JE Piston ring end gap

[V6quattro]

A question for the engine bulders on here. How much piston ring and-gap should i use? Planning for 550/600 Hp. JE Piston diameter is 81.5 mm. The rings are JE to.

Any expirations on blow by and the ring-gap you have is also welcome.

Tanks,

Roy

[speeding-g60]

the rings come with a sheet to figure out a formula to determine gap.

you basically need to figure what level you expect to be at. like turbo, full blown nitrous, etc.

this next motor we are going to use the Total=Seal gapless ring set. see how that works out for us.

[V6quattro]

I take a look at the sheet. I think i'm go with the Circle-track/Drag race. Wat means it will by .017 inch (0.4318mm) for the top rings. And .018inch (0.462mm) for the 2e rings.


More people with experience at this? There is not much info on the forum about this.

Roy

[Jamo]

throw the sheet in the bin it's rubbish, speak to Aelred he specced my gap for my rings

[V6quattro]

I send Aelred the question


I did some measuring at the stock ring gap's. The top rings are all about .0125 inch. So there is enough room to play with.

Then i measured the second rings and the are around .0216 and one is .025 :corey:

So the second one's are to big!

I asked Aelred about this to. I'm not sure what cause this problem.

anyone?

Roy

[JP]

Depends on if the stock rings you measured where used or not? Subsequently wether you measured them in different bores or the same bores. Remember if used they wear out the gap varies from 18thou to 35+thou. Same applies to the bores these are not necessarily all the same. 1 thou bore difference makes a significant difference on the gaps.

As for JE rings on an 81.5 piston running the power you are seeking there is two options depending on what you need to do to achieve the desired power level.

For example if the whole setup is a cool running engine as it flows very well you can easily run top 17thou 2nd 18thou and oil ring 16thou. If however to achieve your desired power rating you run high boost and high EGT's you need to start looking at running top 18thou 2nd 20thou and oil ring 16 thou.

[V6quattro]

Depends on if the stock rings you measured where used or not? Subsequently wether you measured them in different bores or the same bores. Remember if used they wear out the gap varies from 18thou to 35+thou. Same applies to the bores these are not necessarily all the same. 1 thou bore difference makes a significant difference on the gaps.

As for JE rings on an 81.5 piston running the power you are seeking there is two options depending on what you need to do to achieve the desired power level.

For example if the whole setup is a cool running engine as it flows very well you can easily run top 17thou 2nd 18thou and oil ring 16thou. If however to achieve your desired power rating you run high boost and high EGT's you need to start looking at running top 18thou 2nd 20thou and oil ring 16 thou.

Hy,
The bores and rings are all brand new. I tried the .025 inch ring on all the cylinders and it stays the same. So it is clearly the ring. I spoke Aelred about this and Hy says Hy had this problem once. Hy ask't JE about this and they said it would by fine. . I'll send JE a mail about this this week. Lets see what the has to say about it.

[sailaz]

Then i measured the second rings and the are around .0216 and one is .025 :corey:

Had exactly the same scenario !