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Wiseco ring gap issues TOO BIG or GO WITH IT?

Ricerdude

Proven Member
16
1
Sep 19, 2003
Idaho Falls, Idaho
A few years ago I built a 6 bolt with Wiseco 10:1 HD pistons. I was setting the block up for 30+ psi, and to be mainly street driven. I requested a .004" PTW clearance from the machine shop.

I set the rings at
TOP: .020"
Second: .024"

The pistons ended up failing due to a MFG issue and Wiseco stood behind them and send me a new set. BUT I had to re-hone the block. When I got the block back from the machine shop it measured 3.3683" putting my PTW to 0.0045. From what I have read this is not issue at all.

I order Wiseco 85.5xx rings, the top has plenty of meat to file/fit, the second has a 0.027" gap from the box. I don't really want a gap that big.

I called Wiseco and they send me 86XX rings, and never answer my question on the ring being a different diameter than the cylinder and if this is a problem. I file down one of the second rings just enough to get rid of the overlap and with my flashlight I can see a TINY bit if light between the cylinder wall and the ring ONLY by the gaps.... now what.

I call Total Seal, they are less than no help, I wont be dealing with them again if I can help it.

Now what are my options, I am sure someone else has gotten into this territory.

Thanks for the advice.
 

DSMPT

DSM Wiseman
2,055
1,614
Jun 12, 2014
Japan / Mexico, Arizona
I order Wiseco 85.5xx rings, the top has plenty of meat to file/fit, the second has a 0.027" gap from the box. I don't really want a gap that big.
That happens often when you have loose PTW clearance. It already has wider gap than your target gap on 2nd rings when out of box without filing. You would have slightly more blow-by gas but usually you can use them without any issue.
I called Wiseco and they send me 86XX rings, and never answer my question on the ring being a different diameter than the cylinder and if this is a problem.
Generally speaking, usually you can go 0.25mm over size rings without any issues but many aftermarket piston manufacturer don't have ring set for 85.75mm. Because they use the same piston ring manufacturer and the ring manufacturer don't supply for 85.75mm (.030 over). That's the reason why there are 85.00mm/85.25mm/85.50mm/86.00mm off the shelf kit but 85.75mm kit. So if your piston kit/cylinders are 85.50mm and want the 2nd ring gap tighter, then your option would be only the 8600xx rings.

I file down one of the second rings just enough to get rid of the overlap and with my flashlight I can see a TINY bit if light between the cylinder wall and the ring ONLY by the gaps.... now what.
What you did is a light tight test by using a flashlight. Less light you see = more conformity to cylinder wall.
I think you would be fine either with the 8550xx or 8600xx rings, 2nd rings are more for scraping oil. I have used the 8600xx rings instead of 8550xx and in my case It was just fine.

8550xx rings would allow you to have better conformity to cylinder wall but you would have wider 2nd ring gap.
8600xx rings would allow you to have tighter 2nd ring gap but maybe a bit less conformity to cylinder wall.
 

1990TSIAWDTALON

Moderator
9,292
5,086
Nov 14, 2013
Independence, Kansas
^^^
Agreed
 

Ricerdude

Proven Member
16
1
Sep 19, 2003
Idaho Falls, Idaho
Thank you for your response.

I am leaning towards the 86mm rings and just setting them at the gap I want and going with it. I figured I wasn’t the first one to encounter this situation. I guess the breakin time might be a tad longer but using a thinner oil with detergent may help them seat quicker.

Thanks
 
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