At what HP /rpm level are billet main caps and or stud girdle needed?

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92b said:
At what level of hp/RPM are billet main caps and or stud girdles needed? How much power/RPM will stock caps with studs handle?
512 stroker 400 block
trickflow 240's
H beam scat rods
440 source 24cc dished pistons
Ohio forged crank
10.4:1
cam chioce not made yet
Mostly street driven 69 barracuda. Occasionally taken to the strip.
Thank you.
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If you do dynamic balancing all you need with this combo is main studs. With this static compression you wont be overboard as your cam size choice will be limited. Dynamic balancing is often overlooked and its really key to longevity of an engine in my view. Cam choices limitation here will also automatically limit peak rpm of this combo to safe limit.

If you plan nitrous you can think about aluminium main caps or some hardblock fill to dampen the hit, but you really dont have to go crazy here.
If you planned on bigger head and more static compression, Milodon x bolted mains with some hardblock would be my choice.
I run half filled engine in traffic all the time and I use Champion 4 row radiator with Cougar dual fans. No issue with heat at all.

Good luck!
 
Oldmanmopar said:
Milodon makes the best caps. Not only use billet but also get side bolts like Hemis and Mega blocks . Milodon side bolts are 7/16 , Other brands are 3/8's. Hard block is used when the bores are found thin during sonic testing. Big strokers should also be hard blocked before boring to prevent thin walls from distorting. Your house is only as strong as the foundation you build it on.

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This is exactly what I plan on doing in my new 500ci 230 casting short block. I will add partial fill for dampening effect as I plan to run some nitrous. Very nice!
 
RustyRatRod said:
I wouldn't even consider NOT runnin that stuff with the engine you've outlined. I'd consider it part of the assembly right off the bat. But to answer your question, I'd say a solid number is an honest 650HP, especially one that's gonna get beat on. I would also include a partial hard block fill to the bottom of the freeze plugs. Lastly, don't skimp on the cooling system.
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I was very skeptical about gridles after seeing some cheap versions untill I saw BCR setup. Also I saw some factory turbo v6 engines that have gridles, this made me think there is something to it. That said, I know many people that make over 700 without gridles in low deck 400 based setups. To each his own I guess. High quality balancing is what is most important in my view at that power level.
 
Over 30 years of running 8.60 - 10.0’s with 440 engines and I never ran one with concrete or girdle on my blocks. The only block I ever found cracks in was a 440source 500 cubic inch combo that made 275 passes running 8.60’s@155mph in my Daytona. That block had 440source steel main caps on it (I’d never do that again). I would never use a stock 440 block again at those power levels. I have a Keith Black block now and sold a mopar mega block last year.
 
pittsburghracer said:
Over 30 years of running 8.60 - 10.0’s with 440 engines and I never ran one with concrete or girdle on my blocks. The only block I ever found cracks in was a 440source 500 cubic inch combo that made 275 passes running 8.60’s@155mph in my Daytona. That block had 440source steel main caps on it (I’d never do that again). I would never use a stock 440 block again at those power levels. I have a Keith Black block now and sold a mopar mega block last year.
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Made some assumptions (you know what happens) and it looks like you got 275 passes at 800+ fwhp. That's not bad.....
 
33IMP said:
Made some assumptions (you know what happens) and it looks like you got 275 passes at 800+ fwhp. That's not bad.....
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I was very happy with that too. I never sank a lot of money into my builds so blocks were a throw away item if I got that many fast runs out of them. When I ran 10.0’s with stock redone rods and stock cranks when I tore them down for rebuilds after 3-5 years I would throw the cranks on my scrap pile. I stopped magnifluxing them because after that many passes they all came up with cracks so why waste the money checking them.
 
'68cuda416 said:
Aftermarket small blocks are sub 4 grand and are lighter and much easier to work on than a big block with headers but to each their own....I will just continue to embarrass big blocks left and right
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:D:bs_flag:I guess it helps when you pick your opponents.
 
I'll be quick to state that Cuda416 doesn't have the typical small bock, even by race standards...
 
Imploding is bad.
Just mess with them. Let’em think otherwise while you LOL
 
Thanks everyone for the replies. Lots of good info to unpack.
 
33IMP said:
One small question. Who sells an aftermarket low deck iron block? How much?
Easy to tell someone to spend money they don't have for something they can't get.....
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Indy makes aluminum low deck,
 
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92b said:
At what level of hp/RPM are billet main caps and or stud girdles needed? How much power/RPM will stock caps with studs handle?
512 stroker 400 block
trickflow 240's
H beam scat rods
440 source 24cc dished pistons
Ohio forged crank
10.4:1
cam chioce not made yet
Mostly street driven 69 barracuda. Occasionally taken to the strip.
Thank you.
Click to expand...
If you're not spinning the rpm to high, 700hp !
512 stroker kits are actually a pretty light bob weight but that's a long stroke. 400 is strong, if you get just a decent block. I run studs, line honed and good balance but only 3.915 stroke
 
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Oldmanmopar said:
Hard block is used when the bores are found thin during sonic testing. Big strokers should also be hard blocked before boring to prevent thin walls from distorting.
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Won't hard block seriously reduce the cooling system's ability to keep the bock cool? I am a very good mechanic, but I have very little experience with racing. As I understand it, hard block is a concrete like substance that you pour into the block's cooling passages, and when it hardens, it makes the cylinder walls stronger. But doesn't that take up space where coolant needs to be? I thought it was fine for race engines, but on the street????
 
harrisonm said:
Won't hard block seriously reduce the cooling system's ability to keep the bock cool? I am a very good mechanic, but I have very little experience with racing. As I understand it, hard block is a concrete like substance that you pour into the block's cooling passages, and when it hardens, it makes the cylinder walls stronger. But doesn't that take up space where coolant needs to be? I thought it was fine for race engines, but on the street????
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As the above recommendation stated, it's primarily the oil getting hot with a filled block. But yeah, reduced cooling system is part of the deal.
Even with a partial fill, an oil cooler and a big radiator is a good idea.
 
harrisonm said:
Won't hard block seriously reduce the cooling system's ability to keep the bock cool? I am a very good mechanic, but I have very little experience with racing. As I understand it, hard block is a concrete like substance that you pour into the block's cooling passages, and when it hardens, it makes the cylinder walls stronger. But doesn't that take up space where coolant needs to be? I thought it was fine for race engines, but on the street????
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Not if you don't go up too far. That's why if one still sees street time, I only recommend going to the bottom of the freeze plugs. Seen plenty like that on the street. As @33IMP mentioned, a good oil cooler will also help. There are plenty of cars running around on the street with partial fills. Hell, if you run on methanol, you can throw the radiator in the ditch. LOL
 
Lots of 650HP BB's running around on stock caps.
 
Bakerlite said:
Lots of 650HP BB's running around on stock caps.
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Sure there is. But I'm not going to recommend it and have someone run out and bust a block all to heck either.
 
92b said:
At what level of hp/RPM are billet main caps and or stud girdles needed? How much power/RPM will stock caps with studs handle?
512 stroker 400 block
trickflow 240's
H beam scat rods
440 source 24cc dished pistons
Ohio forged crank
10.4:1
cam chioce not made yet
Mostly street driven 69 barracuda. Occasionally taken to the strip.
Thank you.
Click to expand...
I do like in the fitting procees pics of the '4-bolt' caps the reisters are made a touch deeper thereby giving the caps a little more area to contain them.
 
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