My 74 F250 had a wristpin come loose and gouge the cylinder about .040" on one cylinder. I have been hunting a good block and bought what I thaught was a 360 in junkyard. When I got it home tore it down and found it to be a 352. The 352 pistons and crank are in good shape, block could use a honeingbut that is in good shape. I have 2 reman heads for the 390 and a 4 barrel intake off the 390. What can I do with the 352 to make it run without it being a gutless wonder without excessive boaring? Or would I be better off getting the 390 block repaired? I never ran a 352 and dont know anything about how they perform or what can be done with them. Any imformation would help, Please.

 

I've run several 352s and several 390s. I doubt if you'll notice much difference in normal driving. Of course nothing beats cubic inches. Heavy pulling you'll know. The guys who know what to mix and match will be along.

 

Don't know how long it has been since your purchase, but I would take it back for a swap. Any FE engine from a 68-76 truck should have the 390 bore block.

As noted a 352 aint a 390 by 40 cubes, but it sits at the same table.



John

 

I have been looking for a FE block over 4 months and I was suprised to find an engine that wasnt frozen fast even though it was only a 352. Seems there arent too many FE blocks left in my area. I even have a 460 boared .040 over completely rebuilt I was ready to replace my 390 with. The only hesitation I had was that my C6 transmission for the 390 was rebuilt and I hate to waste it.

 

You can swap cases with a C6. Everything inside should be the same.



John

 

I have never tore down an automatic transmission myself how diffucult would the task be? After reading some other threads seems the best thing to do with a 352 is boar it .050 over to a 390 would you agree?

 

Why not just sleeve the 390 and do this the right way.

 

I dont know much about pressed sleaves I am looking for a long life repair would a sleaved block last as long as a stock boar in the 352? I am looking for recomdations from you guys on what would be best I was even considering the 380 build mentioned on another thread but dont have any idea where to find 390 pi rods or what that motor would be like. With only 10 cubic inches difference from the 390 would there be much difference?

 

The last sleeve I had put in an engine, a 1967 390GT with the same wrist pin problem as yours, went 78,000 before I sold the truck 8 years ago and I know the truck is still running fine because I see it every couple of weeks and the guy can't change spark plugs without help. Is that long term enough for you? Hell a lot of racing engines have sleeves from the get go.

 

A C6 is one of the easiest if Not the easiest trans to rebuild..

You can get away with hand tools except for the low reverse drum....Spring compressor needed for about 60 bucks and 20 bucks for a set of Lock ring pliers

Get a manual and a video. Autos are easy do not be afraid

Lonnie

 

A repair sleeve is as good as the skills of the installer. Choose your machine shop that do these things on a daily basis. Tell the manager, service writer, whomever, that this is no easily replaced block.

 

Thankyou all for all your help, I am sending my my old block out for repair, however I found out my supposed to be 390 4V is a 360. What needs to be changed to make it a proper 390 besides the crank and connecting rods?

 

I would leave it a 360. Use the K&B piston from a 340 chrysler and make it a 9.3:1 compression 360
you will only lose about 25lbs torque and maybe 20hp...MAYBE...over a 390 with off the shelf pistons do to better efficiency

the K&B 243 has a 1.84 ch..yet it has a raised circumference dome that they dont count that is .018 tall around the top

Add this up...360 ford

KB 243 piston...ch..1.840 + .018 dome..(not listed but a call to K&B will verify)

this will give you a ............. 1.858 CH

add...3.5 crank....divide by 2 = 1.75 crank

add.......rod ...........................6.54

You get a stack of 10.148

take .015-.020 off the deck....

see where this is going ??

way more efficient engine than a off the shelf piston for the 390 or 360 (cheap)

Usually you have almost no power loss to the 390 with this piston

the pin is .009 larger if i remember right.....but you must have your rods rebuilt and bushed already ....so your machinest can bush the rod for the larger pin
the KB 243 is full floating so no issue there..I have built 4 of these and they are Great engines and use LESS fuel than the 390 with about the same power
and a strong piston to boot !
last set I bought were about $250.00 I think

The valve reliefs are radial and work with the 360-390 head as long as your only using a .550 lift cam or less

The total volume of the KB243 is only 6.5cc

So a 9.3-9.5 compression is doalble with a 360 and the proper Cometic gasket

I know Out of the box thinking...it also works with a 390 ford..IF you mill .048 off the deck..If i remember right KB says the deck is .318 thick..and it is safe to go .195 on the deck..........................PER KB on a non boosted engine ..for a 10:1 .....390


Just my thought

Sorry for rambling on

Lonnie