My friend has just installed a 383 stroker in my 95 Chevy Z71 4x4 and it has absolutely no take off! The engine is really loading up hard on fuel until the rpm's get to about 2500-2800 then it pulls somewhat but not the way I feel that it should. Useing the stock tbi, vortec heads design for tbi, cam shaft duration @ .050 is intake 196 exhaust 206. Lift is 431 intake, 451 exhaust. Lobe centerline 109. This cam is the ram jet cam from Scroggin Dickies. Roller rockers with 1.5 ratio. Compression from Keith Black pistons is 9.1. However the engine is really loading up on fuel badly and can't figure what is causing this. He did a compression and leak down test on the cylinders and everything checked out good, but the #6 sparkplug being completely black and sutty. Anyone ever had this problem with a tbi 383 please give me a reply. I really want to get this engine going strong. Thanks.  

For one thing this TBI is going to be awfully restrictive. Increasing displacement sometimes isn't a good idea if the you retain the stock components that can barely support the stock displacement...

Did your friend have a chip burned for this thing? What is the fuel pressure? It almost sounds like a distribution problem if only plug is bad so check the condition of the injectors as well.  

Sounds like the first problem is the torque converter needs to be changed. The different cam profile and powerband of the 383 is probably not fiting well with the stock converter in your truck. Take your cam specs and rear end gear ratio and call a company like TCI or JW Transmissions and order up a torque converter with a better stall speed for your engine.

Second, you'll defintiely need a chip for the computer that'll let you get the most form the motor. With the stock chip and the 383, the computer's probably not giving the motor enough timing at low RPM to burn off the fuel. That, and the stock computer tune might not have the fuel/air ratio right. The TBI unit isn't that restrictive (I have a '92 Silverado so I know this system well), the only thing you might have to look at doing is swapping in the injectors from a TBI equipped 454 so you have plenty of fuel flow to the 383.  

Thanks for replying guys. Yes in fact I had a chip burned for the set up that I am using. It helped big time, but I am still having a rich condition. Fuel pressure was adjusted to 13 psi.  

It may just be that whoever burned the chip thought this engine would need more fuel than it really does at these rpm's. Calling someone on the phone and telling them to tune the engine just isn't the most accurate thing to do. I can't really think of anything else that could be causing it. It doesn't make sense to me because an engine this highly modified should want more than 13 psi of fuel pressure (that's a stock spec) but it is already getting too much fuel. Try getting back to the person who burned the chip and see if he thinks it may need some more fine-tuning...

This vehicle does not need a different stall converter if the stock is in good condition. The duration @.050 is similar to a stock cam and the power band only goes down when the stroke is increased.