35% improvement
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

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rocksteadyracer
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Re: the road racer rebuild

Postby rocksteadyracer » Wed Jan 30, 2013 9:36 am

am I better off with a small port head? I just never saw anything like these butterfly valves between the head and intake I am considering a megasuirt MSPNPS T8590

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oldeskewltoy
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Re: the road racer rebuild

Postby oldeskewltoy » Wed Jan 30, 2013 3:07 pm

What rules are you following????
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

rocksteadyracer
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Re: the road racer rebuild

Postby rocksteadyracer » Wed Jan 30, 2013 7:43 pm

forget the rules focus on the build, the key is to build the car you want to drive and find a class it will fit in, we'er an amatuer club we race for plastic trophies, I race against a lot of sec miata s that cross into ITA, and some I can run with and others pass me like I'm standing still, who's cheating

rocksteadyracer
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Re: the road racer rebuild

Postby rocksteadyracer » Wed Jan 30, 2013 7:44 pm

the rules are co$t

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oldeskewltoy
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Re: the road racer rebuild

Postby oldeskewltoy » Thu Jan 31, 2013 9:07 am

rocksteadyracer wrote:forget the rules focus on the build, the key is to build the car you want to drive and find a class it will fit in, we'er an amatuer club we race for plastic trophies, I race against a lot of sec miata s that cross into ITA, and some I can run with and others pass me like I'm standing still, who's cheating


engine for running on stock TVIS based ECU(option1): ported largeport head, 256 cams, compression of 10.75 to 1, quality 4/2/1 header, 240cc injectors, exhaust diameter no larger than 2.25"

engine for running on stock TVIS based ECU(option2):ported smallport head, clip and flip smallport intake manifold, 256 cams, compression of 10.75 to 1, quality 4/2/1 header, 240cc injectors, exhaust diameter no larger than 2.25"

The smallport option will provide a bit more low end pull, but after that they should perform nearly identically. The largeport version is MUCH less obvious(harder to tell) as a "cheat"...

Either of the above engines should plant 120-125 wheel horsepower, or about 135-145 crank horsepower. The stock engine is rated @ 115 crank horsepower, or about 100 wheel horsepower. That should move you closer to the front of the field, but if you are looking to LAP the field... you might look at building something along the lines of this....viewtopic.php?f=7&t=1026 :o big budget needed for that
OST Cyl head porting, - viewtopic.php?f=22&t=300

Building a great engine takes knowing the end... before you begin :ugeek:

Enjoy Life... its the only one you get!

rocksteadyracer
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Re: the road racer rebuild

Postby rocksteadyracer » Thu Jan 31, 2013 7:06 pm

thank you my friend off to the biulder my pre build dyno was a hair under 100 hp

rocksteadyracer
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Re: the road racer rebuild

Postby rocksteadyracer » Thu Jan 31, 2013 7:08 pm

next off season one of your six speeds