I have been told that the 2.8 is "weak" in terms of it's construction; and that the 3.1 or 3.4 is a better engine.
What exactly has been improved on the larger engines? I know on the 3.1 and 3.4 there is a larger crank, and the bore is larger on the 3.4; are there any differences in terms of the block strength?

Would a bored 2.8 w/ a 3.4 crank have the same strength as a crate 3.4?

Thanks
Patrick
85 Cherokee 2.5L
Looking for info on a 3.1/3.4 swap

 

2.8? Weak??

Youve been hanging around too many V8'ers. Its a tough little engine and is very respectable for a V6.

 

I meant weak as in the strength of the block.
I've talked to a lot of people who have the 2.8 in Cherokees (original equip in 84-86s) who have had problems throwing rods and the like. I figure this may bea problem with the 2.8 crank and the 3.1/3.4 crank would sole it. Are the blocks the same construction for all the 60 degrees?

Thanks
Patrick

 

Odd... our Fbod 2.8's have been known to go 400k miles without a rebuild... during the '86 model year the crank journal size was changed.. that's about the only block change I know of though.

------------------
'86 Camaro SC, black /w silver racing stripes
2.8l MPFI/700r4
In search of new v8 engine & transmission
MSD coil, Accel 8mm wires, SplitFire plugs, Gabriel hijackers

 

So an 86+ 2.8 block w/ 3.x internals (crank/bore) should work as well as a crate 3.x? That could save me some $$.

-Patrick