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Discussion Starter · #1 ·
I’m being convinced by some outside forums that a 2 bolt main block with ARP studs and every girdle on the face of the earth is stronger then a standard 4 bolt main block.

I dont mean to beat this topic to a pulp, but its an interesting one and I like hearing the input, anyone have experience with higher RPM’s and stock 2-bolt main blocks?
 

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Girdles don't do much for strength. 2 bolt will never be stronger than 4 bolt. High rpms on a stock block is possible and has been done many times however you're rolling the dice in terms of longevity.
 

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Its not really interesting honestly, regarding strength between any aftermarket 4 bolt block and any stock block. The area under the main caps on a stock block that is responsible for the rigidity and strength are very thin, this is the failure point that no girdle can rectify.
 

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Discussion Starter · #4 ·
Its not really interesting honestly, regarding strength between any aftermarket 4 bolt block and any stock block. The area under the main caps on a stock block that is responsible for the rigidity and strength are very thin, this is the failure point that no girdle can rectify.
There’s just a lot of back and forth of “well 2 bolt has more surface area” but “4 bolt holds everything together better” and Im not very experienced with what blocks hold up the longest and whether or not I should rev them up, I havent been doing stuff like that for 30+ years like some guys on here have, so if theres still somebody to this day rolling around revving their stock HO 302 to 7k since the 90’s, I want to know about it!
 

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There isnt any back and forth about surface area etc... a stock roller block is paper thin. Here is a mexican block that is a bit stronger in theory compared to a.roller block. Compare this block to this man o war 4 bolt block. Whomever you heard this from, remove them from your life, they are a horrible influence.


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There isnt any back and forth about surface area etc... a stock roller block is paper thin. Here is a mexican block that is a bit stronger in theory compared to a.roller block. Compare this block to this man o war 4 bolt block. Whomever you heard this from, remove them from your life, they are a horrible influence.


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"Mexican block stronger" is another internet myth. Its about as strong, perhaps weaker, than a stock early block. NO stronger.

My first 347 back in the early 80's proved to me that the Mexican block stronger BS is just that, BS.....
 

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I read between the lines and I think I cracked the case, just kidding. Seeing as how there are no standard 4 bolt blocks other than the old boss302 block. I believe you are alluding to someone taking a roller block and putting 4 bolt main caps on it. Because there is no human comparing a stock 302 block to an aftermarket 4 bolt block.
 

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"Mexican block stronger" is another internet myth. Its about as strong, perhaps weaker, than a stock early block. NO stronger.

My first 347 back in the early 80's proved to me that the Mexican block stronger BS is just that, BS.....
The mexican block is better in every way compared to a roller block, which is what I compared it to above. Just like an early block, you certainly gain some rigidity with blind main bolt holes compared to a roller block with open ended main.bolt holes on the roller. You also should in theory pick up some rigidity with the Mexican main cap compared to the roller cap.
 

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The mexican block is better in every way compared to a roller block, which is what I compared it to above. Just like an early block, you certainly gain some rigidity with blind main bolt holes compared to a roller block with open ended main.bolt holes on the roller. You also should in theory pick up some rigidity with the Mexican main cap compared to the roller cap.
Yes, in theory. However, the first Mexican block I used in an early 347 (cleveland crank uber machined, cunningham rods, etc) was soft as hell. It didnt last long, either.

When comparing an early block and a mexican block, they are virtually identical. The difference is in the casting material.
 

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Because there is no human comparing a stock 302 block to an aftermarket 4 bolt block.
Looks like there is a forum full of people doing just that....

I’m being convinced by some outside forums that a 2 bolt main block with ARP studs and every girdle on the face of the earth is stronger then a standard 4 bolt main block.
This is why the corral has the reputation it has. Too many experts with only keyboard experience.
 

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I still think it was referencing someone taking a stock 302 block and putting 4 bolt caps on, instead of saying a roller block with a girdle is stronger than a dart block. Lost in translation I believe.
 

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ive run a 71 service block for a lotta years and know without a doubt that a dart or world or whatever would be better... but at the time it was built, it was a stock block class... and the boss is just superior.. i did trash a 69 boss block in spectacular fashion once.... could almost remove crankshaft without taking any bolts out.... broke all the way to the cam journals on every main.
 

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Fyi... shift the discussion to ZERO BALANCE assemblies.

That's the secret in the sauce...
I'm still a 4 bolt dart block guy though.
 

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Discussion Starter · #15 ·
Fyi... shift the discussion to ZERO BALANCE assemblies.

That's the secret in the sauce...
I'm still a 4 bolt dart block guy though.
Well thats what Im saying, if I go all out, 0 internal balance, forged aluminum rotating assembly, shaft rockers and a cap girdle…
 

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You’re better off boosting a stock block and keeping the rpm under 5,800 than you are trying to spin it to the moon. RPM is not your friend on stock blocks.
 

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Well thats what Im saying, if I go all out, 0 internal balance, forged aluminum rotating assembly, shaft rockers and a cap girdle…
can you point me to this discussion that a stock 302 block with a girdle is stronger than an aftermarket 4 bolt block. Im in the mood for light reading.
 

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Discussion Starter · #20 ·
can you point me to this discussion that a stock 302 block with a girdle is stronger than an aftermarket 4 bolt block. Im in the mood for light reading.
Well they were saying that thicker ARP bolts and a cap girdle would be stronger than a 4 bolt main block. I think this was on some Chevy forum
 
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