351 to a 302 swap

Post by **kid2** » January 9, 2007, 9:15 pm

Ok guys I am getting ready to swap a 302 into a neighbors 77 or 78 4x4 pickup. Are the bell bolt patterns and blocks the same and will the 302 bolt up.Will the flywheel from the 351 swap over to the 302 or is it different. His 351 is about to give up and he has a good 302 setting in his garage he wants to use. He wants to rebuild the 351 to put back in later so we dont want to have to change alot if we dont have to. Let me know what we need to do...........Kid

jimbob1021 · Post by **jimbob1021** » January 9, 2007, 9:25 pm

the 351 w is the same as a 70s 302 the 351m is not the same it has a larger bolt prttern for the bellhousing............jim

jakdad · Post by **jakdad** » January 9, 2007, 9:41 pm

The 351M C-6 has the same bolt pattern as the FEs so will require a trans change if it is automatic. I don't know about the standards.

banjopicker66 · Post by **banjopicker66** » January 10, 2007, 11:55 am

Uh-oh, Jim.

The FE bell pattern is unique. Only FE engines will bolt to it, the 352, 360, 390, 406, 410, 427 and 428 being the most common in the FE Family.

The 351M-400 bell pattern is the same as the 385 Family of engines, the 370, 429 and 460.

The Windsor family is the 289, 302 and 351W. There are others of lower cubic capacity, but they came earlier then '65, and are more of a purist's or collector's interest than anything else.

If I remember correctly, the 240 and 300 inline 6 share the same bellhousing bolt pattern as the 302 and 351W.

jakdad · Post by **jakdad** » January 10, 2007, 12:00 pm

Banjo, you are right! The small blocks and Clevelands use the same not 351M-400.
My bad
:oops:

banjopicker66 · Post by **banjopicker66** » January 10, 2007, 12:29 pm

So the question remains: Is the 351 in question a 351M/ or a 351W?
To summarize, if he is pulling out a 351M, the 302 won't match the existing bellhousing.
It will, if he is pulling out a 351W.

Satinblack · Post by **Satinblack** » January 10, 2007, 1:52 pm

Yes 351C is same as small block 289/302 etc. Yea would help to know which 351 it is?

71 LONG BED · Post by **71 LONG BED** » January 10, 2007, 2:14 pm

The 351M was developed in 1975 to replace the 351C for use in large passenger cars. The 351M/400 engines were used in light-duty trucks starting in the 1977 model year. Assuming the 351 is original to the truck, I don't think the 302 will be a direct bolt in.

ICEMAN6166 · Post by **ICEMAN6166** » January 10, 2007, 2:26 pm

IMO ,the 351M/400 is best used at the end of a chain on your boat.
never had one i liked.
i replaced one in a 78 f100 4x4 with a 429 and was amazed at the improvement.

didgeytrucker · Post by **didgeytrucker** » January 11, 2007, 2:55 pm

I would bet money the 351 in the '77 4x4 is a 351M. The 302 wil not bolt in directly. The engine mount towers might work. I know the transmission will not.

If the valve covers match on the two engines the swap will work. If the valve covers are different the swap will not work.

Tracy

FORDMANLCRACKEL · Post by **FORDMANLCRACKEL** » January 13, 2007, 8:02 pm

didgetrucker is correct. My 66 is sitting on a 77 chassis it had the 351m. the motor towers will work on the 302 but you will need the bellhoiusing for the 302. The bolt patterns are different than the M. The bellhousing from a 240 to 351 W will work. Get the cast iron not the alum. My bell came from a 240 three on the tree. Flywheel will interchange for 302, 351C and 351W. you will need the one with 164 teeth. All the above is for four speed with granny first gear. If it is an automatic you will have to change the trans. 429 or 460 will bolt right in if its an automatic and the gass milage wont be any worse.

Lonnie