Ilike2stroke383

I have a built 383 stroker that should be at 500 horses with a good carb. Right now it has an edelbrok 750 with vacuum secondaries, it has a major vacuum leak at the carb. Plus I need to swap it out anyway because i swapped the 700r4 for a t56.

I have been told that a Holley 750 Double Pumper will be best. I just want to make sure before I spend all of my money on a new carb. I will be taking the car on a 1400 mile drive in a few weeks so I can finish my last few classes at Wyotech. Gas mileage isnt extremely important, but the car wont really be raced much. I dont want a carb thats going to get me horrible gas mileage, then again I dont want a carb that stumbles when i get on it either.

My friend who had the car before me, built the engine and swapped it from an expensive fuel injection setup for the carb setup, but didnt get a good enough carb for it due to money restrictions. He's telling me that even with the double pumper, i should get around 18-22 mpg highway because of the overdrive of the t56 tranny. What do you think? Its a built 383, with .5 overdrive, and 3.42 rear end posi.

Next, what would be a good fuel pressure to run this engine at? When I first got, it was at 10 psi and thats with a holley fuel pressure regulator fully restricting the psi. I now have another fuel pressure regulator inline and its fully open and the psi is at 5. Is this good or bad? I still new to carbs, never had one before, ive always tuned efi.

Thanks alot guys!

Apeiron

The carb isn't going to have all that much effect on peak HP as long as it's tuned correctly.


Edelbrock's carbs don't really have vacuum secondaries. They're mechanical secondaries (but not double pumpers), with an air valve.

That's about what I'd use.

That's going to depend mostly on your driving habits.

5 PSI is fine. Too much pressure and the needles are forced off the seats and the carb floods.

Apeiron

Give people a chance to read your post before you bump.

stroker_SS

I have to agree with apeiron here.


I do have a question, how do you like your t56 so far? What kind of bellhousing/clutch(mech./hyd/t5 or ls1) setup are you using? Shifter? Was your car an auto before you swapped? What center console?

Ilike2stroke383

Im actually in the process of getting it in, but ill be done tomorrow. Stock T56 bellhousing, lt1 t56 hydraulics. stock shifter. Yes it was an auto.. and the automatic center console. I just cut the PRND21 symbol off and it looks stock.

stroker_SS

Cool, I had no idea you could re use the stock center. You should post some pics of it.

What made you decide to go with the LT1 setup?

All I know is when I do my t56 swap I want to stay away from the LS1 hydraulics. They are too high maintenance.

Ilike2stroke383

i went with the lt1 because its pretty much a direct bolt in with everything. With the ls1 **** i would have to get new driveshaft and other stupid stuff. lot easier with the lt1. ill post some pics soon of the car and the center console. I just broke the drive lettering off and it looks like it should with a manual. it was already indented so it was easy taking it off.