454 to 350 4l80e
 

Hey guys got some questions. I swapped a 350 into my Dad's 95 2wd Dually. It had a blown 454 in it. The donor 1500 that the engine came out of has a 4l60e. Which computer should i use? Will the half ton computer run the 4l80e or will the 454 computer control the 350? Also I havent hooked up the exhaust yet would open manifolds cause the knock sensor to throw an elctronic spark control error code? I've currently got the original 454 com puter in right now. Thanks for any help!

Re: 454 to 350 4l80e
 

Pretty sure the sensors are all the same, i know ive seen some one around the forums that has a 350 and found out he had a 454 computer! and he said he wasnt having any issues, no clue on the tranny though, hope that 350s got enough tourqe for the dually and whatever youre hauling!

Re: 454 to 350 4l80e
 

Alright guys swapped in a 350 computer and prom. Still doing the same thing popping out of the exhaust and if you give it more than 1/4 throttle it cuts out and dies. I have checked the timing and it is set at zero. Checked the ignition module and it tested good. This motor was running good when we pulled it out of the donor truck to put in the dually. What am i missing?
Any help or ideas would be greatly appreciated!

Re: 454 to 350 4l80e
 

First problem is these engines run at a different fuel pressure.

If you used the TBI unit from the donor 350 then it has the lower pressure regulator so the pressure could be ok. You should test the fuel pressure. If you are using the old pump that was in the truck it could be bad. Also it may have more fuel supply then the regulator in the 350 TBI unit can control.

You may run into transmission control issues with the prom and PCM from a 4L60E on a 4L80E vehicle.

Re: 454 to 350 4l80e
 

Got the 350 tbi, pcm, and tank and pump....I was trying to use the 454 pcm so it would control the 4l80e. Now I've swapped to the 350 ecu to try to get the engine running right then I'll swap back to the 454 ecu with a custom prom for the 350/4l80e.