[Jack Gifford]

AllPontiac- please respond to post#50. Thanks.

[Jack Gifford]

Robert C. just advised me that he'll try to get Wade to answer my post #50. Thanks.

[7T2]

Originally Posted by PONTIAC DUDE

Isn't it great to finally have all these choices to Build a Pontiac engine with...... finally.

Remember when all you had was a used 455 crank with either a 400 or 455 block. Or had to wait 6 months to a year plus for a $2600.00 billet crank.

Glad to see all these head, crank, piston, rods and block options finally reasonably priced & available for the average Racer.

Don't know of any other non production engine since the mid 70's or earlier even that has made these inroads.

It's great to be racin Pontiacs.

finally is right!
we all endured the '90's, when product innovation and inception were bleak. im personally hoping to see all those nice pontiac cars removing their corporate motors because of the new products.
jim

[Polar-Pontiac]

So let me get this straight NO 3.25 cranks for awhile.

[WARPed]

Glad I have always been a 3” main fan. Though spacers have been used in many motors with great success so what about Pontiacs? I would thing it could present some limitations to power levels but might be a fix for many large journal block owners

[Tom Vaught]

If I put a crank in a 3.25 main block with a spacer I would go all the way to a 2.75" main bearing and gain potentially a better bearing design vs the 3.25" stuff, I would use a 1/4" thick wall steel bearing spacer with a steel main cap arrangement. You can't do anything about the machining already done to the 3.25" block but you can do something about the main cap outer shell diameter and cap material.

Tom V.

[taff2]

Allpontiac/BOP, can you give me a rough idea of how much HP these forgings will take? Do you have any of the 4" forgings still in stock? Thanks.

[Robert C.]

Originally Posted by taff2

Allpontiac/BOP, can you give me a rough idea of how much HP these forgings will take? Do you have any of the 4" forgings still in stock? Thanks.

It will take 1500 hp give or take a few hundred.


And yes half are still in stock, today.

[taff2]

Thanks RobC, I think I'll have one of those,what will the shipping cost, to Oklahoma? I have a friend who works from there ,he should be able to arrange shipping to the Uk for me. Can I fax my order to you with my visa number?Thanks.

[Polar-Pontiac]

Originally Posted by Polar-Pontiac

So let me get this straight NO 3.25 cranks for awhile.

Can anyone give me a time frame.

[Wade Congdon]

PJack,

I am not for certain if the vintage Pontiac cranks used "straight shot" oiling or not. They may have had some early version of it, however I beleive Crower is credited with the modern straight shot oiling system we are implementing of these cranks.

As far as a timeframe on the 3.25 inch main cranks we just flat out don't know yet. As soon as we have what we beleive to be reliable information, you guys will be the first to know.

[Jack Gifford]

Originally Posted by Wade Congdon

... I am not for certain if the vintage Pontiac cranks used "straight shot" oiling or not.

They do, as I said before.

Originally Posted by Wade Congdon

... They may have had some early version of it, however I beleive Crower is credited with the modern straight shot oiling system we are implementing of these cranks.

Your photos show the drillings to be identical to 'vintage' cranks, so what aspect of it is "modern"?
What I'm lacking is a post-'60 Pontiac crank to look at, to observe the rod journal oiling scheme- anybody?

[johnta1]

Is 'cross-drilled' (Pontiac crank) and 'straight shot' the same is what Pontiac Jack is saying I believe.

I believe all 3.25" main cranks were cross-drilled.

[johnta1]

Looking at post #37 pics provided by Wade, the 'straight shot' is different than the 'cross-drilled' crank.

The Pontiac cross drilled crank has the oil hole on the main drilled to the opposite (180º) side of the same main. The rod journal hole is in the same spot.

Wade's pic looks like the rod journal hole goes 'straight' through to the main.

Look at the pic in HO Racing's Engine book for a pic of cross-drilled.

[Wade Congdon]

Ok, I see where some of the confusion is coming in here. First off "Straight Shot" and "Cross Drilling" are not the same animal. We stated we used modern oiling with the new cranks and Jack had questioned that saying that the oiling scheme had been around for years. Jack is correct, is has been, however the reference was made to currently readily available aftermarket cranks for Pontiac, mainly the Eagles. Most Eagles use "Cross Drilling" which has proven to be unreliable for high performance engines. Straight shot oiling on the other hand has proven to be very reliable especially in the RPM range our Pontiacs operate in. I dug out on article on this by Reher-Morrison from a May 2005 National Dragster. I hope some find it helpful.

There's big money in sequels. Just ask George Lucas; he's managed to extend the Star Wars series to nine movies. Unfortunately I don't think this second installment of my two-part column on crankshafts is going to challenge Revenge of the Sith at the box office. After all, a crankshaft is just not as exciting as a light saber. If you saved your May 27, 2005 edition of National DRAGSTER, now is the time to retrieve it from your workbench, nightstand, or race car. For those who have somehow have misplaced this issue, I'll briefly review Part I. It's my opinion that the availability of affordable aftermarket crankshafts has fueled the move toward big-inch drag racing engines. We've seen a rapid escalation in engine displacement in sportsman competition, spurred by the growing popularity of Top Sportsman, Quick 32, fast bracket racing, and similar eliminators that put a premium on horsepower and top speed. There are some significant differences among crankshafts, however. Last month I pointed out the importance of proper internal balancing and counterweight positioning in a long-stroke crank. This time my topic is oiling. I'll begin with a rather bold statement: Don't use a cross-drilled crankshaft. There are a few exceptions to this rule, but under most circumstances, a cross-drilled crank is going to cause big problems. Unfortunately cross-drilling is one of those terms that's become part of the jargon of hot rodding. People who know very little about racing engines have heard of a "cross-drilled crank," and mistakenly believe they've got to have one. In fact, cross-drilling simply refers to the position and routing of the holes that carry pressurized oil from the main bearing journals to the connecting rod bearings. In a cross-drilled crankshaft, oil feed holes are drilled completely through the main journals so the passages are open on both ends. Holes from the rod journals are then drilled at an angle to intersect the holes in the main jouranls at the centerline of the crank. This system was thought to ensure a continuous supply of oil to the rod bearings because one end of the passage drilled through the main bearing is always exposed to the pressurized oil in the upper main bearing insert. So what's wrong with this picture? The pressurized oil that enters the feed hole through the main bearing journal must overcome the centrifugal force created by the rapidly spinning crankshaft before it can reach the passage to the rod journal. If the pressure created by the oil pump is not strong enough to counteract the centrifugal force that is pulling the oil away from the rod journal feed hole, then the rod bearing is starved for lubrication. Since the pinwheel effect of the centrifugal force increases with rpm, when the rod bearing does run dry and seize, the resulting carnage is usually catastrophic. I learned my lesson about cross-drilled crankshafts the hard way. Back in the early '80s we started to turn our engines faster. We'd been running stock Chevy cranks in our 287-cubic-inch small-blocks and B/ED motors without any problems. Eventually the supply of usable cranks became exhausted, so we ordered aftermarket cranks - "California cranks" as my Texan friends called them. These cranks were much prettier than the factory forgings, and they all had trick cross-drilled main bearings. It didn't take long for those cranks to turn blue when the rod bearings burned, sometimes on the first or second dyno pull. Then we'd bolt in an old 283 crank and the engine would live forever. So what was the difference? The difference was the cross-drilling. Today most racing crankshafts have a "high-speed" oiling system, which is essentially just how Chevy drilled those stock cranks. The oil feed holes for the rod bearings intersect the main journals at or near the surface of the journals. The pressurized oil does not have to overcome centrifugal force to reach the oil feed holes for the rod bearings, so the supply of lubrication is constant even at high rpm. There have been some refinements made to the angles and positions of the oiling holes to "time" the oil supply, but the basic design hasn't changed significantly. It's easy to spot a cross-drilled crankshaft. Insert a piece of welding rod or coat hanger wire into the oil hole drilled in the main bearing. If the wire comes out the other side, the crank is cross-drilled. My advice is not to use it. It is possible to crank up the oil pressure high enough to overcome the negative effects of cross-drilling. However, excessive oil pressure creates its own set of problems, increasing parasitic losses due to windage, excessive oil on the cylinder walls, and the power that's consumed by turning a high-pressure oil pump. It's possible to manufacture a 5-inch stroke big-block crankshaft without cross-drilling the main journals. However, as the stroke becomes longer than 5 inches, the overlap between the main journals and the rod journals is reduced to the point that there is insufficient material for the oil feed holes. The crank manufacturer must then change the angle of the holes and drill them to intersect a cross-drilled passage in the main journal. When using this type of long-stroke cross-drilled crankshaft, it's absolutely essential to increase the oil pressure and install a big dry-sump tank, because this engine is going to circulate a lot of oil. It's critical for anyone assembling an engine to inspect the crankshaft carefully. The first thing we do with every crank that comes into our shop is get out a pen light and a welding rod and check the oil holes. It's not uncommon to find an oil feed hole that's blocked or not drilled quite far enough. When assembling an engine, make sure that every oil passage is open and drilled where it is supposed to be.

[johnta1]

Thanks, Wade for the info.

[Jack Gifford]

Wade- thanks for the reply.
Could anyone here with a post-1960 Pontiac crank lying around- please look to see if it's drilled for 'straight shot' oiling (see the photos in post#37)? Thanks in advance.

[Mo]

Originally Posted by pontiac jack

Wade- thanks for the reply.
Could anyone here with a post-1960 Pontiac crank lying around- please look to see if it's drilled for 'straight shot' oiling (see the photos in post#37)? Thanks in advance.

Jack, I just quickly checked a 990 crank and a 70 455 crank. Both have what I would call a "T" type oil intersection. The mains are crossdrilled and the the rod bearing oil line intersects at about the middle of the main "crossdrill" line forming a "T". HTH

[screamingchief]

Hmmm,this "crossdrilling" conversation all sounds soooo familiar...

crossdrilling thread.

Ahhh yes...

[taff2]

Allpontiac/BOP,I previously asked what will the shipping /handling cost to send one of your forged cranks to Oklahoma,can you tell me or not?