Thread: 350 engine build info?!

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Hey people just want to know some stuff about the engine build i'm doing? Firstly i'm new here, i'm from the UK and into my US GM's, as the user name states. I'm in the middle of building a new "street sleeper" caprice 4 door sedan. I know it's not a hotrod so to speak but hey. I used to have a 77 sedan with a 330hp 350 before this new one, but sold it to make way for other things. Now i have an 80 sedan which i'm building a SBC for, hence my posting here and the question!

I'm gonna use a 2 bolt mains 78 engine block as a basis for a 383 cubic inch stroker. Using a forged crank and rods with forged pistons.

Q 1. Whats the best compression ratio to have in this motor?
Q 2. What heads do i use iron or aluminum and valve sizes ect?
Q 3. Whats the best cam durations?
Q 4. Whats the best carb to use i was thinking of a 600?

The car weighs about 4000lbs and is stock (and real tidy) I want torque and lower RPM HP due to the TH350 and 2.41:1 rear end, plus i drive the car on the streets everyday (in the summer) Here in the UK we have regular (premium) gas thats 95 octane. So tell me guys whats the best setup on this motor gonna be??? an what the HP and LBF to go with that (estimate)

Cheers for any help here, as i have never built a stroker..

You could build a clone of my 383. It dynoed at 450 hp and 467 ft. lbs. of torque. And it is very street friendly. Here are the specs:

AFR 195 heads (I used their 190's but they don't make those anymore)
SRP forged pistons (10.6:1 static compression; 8.42 dynamic compression)
Eagle I beam rods and cast steel crank
CompCams 280 Magnum single pattern flat tappet cam (.480 lift; 230 degree duration @ .050)
CompCams Magnum roller rockers
Edelbrock RPM intake manifold
Edelbrock 750 carb
Beefed up 700R4 transmission with a 2500 stall converter.

If you have the money, you could upgrade by using CompCams hydraulic roller version of the 280 Magnum cam. If you do, I would add AFR's rev kit.

Welcome Big Guy!

I concur with rumrumm - thats is a sweet motor that's dependable, strong and won't place you in the poor house to build or run. It will start and purr like a kitten on 95 octane yet come on very strong when you open up that 750.

This, in my humble opinion, is the perfect combination of streetable power, fun and a bit of sanity!

Good luck and let us see some pictures of your ride and the progress of your build!

Glenn

Thanks for the replys people, i like the look of that spec rumrumm. My local parts shop sell's Keith Black forged pistons and RHS heads. But i can get Edelbrock performer heads and manifold. What's AFR, not sure i have heard of them? Is your 10.6:1 static compression too high for iron heads? One guy told me that the ratio for a street chevy is not going over 9.5:1 for 95 gas?? This is what confuses me! I was hoping to keep it all iron so it looks stock (ish) under the hood. But iron = hotter motor? Whats the highest safe compression for a all iorn motor? Or should i go aluminum heads do ya think? So much choice has me going in circles..... I like the power of that 383 though would suit the caprice nice.

I will post some pic's as i go but currently here it is! It's a show room 1980 caprice with 62.000 mile FULL HISTORY to back that too! It's from Florida. Currently has a 267ci which is real sluggish, shame to take away the originality but i plan to keep it so 383 here we go!
The last pictures are the last "sleeper" i had, 1977 original 350/350 but bored to 355ci with HO pistons heads ect about 330 hp, TH350 shift pack & 3:1 locker rear end