[Tom Vaught]

I have to agree that at this time a lot of Billet cranks coming out of Moldex are not cross-drilled.

We did some testing at Ford and found (like David
R.) that cross-drilling the crank did more bad than
good on high rpm engines and the oil hole did little
on the low rpm engines.

A better deal is to time (as was mentioned) the oil
feed location so that the oil has built up a "layer" of sufficient thickness so that when the crank sees maximum loading the crank and the bearing material never touch.

With a cross-drilled crank you have pulsing flow in the oil passage like a tuning pipe on an organ.
This pulsing creates high and low oil pressure conditions at the bearing surface which would like
see steady flow and pressure.

A 3/4 grooved bearing with a conventional Moldex
type oiling strategy is a better deal overall.

I believe the cranks have duplicated some of that thinking.

JMO

Tom V.

[Jeff V]

Originally Posted by Robert C.

You can order from AllPontiac.com or BOP at a future date. Delv. is early spring. I will be kicking them in the butt to get them faster. Estmated price is $1,095.00 at this time. Material is 4130 forging, and Nitrided.

( Quoted from Wade at BOP)

2. The crank will NOT be cross drilled. It will incorporate the latest technology in crank oiling, scoop oil holes and straight shot oil timing. This process pressurizes at the low pressure part of the stroke and traps the oil wedge during the high pressure part of the stroke. Cross drilling forces the oil pressure to try and overcome combustion pressure of 1000 plus psi which and translate to 10,000 psi at the bearing. This force will push the oil right back out the journal and send it to another place in the crank. Straight shot traps the oil and it has no where to go but to the rod bearing. It is the best oiling system currently available for low or high HP motors at this time.)




As you all have seen, we at AllPontiac.com and BOP are going out of our way to produce the best race parts for a pontiac that have been ever made.


Get in line soon.

If you read the post it says the crank will NOT be cross drilled...

[slowbird]

Robert C went back and edited his original post.

[J.C.you]

wade, anyone, any new info on time frame?

i could use a 3 1/4" main, 2.20" rod, 4.25" arm. someone else have a used billet piece?

[Junkyard Dog]

4.5" - is that for tow vehicle applications?

[v869tr6]

Wow this is great news. Now I will be able to build a big power turbo motor at a much more reasonable cost. A big Thanks to those involved.

[JD]

Wade or Bob C.

Will there be a possibility of a 3.75" stroke with the 4" main? A minumum order perhaps or is it just not possible?

[Robert C.]

Originally Posted by JD

Wade or Bob C.

Will there be a possibility of a 3.75" stroke with the 4" main? A minumum order perhaps or is it just not possible?

I do not think a 3.75'' is in the plan. I was told late winter early spring delv. We have samples in being work on now and all looks good.

If at anytime you'all feel the need to know just ask or call.

[Tom Vaught]

The Moldex crank I just sent to Tom McQueen had the Moldex oiling system (same as Bob C. mentioned for the forged cranks) with the oil scoops. Not Cross-drilled.

Tom V.

[WARPed]

I would also like to know about a 3.75” arm, there was talk about these in earlier plans. Has this changed?

[Tim Corcoran]

I think there will be more demand for the 3" main cranks than you might think. Many of us would like to use these cranks in 400 blocks as the 455 blocks are getting pretty rare. There are still a lot of folks who will be building motors using OEM 400 blocks. So you might consider making some 3" main cranks with 4.21, 4.0, 3.75 strokes. Lots of people are having problems with the aftermarket cast cranks, even in mild HP applications. All of us don't have the play money budget that includes after market blocks. I think that overall, the OEM cast 455 cranks are holding up much better than the after market cranks are.

Tim C

[Dragncar]

Count me in,I will have my deposit in as soon as the OK is given.But do you guys think that it is worth it to run one in a factory block since the safe horespower limits seem to be about the same for both cast cranks and OE blocks(700-750HP).Since Whittmore is taking his sweet a$$ time with my 4.25 stroke 400 block combo it has got me thinking.I mean it would not run any faster but would the reliability factor be of use since I do not plan on making more than 650 HP for the near future.

[Robert C.]

AllPontiac/BOP are planning on having 3'' and 3 1/4 main cranks. Strokes will be 4.00, 4.250 and 4.500. on the 3'' main. We do not know the stroke on the 3 1/4 crank at this time. But there will be one for that size for sure.

Yes, there are a lot of motors running the flexObend brand cranks. Some will last and some will not. You can't make power and trust this type of crank anymore.

[Wade Congdon]

The sizes are as Bob has stated and there is no plan for a 3.750 at this time. The 3.25 inch crank looks like it will be possible, but probably only in a 4.250 stroke.

[02Hawk]

Woo Hoo, all right

[68post]

Can you also machine these forgings for an Oldsmobile ? We can use the 4.25" and 4.50" strokes easily. (a 4.5" stroke and a 7.3" rod )

[Robert C.]

Originally Posted by 68post

Can you also machine these forgings for an Oldsmobile ? We can use the 4.25" and 4.50" strokes easily. (a 4.5" stroke and a 7.3" rod )

Call me on this.


804-349-0014 cell

[Half-Inch Stud]

"a 4340 non-twist forging" -wow, non-twist, somebody likes this project.

Since crank fractures happen at the journal radiussess BEFORE ever happening at the oil-drillholes, I ask aboout Radiusing: Traditional old PMD radius cut, or the new-ffangled undercut technique?

Also, what is the optimized Main Bearing set for the new crank: upper half-groove, 3/4groove, full-groove?, no groove=grooved crank, funky groovey. HIS

[68post]

Will do Bob ! Thanks !

[theoldone]

Originally Posted by Brian Baker

Define "low horsepower motor". The whole purpose of this crank is for those making in excess of 750-HP, is it not? I mean, it'll be a better bet over a cast in any application, but the cast cranks have already been proven to 750-HP reliably.

the factory cast cranks tend to develop cracks in the rod fillets after 2-3 years racing, making only 650 HP- and the factory cast cranks were actually VERY GOOD, being nodular iron- they had magnesium added to the mix to change the grain structure from flake to sphere shape

if/when these forged cranks become available, we can then throw away all the Chinese cast cranks where they belong- in the heap pile