As far as roller provisions and mechanical fuel pump provisions go, that's a crap shoot with the 638. All 880 blocks have roller provisions. There's nothing wrong with a 638 block though. There are some other small differences. 638 blocks are heavier than 880 blocks for a number of reasons. 1 being that the cylinder walls are actually longer.
I will say though, 880 was the most recent, strongest, and lightest block from the factory. It's also the only one they still use to this day.
Also, please just scrap the TBI heads now. Save yourself a lot of anger down the road.
I will say though, 880 was the most recent, strongest, and lightest block from the factory. It's also the only one they still use to this day.
Also, please just scrap the TBI heads now. Save yourself a lot of anger down the road.
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