"Quiet" Stroker?

[69RTAlaska]

slap hot means the pistons were set-up too loose. i bet the bore is too big. some years ago some folks were using the trw clone stock replacement 400 pistons with a 4.15 crank in a 440 block. if you could find those pistons they would be quiet due to offset pins and slotted oil ring groove.

Interesting, thanks. I'm also looking into using Line2Line coating on the skirts of my current pistons to re-set the clearance perfectly. I could do the work myself, which is great when just shipping engines in and out of Alaska is ~ 2 grand.

 

[lewtot184]

Interesting, thanks. I'm also looking into using Line2Line coating on the skirts of my current pistons to re-set the clearance perfectly. I could do the work myself, which is great when just shipping engines in and out of Alaska is ~ 2 grand.

i've done the coating thing a couple of times trying to help piston clearance issues. for me it's been a short term fix, not a real solution, but hopefully your results will be longer lasting.

 

[Challenger340]

Interesting, thanks. I'm also looking into using Line2Line coating on the skirts of my current pistons to re-set the clearance perfectly. I could do the work myself, which is great when just shipping engines in and out of Alaska is ~ 2 grand.

Just stop it..... get new Pistons and start over....
because dollars to donuts your current Bores that were NOT Honed with a Torque Plate ain't properly straight/round either ?
Correcting those cylinders "straight & round" this time once a T/Plate is installed will probably require another .005" of material to work with ?

I mean **** WILL run.... you are already there ?
But after all you've been through.... do it right this time and be done with it.
So....
get the Block in somewhere with a BB Mopar T/Plate and see where they can get it to clean up at size-wise decently straight & round.... hopefully within .005" of current size..... then maybe call Diamond Pistons and see about a .005" oversize set of pistons which should be no extra charge to be made on a stocking Part # Piston

 

[4mulas]

To the OP. I find that most these big block mopar’s are mostly noisy in the valve train area of things and that it’s probably easy to confuse that for other noises…

 

[lewtot184]

disassembly, a dial bore gauge, outside mics and a little patience will tell you where your at and where you need to go.

 

[OSDart]

Have you ever walked through the pits at a drag strip and listened to the cars starting up and ideling? You'd swear they are fixing to explode!
I have two big block strokers (440/493 and a 400/470) with center pin forged pistons. Both blocks machined correctly. (Honed w/torque plate, etc,etc).
Still a bit on the noisy side.
I know a couple guys that let little noises drive them crazy. Ended up selling everything and quit racing.
I'm guilty as well. To a point.
My fix? Changed mufflers and enjoy the ride.

 

[BSB67]

This may alarm some on these boards but I now realize that for this car, quiet (relatively) takes precedence over more than stock HP. I could put the 440 crank back in to help minimize slap but I'd still rather have the cubes if I can be sure no more slap.

Alarming, no. But would have never guessed that this is where the hobby/hobbiest was going. But it is.

And based on this statement above by the OP, I don't really understand the ongoing discussion. You can build a 440 to be as quiet as the factory made them, and probably make 30 to 40 more hp than the factory did, depending on what you find to be acceptable build details.

 

[Fury Man Van]

Call the boys at 440 Source they are happy to point you in the right direction

 

[Challenger340]

Have you ever walked through the pits at a drag strip and listened to the cars starting up and ideling? You'd swear they are fixing to explode!
I have two big block strokers (440/493 and a 400/470) with center pin forged pistons. Both blocks machined correctly. (Honed w/torque plate, etc,etc).
Still a bit on the noisy side.
I know a couple guys that let little noises drive them crazy. Ended up selling everything and quit racing.
I'm guilty as well. To a point.
My fix? Changed mufflers and enjoy the ride.

Yes, but those are Drag Engines where extra Piston to Wall clearance is recommended as per the application ? = audible Piston Slap

Forged Pistons have a recommended clearance... that they will typically run at just fine at for normal driving applications, and basically quiet once warm....
with,
most Manufacturers then also specifying that an additional .001" to .003" extra clearance should be considered above the recommended clearance depending upon the application ?
for example: Drag or endurance racing, High Compression, High RPM or High Heat applications, Nitrous/Boost etc., etc..... where that 'extra' clearance and the accompanying audible Piston Slap that goes with it is expected.