Husky 455 to 460 upgrade and porting

[morbius18]

This is what I've done to mine. I raised the exhaust 2-3 degrees to increase blowdown and opened the exit. Widened the transfer and blended the plate that sticks into the transfer. I opened and squared the intake and lowered it 2 degrees. I didn't touch the stratos as they are restricted by the tiny square holes in the intake manifold. I also raised the lower transfer opening. I cutout the strato part if the piston when it is at tdc to not restrict the flow.

 

[mettee]

Looking good.

I haven't had much time lately to get back to the saw. But I will. Looking forward to seeing how it runs.

 

[morbius18]

I port matched the muffler, shield and gasket as well as removed the spark shield, cut 2x 3/8" holes into the internal baffle part that separates front and back of the muffler. I also cut gills.

I finished mine up and discovered the spur is 3/8". I've only got small mount husky bars and chains in .325. It was pretty wore, so I bought a rim drive one and am waiting to finish it up.

Compression is pretty nice, even though I raised the exhaust port to increase blowdown.

 

[mettee]

I picked up a husky deflector for mine so I can dual port it. I havent added it to mine yet.

But your progress looks great.

Port that intake out.

 

[morbius18]

I picked up a husky deflector for mine so I can dual port it. I havent added it to mine yet.

But your progress looks great.

Port that intake out.

Are you talking about the intake port or the manifold? I opened the intake up quite a bit. I also opened the edges of the rubber manifold where it mates to the cylinder. I widened the intake, lowered it and squared it off. I try not to hog an intake out on a strato without proportionally opening the strato. The tiny size of the manifold squares on the stratos that meet the cylinder limited how much I felt comfortable doing.

Numbers I ended with:

Intake: started at 71°, lowered to 74°. Widened and squared

Exhaust: started at 104°, raised it to 101°
Widened

Transfers: stayed at 117°, widened towards intake, blended plate lower

Strato: stayed at 91°

Blowdown: started at 13°, increased to 16°

Squish: .034", clamshell

 

[mettee]

 

[morbius18]

I did some, but the other side was the real bottleneck.

 

[mettee]

Its the sharp lips on the two inlets that will kill it.

 

[morbius18]

I picked up a husky deflector for mine so I can dual port it. I havent added it to mine yet.

But your progress looks great.

Port that intake out.

You got a part number for the deflector?

 

[mettee]

503078301

https://m.ebay.com/sch/i.html?_from...84.l1313.TR5.TRC0.A0.H0.X.TRS5&_nkw=503078301

 

[usmcbuckwild]

Is this saw done yet?

 

[morbius18]

Is this saw done yet?

Mine is. It ran better than stock, but I basically wasted my time. My 346xp with similar work done spanked the 455. I sold the 455.

Its too heavy and under powered for me to really use. I have a 346xp, a 550xp, a 562xp and a 372xp.

 

[usmcbuckwild]

Mine is. It ran better than stock, but I basically wasted my time. My 346xp with similar work done spanked the 455. I sold the 455.

Its too heavy and under powered for me to really use. I have a 346xp, a 550xp, a 562xp and a 372xp.

I know they are under-powered slugs; I was busting @mettee ’s stones is all.