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Main Caps for 512 "B" engine

m79ded

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I am looking for recomendation Which brand main caps do you use/recommend?, I'm planning a 512 build and this looks very good. Is doing the caps enough or do I need to add girdle as well for a 700HP street build. Ive seen @andyf use those crossbolted main caps and they look great.

Thank you very much and have a great day
 
I'm interested in the responses to this question too. I've got a thick main 400 block but no caps.
Seems there are two schools of thought- aluminium caps to cushion the load, versus steel caps (or iron) with a girdle to make the bottom end as stiff and strong as possible
And please, no suggestions to buy an aftermarket block, there are no iron, and aluminum is ridiculously expensive.
 
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I'm interested in the responses to this question too. I've got a thick main 400 block but no caps.
Seems there are two schools of thought- aluminium caps to cushion the load, versus steel caps (or iron) with a girdle to make the bottom end as stiff and strong as possible
And please, no suggestions to buy an aftermarket block, there are no iron, and aluminum is ridiculously expensive.
There is a good Iron block called "The Block" by bulldog. But yes let's see what the experienced builders have used and their experiences
 
I am looking for recomendation Which brand main caps do you use/recommend?, I'm planning a 512 build and this looks very good. Is doing the caps enough or do I need to add girdle as well for a 700HP street build. Ive seen @andyf use those crossbolted main caps and they look great.

Thank you very much and have a great day

In the Charger, 500" (499) stroked 400 block, I used the aluminum BCR caps with 1/2" thick girdle designed for those caps. It works for me
http://www.bcrproducts.com/images/girdle2023.jpg

The 3 inner caps are wedge shaped, and have extra bolts that bolt to the girdle compared to being cross bolted.
The girdle is not held with the main cap bolts like the common 1/4" girdle. It uses bolts through the girdle into the wedge part of the inner 3 caps.
After align boring and honing the aluminum main caps to size, the engine assembled with the caps installed is milled so the caps and oil pan rails are all the same height. At assembly, the girdle is just sealed to the oil pan rail with a thin layer of sealant. Used the Permatex gray RTV sealer, but I may try one of the anaerobic sealers next time I have it apart.

The machine shop cost for installing aftermarket caps (either style) is not cheap, and some shops don't even have the equipment to align bore the main caps to size.
The shop I usually use (and trust) can align hone, but not bore the main caps, so I had to find another shop who could do the work.
 
good for you
do not even think of just using aligh hone
I made lots of coin fixing those butchered blocks
 
I am looking for recomendation Which brand main caps do you use/recommend?, I'm planning a 512 build and this looks very good. Is doing the caps enough or do I need to add girdle as well for a 700HP street build. Ive seen @andyf use those crossbolted main caps and they look great.

Thank you very much and have a great day


I used the cross bolt main caps, and I really like them. I will use them again on my next build.
But...
I bought mine from 440Source, not bad mouthing the company as whole, but the machining on the caps was very sub-par.
Luckily I'm a machinist and I could requalify the surfaces to make them useable.
If you go with cross bolt caps I would recommend a little higher quality ones.

20190101_211255.jpg
 
I used the cross bolt main caps, and I really like them. I will use them again on my next build.
But...
I bought mine from 440Source, not bad mouthing the company as whole, but the machining on the caps was very sub-par.
Luckily I'm a machinist and I could requalify the surfaces to make them useable.
If you go with cross bolt caps I would recommend a little higher quality ones.

View attachment 963299
Very nice, Roughly what does it cost to machine for those caps and line bore? I have the 230 block as well
 
Very nice, Roughly what does it cost to machine for those caps and line bore? I have the 230 block as well


Well I don't know how much it would cost, the shop I work at isn't an automotive type shop, more " Tool and Die ".
I fitted the caps and bored them a little undersize on the Boring Mill and paid to have it line honed.
 
700hp and 6500 it sounds like stock steel caps and a girdle should be fine. I don't think you need the cross bolted, hopefully girdle should keep the caps from walking.
 
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I am looking for recomendation Which brand main caps do you use/recommend?, I'm planning a 512 build and this looks very good. Is doing the caps enough or do I need to add girdle as well for a 700HP street build. Ive seen @andyf use those crossbolted main caps and they look great.

Thank you very much and have a great day
For a street build I'd just use the stock caps. Put ARP studs in there and have the shop hone the main line and you should be good to go.
 
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