Kenny_Kline
Well-known member
What does everyone do when replacing rings on wiseco pistons? I only need the top ring. The other 2 rings are fine still new.
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Piston ring replacement suggestion
- Thread starterKenny_Kline
- Start date
EMX5636
Well-known member
I take it one got broken? I haven't tried in a few years, but last time I got a replacement ring, they only sold them in a set for 1 piston (all three rings for 1, not a set for all 4 pistons). Give them a call or email and order it up.
Kenny_Kline
Well-known member
I called wiseco and you are right they only sell in sets and the original set they sent with pistons out if the box measured .022 top ring, .032 second ring. They gave me a total seal part number to replace the 2nd ring to bring to .024 but I want to replace the top ring too to close that one up. My PTW clearance is set perfectly at .0045". I don't mind running .022 for a top ring but miscommunication between me and machine shop they gapped top ring to .024.
On second thought, can a top ring be used as a 2nd ring? If so I'd just need to order a top ring and use my original top ring as my 2nd ring. I was going to order new top and 2nd ring but if they are interchangeable, I could just order 1 ring per piston
On second thought, can a top ring be used as a 2nd ring? If so I'd just need to order a top ring and use my original top ring as my 2nd ring. I was going to order new top and 2nd ring but if they are interchangeable, I could just order 1 ring per piston
prove_it
Well-known member
From what I remember:
No, a top ring is the top ring, and the second ring is the second ring. They are not interchangeable as the bevels are different.
No, a top ring is the top ring, and the second ring is the second ring. They are not interchangeable as the bevels are different.
BogusSVO
Well-known member
The rings are made from different materials also.
IIRC the top is a 1.2mm and the 2nd is 1.5mm.
Also .002 on your ring gap will not kill the engine, or cause excessive blowby.
It will allow the ring to expand a tad more if you hit a lean condition, and just may save the piston ring lands.
Also your gaps are leaning towards CP pistons gap recommendations. That is with the old .032 2nd rings.
CP Runs a looser 2nd gap than top ring by .004 to .008.
The reason is to release the pressure between the 2 rings that can cause the top ring to flex and become unseated briefly.
IIRC the top is a 1.2mm and the 2nd is 1.5mm.
Also .002 on your ring gap will not kill the engine, or cause excessive blowby.
It will allow the ring to expand a tad more if you hit a lean condition, and just may save the piston ring lands.
Also your gaps are leaning towards CP pistons gap recommendations. That is with the old .032 2nd rings.
CP Runs a looser 2nd gap than top ring by .004 to .008.
The reason is to release the pressure between the 2 rings that can cause the top ring to flex and become unseated briefly.
Last edited:
Kenny_Kline
Well-known member
These are wiseco pistons, not CP. thanks for clarification on the top vs 2nd ring.
Wiseco gave me a total seal part number of 205017 specs: 3.77 nor ex 1.2mm thick x 144 thousandths deep $31.80
Using this ring will put me at .024 for the 2nd ring. My 1st ring is at .024 now. It came .022 out of the box but machine shop gapped them on miscommunication. So now I'm stuck looking for a top ring to bring back to .022 or I could just run .024 on 1st and 2nd ring?
I'm going for 500-600whp using a pte6266 ball bearing 35psi on pump gas hence why my p2w is at .0045 and again out of the box they were .022 top ring, .032 2nd ring but I have the part number to fix 2nd ring issue
Wiseco gave me a total seal part number of 205017 specs: 3.77 nor ex 1.2mm thick x 144 thousandths deep $31.80
Using this ring will put me at .024 for the 2nd ring. My 1st ring is at .024 now. It came .022 out of the box but machine shop gapped them on miscommunication. So now I'm stuck looking for a top ring to bring back to .022 or I could just run .024 on 1st and 2nd ring?
I'm going for 500-600whp using a pte6266 ball bearing 35psi on pump gas hence why my p2w is at .0045 and again out of the box they were .022 top ring, .032 2nd ring but I have the part number to fix 2nd ring issue
BogusSVO
Well-known member
I understand you have Wiseco pistons. I mentioned the CP for a point of referance.
There are 2 different schools of thought on ring gaps.
The old school method, Where the top ring gap is larger than the 2nd ring, Wiseco, Manley and Mahle provide ring gap factors for this method.
Then the new school of thought, where the top ring gap is smaller than the 2nd ring gap, CP provides the gap factors for this method. I found out about this method about 12 or so years ago.
Either method will work and be fine.
There are 2 different schools of thought on ring gaps.
The old school method, Where the top ring gap is larger than the 2nd ring, Wiseco, Manley and Mahle provide ring gap factors for this method.
Then the new school of thought, where the top ring gap is smaller than the 2nd ring gap, CP provides the gap factors for this method. I found out about this method about 12 or so years ago.
Either method will work and be fine.
Kenny_Kline
Well-known member
Ahhh ok gotcha.
Yeah I knew back in the day to had the bigger gap on top ring but now they changed it. Currently ring gap is at .024 top ring from wiseco, .024 2nd ring from total seal. What would you suggest I do? I'm thinking if just getting a new top ring and setting to .022 and that will give me my number if was looking for in the first place or should I run .024 .024 with what I got now?
Yeah I knew back in the day to had the bigger gap on top ring but now they changed it. Currently ring gap is at .024 top ring from wiseco, .024 2nd ring from total seal. What would you suggest I do? I'm thinking if just getting a new top ring and setting to .022 and that will give me my number if was looking for in the first place or should I run .024 .024 with what I got now?
BogusSVO
Well-known member
.024 top ring gap is not out of line.
I would have no issue running a .024/.024 gap
I really can not see a blow by issue with that spec.
It is also wide enough to keep ring ends from butting, in case of a temporary lean condition.
A .024 gap is not going to cause a ring sealing issue.
What do you think the benefits will be by having a .002 less ring gap than what you have now?
The finish grit of the cross hatch in the block is more important to ring seal and ring wear.
I would have no issue running a .024/.024 gap
I really can not see a blow by issue with that spec.
It is also wide enough to keep ring ends from butting, in case of a temporary lean condition.
A .024 gap is not going to cause a ring sealing issue.
What do you think the benefits will be by having a .002 less ring gap than what you have now?
The finish grit of the cross hatch in the block is more important to ring seal and ring wear.
Kenny_Kline
Well-known member
Block was bored with a torque plate and walls were given a platue finish?
BogusSVO
Well-known member
Good deal, sounds like they know what they are doing then.
Build on!
Build on!
