Billet mains

[guru]

At what point do billet mains become necessary?

Sustained high RPM use? Lots-o-power?

 

[Twin_Turbo]

rpms mostly.

 

[CNC BLOCKS]

We use 4 bolt replacement billet caps on most of our high end builds and on some of the 383's we build for the street if we can't find a 2482 cap block. Stroke is a big factor more then RPM as some of the street 383's we have built have had 500 foot pounds of torque as that is also an issue. http://www.chevelles.com/forums/showthread.php?t=106715&highlight=DYNO

We also use splayed caps on the 2 bolt main cap blocks as we can get them pretty cheap some times and engines we build over 500 get splayed caps both 2 bolt and 4 bolt blocks.

We have seen to may engines over the years in the 450 to 500 horse range and you can see where the caps have moved in the registers and the bearings show alot of wear do to the caps being unstable and splayed caps tie into the pan rail for added strenth.

Here is a pic of a block we put billet caps on and straped the rear main cap and we rate these blocks at 600 horse and they also have to pass a sonic test before we start any work on the block.

 

[guru]

Sounds like I will need billet mains.

 

[guru]

So here is something that I am wondering about.

Align boring and new mains. So if I just replace the center 3 mains with billet mains, How does align boring work on the first and last main? Doesnt it get elongated?

 

[Twin_Turbo]

They shave the caps and then move the bore down a little.

 

[guru]

That makes a lot of sense.

 

[CNC BLOCKS]

So here is something that I am wondering about.

Align boring and new mains. So if I just replace the center 3 mains with billet mains, How does align boring work on the first and last main? Doesnt it get elongated?

We line bore to size and recut the all the main caps appox. .003 and line hone from there.

 

[BRUTAL64]

We use 4 bolt replacement billet caps on most of our high end builds and on some of the 383's we build for the street if we can't find a 2482 cap block. Stroke is a big factor more then RPM as some of the street 383's we have built have had 500 foot pounds of torque as that is also an issue. http://www.chevelles.com/forums/showthread.php?t=106715&highlight=DYNO

We also use splayed caps on the 2 bolt main cap blocks as we can get them pretty cheap some times and engines we build over 500 get splayed caps both 2 bolt and 4 bolt blocks.

We have seen to may engines over the years in the 450 to 500 horse range and you can see where the caps have moved in the registers and the bearings show alot of wear do to the caps being unstable and splayed caps tie into the pan rail for added strenth.

Here is a pic of a block we put billet caps on and straped the rear main cap and we rate these blocks at 600 horse and they also have to pass a sonic test before we start any work on the block.

So someone else knows about 2482 caps. I found out about those in 78. I thought I was the only one left that knew about them. :friends:

 

[CNC BLOCKS]

We use 4 bolt replacement billet caps on most of our high end builds and on some of the 383's we build for the street if we can't find a 2482 cap block. Stroke is a big factor more then RPM as some of the street 383's we have built have had 500 foot pounds of torque as that is also an issue. http://www.chevelles.com/forums/showthread.php?t=106715&highlight=DYNO

We also use splayed caps on the 2 bolt main cap blocks as we can get them pretty cheap some times and engines we build over 500 get splayed caps both 2 bolt and 4 bolt blocks.

We have seen to may engines over the years in the 450 to 500 horse range and you can see where the caps have moved in the registers and the bearings show alot of wear do to the caps being unstable and splayed caps tie into the pan rail for added strenth.

Here is a pic of a block we put billet caps on and straped the rear main cap and we rate these blocks at 600 horse and they also have to pass a sonic test before we start any work on the block.

So someone else knows about 2482 caps. I found out about those in 78. I thought I was the only one left that knew about them. :friends:

I have treid to get all those blocks I can but only about 70% of them will pass a sonic for performance use.

 

[guru]

what is a 2482 cap?

 

[CNC BLOCKS]

what is a 2482 cap?

GM used them in their performance applications and in heavy duty truck and we have seen them in some marine applications. We use to install alot of those caps on blocks when we could buy them for 11 dollars each, But when they went to 63 each the Program billet caps were the way to go. These were the center 4 bolt caps.

Now GM stopped offering them in their catolog.

 

[BRUTAL64]

We use 4 bolt replacement billet caps on most of our high end builds and on some of the 383's we build for the street if we can't find a 2482 cap block. Stroke is a big factor more then RPM as some of the street 383's we have built have had 500 foot pounds of torque as that is also an issue. http://www.chevelles.com/forums/showthread.php?t=106715&highlight=DYNO

We also use splayed caps on the 2 bolt main cap blocks as we can get them pretty cheap some times and engines we build over 500 get splayed caps both 2 bolt and 4 bolt blocks.

We have seen to may engines over the years in the 450 to 500 horse range and you can see where the caps have moved in the registers and the bearings show alot of wear do to the caps being unstable and splayed caps tie into the pan rail for added strenth.

Here is a pic of a block we put billet caps on and straped the rear main cap and we rate these blocks at 600 horse and they also have to pass a sonic test before we start any work on the block.

So someone else knows about 2482 caps. I found out about those in 78. I thought I was the only one left that knew about them. :friends:

I have treid to get all those blocks I can but only about 70% of them will pass a sonic for performance use.

Yea, core shift is problem with those early 4 bolt blocks. I have a L82 75-76 block with the 2482 caps. It is STD bore with no taper in the bore. But I like the 400 blocks with the 4.125 bores myself. I'm using a 509 block right now in the C2. It's still is a STD bore.

 

[CNC BLOCKS]

We use 4 bolt replacement billet caps on most of our high end builds and on some of the 383's we build for the street if we can't find a 2482 cap block. Stroke is a big factor more then RPM as some of the street 383's we have built have had 500 foot pounds of torque as that is also an issue. http://www.chevelles.com/forums/showthread.php?t=106715&highlight=DYNO

We also use splayed caps on the 2 bolt main cap blocks as we can get them pretty cheap some times and engines we build over 500 get splayed caps both 2 bolt and 4 bolt blocks.

We have seen to may engines over the years in the 450 to 500 horse range and you can see where the caps have moved in the registers and the bearings show alot of wear do to the caps being unstable and splayed caps tie into the pan rail for added strenth.

Here is a pic of a block we put billet caps on and straped the rear main cap and we rate these blocks at 600 horse and they also have to pass a sonic test before we start any work on the block.

So someone else knows about 2482 caps. I found out about those in 78. I thought I was the only one left that knew about them. :friends:

I have treid to get all those blocks I can but only about 70% of them will pass a sonic for performance use.

Yea, core shift is problem with those early 4 bolt blocks. I have a L82 75-76 block with the 2482 caps. It is STD bore with no taper in the bore. But I like the 400 blocks with the 4.125 bores myself. I'm using a 509 block right now in the C2. It's still is a STD bore.

You really can't go by core shift as we have alot of those blocks that have no core but the sonic test shows thin cylinders and we have seen blocks with alot of core shift and sonic test good. So don't be fooled by core shift.

 

[BRUTAL64]

We use 4 bolt replacement billet caps on most of our high end builds and on some of the 383's we build for the street if we can't find a 2482 cap block. Stroke is a big factor more then RPM as some of the street 383's we have built have had 500 foot pounds of torque as that is also an issue. http://www.chevelles.com/forums/showthread.php?t=106715&highlight=DYNO

We also use splayed caps on the 2 bolt main cap blocks as we can get them pretty cheap some times and engines we build over 500 get splayed caps both 2 bolt and 4 bolt blocks.

We have seen to may engines over the years in the 450 to 500 horse range and you can see where the caps have moved in the registers and the bearings show alot of wear do to the caps being unstable and splayed caps tie into the pan rail for added strenth.

Here is a pic of a block we put billet caps on and straped the rear main cap and we rate these blocks at 600 horse and they also have to pass a sonic test before we start any work on the block.

So someone else knows about 2482 caps. I found out about those in 78. I thought I was the only one left that knew about them. :friends:

I have treid to get all those blocks I can but only about 70% of them will pass a sonic for performance use.

Yea, core shift is problem with those early 4 bolt blocks. I have a L82 75-76 block with the 2482 caps. It is STD bore with no taper in the bore. But I like the 400 blocks with the 4.125 bores myself. I'm using a 509 block right now in the C2. It's still is a STD bore.

You really can't go by core shift as we have alot of those blocks that have no core but the sonic test shows thin cylinders and we have seen blocks with alot of core shift and sonic test good. So don't be fooled by core shift.

Unforunately, in my CHEAP world, I have to go by core shift. So far it's worked out fairly good through the years- 78 to now. Sonic testing is the best way, by all means. I have had a few block sonic tested, but I didn't pay for it. What's Sonic testing going for now adays?

 

[CNC BLOCKS]

So someone else knows about 2482 caps. I found out about those in 78. I thought I was the only one left that knew about them. :friends:

I have treid to get all those blocks I can but only about 70% of them will pass a sonic for performance use.

Yea, core shift is problem with those early 4 bolt blocks. I have a L82 75-76 block with the 2482 caps. It is STD bore with no taper in the bore. But I like the 400 blocks with the 4.125 bores myself. I'm using a 509 block right now in the C2. It's still is a STD bore.

You really can't go by core shift as we have alot of those blocks that have no core but the sonic test shows thin cylinders and we have seen blocks with alot of core shift and sonic test good. So don't be fooled by core shift.

Unforunately, in my CHEAP world, I have to go by core shift. So far it's worked out fairly good through the years- 78 to now. Sonic testing is the best way, by all means. I have had a few block sonic tested, but I didn't pay for it. What's Sonic testing going for now adays?

If a block comes into sonic test we charge 40 dollars.

 

[BRUTAL64]

I have treid to get all those blocks I can but only about 70% of them will pass a sonic for performance use.

Yea, core shift is problem with those early 4 bolt blocks. I have a L82 75-76 block with the 2482 caps. It is STD bore with no taper in the bore. But I like the 400 blocks with the 4.125 bores myself. I'm using a 509 block right now in the C2. It's still is a STD bore.

You really can't go by core shift as we have alot of those blocks that have no core but the sonic test shows thin cylinders and we have seen blocks with alot of core shift and sonic test good. So don't be fooled by core shift.

Unforunately, in my CHEAP world, I have to go by core shift. So far it's worked out fairly good through the years- 78 to now. Sonic testing is the best way, by all means. I have had a few block sonic tested, but I didn't pay for it. What's Sonic testing going for now adays?

If a block comes into sonic test we charge 40 dollars.

Hell, only 40? Back in the day -ha ha- it was (if you could find a sonic tester) was 140 to 160.:quote:

 

[CNC BLOCKS]

Yea, core shift is problem with those early 4 bolt blocks. I have a L82 75-76 block with the 2482 caps. It is STD bore with no taper in the bore. But I like the 400 blocks with the 4.125 bores myself. I'm using a 509 block right now in the C2. It's still is a STD bore.

You really can't go by core shift as we have alot of those blocks that have no core but the sonic test shows thin cylinders and we have seen blocks with alot of core shift and sonic test good. So don't be fooled by core shift.

Unforunately, in my CHEAP world, I have to go by core shift. So far it's worked out fairly good through the years- 78 to now. Sonic testing is the best way, by all means. I have had a few block sonic tested, but I didn't pay for it. What's Sonic testing going for now adays?

If a block comes into sonic test we charge 40 dollars.

Hell, only 40? Back in the day -ha ha- it was (if you could find a sonic tester) was 140 to 160.:quote:

It only takes 10 minutes and the block does not have to be clean.