Pistons clearance

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FJ5

FJ5

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Put my pistons in.... They stick out of the block .021". Do I have them machined down or just use thicker head gasket. With the head gasket that came in my felpro kit I have .022" clearance with heads torqued.
408 stroker
RHS INDY X heads
5.9 magnum block
 
Depends on several things. What type of head is it, I'm not familiar w that head? Closed chamber w no gap at qwench area? If yes then you need thicker gasket. I think you will need at least 0.010" clearance for safety measure. I don't know gasket numbers for different thickness. You will want to run the compression calculator with your actual measurements to be sure your CR is where you want it.
 
The last stroker I built before the TT Engine had the pistons out of the hole .018 , I ended up using Felpro SD Gaskets for a Magnum and cut the top part of the gasket off. They were .054 Compressed if I remember correctly. I don't remember the part number. .036 Quench is what I ended up with. Other than that your gunna need custom gaskets. Cometic makes them. I had Indy RHS X Heads on that engine also.

EDIT..... Here are the gaskets I used. I see you are using magnum heads so here you go......

I would run these and get on down the road with it! They have a Heavy Duty Fire ring too unlike the other gaskets.

http://www.summitracing.com/parts/fel-519sd
 
Will the pistons sticking out that much cause any problems heat wise with the top ring? Just curious. Also, depending on where the measurement was taken was it the only measurement or did you rock the piston in the bore?
 
MTmopars said:
Will the pistons sticking out that much cause any problems heat wise with the top ring? Just curious. Also, depending on where the measurement was taken was it the only measurement or did you rock the piston in the bore?
Click to expand...

You need to pull out a feeler gauge and look at .021 , heat will not be an issue at all. I ran the dog piss out of my 410 stroker. I could not keep my foot off the floor. It never ever got hot. It's all in the tune. Bad tune anything can over heat even with your pistons in the hole.
 
I realize it is a small gap, I was just curious though if that amount would be enough to cause enough of a heat rise on the top ring to run a risk of it expanding more than a standard end gap factor.
 
Good question. Maybe someone will chime in and give there opinion.
 
Mad dart found them on eBay for 27.13 with free shipping. Summit was 30.95 plus 12.00 shipping.
 
but its a closed chamber head wont he be playing with fire that should really sit 005 at best shouldn't they ??
 
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