I'm looking at a 56 f100 someone converted to 350 chevy (idiots!). Can I easily convert it back to a y block, or is it a big hassle?

 

It depends on how much they have cut out?

Do you still have these corssmembers left?

http://1.bp.blogspot.com/-Ku1sU39oQb...0/DSC_0395.JPG

 

Thanks Jim for responding,

Yeah, typically the guy bought the truck already converted. so what's there is it. Whatever I do will require me putting it back to normal. My main concern is what may have been cut out to do the engine swap. If it's just a matter of putting the original mounts back in, that's doable, but if it was all chopped up, I don't think I want to tackle it.

steve

 

Hi

do you still have the beam front axle?

Check underneth to see if you can find the crossmembers that you see in the picture I attached.

Have the framerails been boxed? ie instead of a u-shape, they might have placed a steel plate in the inside of the frame rail giving u a rectangular shape instead

 

The y block in these trucks has one front (timingcover) and 2 rear (bellhousing) motormounts. So you need to find out if they have cut out these two Crossmembers that you see in my picture above.

Its likely they have added a crossmeber between these two for the sidemounts for the Chebby, and probably they have removed of cut away the rear crossmember (the one just under the end of the plywood) and replaced that with some tubular bolt on that fits your gearbox.

Remowing the rear engine crossmember on these truck makes the front cab frame members (outside) to sag and you can get a missalignment on the whole front sheetmetal.......
The rear orignial crossmember holds the rear of the engine and trans and also keeps the framrail together and straight, preventing the front cab members to sag

 

It's probably very doable. You'll really need to take some pictures and let us see how the PO put the 350 in. If they bought a mount kit many were bolt in and can easily be removed. I doubt they removed the front crossmember because that's where the radiator mounts and all the sheet metal hangs off of. The real question is the rear mount between the front cab mounts. If it is there, and in tact, you're Golden! Keep in mind there is not a transmission cross member on these old trucks. The tranny hangs off the back of the bell housing. That's why the crossmember between the cab mounts is so important.

 

I have a 1981 F100 that I love. Single rail four speed Overdrive Transmission on floor. Smaller 8" flywheel. If I tried to upgrade what could I get a 302 out of (the newest) from a junkyard to upgrade to say Fuel injection? I am getting old and don't want to crawl around under the hood so much. I search to see what 302 out of what vehicle would be the most reliable, always start, not breakdown engine to buy to put in what I have?

 

When considering the feasibility of changing back to a Y block, be mindful of what you have and what you need as a donor engine package. Cars and trucks use different engine mounting.
Just a FWIW but is the rest of the truck still entirely stock enough to justify going back to a Y block? Chevy makes a good reliable engine and if the swap is done correctly makes a good combination.
What do you envision for the truck? Driver, concourse correct show truck, or other?

 

They could still have removed the front motor crossmember. It s not the same as the radiator and sheetmetal is mounted on...

 

Correct the v-8 powered 53-56 have an additional cross member for the front mount

The 6 cyl mount attaches to the radiator support crossmember

 

Interesting, yet another day with increased knowledge.....

 

You need to have these two cross members. The front to mount the engine, radiator support and front clip to. The back one to mount the rear motor mounts to.



I know my back mount is cut. The PO did it so they could remove the automatic without pulling the engine.

OBTW this was a 6 cylinder.

 

Hm.... Cut to pull the trans..... That was creative......

 

I may not be the sharpest knife in the drawer when it comes to this stuff, but cutting a crossmember, wow!

Here are pictures of the 8 cylinder crossmembers.

 

No, no, no. That'll never work, Harrier.. Those are WAY TOO CLEAN!