350 SBC Crankshaft Advice

Bob Mulry · 07-24-2019, 11:31 AM

Hi all,

I went looking through the tech specs to see if NHRA added any aftermarket replacement crankshafts for Pontiacs, which they did not.

So I went over to the tech specs for a SBC crankshaft and I found this crankshaft which is a Callies SAF113-CM listed as an NHRA legal replacement crankshaft for a 350 / 305 SBC in STOCK Eliminator.

Turned down flange, lightening holes in all rod journals, pendulum type counterweights and bull nosed…….

I don't understand the NHRA logic.

Take a look and see what you think????????????

ss3011 · 07-24-2019, 12:10 PM

No matter what the crank looks like , the one thing that remains the same is the bobweight . If the rod throws are drilled then extra weight has to be added to the counter weights . You might be able to get a similar crank approved for a Pontiac , which I hope you do !

GTX JOHN · 07-24-2019, 01:00 PM

The counterweight configuration has a very significant reduction
in windage = real horsepower gain.

I built a plexiglass side on a Mopar pan once to observe the windage.

I would kill to have a crank like that especially in my high RPM small
block combos.

That Crank is a JOKE.........I hope!

ss3011 · 07-24-2019, 05:09 PM

I agree that an improvement in windage helps HP . The crank is definitely part of that equation , baffling is part of that too . However that crank was approved , just needs to apply to all makes . Someone just took the initiative to send a crank in , and ask for approval .

Billy Nees · 07-24-2019, 06:04 PM

Quote:

Originally Posted by Bob Mulry

Hi all,

I went looking through the tech specs to see if NHRA added any aftermarket replacement crankshafts for Pontiacs, which they did not.

So I went over to the tech specs for a SBC crankshaft and I found this crankshaft which is a Callies SAF113-CM listed as an NHRA legal replacement crankshaft for a 350 / 305 SBC in STOCK Eliminator.

Turned down flange, lightening holes in all rod journals, pendulum type counterweights and bull nosed…….

I don't understand the NHRA logic.

Take a look and see what you think????????????

Bob, ya know how hard stock small-block cranks are to find! Pontiac stuff just falls out of trees!

Ed Wright · 07-24-2019, 08:14 PM

Why not send a light Pontiac Crank in for approval before complaining. Somebody went to that trouble to get that approved. As hard as it would be to find Pontiac cranks, it may be easier to get approved.

Bob Mulry · 07-25-2019, 12:14 AM

Quote:

Originally Posted by ss3011

No matter what the crank looks like , the one thing that remains the same is the bobweight . If the rod throws are drilled then extra weight has to be added to the counter weights . You might be able to get a similar crank approved for a Pontiac , which I hope you do !

You have that backwards...Take additional weight off off the counterweight to make up for the lightened journal..

Bob Mulry · 07-25-2019, 12:18 AM

Quote:

Originally Posted by Ed Wright

Why not send a light Pontiac Crank in for approval before complaining. Somebody went to that trouble to get that approved. As hard as it would be to find Pontiac cranks, it may be easier to get approved.

I don't think that Callies would be interested in duplicating that SBC in to 400ci Pontiac piece..

Maybe they could sell 20 a year vs a SBC...They get the economy of scale

Race Clean · 07-25-2019, 03:21 AM

Quote:

Originally Posted by ss3011

If the rod throws are drilled then extra weight has to be added to the counter weights .

I evidently need more education about this!

ss3011 · 07-25-2019, 08:22 AM

Quote:

Originally Posted by Race Clean

I evidently need more education about this!

Yup , Thought backwards on that one !

07-24-2019, 11:31 AM	#1
Bob Mulry VIP Member Join Date: Apr 2002 Location: Coarsegold, CA Posts: 1,016 Likes: 57 Liked 320 Times in 102 Posts	350 SBC Crankshaft Advice Hi all, I went looking through the tech specs to see if NHRA added any aftermarket replacement crankshafts for Pontiacs, which they did not. So I went over to the tech specs for a SBC crankshaft and I found this crankshaft which is a Callies SAF113-CM listed as an NHRA legal replacement crankshaft for a 350 / 305 SBC in STOCK Eliminator. Turned down flange, lightening holes in all rod journals, pendulum type counterweights and bull nosed……. I don't understand the NHRA logic. Take a look and see what you think???????????? Attached Thumbnails __________________ Bob Mulry 7516 STK A & M Motorsports

07-24-2019, 12:10 PM	#2
ss3011 Senior Member Join Date: Feb 2002 Location: Southeast Michigan Posts: 909 Likes: 70 Liked 239 Times in 114 Posts	Re: 350 SBC Crankshaft Advice No matter what the crank looks like , the one thing that remains the same is the bobweight . If the rod throws are drilled then extra weight has to be added to the counter weights . You might be able to get a similar crank approved for a Pontiac , which I hope you do ! Last edited by ss3011; 07-24-2019 at 12:12 PM. Reason: clarification

07-24-2019, 01:00 PM	#3
GTX JOHN VIP Member Join Date: Jun 2009 Location: Boulder City, Nevada 89005 Posts: 2,730 Likes: 2,790 Liked 2,469 Times in 695 Posts	Re: 350 SBC Crankshaft Advice The counterweight configuration has a very significant reduction in windage = real horsepower gain. I built a plexiglass side on a Mopar pan once to observe the windage. I would kill to have a crank like that especially in my high RPM small block combos. That Crank is a JOKE.........I hope! __________________ John Irving 741 Stock 741 Super Stock Last edited by GTX JOHN; 07-24-2019 at 01:03 PM.

07-24-2019, 05:09 PM	#4
ss3011 Senior Member Join Date: Feb 2002 Location: Southeast Michigan Posts: 909 Likes: 70 Liked 239 Times in 114 Posts	Re: 350 SBC Crankshaft Advice I agree that an improvement in windage helps HP . The crank is definitely part of that equation , baffling is part of that too . However that crank was approved , just needs to apply to all makes . Someone just took the initiative to send a crank in , and ask for approval .

07-24-2019, 08:14 PM	#6
Ed Wright Veteran Member Join Date: Mar 2005 Location: Sand Springs, OK Posts: 8,132 Likes: 896 Liked 390 Times in 170 Posts	Re: 350 SBC Crankshaft Advice Why not send a light Pontiac Crank in for approval before complaining. Somebody went to that trouble to get that approved. As hard as it would be to find Pontiac cranks, it may be easier to get approved. __________________ Ed Wright 4156 SS/JA