4 Bolt main Caps

-
sydcuda

sydcuda

Well-Known Member
Joined
Jan 25, 2005
Messages
395
Reaction score
30
Location
ALICE SPRINGS, AUSTRALIA
I'm putting together a 408 stroker for my cuda. Just wondering whether I should seriously consider upgrading to 4 bolt main caps as added insurance.

What have others done in their builds? Will the factory 2 bolt mains be more than adequate to handle the extra power the engine will dish out?
 
I have read that a stock mopar small block is good for up to 430 HP. I am building a 416 stroker and I am using a 4 bolt main because I am planning on 600+ HP.
 
I've read somewhere that the standard block doesn't have enough meat in it for 4 bolt mains, that the removal of metal for the bolts weakens the block. Don't know what to believe any more. You know, opinions are like a$$holes, everybody has one. I bought a stud girdle for mine. I'm sure somebody will say it's a waste of money. On a stroker, I'd at least use main studs. JMO, & you know what I just said about opinions.....vicious circle.
 
boozersdart said:
I have read that a stock mopar small block is good for up to 430 HP. I am building a 416 stroker and I am using a 4 bolt main because I am planning on 600+ HP.
Click to expand...


probably good for a little more than 430 hp.....
 
boozersdart said:
I have read that a stock mopar small block is good for up to 430 HP. I am building a 416 stroker and I am using a 4 bolt main because I am planning on 600+ HP.
Click to expand...

If you are using them on a stock block, you'll likely not like the results. The 4 bolt cap outer bolts go into an area near the base of the cylinders/webbing and cause structural issues.

A stock 340-360 block with a stud kit is good to an easy 550hp and slightly more.

If you are running 600+ hp, a stock block should not even be a cosideration IMHO. That's X and R block territory.
 
crackedback said:
If you are using them on a stock block, you'll likely not like the results. The 4 bolt cap outer bolts go into an area near the base of the cylinders/webbing and cause structural issues.

A stock 340-360 block with a stud kit is good to an easy 550hp and slightly more.

If you are running 600+ hp, a stock block should not even be a cosideration IMHO. That's X and R block territory.
Click to expand...

Good answer!!!!
 
Standard mopar small blocks are good to about 425 HP any thing more and you are driving a very expensive hand grenade. Read the book BIG-INCH mopar small blocks before you proceed with a stroker motor.
www.cartechbooks.com is a source for the book.
 
I guess all the ones I know of that are running 500-580hp for the last 5-7 years are time bombs waiting to go off. The old stock and superstock motors were bombs and none of us knew... Some have been run to death, 7000+ rpm, and freshened totaling more than 500 runs. Maybe we just have the lucky good blocks...

If anybody thinks they need a better block at the 425 level, they are wasting money. It's a falsehood. That 425 horse statement is so wrong it's not even worthy of comment. You need to remember who the author works/worked for as well.

Don't believe everything you read.
 
I just used studs...no need for a girdle, just suck your gut in :toothy10:.
 
G. G. LEVERETTE said:
Standard mopar small blocks are good to about 425 HP any thing more and you are driving a very expensive hand grenade. Read the book BIG-INCH mopar small blocks before you proceed with a stroker motor.
www.cartechbooks.com is a source for the book.
Click to expand...
Yah, i and i got some Antelope Valley beach front property i will sell you for a penny on the dollar too. I've ran plenty of stock block small blocks 425 horse and up with a heapin helping of nitrous and the only thing that has greneded was a head gasket.
 
90% of the sb strokers being built are stock 318/340/360 blocks, they are good to about 600hp with the right eqipment, start going over 600hp then i would start looking aftermarket block
 
G. G. LEVERETTE said:
Standard mopar small blocks are good to about 425 HP any thing more and you are driving a very expensive hand grenade. Read the book BIG-INCH mopar small blocks before you proceed with a stroker motor.
www.cartechbooks.com is a source for the book.
Click to expand...

Now that is pure B.S.

I used 2 bolt blocks in the Super Stocker, Super Gas and fast Bracket cars with no failures.
Insure the cap registers are tight, install a stud kit and line hone the block after installing the studs and you should be good to go.
 
Under 500hp, studded stock caps are fine. Over that, I'd add Program 2 bolt caps on all 4 and stud it. No girdles. I've got several at or over 550hp that live just fine that way. As was said... 4bolt caps will weaken the structure over all. If 600+ is really your goal, and items like solid roller cams and decent rpms regularly are on order, I'd get a better block. The prep costs will be within $1000 of a new better unit once it's ready to go.
 
well i know that we raced them on dirt at 14to1 on alcohol at 7000rpms and never lost one we had more trouble with head gaskets but double O rings took care of that.then went to the T/A blocks then the R block for 16to1.but the stock blocks im shore were pushing out some good hp #s.
 
There not like chevys, youd be suprised at what a 2 bolt main 360
block can take...
 
crackedback said:
If you are using them on a stock block, you'll likely not like the results. The 4 bolt cap outer bolts go into an area near the base of the cylinders/webbing and cause structural issues.

A stock 340-360 block with a stud kit is good to an easy 550hp and slightly more.

If you are running 600+ hp, a stock block should not even be a cosideration IMHO. That's X and R block territory.
Click to expand...

Yes I agree with the structural issues of the standard 340 block but I am using a 340 replacement Siamese block that comes with 4 bolt mains and it is rated at 650+ HP.
 
Yeah, the replacement block is designed with all the good stuff. So those 4bolt caps work brilliantly.
 
You must log in or register to reply here.
-

Back
Top