i was wondering if an 87 roller 305 would work in an 84 305 trans am? the 87 motor is out of an 87 grand prix. the original motor in the trans am spun a bearing and the 87 motor its complete and with 50k original miles. would this be a bolt in replacement of are there things i'm goingin to need to change with the computer and wireing and stuff? i i'm asking because i'm planing on getting this car in a trade but i need to get it running rather quickly, i hope its just a drop in and go.

 

The '87 is a V8?

 

yes another 305.

i belive its a roller motor based on this thread
https://www.thirdgen.org/forums/tech...light=lg4+prix

i dont know how many diffrences there are but it seems about the same assumeing there both lg4's.

 

I wouldn't make any blanket statements about non-3rd gen engines.

For instance, the G-body L69 was different from the f-body L69. '88-'95 truck TBI had flat tappet lifters.

Two ways to find out without pulling the intake manifold: 1) Pull the distributor and hope you can see down in the lifter valley whether or not there is a spider in there; 2) Pull a valve cover and rocker arm, measure the length of the pushrod - short = roller, long = flat tappet.

 

ok then assumeing it isn't roller it would bolt right in right, but if it is roller would it work or would changes need to be made?

 

Either way, it will bolt in. The changes you can assume are one-piece instead of two-piece rear main seal, centerbolt valve covers, and intake manifold center two mount bolts on each side at 72 degrees instead of 90.