Motor Swap

[Lscam580]

i just bought a 306 short block for $100 and I have all the receipts for parts with it. Been rebuilt and never fired. The block is out of a pickup. Will this work in a mustang? The crank and rods are from a truck.

 

[7991LXnSHO]

I think if you dress it with all the external Mustang parts, it will be fine. If they did good machine work, you got a steal.

 

[old_blue]

should be fine. 302 doesn't change that much over the years and are pretty much interchangeable without too much hassle. Only concern is if it is a roller motor or not. What are your plans for it?

 

[Lscam580]

I called auto parts store and they say that the crank from mustang and truck are different because truck doesn't have cylinder #5 oil slinger. But it's a 5.0 roller motor with the roller lifters,dog bones,and the spider tray. Ran the # on the Pistons and comes back as a "pro true street forged weisco flat top piston. " 64 cc head comp ratio is 10.2-1.and the receipt says the same. Some I'm fairly confident that all is true to what the seller says. I'm just wondering if I should pull the pan and use plasty gauges to check mains and rods to see it it's ok

 

[7991LXnSHO]

Unless it is a Fox pan, it is getting pulled anyways. PlastiGauge is cheap and will make you feel better. Go for it.

 

[jrichker]

The truck cams and 5.0 HO mustang cams are different. Truck cams are ground to produce more low RPM torque and less high RPM HP. Mustangs run best when the HO cam is used. Swap the 5.0 HO cam into the truck block and you will be good to go.

 

[Chuckman]

I called auto parts store and they say that the crank from mustang and truck are different because truck doesn't have cylinder #5 oil slinger. But it's a 5.0 roller motor with the roller lifters,dog bones,and the spider tray. Ran the # on the Pistons and comes back as a "pro true street forged weisco flat top piston. " 64 cc head comp ratio is 10.2-1.and the receipt says the same. Some I'm fairly confident that all is true to what the seller says. I'm just wondering if I should pull the pan and use plasty gauges to check mains and rods to see it it's ok

the only internal difference between the stock mustang and truck/non-ho short blocks is the pistons, h.o. uses a factory forging, while the others are just cast. theres no "#5 oil slinger" in either of them. both are balanced to 50oz too, though not all builders really realize this and will try to do the early-style 28oz balance (happens more with guys who mostly build chevy motors, not common, just something to watch out for).

outside the short block (and heads, those are also the same casting though springs might be different), almost everything else is different: oil pan and pickup, cam as mentioned (and theyre not a straight swap either, truck is still a flat-tappet), intake manifold, and front dress. as long as you have these h.o.-specific pieces (or better aftermarket parts), youre good to go.

double checking bearing clearances and the overall condition of the engine is a good idea any time you buy a motor.

 

[revhead347]

If it's all good, then it's a steal. Flat top piston in a stock deck height block with 64cc heads is 9.0:1.

Kurt