Sbarnhart22270

I could really use some help. I just bought a 1990 RS that has been modified. My question is can anyone tell me how much hp this motor is making(I realize this will probably be just a good guess). Here is the info I have:79 350 4 bolt main- .10 over,Hypereutic .125 domed pistons with 2 valve reliefs, .510 lift cam, 1:6 alum. roller rockers, .575 lift springs
The heads are stock(79 like the block or 90?,I dont know), Steel 1.94/1.50 valves, ported and polished
Procomp airgap intake with a 1" spacer
750 Holley double pumper/mech. secondaries
MSD 6al2 ig, and billet dist.
Headman headers and dual slp loudmouth exhaust
I dont have any more info than that without tearing into it. Being as I dont have a lot of tools I will need to take it somewhere(more exp. than me). The moror feels strong.
The tranny is a 700r4(stock).How much hp can it reasonably take? It has a 2800-3200 stall conv.
The rear is a 10 bolt out of a Trans Am GTA. It has 4:10 posi, which seems a little steep for road driving.Thinking about going to 3:73 OR 3:42.
I cant get it registered until Thur, so I havent been driving around. I test drove it and took a good ride. Seems really smooth actually with good low speed driving characteristics, idles well at stop signs,etc.
Any advice for streetability is appreciated.
Thank you in advance,
Steve

P.S. This is my first post here. Sorry for the length and lack of other details.

midias

Pull the valve cover and find the head casting number.

Also what are the cam specs?

Sbarnhart22270

I dont know the cam specs. I am going to try and call the guy for more info.I am guessing the heads are prob some smog heads.The block is 79 and even the 90 350 heads arent very good either, right? They are not alu.

midias

90 350 heads are well above smog heads. Could also be 305 heads. Pull the valve cover

2005Impalla

90s heads would be center bolt valve cover. Motor could be any were from 325-400 HP is hard to say probably in the 350+ range though. Sounds like a good mix of parts though. I would keep it how it is.

2005Impalla

Kinda weird to port and only have 1.94 valves though.

Sbarnhart22270

Well I have more info. The cam is a Jegs flat tappet with a duration of 252/302. It has a .510 lift. The heads are 79 350. In all honesty the motor feels really strong. Finally got everything legal and went for a long drive. Runs great. The only problem is the exhaust dumps at the rear axle and it is pretty stinky inside. Guess I will have to run it all the way back.
What do you guys think about the tranny. Will it hold up, being stock, or should I be looking at getting it rebuilt? It didnt give me any problems. I was just curious.
Thanks for the responses.

Sbarnhart22270

Sorry typo : the duration is 292/302

Ozz1967

iTrader: (4)

Best way? Put it on the track and run a 1/4 mile on the clock. There are formula's using your ET's that can determine horse power.

midias

This cam?http://m.summitracing.com/parts/sum-1107

It might make 350 HP but those low compression heads are killing it. Not getting into the powerband it wants. Probably 882 heads stock with 1.94 valves

Sbarnhart22270

http://www.jegs.com/i/JEGS-Performan...ductId=1215318 This is the cam.

Sbarnhart22270

Would you switch to Vortec heads and intake?

midias

Looks like a near clone of the edelbrock RPM cam PN7102.

That cam is going to want to spin up to 6500 to make use of the profile. I would probably not go factory vortec heads although if your running 882 heads they would be an improvement if it did not bump you compression to high.

The previous owner probably installed domed pistons to make up for the 76cc chambers in the heads he used. I would figure out the parts you have and the static compression, get some decent heads 185-190cc intake and keep the compression between 10-10.5 to take full advantage of that cam. Also keep in mind with those rockers your exhaust is at .544 lift and you need to keep some clearance.

Sbarnhart22270

Thanks for the info. It really amazes me how much stuff you guys know. I am kinda broke now so anything I do is gonna be in the future. I just need to formulate a plan. Thanks again.