I know there are a lot of questions floating around about 383 strokers but I can't seem to find the answers that pertain to mine. I saw a Vortec 383 that SDPC did and they had most of the parts numbers there, so that's where i'm getting most of these parts. I already have a 350 block, so i'm planning on getting:
the Vortec heads (L31) assembled and the RPM air gap intake
a Q-Jet carb

I don't know which headers to use, which cam, i'd like a roller cam, but i'm really open to ANY sugggestions. This will be my daily driver, so gas mileage WILL be an issue. I've got a 700R4 now, but I'd like to swap in a T56, but I'm not certain. I'd like to get atleast 18 MPG if not more, and have reasonably good street manners, but able to burn the tires, and smoke pretty much any car I can. I'd appreciate ANY help, thanks.

 

im also interested in some info too, sounds like im trying to build about the same set up you are except i think im staying with TPI, nothings final though

 

I don't know if a TPI setup will support a 383, unless it's a highly modified TPI. Just my $.02 though. Good luck.

 

You may need the larger tubes and plenum from Accel or another company. On my Desktop Dyno 2000 the engine with Comp Cams

XE262H-10 would make approx. 325 hp and 430 lbs tq.
XE256H-10 would make approx. 320 hp and 440 lbs tq.
XE268H-10 would make approx. 340 hp and 425 lbs tq.

XR256HR-10 would make approx. 356 hp and 476 lbs tq.
XR252HR-10 would make approx. 341 hp and 486 lbs tq.
XR264HR-10 would make approx. 367 hp and 468 lbs tq.

 

To get 18mpg out of a 383 I would highly consider a mild hydrualic roller. You will have gobs of torque and be able to run a conservative rear gear. I have a 475hp 383 in a 69 camaro and gas mileage is one thing that sucks. Burnouts are as easy as a big block though. Good luck, if you do get 18 mpg with a carb let us know so I can put one in my 86 Z-28.

 

Accel Superrams with 58mm TBs seem to be a popular choice for a heavy breathing 383. they should flow up to 5800 rpm which is above most peak HP marks for average 383s.

 

Well, I have TBI right now, and I don't want to spend the money to get a Superram or anything. I figured that a carb was the cheapest way to go. But, I do want around 18 MPG with it in my 383. Is this not possible, withouth sacrificing gobs of torque for the mileage?

 

you'll never get any decent fuel economy with a carb. Not to mention emissions might be very hard or impossible to pass depending on where you live. Holley makes after market TBI systems that are reasonably priced and can probably give you adequate breathing and fuel economy on your engine.

 

Ok, so the carb idea's out. I NEED good fuel economy. So, what would be the best aftermarket induction setup for a 383? I still need good fuel economy, so any aftermarket intakes a good compromise between power and fuel economy? Again, this will be on a Vortec 383 stroker which is in the planning stages now. Again, thanks.

 

Actually, a properly tuned carb can be just as good on gas as most EFI systems.