Can I just through a 3.1 crank/pistons into a 2.8, using 2.8 rods?

Just what's the deal with the 3.1 into a 2.8 thing?

Also, if that's possible, I'm thinking a .030" overbored 2.8 running a 3.1 crank/pistons might not be a true 3.4, but it should be fairly interesting!

 

actually shouldn't come out anywhere near 3.4L's more likely then not u'llend up with a 3.1L. For some reason, i read that the bore on the 3.1 was something like .030 over the 2.8l's, plus the adition ofthe crank, gave 3.1L. at most, you might be thinking 3.12 L give or take a lil' .

 

the 2.8 and the 3.1 have identical bore, it's the stroke that makes the difference. if you bore a 3.1 .030 over you get like a 3.23 or something like that, i have heard of people going .060 over with these things but i know that that is pushing it a little hard. i would suggest finding a 3.1 block (since you'll have the motor out of the car) because gm improved the crankcase on the 3.1 over the 2.8. You can seriously only push these cars so far, then you get into big problems and you will have a crank shaft laying on the ground.

 

Actually the 2.8 had 2 different cranks. One had smaller main bearings(67MM?), and 2MM shorter stroke. the other 2.8 is identical to the 3.1 crank in every respect. The 3.4 has a longer stroke. 1. something MM I think it is.