2.8 to 3.1

[steelbender]

I have a 86 s 10 4x4 pickup 5 spd manual with a dead 2.8

I have been given a freshly rebuilt 3.1 out of a chevy lumina (a 91 I think)
what would be involved in swapping out the 2.8 for the 3.1
I plan on ditching the multi port off the 3.1 and using the tbi off the 2.8
and If I am reading things here on the site right I will have to switch the front covers for the original v belt and serpentine pulley system to work right
due to the reversed water pump setup.

What else will I need to do?

Steelbender

[ForcedFirebird]

It's not an easy swap. The FWD block doesn't have the same mounts, and the starter is on the wrong side, along with a few other things.

[steelbender]

fix up the 2.8

Sounds like I should fix up the 2.8 instead
thanks for the input.

Steelbender

[Superdave]

Sounds like I should fix up the 2.8 instead
thanks for the input.

Steelbender

you could swap the guts over into your 2.8 block and have a 3.1...


i'd also keep the MPFI setup as it's much better than the old iron head stuff.

[ForcedFirebird]

you could swap the guts over into your 2.8 block and have a 3.1...


i'd also keep the MPFI setup as it's much better than the old iron head stuff.

I don't think so. If I'm correct, he has the small journal block and the FWD pistons would give low compression in combination with the iron heads. I started to say the same thing at first, but ended up editing the post .

[Superdave]

I don't think so. If I'm correct, he has the small journal block and the FWD pistons would give low compression in combination with the iron heads. I started to say the same thing at first, but ended up editing the post .

that's why i suggested the aluminium head stuff.. keep the compression at 8.8:1.. lol


but either way..


best bang for your buck if you want to keep it iron head, grab a 3.4 from a 95 ish Camaro and swap on your top end.

[ForcedFirebird]

He would have to fabricate some way to have DIS with the aluminum top end, the distributor won't clear the lower manifold. A 3.4 has these provisions.