well guys i had bought a 350 motor that was a 4 bolt main, bored .030, and somewhat fresh rebuild and a th350 tranny all for $150.




Got it installed, had new 2.5 inch exchaust put on it and got it inspected. ran great and was snappy. had a vibration while I drove it down the road at like 35 but if you put the car in neutral it went away.

Now here is the but. Everyday I drove it, it seemed to loose more and more power. then after a burn out, I mean right after the burn out it idle rough. and when you drove down the road with the throttle in at a consistant pace the car was like in and out. Found that cyclinders 2 and 8 were dead i pulled #4 and the car shut off and couldnt start it back up because the appendix on the starter broke. did not do a compression check. instead i took the whole motor apart everything seemed to be normal were and tear. main bearings had some grooves and they had like a brownish color to them. Oh and the motor was not bored at all. What do you guys think happened.

Which brings me to my next topic. If any here could give me an estimate on my hp/tq on my new build up.

383 stroker with flat top pistion.
64cc heads, stage 1 ported, and valve size undiced at this point either 194/150 but most likely will be 202/160 if you can give me numbers for both that would be great.
cam: hi rev from 2800-6000 int/exh both 436 and lift both 436
going with and edlebrock dual plane air gap intake
750 cfm carb. havent decicded wether to go with edlebrok or holley

also undiced on rocker ratio i know if i go with 1.6 i will get more lift but have now idea what it will do power wise as i'm still new to this and learning as i go. I have a friend that is helping me out on this.

Do you guys know what the stock gear ratio is in a 84 firebird.

Finale question is the th350 i need to get beefed up talked to a local guy about rebuilding it and putting in a shift kit. he wants 1025. Or should i just get a trans from summit for 900 that comes with a torque converter.

sorry for the long read and thanks for any input/suggestions.

 

Nothing about your proposed build looks right to me. Well, the 383 part is good. 11:1? NO. 436/436 cam? NO. TH350? NO. Mystery gearing? NO.
read the first 7 posts of this thread: https://www.thirdgen.org/forums/engi...st-builds.html
I'd bet all 6 of the 383 combos mentioned therein are making more than you hoped to, and only one of them is over 9.5:1 there are full details and real dyno details on 4 of them

 

Don't forget mystery heads.

 

good catch!

 

opps the cam is 224 and the lift is 436

 

Anyone else. I already got the kit and it came with the cam.