Will a 351w bolt into a 71 mustang that had a 302!

7173Mustangs.com

Help Support 7173Mustangs.com:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

maximd30

Member
Joined
Feb 11, 2014
Messages
24
Reaction score
1
Location
Santan Valley, AZ
My Car
71 mustang coupe
Okay so I just pulled my stock 302 out of my 71 coupe. Will a 1989 351w bolt right in? And fit with out any problems (engine mounts exc) PLEASE HELP I NEED TO KNOW BY TONIGHT

 
The 302W and 351W have the same mounts. The frame mounts on the car are the same; you'll want to have new motor mounts when you install the motor, anyway. The bell housing is the same. The 351W and 302 is pretty much the same block, except the 351W is just a little taller.

Good luck with your swap.

 
The 302W and 351W have the same mounts. The frame mounts on the car are the same; you'll want to have new motor mounts when you install the motor, anyway. The bell housing is the same. The 351W and 302 is pretty much the same block, except the 351W is just a little taller.

Good luck with your swap.
also 351w is a little wider than 302 (1.5 inches) I think you will need front sump oil pan on 351 if it doesn't have it.

 
Thanks bro


What about balancing the fly wheel??? And the harmonic balancer ??

 
Last edited by a moderator:
The earlier 302's had a 28 oz imbalance, same as all of the 351W's. In 1981, the 302's switched to a 50 oz imbalance. The 89 351W will be serpentine drive on the font end, so you may have to modify accessories up front. That 89 motor will have fuel injection, too, so you'll need an intake to mount a carb on.

 
Oh yikes... Not trying to thread-jack, but you can't put a 71 302 flex plate on a 97 302? The balancing is different???

 
The balancing may be an issue but except for that it's plug and play. Mine had a 302 and has a 351w now. The swap was pretty straightforward.

Motor mounts fit.

Hedman make shorty headers for that exact application. I have them now but in the beginning I used the long tube headers that I had with the 302.

 
Ok the oil pan I took off the 302 is a front sump but it's not fitting on the 351 because the crank is to big on the back. Am I going to need to get a different oil pan? Any suggestions?

 
As I said in the other thread the oil pan is 351 specific. A 302 pan won't fit although I don't remember what exactly the difference is.

You need a front sump one.

 
-Distributor is going to be different. 1/4' shaft vs 5/16" shaft

-Intake manifold is wider on the 351

-Oil pan, quite different

-Front engine brackets may not bolt up, Taller deck height has holes off by about 1/2" if you try using 302 brackets

-Headers may not fit anymore

-Timing cover may need to be swapped to utilize dipstick and mechanical fuel pump. Verify timing gears have the pump eccentric installed if required. Then verify if the timing marks are in the same location as well as the correct rotation water pump and radiator hose inlet.

 
Last edited by a moderator:

Latest posts

Back
Top