New build for the Mistress

Chevy1925

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Never mind, I’m looking at it the wrong way. I thought the gray was the cap and the black was the block but it’s the other way round after scrolling up and looking at the pics above.

Interrupted cut isn’t an issue as long as you have the equipment like you were having trouble finding. Guy undersizes them on purpose so you can set the caps to match the block, keep crank center line and get you to the oil clearances you want.
 
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56taskforce

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Exactly... not just Guy they are all that way the big block Chevy caps in the second picture are Moroso caps.
The extra material also allows for adjusting for block repairs. Not everyone puts these caps on brand new blocks ie. my big block Chevy.
You would also have the same thing if you were to get a replacement factory cap.
 

1FastBrick

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For those that may not know or understand.

The New Billet Caps are made that way due to core shift. No 2 blocks are the same. One could be shifted to the right, and the next block could be shifted to the Left. The centerline can also be shifted up or down as well as side to side. This affects the way they are finish machined at the factory.

So the new caps are made undersized so they can be finished to the block.

Not all Engine Machine shops have the equipment or experience to do this. Some shops will send that out to another shop to get it done right. A lot of shops won't even touch that type of work. If it's not done correctly you essentially scrap the block.
 
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KyleC4

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So has anyone ever measured the main cap bores on a new block before? And then installed studs and re-measured the bores? Just factory caps not billet. Just to see how much distortion with the additional clamping force.

Kind of curious too just what would a machine shop charge to have to cut billet mains down and then align bore. Seems like easily a days work. Not counting all the other additional things to be done by machinist
 

56taskforce

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You shouldn't have to hone for just studs. Because I am sending it to SoCal now I will have the entire block eventhough new blueprinted. Not that I feel it is off it's just some added assurance and they know exactly what to look for should it have been a Friday afternoon block. I am also considering having the number 5 cap dowl pinned with high quality accurate pins. The SoCal cap eliminates that pin as the GM factory pin is a joke and SoCal finds it unnecessary. They do offer to pin all five caps for extreme build but I am not going that far and I am able to restrain my OCD a little.
 

56taskforce

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I am planning on spraying this motor with a two stage system and keeping tunes conservative.
 

Chevy1925

don't know sh!t about IFS
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You shouldn't have to hone for just studs. Because I am sending it to SoCal now I will have the entire block eventhough new blueprinted. Not that I feel it is off it's just some added assurance and they know exactly what to look for should it have been a Friday afternoon block. I am also considering having the number 5 cap dowl pinned with high quality accurate pins. The SoCal cap eliminates that pin as the GM factory pin is a joke and SoCal finds it unnecessary. They do offer to pin all five caps for extreme build but I am not going that far and I am able to restrain my OCD a little.

you might want to measure the bores before and after. there is a significant difference going from the tty bolt to studs and torquing to socals recommended 225ft lbs on arp studs. ive seen .001 swing up and down and when you are talking clearances measured in the .000X area with a factory clearance of .0015-.0025, that can raise an issue pretty quick. not to mention the out-of-round that occurs. im sure guys have ran that before but it doesnt help reliability. i go as far as switching bearings around in the mains and rods to get clearances as close to even across the board as possible.
 

1FastBrick

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Agreed with James! The clamping forces change with studs and While it may be minimal it can affect bearing clearance.

We do see some very minor distortion on the main caps on LS Blocks. I would imagine it's the same with any block.

Same with the Cylinder bores when using head studs. If the Block is getting head studs it gets bored and honed Using them with a deck plate as well.

The other thing you may find in the main caps, is a slight amount of taper from one side to the other of a cap. So on stock caps if you have it honed, it will correct for this issue and give you a more consistent reading across all the caps.
 

KyleC4

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.001 is a lot but that’s the info I was interested in James. I’m sure that’s not always the case but it’s good to know and why to measure.

And also agreed with 1FastBrick about LS blocks. I’ve seen the same distortion in the caps.

And why better doweling the 5th cap 56taskforce? To help with thrust? I thought Guy made his caps to accept the additional thrust bearings which I figured would help? Which I’m still curious just how much axial thrust this drivetrain produces over all different build levels
 

56taskforce

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When I inquired at SoCal about the the lack of dowl pins in the #5 billet cap the reasoning was as follows.
1. The factory GM pin was split and had insufficient strength to be effective.
2. The factory GM pin to hole clearance was too lose to be effective
With the improved stability and strength of the billet cap without pins over the factory cap with inadequate pins SoCal accepted the improvements they had made and eliminated the pins all together.
As far as my decision to have the number five cap pins back in, that is part my OCD and part from SoCal informing me that on high hp. build will add pins to all 5 caps. Beings as they add pins to all 5 caps I assume that there are more forces than thrust involved here? That I really don't know but GM found some reason behind pins on # 5 cap....
 
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Chevy1925

don't know sh!t about IFS
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GM put pins on #5 due to thrust bearing being there (crucial to have them square to the crank) and the fact you have a heavy/large rotating mass back there like the clutch fly wheel or torque converter where it will try to drive the back of the crank around forward, back, up, down, left and right.

the variance you have in the stock dowels is less than you see from studs deforming main caps but under high power with better stiffer cranks, billet fly wheels, billet converter and so on, that squareness and strength to hold square is extremely important. This is where i had explained in another post, bearings start to take the beating here when you really push it even with everything done you can do to them. ive actually see thrust bearings from mahle vary in thickness from one to the next by .0015, or have a taper, or just be too thick overall. its important to make sure both the upper and lower thrust bearing are meeting the crank surface at the same time.
 
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56taskforce

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This I understand, however the pins GM put in place as SoCal shows in their video "How to check and set Duramax end play" and the fact they don't have them on their caps from the git go shows GMs factory pins are worthless....
 

Chevy1925

don't know sh!t about IFS
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This I understand, however the pins GM put in place as SoCal shows in their video "How to check and set Duramax end play" and the fact they don't have them on their caps from the git go shows GMs factory pins are worthless....

exactly
 

KyleC4

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Dec 30, 2016
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GM put pins on #5 due to thrust bearing being there (crucial to have them square to the crank) and the fact you have a heavy/large rotating mass back there like the clutch fly wheel or torque converter where it will try to drive the back of the crank around forward, back, up, down, left and right.

the variance you have in the stock dowels is less than you see from studs deforming main caps but under high power with better stiffer cranks, billet fly wheels, billet converter and so on, that squareness and strength to hold square is extremely important. This is where i had explained in another post, bearings start to take the beating here when you really push it even with everything done you can do to them. ive actually see thrust bearings from mahle vary in thickness from one to the next by .0015, or have a taper, or just be too thick overall. its important to make sure both the upper and lower thrust bearing are meeting the crank surface at the same time.

I remember in that other post you stating the abuse you said another couple shops found of the #5 main and thrust bearing. But, I also thought you said they figured it was due to having a billet flywheel instead of the standard flex plate/flywheel combo. So what I take from this is that the billet converters are what's creating the thrust on the crank?.....And the flex plate from BD was designed to act like the stock unit and help absorb/deflect some of that thrust?....... I didn't see Guy's video showing the dowel issues and his fix. Makes sense. Every bit helps. But billet caps, girdle, dowel pins improved, and 360 thrust bearings what else can you do?! Control the right foot lol
 

56taskforce

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I remember in that other post you stating the abuse you said another couple shops found of the #5 main and thrust bearing. But, I also thought you said they figured it was due to having a billet flywheel instead of the standard flex plate/flywheel combo. So what I take from this is that the billet converters are what's creating the thrust on the crank?.....And the flex plate from BD was designed to act like the stock unit and help absorb/deflect some of that thrust?....... I didn't see Guy's video showing the dowel issues and his fix. Makes sense. Every bit helps. But billet caps, girdle, dowel pins improved, and 360 thrust bearings what else can you do?! Control the right foot lol
The video I referred dosen't mention dowl pins it simply shows installing the thrust washers putting light torque on the cap then driving the crankshaft for and aft using the crank to center the cap before final torque.
The reason that super stiff billet flex plates aren't recommended is it is almost impossible to achieve and maintain perfect alignment between the crankshaft and transmission input shaft. Not that the billet plates are bad so much more work to reap the benefits that their use is really only good for only the most extreme levels.
 

56taskforce

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The block and caps will be sent back down to SoCal for the line bore along with the heads for stg2 treatment.
While there I will have them blueprint the block and if required for the big valves overbore the cylinders. Talked with John McElravy (Fingers) on the phone had a great discussion about his pistons and a few other factors going into this build, great guy to talk to. If you are on the fence about oval bowls give John a call and discuss your concerns.
 

56taskforce

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New 2020 L5P oil Cooler and related parts do to ship out maybe tomorrow... thank you Joe Lutz (y)
 

56taskforce

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Oil cooler was delivered to Mr. Lutz damaged.3675.jpeg
For lack of a better place to pin blame and for no other reason than he works for UPS I am pointing my finger at The Bac... LOL