: can any one point me to the right thread for this info please ?



tylersloan
12-22-10, 07:20 AM
i have a rwd 85 brougham with a HT4100 motor im wanting to swap in a Cadillac 500 c.i.d motor .

now i looked and searched this site for a build thread on this and could not find one .... i know some one has done this before there has to be at least one on here.
im also not new to cadillac 500 motors or engine swaps ive put a 48 merc flat head v8 in a 49 chevy with the original chevy trans.
ive done 350 swaps in just about every chevy car / truck from the early 60's

i have a 73 ford f100 short bed step side with a cad 500 and a TH 400 but this 85 cad has a computer and i want to have all the parts i need before i start.
im going to be using a TH 400 with the stock brougham rear end i know i know its just a puny 10 bolt but keep in mind im going to daily drive it not drag race it .
if i can find a 12 bolt on the cheap that will BOLT IN i will change it but for now it will have to do.
my question is how do i interface the stock wiring harness of the 85 with the 500 engine ? i would love to have my mpg read out still work but i doubt it will .
also is there an easy way to get the in tank fuel pump to work for a non fuel injected motor ?
i just replaced it and i dont want to have to scrap it .
thank you

YourMainParadox
12-22-10, 05:19 PM
Are you the same TylerSloan off the saturn forums?

csbuckn
12-22-10, 09:12 PM
I did a 500 swap, search "Build: Cadillac 500" and you should see it. Your mpg thing won't work. Use a fuel pressure regulator with your stock fuel pump and the oil pressure sensor from the 4100 and you should be good.

tylersloan
12-22-10, 09:44 PM
I did a 500 swap, search "Build: Cadillac 500" and you should see it. Your mpg thing won't work. Use a fuel pressure regulator with your stock fuel pump and the oil pressure sensor from the 4100 and you should be good.

Thank you so much i looked and looked i might have questions for you hope you dont mind . Thank you again im so happy now lol sorry

cosmo
12-27-10, 07:49 PM
It's fair simple. The 425 was stock in that chassis, so the mount holes should be there.
So, remove the bits you don't like, hang the bits you Do like, and buy the mounts from Cadillac to bring it all together.
The fuel pump will work, WITH a regulator, none of the rest of it will, however.
However, why not buy the TBI from a 454 Chevy, bolt it onto the 500, and mould the two distributors, using the FI bits from the 4.1 to trigger the computer. Or get an F.I. distributor for the 500. Add extra flow injectors if you like, though the low revs probably won't necessitate. Use all the sensors from the 4.1. If you're not going to get on it hard, grab a BOP TH350 with lock-up convertor, and you won't trigger a code 55 (IIRC). Otherwise just don't drive 55 (triggers the code, you see...).

Should be no problem to an old hand like yourself.

Cosmo