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-   -   Stocker pistons; If none are on the approved list, what to do? (https://classracer.com/classforum/showthread.php?t=28750)

Jack McCarthy 10-31-2010 10:20 PM

Re: Stocker pistons; If none are on the approved list, what to do?
 
didnt have too much trouble with the witch doctor pistons, ross made them nhra approved them in about 5 weeks... went thru bruce

jack

FED 387 10-31-2010 10:34 PM

Re: Stocker pistons; If none are on the approved list, what to do?
 
Alan--I sent you a PM --Comp 387

Ed Fernandez 10-31-2010 10:37 PM

Re: Stocker pistons; If none are on the approved list, what to do?
 
Quote:

Originally Posted by ALMACK (Post 218378)
Yeah, I just got the same answer from Greg @ JE in an e-mail.
Looks like this process will take awhile....LOL

That will give you time to get a second job to pay for them and the tricky dickie rings you'll need.
You might want to try my piston co.The Fred Flintstone Forging Co. in Bed Rock Ca.They have a direct line to Danny Gs office.

Jeff Lee 10-31-2010 11:06 PM

Re: Stocker pistons; If none are on the approved list, what to do?
 
Maybe things have changed but I had great success with CP pistons turn around time, even on pistons not previously approved for Stock.
My Super Stock engine got a set of Diamond pistons in about three weeks (which do not require NHRA approval).
Along the lines of what Ed said, on some engines it can get real costly with rings if it is an odd size. My 390 AMC being one of them. I ran a 4.230" bore in Stock and I spent a lot of $$ on rings and spacers to run the 1.2mm width. It may be more cost effective to run a smaller bore if it is a more common ring size. All depends on if your after every hundredth in ET or not.
Now NHRA allows +.075 which is 4.240" for my 390. What that means to me is I can use a 4.250" ring package which will file down nicely. That gets me rings for a few hundred dollars instead of over a thousand dollars.

Dinsdale 11-01-2010 12:03 AM

Re: Stocker pistons; If none are on the approved list, what to do?
 
Quote:

Originally Posted by Jeff Lee (Post 219429)
Maybe things have changed but I had great success with CP pistons turn around time, even on pistons not previously approved for Stock.
My Super Stock engine got a set of Diamond pistons in about three weeks (which do not require NHRA approval).
Along the lines of what Ed said, on some engines it can get real costly with rings if it is an odd size. My 390 AMC being one of them. I ran a 4.230" bore in Stock and I spent a lot of $$ on rings and spacers to run the 1.2mm width. It may be more cost effective to run a smaller bore if it is a more common ring size. All depends on if your after every hundredth in ET or not.
Now NHRA allows +.075 which is 4.240" for my 390. What that means to me is I can use a 4.250" ring package which will file down nicely. That gets me rings for a few hundred dollars instead of over a thousand dollars.

Pardon my AMC stupidity, but a 4.23 bore is pretty big (thinking 427 Ford here) so what does that make the crank stroke to be 390 CI. No scientific information to prove it's any better but I've always liked the big bore/short stroke idea..

GTX JOHN 11-01-2010 12:19 AM

Re: Stocker pistons; If none are on the approved list, what to do?
 
About 3.4 inches I believe.

Jeff Lee 11-01-2010 02:26 AM

Re: Stocker pistons; If none are on the approved list, what to do?
 
Quote:

Originally Posted by Dinsdale (Post 219434)
Pardon my AMC stupidity, but a 4.23 bore is pretty big (thinking 427 Ford here) so what does that make the crank stroke to be 390 CI. No scientific information to prove it's any better but I've always liked the big bore/short stroke idea..

AMC 390 stock bore / stroke is 4.165" / 3.574" and by the time your done boring & stroking it for NHRA competition it's around 402".
The 401 AMC is 4.165" x 3.68"
And yes, 4.230" bore is standard FE 427.

Dinsdale 11-01-2010 02:55 AM

Re: Stocker pistons; If none are on the approved list, what to do?
 
Quote:

Originally Posted by Jeff Lee (Post 219440)
AMC 390 stock bore / stroke is 4.165" / 3.574" and by the time your done boring & stroking it for NHRA competition it's around 402".
The 401 AMC is 4.165" x 3.68"
And yes, 4.230" bore is standard FE 427.

Thanks Jeff.

I am familiar with FE stuff (have a couple) but am quite surprised at the big bore/short stroke of an AMC 390. Learn something every day.

Alan Roehrich 11-01-2010 07:36 AM

Re: Stocker pistons; If none are on the approved list, what to do?
 
Quote:

Originally Posted by FED 387 (Post 219423)
Alan--I sent you a PM --Comp 387

I'm good, I don't need a set for a while.

My delays had very little to do with JE, and quite a lot to do with NHRA. See the explanation above.

Ed Wright 11-01-2010 01:36 PM

Re: Stocker pistons; If none are on the approved list, what to do?
 
So, you don't have to give them a piston?

I had to donate a Scat rod to get them approved.

Got a BowTie block PN approved last year, sure was thankful I didn't have to buy an extra block! <G>


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