Richard lambert
Newbie
How do I put a 400 SBC in a 1992 gmc with tbi I still want to use the tbi
400sbc
- Thread starter Richard lambert
- Start date
Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.
Captainfab
Newbie
Two main things. One is you will need a bigger throttle body. The throttle body from a 454 may work. I know they do on a 383, but not sure on a 400/406. Secondly you will need a way to data log and tune your PCM.
1. Different flexplate since the 400 does not have a one-piece rear main seal, and therefore has the older, larger bolt circle on the back of the crank. Be sure the flexplate you choose has the appropriate balance for your 400 AND the appropriate bolt-circle for whatever torque converter you're using.
2. Make sure the 400 torsional damper timing mark lines up properly with the timing indicator you have. Pretty good chance you'll have to change timing indicators, or re-mark the damper.
3. Lots of computer tuning, AFTER you install all the appropriate sensors and such into the 400 engine. Knock sensors are supposedly different between 305 and 350; I don't know what you're gonna need on a 400. As said, you'll need a computer-controlled distributor, the entire computer wire harness, a suitable fuel pump, etc.
4. Putting a roller-cam and roller lifters in the 400 block will require really-expensive parts. From a practical standpoint, you're "probably" going to be limited to a flat-tappet cam. Good Luck. I would make sure a flat-tappet cam was nitrided, and use only top-quality lifters...but then I'm severely allergic to flat-tappet cam/lifter failures.
5. I don't know if a typical 400 oil pan clears the rest of the chassis. The oil pan from the original engine won't fit, I think the dipstick is on the wrong side.
2. Make sure the 400 torsional damper timing mark lines up properly with the timing indicator you have. Pretty good chance you'll have to change timing indicators, or re-mark the damper.
3. Lots of computer tuning, AFTER you install all the appropriate sensors and such into the 400 engine. Knock sensors are supposedly different between 305 and 350; I don't know what you're gonna need on a 400. As said, you'll need a computer-controlled distributor, the entire computer wire harness, a suitable fuel pump, etc.
4. Putting a roller-cam and roller lifters in the 400 block will require really-expensive parts. From a practical standpoint, you're "probably" going to be limited to a flat-tappet cam. Good Luck. I would make sure a flat-tappet cam was nitrided, and use only top-quality lifters...but then I'm severely allergic to flat-tappet cam/lifter failures.
5. I don't know if a typical 400 oil pan clears the rest of the chassis. The oil pan from the original engine won't fit, I think the dipstick is on the wrong side.
Similar threads
