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I am getting ready to take my WA 400 Block to the machine shop for work. FIrst off, I want to put n the Eagle 455 crank with 3' journals. I WANT to use stock Pontiac rods, but the crank is set up for BBC rods, with the BBC rods being 2.20 journal diameter, and the stock Pontiac rods being 2.25. How much should I expect to pay get the crank turned the additional 0.05? Also, how much should I expect to pay for zero decking, line boring, balancing the rods, pistons, and other driveline components, hot tanking, etc. for the block? ANYONE who could tell me EVERYTHING I should expect them to do to get me rolling towards my engine build would be so greatly appreciated. I realize that different shops have different rates, in different areas of the country, but there must be a ball park figure to go by. I don't want to have one broke off in me, know what I mean? ANd, when the person taking my block realizes that I don't know squat, I'm afraid I'll REALLY get the high hard one..... So, help me be literate when I enter the shop, and know what I want and how much I should expect to pay. http://forums.performanceyears.com/g...n_confused.gif

Don Ott

Ummm.. Hate to say this, but the crank will not need to be turned down. It is already at 2.20, it needs to be upsized to the 2.25.

TIGER EFI - Electronic Fuel Injection for the Traditional Pontiac Engine. [email protected]

Dougans here in Riverside does most of my machine work. The last block I had done was about $525 or so. That included: cleaning,magnaflux, checking the deck, boring the cylinders with torque plate, install cam bearings, line hone. Not the cheapest, but they are very particular and do the job right. There are some good guys on this site that can give you better details, Dude, Ace, Spotty.

Yeah, after I thought about it, I relaized I was back asswards on the sizing.....

Are there bearings that could accomodate the difference in sizes between the rod and journal? http://forums.performanceyears.com/g...n_confused.gif

Don Ott

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by dottrz:
Are there bearings that could accomodate the difference in sizes between the rod and journal? http://forums.performanceyears.com/g...n_confused.gif<HR></BLOCKQUOTE>
Nope, that would be a .050" oversize bearing and only .040" oversize to fit a crank turned .040" under is available. You don't want that much bearing material in a performance engine anyway.

All that extra bearing material to make up for the amount ground off the crank makes for a less durable 'soft' bearing. This is why you don't really see race or performance engines built with bearings more than .020" oversize. http://forums.performanceyears.com/g.../icon_wink.gif

Just buy a stroker crank that has the 3" mains with the rod journals at the stock 2.25" Pontiac size. Ace at PPR sells them. www.pacificperformanceracing.com
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So, my only options remaining are: Use the BBC rods with the Eagle Crank; or, have a 455 crank turned down, right? How involved is turning the crank, as opposed to the cost of new rods?

Don Ott

It's not just the rods you'll be paying more for, it's also the pistons. Using a non-stock rod length with a non-stock stroke makes the requirement for the pin hole in the piston different, so you have to get custom pistons also. Butler & other Pontiac vendors sell the Eagle crank/rods/Ross piston rotating assemblies as a kit at a good price. If the price of that kit is outside your budget then you really ought to rethink the whole buildup.

You can't just turn a 455 crank down to 3" mains either, because the 3" main blocks have a narrower thrust bearing. In the good old days, people would have the thrust surface on the crank welded up to make it thicker, but welding a cast crank isn't a very good idea in a performance engine as it leads to cracking. Pontiac Dude sells a shim and bearing kit that uses an Olds thrust bearing which is the right width and diameter and it comes with a set of shims that go between the bearing and the block. I don't know anyone who's actually used this kit, but the theory sounds good. You should contact Pontiac Dude about that kit before having the machine work done on your crank though.

Would it be impossible for you to find a 455 short block? That would be your easiest and cheapest route.

If you purchase the Eagle stroker kit, it's about $2000 and that's a balanced rotating assembly. Figure another $800 or so for the machine work which includes cleaning, boring & honing, installing cam bearings, mainline hone if needed, and decking the block. Costs go up from there if you have the shop do any of the assembly for you, and I didn't include costs of head work as you didn't mention your heads or what you're doing in that area.

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'72 Formula 400 Lucerne Blue, Blue Deluxe interior - My first car!
'73 Firebird 400/4-speed Black on Black, mix & match.

I have aquired one of the 3" main "stroker" cranks. It is an early version and has a few minor problems. The snout is oversize by .002", the stroke is plus/minus .002", thrust is out to about .008-.009". The journals are within specification, it could use a tad more radius. I've also been told that these cranks are requiring some mallory metal added for balancing, but haven't got that far yet with this one. I would make contact with those selling these new "N" cranks and find out if they have tightened up on the quality control some. Once the bugs are worked out these will be a nice way to build a 455 form readily available 400 blocks. The new cranks have the stock 4.21" stroke and Pontiac rod journal sizes, no need to buy BBC rods and custom pistons.

I'd like to know at this point if any of them are in service and exactly what was needed to use the new crankshaft in terms of balancing and machining?.....Cliff

Both CAT and SCAT make a 4.210-inch stroke crank with 3-inch main journals and stock rod journal size.
A quick check of the SCAt crank suggests it's ok. The polish looked good as did the radius on the fillets, so did the chamfer on the oil holes.
Based on a pliminary check It appears the dimensions on the rod & main journals were ok. However no dimension check was made on the snout or for the stroke. It balanced to a 2210.5 bobweight with no problems.
There is apparantly one difference between the two cranks worth noting, the SCAT crank has the grooves in the area where the rope seal (or BOP Viton rear main seal) goes and the CAT crank does not have them.

We sell the rotating kits for around $1384.00 & they just require balancing which usually runs around $150.00.