[Jeff Kinsler]

Originally Posted by mgarblik

Here are a couple of pics of what a correct main oil feed should look like.

Yes sir.

[Jeff Kinsler]

Originally Posted by mgarblik

Thank you for that report and results from real on-track experience. This adds validity to my impressions after carefully looking those crankshafts over at PRI last year. Visually, to me the oiling circuits in the crankshaft are world's apart from the Eagle stuff and other off-shore offerings. I just hate the huge "winking eye" depressions Eagle uses to move oil from block to mains and then the rods. The Scat oiling looks similar to the way quality billet cranks carry oil. I will likely be buying a 3.25x4.25" Scat forging for my street car based on what I have seen and your experiences. Good info.

No problem just trying to help out. Your info is very valuable as well. Billet cranks are pricey now adays.

[[email protected]]

Originally Posted by Jeff Kinsler

Yea I will not post it for the reason above but anyone can send their stuff there to get it machined. I think it actually was talked about on py somewhere and people were saying that's not a good way to do it.

I bet I can guess the players in that one Lol

[hurryinhoosier62]

Originally Posted by mgarblik

Better pics of Eagle stuff.

Mike, that is pretty common even in the production side of engine remanufacturing. Like you, it doesn’t strike me as a precision machining operation.

[bad69bird]

Originally Posted by johnta1

I think that should be prerogative?



That's fine on BES thing.
It's probably well known anyway to most builders.
Goes along with Quality machine work

Haha got me on that one! Damn phone! Lol

[Dragncar]

Got mine, tested steel batch. Thanks Tom V.
Will see how it does with billet steel rods.

[Douglas Willinger]

Originally Posted by mgarblik

Here is a pic of what Eagle main oiling looks like. Essentially, a rough, giant trough, carved into the crankshaft journal. No scoop or lead into the direction of crank rotation. So large, the depression takes valuable support area away from the crankshaft. Many of the cheap Chinese shafts utilize this low cost approach of feeding oil to the bearings. If your making a few hundred HP with a V-8, probably works OK. NONE of the quality crankshaft manufacturers use this cut rate approach to oiling. Crower, Moldex, Winberg, Bryant, and now apparently Scat, choose to oil the mains properly with carefully designed scoops and directional oil flow. Not the best place to cut corners IMO.

That is what an engine shop told me in Connecticut earlier this year about the aftermarket forged steel crankshafts SCAT is OK. But avoid Eagle's because the cross drilling holes are poorly done.

As far as I know, SCAT is the only aftermarket forged steel crankshaft offering for a 3" main journal with 4" stroke for Pontiac, so that is what I purchased for my 1970 Trans Am "434" project. Am pleased to here read of people finding that SCAT makes some great alternatives to far more expensive billet cranks.

https://butlerperformance.com/i-2445...tegory:1234870

I see there is an aftermarket forged steel crankshaft with the 4" stroke for the 3.25" main journal Pontiac block. But not by SCAT, but another company "RPM"

https://butlerperformance.com/i-2445...tegory:1234872

How is the quality on that piece?

Such a size offering could be useful for a destroked 455HO or SD455.

Additionally, MOLNAR offers some options for the 3' main journal Pontiacs, with strokes of 4.25", 4.375", 4.5" and 4.65"

http://www.molnartechnologies.com/cr...m-pontiac.html

How is the quality on those compare with the comparable size SCAT 3" main journal crankshafts (4", 4.25" and 4.5" strokes)?

How do the SCAT ($799) and MOLNAR ($983) 3" main journal, 4.25' stroke offerings measure up, e.g respective weights?

And has anyone have any experience to share particularly about those more uncommon choices as the 4.375' and 4.65"

[John Langer]

Originally Posted by mgarblik

Here are a couple of pics of what a correct main oil feed should look like.

That's a start but from what I have learned, I wouldn't run my junk like that.

[Mark G]

Originally Posted by Dragncar

Got mine, tested steel batch. Thanks Tom V.
Will see how it does with billet steel rods.

I have a scat crank with tons of work done to it Oliver billet rods no problems ,,

[LiL Jack]

Looks like a brand new engine not sumn that has got that crap sprayed out of it and buzzed to 8500+

[Mark G]

Originally Posted by LiL Jack

Looks like a brand new engine not sumn that has got that crap sprayed out of it and buzzed to 8500+

it show when you have good machine work done and a engine builder to knows his stuff.. We have a shop like that here in Canada many NHRA Wally line the walls and they put my motor together in 2012 check it last year still like brand new..

[Lee]

Great information!

[mgarblik]

Originally Posted by John Langer

That's a start but from what I have learned, I wouldn't run my junk like that.

Always interested in improving our durability. If you have any pics or tips to improve our oiling further and will share, I would be interested. Currently, a crankshaft that looks like that is working for us with additional bearing and system mods, but there is always room for improvement. We run higher load than your engine, but lower RPM. When things are working correctly, we don't see over 8500 RPM. If I remember right, you routinely run 8800-9000 RPM?

[[email protected]]

Moldex version from several years ago

[Jeff Kinsler]

Pics of crank

[Dragncar]

Originally Posted by Jeff Kinsler

Pics of crank

Are you planing on running the same crank when you upgrade your heads ?

[Jeff Kinsler]

Originally Posted by Dragncar

Are you planing on running the same crank when you upgrade your heads ?

I was but just sold the rotating assembly and am getting a great deal on a crower billet.

[Scott Roberts]

Originally Posted by Jeff Kinsler

I was but just sold the rotating assembly and am getting a great deal on a crower billet.

Crower billet is a good piece... that's the crank we ran in the funnycar... 9200 rpm shifts and a lot of boost... never had an issue.
Ran .005 on the mains and .004 on the rods.. had some trick oiling mods done also...I forgot the % but it was over balanced... never hurt a bearing...not one.

[Aaron Quinton]

Thanks for sharing your results Jeff, it means a lot to help other Pontiac racers.

From what I know I think you've done a great job without center counter weights. I think you're right on edge of knocking the center mains out without your RPM but block stiffness is a big deal. I moved to a fully counter weighted crank on my junk but I'm planning to run higher rpm.

Thank you again for sharing some real information.

[Dragncar]

Originally Posted by Jeff Kinsler

I was but just sold the rotating assembly and am getting a great deal on a crower billet.

There are times when it pays off being a Pontiac racer that wins and goes rounds. Manufacturers want to be associated. Goods deals or free stuff never hurt anyone.