360 to 390 conversion questions

[fomocoguy]

I know this subject has been gone over a number of times here, but I couldn't find specific answers to my questions by searching, so if some of you FE gurus could enlighten me it would sure be apprieciated!

So in my search for a power steering pump and pullys I ended up with an 80k mile 360 out of a 76 F100. I'd like to do a budget build on it and turn it into a 390. The local oreilly auto parts sells a complete crank and bearing set for $208, so I've got the crank covered. I'd like to use the stock heads but achieve a cr of anywhere from 9.0:1 to 9.5:1.

The question is what rods and pistons should I look for? I read somewhere that I could use my stock 360 rods and find some 390 truck pistons, but will the rods hold up? I'm trying to use as much as I can of what I already have but I want it to hold up. Intake and cam choices are already covered.

Also, what's with the trick with the holley jet dropped in the oil supplys to the heads? Thanks guys!

EDIT: Do you think these would do me any good? http://cgi.ebay.com/ebaymotors/Mercury- ... ccessories

OR these: http://cgi.ebay.com/ebaymotors/360-390- ... ccessories

[Doug Comer]

PM sent.

[convincor]

Also, what's with the trick with the holley jet dropped in the oil supplys to the heads? Thanks guys!

http://www.carcraft.com/techarticles/cc ... tures.html
Gess Ford sells restrictors that thread in. .060 for race .090 for street.
http://www.gessford.com/cobraparts/fheads.htm
I tapped for a set screw in my Edelbrocks, drilled with a .090 hole.

[fomocoguy]

Well I may have some 390 rods lined up, but I'm still not real clear on the pistons. What is the difference (if any) between 390 truck and 390 car pistons? If you buy aftermarket flat tops does it matter?

Also, does anybody know what cc the heads would be on a 1976 360?

[convincor]

piston pin height is different between the car and truck
car is 1.759"
truck is 1.660"
Truck piston is further below the deck therefor lower compression.
As for the head volume, I believe it to be 74cc.
Aftermarket flat tops are fine. You'll be at about 9-1/2 to 1

[fomocoguy]

piston pin height is different between the car and truck
car is 1.759"
truck is 1.660"
Truck piston is further below the deck therefor lower compression.
As for the head volume, I believe it to be 74cc.
Aftermarket flat tops are fine. You'll be at about 9-1/2 to 1

Thanks! The trw's in my first post show 9.36:1 with 74cc heads. Perfect! Now I'm starting to get a litlle excited about this...

[James72]

I bet one of these would work nicely
I'm also converting a 360, it's going to be a fun build, I was lucky enough to get a spare 428 crank and rods when I bought a bunch of FE stuff locally

http://cgi.ebay.com/ebaymotors/ws/eBayI ... OTORS:1123

[fomocoguy]

If anybody knows the hard facts on what parts I can use it would really be apprieciated. I saw a post talking about using a 390 crank and 360 pistons; if I can use my existing pistons and bring them up to deck height with the 390 crank and rods that would be awesome. Any thoughts?