dirtcrew51m

hard to say, the ecu might compensate for more air flow from the 351w.

91351

What do you mean by effect performance

scoby41

Bumping this up. Looking at putting a 351 from a '95 into my '92 stepside.

deathbypsi

I will bump one more time as I am getting ready to swap out my 94 5.0 for a 351.

was planning on using the 5.0 MAF and ecm.I figured the MAF would be able to compensate for the added air flow from the 49 extra cubes.

Planning on using my 5.0 upper...any issues with that?

My 351 is just a long block so I dont have any brackets and was hoping the 5.0 stuff will work since mine is an A/C delete.

AuroraZero

351w is a short block. 351m is a big block.

95stepside

Don't you mean the windsor is a small block? Lol

Short block means block its the block, heads and internal parts

Long block should be a complete engine from intake to oilpan

Stomper

No , short block is block and rotating assembly . Long block has heads , timing chain and cover . An engine with everything intake to oil pan is usually a used motor called a drop out .

95stepside

Well then I was taught wrong... not suprising, I did go to community college lol.

Plus my teacher was a former mopar tech...

Stomper

Okay , as far as the swap goes , The block on a 351w is approx 1 inch taller (deck height) . This pushes the heads apart therefore making the lower intake need to be wider . The motor mount locations are the same . You can bolt 302 heads right onto a 351 . You could use your stock manifolds but then you will need to modify your exhaust to line up . Every sensor on the 302 and 351 are the same if you stick with a motor of approx. the same year . If not you can put all of the sensors from your 302 onto the 351 . If you use your mass air meter your ecu will make changes needed for the extra cubes . The mass air meter measures the amount of air drawn into the cylinders and adds fuel accordingly . So from a stock 302 to a 351 you will be fine . You only run into issues if you have a highly modded motor that draws more air than the maf. can compensate for . As far as changing the flywheel , that is only due to the imbalance . This goes for the harmonic balancer as well . A 302 is 50 oz. and a 351 is 28 oz. (this only goes for stock motors as a motor could be different if it has been professionally balanced .) You must absolutely have the correct flywheel and harmonic balancer . If you get a used motor reuse the flywheel and balancer that come on it . If the motor comes out of a stickshift vehicle you need to pull the bearing out of the back of the crank .

This is a really basic swap in a truck because all of the parts are available since the trucks came with 302s and 351s . The only custom thing you have to do is make a custom cold air intake to accept your mass air meter and you will be good . Pm me with any questions , I have swapped out a ton of Mustangs and Trucks to 351s . Hell I even took the Dual over head cam motor out of my 96 Cobra and put a 306 in it with a Procharger . I used the wiring harness out of a Fox body Mustang with a few minor changes .

By the way that is my wife in the pics , only good ones of the car I could find .

Stomper

Sorry if I came off crass . I didn't mean to .