.020 over wiesco ring end gap question

[3kgt2nv]

I am starting to assemble my motor and have a question about the ring end gap. I did the calculations that came with the piston rings and for a high performance car the top ring is .015 and the bottom recommendation is .018. now my question is all 4 cylinders bottom ring was at .20 with the feeler gauge. should i be worried about the extra gap or is it fine.

And my next question is will the .015 gap be to tight and cause an issue?

this is going into a 9.1 compression hx40 build that will be run in the 28-32 psi range on pump gas with meth.

 

[94_TSi]

I would make them a little less tight due to it obviously being a forced induction car, even with the meth. The .015 is iffy to me but I would definantly bring the .020 down.

 

[3kgt2nv]

I would make them a little less tight due to it obviously being a forced induction car, even with the meth. The .015 is iffy to me but I would definantly bring the .020 down.

how would i bring it down? order a different ring set? these are all uncut brand new rings that came with the pistons?

 

[white92talontsi]

Was the proper Piston to Wall clearance calculated into the machining process?

 

[94_TSi]

how would i bring it down? order a different ring set? these are all uncut brand new rings that came with the pistons?

No file the rings. You can buy a ring filer or I have clamped a file in the vice and done it by hand. Just like anything else do not take to much off you cant get the material back. File and test each ring in the cylinder it is going in til you get it where you want it.

 

[white92talontsi]

No file the rings. You can buy a ring filer or I have clamped a file in the vice and done it by hand. Just like anything else do not take to much off you cant get the material back. File and test each ring in the cylinder it is going in til you get it where you want it.

I am guessing you are not understanding what he said in his Original post. His ring gap is already larger than what is recommended so he cannot file the rings any or the gap is just going to get larger. Recommended Gap is .018 but he is already at .020 which seems to me that maybe his PTW clearance is possibly on the large side.

 

[donniekak]

Depending on the ring pack, the gap formulas usually come out to around .018", and .020". Some people insist on a tight top ring gap, this is what happens.

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[white92talontsi]

well he is talking about the bottom ring being at .020

 

[94_TSi]

I am guessing you are not understanding what he said in his Original post. His ring gap is already larger than what is recommended so he cannot file the rings any or the gap is just going to get larger. Recommended Gap is .018 but he is already at .020 which seems to me that maybe his PTW clearance is possibly on the large side.

No I didnt put it together in my head for some reason thanks for catching that. Op disregard what I said above . I personally run ring gap on the bigger side as well as a somewhat loose bore on big boost motors.

 

[donniekak]

well he is talking about the bottom ring being at .020

.020" is fine, and he needs to open the top ring up some. I've set up high boost/nitrous 4g63's at .020" and .024" with no issues. Running 30+ psi on a tight setup is asking for a cracked ring land, or opened up ring groove. You have to remember, the more heat that is put into the piston/ring, the more they expand and close up. If you start out to tight, the ends butt together, and break things.

 

[3kgt2nv]

ok so i should shoot for .20 top and .24 bottom then. Thanks this is the info that i was looking for. I knew what the spec sheet said but it made no sense that the high performance build they wanted tighter gaps than a regular street car.

thanks rep given

 

[bastard dsm]

i run about .019 top and .022 bottom, my car makes 530hp on 93oct and 30psi. pulled my catch can after 9months and is still empty...no blow-by.

 

[3kgt2nv]

thanks for the input. filed them last night to .020 and .024 though. good for confirmation that the recommended .015 and .018 is to tight.

 

[dsmmack]

Agree'd open up the ring gaps. Too tight.

at least 0.018/0.020 min sizing.