Wiseco Piston and Hybrid Ceramic Bearings from Dominant Saws for 372XP
- Thread starter blsnelling
- Start date
Help Support Arborist Forum:
IMHO, popup vs flattop is much ado about nothing. Here are two 661s built identically, except one has a popup and one a cut squishband. The one with the popup holds more RPMs in the cut, even with a heavy load. Add to that, that I had forgotten to add bar lube to the saw with a popup. Yes, I pulled a Wiggs, lol 
Many a guy has had that problem with Wiseco pistons. The nick name for them is Seizco.
I really like them. They are tough as nails and when clearanced correctly work great. The also will no crack a skirt like a cast piston if the p to c clearance opens up from wear.
IMHO, popup vs flattop is much ado about nothing. Here are two 661s built identically, except one has a popup and one a cut squishband. The one with the popup holds more RPMs in the cut, even with a heavy load. Add to that, that I had forgotten to add bar lube to the saw with a popup. Yes, I pulled a Wiggs, lol
Is this a drop in or will you have to cut the base for ideal squish? I was just thinking of it doesn't work and you had to go back to a flat top.
IMHO, popup vs flattop is much ado about nothing. Here are two 661s built identically, except one has a popup and one a cut squishband. The one with the popup holds more RPMs in the cut, even with a heavy load. Add to that, that I had forgotten to add bar lube to the saw with a popup. Yes, I pulled a Wiggs, lol
I'd much prefer a uncut piston with a machined squish. One area I think saw builders are missing the boat and one that nets pretty large gains is adjusting the angle and width of the squish band.
I believe this piston is intended to be a drop-in. I don't think this 1/2 finless jug I have has been touched, so I will test that out.
Not much you can do about the width.
If that's the case then I'd give one a try.
http://www.ebay.com/itm/Dominant-Sa...-50mm-Husky-/121770823546?hash=item1c5a1b4f7a
"They are direct replacement and significant upgrade to the OEM 50mm piston. Single, thin 1mm, chrome ring, lighter weight 7g less, and lower thermal expansion (higher silicon and only Wiseco know the numbers) add up to a piston many times better than OEM or other replacements. These have domed crowns for boosted compression and improved in cut rpms."
"They are direct replacement and significant upgrade to the OEM 50mm piston. Single, thin 1mm, chrome ring, lighter weight 7g less, and lower thermal expansion (higher silicon and only Wiseco know the numbers) add up to a piston many times better than OEM or other replacements. These have domed crowns for boosted compression and improved in cut rpms."
super3
Addicted to ArboristSite
You need to catch up on what's being done lately.
The deeper the cut, the wider it gets.
Not easily, granted. It would seem to me you could set squish angle to your desired measurement, then come in with a different tool and set the width and cut the chamber to more of a hemisphere shape.
Then you defeat a big part of why you cut the squishband, increasing compression. We'll save this for another thread though. Yes, I know I started the derail, lol.
I would find it very interesting if this piston had both a higher silicon content and was lighter than stock. Wiseco pistons have always been heavier than the stock pistons they replaced IME. Not that that's a bad thing. They take abuse that will crack a stock piston in short order.. However they don't seem to deal with heat as well and melt easier than a cast piston.
I will definitely put it on a scale. It feels heavier in the hand.
Granted, and testing would have to be done to see if the trade off was worth it. Maybe the best thing woukd be a popup and chamber like I suggested?
I have personaly never seen a Wiseco that's lighter than stock. And I have used them quite a bit, including their single ring race pistons.
backhoelover
Free service manuals and service tool info
all this talking about saws 
Moparmyway
Its just a saw
- Joined
- Dec 2, 2012
- Messages
- 2,481
- Reaction score
- 3,399
Brad, your pop-up 661 is simply astonishing !!
Great job !!!
Any idea what RPM's she was turning
Please dont forget to make that new thread ................ i will be watching for it !!
Great job !!!
Any idea what RPM's she was turning
Please dont forget to make that new thread ................ i will be watching for it !!
No. My tach doesn't work on this saw.
