292 rebuild questions


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By jrappl - 11 Years Ago
I'm rebuilding a '59 292 from a Edsel Ranger. It's bored 30 over.

I'm using the original cam with new bearings.
What is acceptable cam end play? How is it adjusted if it is too loose?

New 30 over pistons with Sealed Power rings (9113KX ,030)
These are not grind to fit rings (or are all rings?)

All top ring gaps are between 0.19 and 0.21
All second ring gaps are all between .014 and .015.

Shouldn't the second ring gap be a little bigger than the top to prevent piston flutter?
Do I need to grind all the second rings to something like .023?
By charliemccraney - 11 Years Ago
End play should be about .006"  If it is too loose, you can make the washer that set's that clearance a little thinner.  If it is too tight, make sure that the cam plug is not driven in too deep, that you have the right combination of spacer and cam thrust plate, and that the front bearing is not protruding from the block..

It's best to check with the ring manufacturer and do what they recommend but it sounds like you probably have them reversed (what you think is the 2nd is the 1st and what you think is the 1st is the 2nd).  Are you sure you are looking at the right rings?
By Ted - 11 Years Ago
jrappl (10/11/2014)

New 30 over pistons with Sealed Power rings (9113KX ,030)
These are not grind to fit rings (or are all rings?)

All top ring gaps are between 0.19 and 0.21
All second ring gaps are all between .014 and .015.

Shouldn't the second ring gap be a little bigger than the top to prevent piston flutter?
Do I need to grind all the second rings to something like .023?
Unless the rings are ‘file to fit’, they will come pregapped for a specific bore size.

The old school thought processes for ring end gaps called for 0.004” per inch of bore for the top ring and 0.003” per inch of bore for the second ring.  The thought processes for today’s performance applications calls for 0.0045” per inch of bore for the top ring and at least that for the second ring.  These are all minimum values and depending upon the application, even larger gaps may be called for.

The idea for an increase in second ring end gaps comes from having a larger path to remove any excess pressure that occurs between those two rings.  Being as the second ring is typically more for oil control and not controlling combustion seal, the extra gap put into the second ring is not a detriment to combustion pressures taking place above the top ring.  While the newer lighter ring packages do not exhibit much in the way of ring flutter, they are sensitive to being unseated when the pressure between the two rings gets excessive.  Having a groove machined in the piston between the two rings also helps in regards to helping to relieve any expansion taking place in this area.  That groove is referred to as an expansion groove.  Machining the pistons so that there is an increase in distance between the top and 2nd rings also helps in this regard.
By JPRappl - 11 Years Ago
I created a new account and the site is working using it - don't know what was wrong with my old account but something was...

Ted, thanks for the info.  I was reading about ring flutter but after more research I see it comes in to play in performance applications and high RPMs which I will never run.
One confusion was with the gap specs.  The top and second ring specs overlap where each ring gap could be larger or smaller than the other and still be in specs - for example .010 top and .015 bottom or .020 top and .015 bottom. Both in spec but top ring tighter in one and looser in the other.  Over thinking it I guess.

In any case I was going to try to stay close to the minimums as the rings will open up with wear.  The second rings in my set are great - all check out right at the min (.015) but the tops are all right around the mid point of the spec. Spec says .010 - .027 (or .025 depending where you find it).  Mine top rings are all very close to .019...

Installing them today!