Cascade Crew

wanarunhard · Posted: Tue Oct 24, 2006 6:59 pm Post subject: question about 2.8 intakes

ok i have a 2.8 injected motor is it possible to swap intake to carbed and stick it in my s10 blazer? i know ill have to run a electic pump cuz of no feul pump hole on the injected motor i have a carbed 2.8 with a locked up motor in my blazer

Twilightoptics · Posted: Tue Oct 24, 2006 7:03 pm Post subject:

I did the exact same thing. Took a 2.8L from an 87 maro and put it in my '84 Carbed Jimmy. Just used the block, added an electric fuel pump. Worked great.

Swear it had more power than the 4.3L jimmy I had later.

blue89 · Posted: Tue Oct 24, 2006 7:10 pm Post subject:

I agree. Its the same block, minus the mech fuel pump.

BE WARNED!

Due to differences in the years that GM phased out the externally balanced 2.8, it is advised that you keep the flywheel/flexplate with the motor it was attached to when you pulled the motor.

Easy way to tell if your automatic 2.8 is balanced internally or externally:

Internally balanced, there are 6 holes all the way around the flex plate (symetrical)
Externally balanced, there are only three holes on ONE SIDE of the flex plate, and a weight welded on to the engine side of the other side. I have pictures if you need them.

(not sure on the hole numbers, but you get the idea)

Twilightoptics · Posted: Tue Oct 24, 2006 7:36 pm Post subject:

Well the '87 injected 2.8 had an auto.... my '84 carbed 2.8 had a stick. I reused the stick and had no problems. Didn't notice any balancing issues. Maybe I got lucky.

blue89 · Posted: Wed Oct 25, 2006 7:17 am Post subject:

Wow. You lucked out. As far as I can tell (with my S10/Camaro experience) S10's had externally balanced stuff all the way past 87 (the year of my truck) while camaro's got phased in around 86. It also happens that the camaro 2.8 had the MPFI system starting in 86, while the s10 had the same TBI from 84-85(?) clean up to 89(?). I think that the camaro's got the new motors in 86 while the S10's got the leftover ext balanced till they used up stock.

I've tried to put a internally balanced flexplate on an externally balanced engine. It shakes really bad at any RPM. You'd know really fast if you got it wrong.