FE 360 Performance

[cleatus12r]

Oxymoron: 360 Performance

Here I am, building another engine for somebody. Whoopee.

It's a family friend, a guy a few years older than me. His dad recently died (one who gave me the 74 F250 I put a 4.6 in). The dad built a "buggy" of sorts and the son wants to restore it and have the engine rebuilt. For what it is and the severely limited use it will see, I didn't want to waste a good 390 crankshaft and set of rods......

To be continued....

[cleatus12r]

Just to throw some numbers out there since math is fun....

FE deck height - 10.170"
360 Rod length - 5.540"
1/2 stroke length - 1.750"
Piston compression height - 1.760"

Deck clearance - 0.120" in the hole. GARBAGE!

Unfortunately, most blocks (this one is no exception) need more than a 0.010" overbore for wear which puts a guy out of the realm of using a 352 piston since the largest size available is 4.060" and the 360 starts at a 4.050" bore stock. A 352 would be fine with me as the compression height of the piston is higher, affording a better quench and higher compression (1.816 CH). This WOULD get deck clearance to about 0.060" or so. BETTER.......

What is Cody the mad hatter doing? Getting Dodge 340 pistons, that's what. Certain years had floating wrist pins (like the FE) and I SHOULD be able to go an extra 0.009" on the small end bushing. If there's no balancing problems due to weight, I'll have a 0.030" overbore (4.080") with 0.040" oversize 340 pistons.....and the best part....a 0.050" deck clearance. The static compression ratio will go from about 7.85:1 to almost 9.0:1 with much better quench and I can get away with a more "sporty" cam and not completely kill the cylinder pressure.

[Power Hungry]

Originally Posted by cleatus12r

Just to throw some numbers out there since math is fun....

FE deck height - 10.170"
360 Rod length - 5.540"
1/2 stroke length - 1.750"
Piston compression height - 1.760"

Deck clearance - 0.120" in the hole. GARBAGE!

Unfortunately, most blocks (this one is no exception) need more than a 0.010" overbore for wear which puts a guy out of the realm of using a 352 piston since the largest size available is 4.060" and the 360 starts at a 4.050" bore stock. A 352 would be fine with me as the compression height of the piston is higher, affording a better quench and higher compression (1.816 CH). This WOULD get deck clearance to about 0.060" or so. BETTER.......

What is Cody the mad hatter doing? Getting Dodge 340 pistons, that's what. Certain years had floating wrist pins (like the FE) and I SHOULD be able to go an extra 0.009" on the small end bushing. If there's no balancing problems due to weight, I'll have a 0.030" overbore (4.080") with 0.040" oversize 340 pistons.....and the best part....a 0.050" deck clearance. The static compression ratio will go from about 7.85:1 to almost 9.0:1 with much better quench and I can get away with a more "sporty" cam and not completely kill the cylinder pressure.

That's quite an interesting undertaking, but I like the way you think. At the end of the day parts are parts. If they fit and line up, so be it.

Actually, it's not much different than what I've been doing with the 200 Blaster. They use a factory piston with a 72.0mm diameter and then sleeve the cylinder to match. It's not what came from the Yamaha factory, but it works and bumps the displacement up to 240cc from 200cc.

Send some pics when you can. Want to see this buggy.

[PHP Ward]

Originally Posted by cleatus12r

Oxymoron: 360 Performance

Here I am, building another engine for somebody. Whoopee.

It's a family friend, a guy a few years older than me. His dad recently died (one who gave me the 74 F250 I put a 4.6 in). The dad built a "buggy" of sorts and the son wants to restore it and have the engine rebuilt. For what it is and the severely limited use it will see, I didn't want to waste a good 390 crankshaft and set of rods......

To be continued....

I want some buggy pics as well!

-Ward

[cleatus12r]

Here you go.

[Power Hungry]

Oh, that's fun as hell!

[cleatus12r]

https://rumble.com/v1gcumf-high-comp...break-in..html

https://rumble.com/v1gdoy3-high-comp...-install..html

It's nothing special but the dang engine outruns the tachometer!

For a comparison, my dad was curious what the cranking compression is compared to a regular 360. At this elevation, 95 PSI is the max for a healthy stock 360 and a lot of the goid running ones are in the 85 PSI range. After 30 minutes or so of runtime, this one is at 135 with the other spark plugs installed (so not cranking incredibly fast). I think it's a winner!

[PHP Ward]

Sounds healthy!

And yea, that buggy does look fun.