Stihl ms 460/660 Hybrid. 469e

[Powerstroke Cowboy]

What's the blow down set at?

I'm going to call the obvious, that thing needs more stroke!

If the upper transfers are that small, you might need to keep the case compression up to be able force air through.

 

[Mastermind]

Anybody got a 500i piston to measure? Probably has a short skirt, but it’s 54mm, 12mm pin. And light.

I have one.

I'm not trying to pizz in anyones cornflakes, but isn't there an am 54mm cylinder? For the 460.

That's what I've been thinking about.

 

[NateSaw]

What's the blow down set at?

I'm going to call the obvious, that thing needs more stroke!

If the upper transfers are that small, you might need to keep the case compression up to be able force air through.

24*
I plan to raise uppers once I get over the molested slug hurdle. I still need to confirm the intake move was a good one. I don't think case compression is lacking here. I think it was airbound, and I'm confident the intake port being moved earlier, and wider, went the right direction. This last molestation of a piston needs to be reversed, before ill start fine tuning bd and such. That I'm certain of. I think by losing a ring, and cutting up into the land, I'm now dividing the upper transfer at bdc. I think in fact, that's where all the case compression is going. Tommorow I'm gonna roll the dice on the super thin double ringed slug. I'll know right away. If it'll hold together long enough to prove this slug with raised windows killed it, I can move forward. That's where my mushy brain is.

 

[NateSaw]

I have one.

That's what I've been thinking about.

When I run out of echo pistons, I'm trying your cross cylinder with 385 slug. I'll give up when I'm completely out of options

 

[Ketchup]

When I run out of echo pistons, I'm trying your cross cylinder with 385 slug. I'll give up when I'm completely out of options

You have to solve the 13mm pin problem to use 385, 288, 056 super etc.

 

[Powerstroke Cowboy]

When I run out of echo pistons, I'm trying your cross cylinder with 385 slug. I'll give up when I'm completely out of options

If you want a single ring 54mm piston with a 12mm wrist pin the dolkita 7900 big bore piston might be an option. I've got one I can pull dimensions for you if you want. I do know from top of wrist pin to top of piston is 13.5mm

 

[Woodslasher]

You have to solve the 13mm pin problem to use 385, 288, 056 super etc.

On an 066 you can run an 056 slug if you use the 056 pin bearing, Idk but it might be the same on a 460?

 

[NateSaw]

You have to solve the 13mm pin problem to use 385, 288, 056 super etc.

Then maybe a stroker IS in my future. I have a wasted 660 crank to measure. And two 461's.

 

[NateSaw]

On an 066 you can run an 056 slug if you use the 056 pin bearing, Idk but it might be the same on a 460?

460 has 15mm small end.

 

[Ketchup]

Then maybe a stroker IS in my future. I have a wasted 660 crank to measure. And two 461's.

I doubt you have the case wall for 660. Maybe if you trim the weights and rod AND the case. 36mm to 40mm is a big jump. IIRC 461 has wider weights than 460, but is still 36mm stroke. A 661 crank might squeeze in there, but I think it has wider weights as well. Lots of other cranks out there, but you’re less likely to have the same bearing sizes and the part fitment is more difficult.

We need a good spreadsheet with piston and crank measurements across many models and brands.

 

[NateSaw]

I doubt you have the case wall for 660. Maybe if you trim the weights and rod AND the case. 36mm to 40mm is a big jump. IIRC 461 has wider weights than 460, but is still 36mm stroke. A 661 crank might squeeze in there, but I think it has wider weights as well. Lots of other cranks out there, but you’re less likely to have the same bearing sizes and the part fitment is more difficult.

We need a good spreadsheet with piston and crank measurements across many models and brands.

@Dolkitafreak . Ethan you build spreed sheets and wicked race saws... What's your take on all this Tom-foolery?

 

[Rich Fife]

You can use the 288 bearing to run that piston in an 066....but it needs a couple of bushings on either side of the rod to keep the rod centered. I make those from brass.

I make spacers out of medium carbon steel, torch and quench them in a solution to harden them. Then I toss them on a precision stone and make them smooth as glass.

 

[Rich Fife]

Anybody got a 500i piston to measure? Probably has a short skirt, but it’s 54mm, 12mm pin. And light.

I have a few oem 500i pistons. (I'm reading the comments and commenting as I go along).

 

[Powerstroke Cowboy]

460 has 15mm small end.

Ouch. That's very limiting.

 

[NateSaw]

If you want a single ring 54mm piston with a 12mm wrist pin the dolkita 7900 big bore piston might be an option. I've got one I can pull dimensions for you if you want. I do know from top of wrist pin to top of piston is 13.5mm

Whats the stroke on a 500? That'll clue to height. I'd imagine it's 40mm the way they run. Idk. But I doubt it's tall.

 

[Ketchup]

Whats the stroke on a 500? That'll clue to height. I'd imagine it's 40mm the way they run. Idk. But I doubt it's tall.

Nope. 34.6mm. IIRC. Thus my thinking the skirt is short. But it’s a Mag piston. That would be cool.

 

[NateSaw]

Nope. 34.6mm. IIRC. Thus my thinking the skirt is short. But it’s a Mag piston. That would be cool.

Won't work then.

 

[redline4]

I doubt you have the case wall for 660. Maybe if you trim the weights and rod AND the case. 36mm to 40mm is a big jump. IIRC 461 has wider weights than 460, but is still 36mm stroke. A 661 crank might squeeze in there, but I think it has wider weights as well. Lots of other cranks out there, but you’re less likely to have the same bearing sizes and the part fitment is more difficult.

We need a good spreadsheet with piston and crank measurements across many models and brands.

@Dolkitafreak . Ethan you build spreed sheets and wicked race saws... What's your take on all this Tom-foolery?

@freucrew made a nice crankshaft dimension template and had posted it on here. I think it was in his Solo stroker build thread.
Speaking of that slacker Dave, I should shoot him a text, I haven't heard from him in a bit now..

 

[NateSaw]

@freucrew made a nice crankshaft dimension template and had posted it on here. I think it was in his Solo stroker build thread.
Speaking of that slacker Dave, I should shoot him a text, I haven't heard from him in a bit now..

Hi Ed! Thanks! When I get home it's back to being an adult. I've fugged around enough. Piston #3 will go on the lathe.

 

[Powerstroke Cowboy]

We need a good spreadsheet with piston and crank measurements across many models and brands.

Sounds like you should start a thread. We've got enough members and builders here to supply the data. I bet with as many saws as some see in a year the data could come in quickly. It doesn't take much time to collect it.

We need a standard template for the crankshafts and pistons to keep everything as organized as possible. Sounds like @redline4 might have a lead on the crankshafts template.

I've got a couple different saws torn apart right now that I could collect the crankshaft and piston data on. I was going to do it anyhow just for future reference if needed. Ive been wanting to build a stroker/hybrid out of a smaller saw hence the reason for starting to collect information. I already have all the dimensions for one saw wrote in a notebook.