difference in early and later sbc???

[d14099]

hi thanks for reading i have an 88 chev 5.7 with 262000 time for a heart transplant i have an 80-85 sbc what are the differences will the front motor plates and serp belt work on this engine or do i need the old set up to make this work. also the 88 is a tbi and the other is naturarlly aspirated q jet set up, any help appreciated any ideas

[MagicRat]

In '87 the intake manifolds changed, so the later intakes will not fit on a pre-87 heads and vice versa.

Also, possibly the serpentine water pump spins in the opposite direction than the old pump arrangement, so if you keep the serpentine belt set up, you also need the serpentine pump.

IMO sell the older engine and rebuild the '88. It's a better engine anyways.

[silicon212]

Originally Posted by d14099

hi thanks for reading i have an 88 chev 5.7 with 262000 time for a heart transplant i have an 80-85 sbc what are the differences will the front motor plates and serp belt work on this engine or do i need the old set up to make this work. also the 88 is a tbi and the other is naturarlly aspirated q jet set up, any help appreciated any ideas

The flexplate is not interchangeable - the earlier block has a two piece rear main seal with a counterweight on the crank flange - the later block has a one piece seal with the counterweight on the flexplate.

MagicRat is correct about the water pump - you will have to use the water pump for which your belt drive is designed. The serp pump does rotate reverse of the crank, while the old V-belt drive rotates with the crank.

You will get better economy and better midrange and low-end performance using the centerbolt, swirl-port heads on the '88 engine. The two center bolts on each side of the intake on these heads are situated at 72 degrees vs. 90 degrees on the outside bolts (or all bolts on the earlier heads), so the intakes are not interchangeable.

As MagicRat states, the '88 is all around the better design. I went from 492 heads (older style camelback/double hump 'fuelie' heads with accessory bolt holes), to a set of 193 heads (the heads likely on your '88 5.7) - lost nothing down low, yet increased the midrange at the sacrifice of top end ... face it, who's going to drive a '88 Caprice at WOT all day? ... economy went from 12/16 to 15/24 just for the sake of the head transplant.

[d14099]

hey guys
thanks for the info, can the 88 heads be put on the 85 short block??
also are there any diferences in the front of the block, will the accessory plate that holds the p/s and the alt. and the a/c from the 88 fit the 85???

[Blue Bowtie]

The heads will bolt on with no problems.

The '88 passenger car block will accept a factory roller cam and lifter retainer plates, while the earlier block will not.

The accessory holes are in the heads, and holes in the front of the block have been the same since 1957 (except for LT1s).

[d14099]

hey man thanks for the info i feel a little better about this now its just a matter of keeping the fuel injection or going carb, with std electronic ignition and no computer

[d14099]

Originally Posted by d14099

hi thanks for reading i have an 88 chev 5.7 with 262000 time for a heart transplant i have an 80-85 sbc what are the differences will the front motor plates and serp belt work on this engine or do i need the old set up to make this work. also the 88 is a tbi and the other is naturarlly aspirated q jet set up, any help appreciated any ideas

Originally Posted by Blue Bowtie

The heads will bolt on with no problems.

The '88 passenger car block will accept a factory roller cam and lifter retainer plates, while the earlier block will not.

The accessory holes are in the heads, and holes in the front of the block have been the same since 1957 (except for LT1s).

so in order to make this combo work i have to use the older style lifters and rockers, will they fit on the 88 heads
thanks
david