4 bolt caps

fc2444 December 6th 2011, 12:43 pm

I have a dove a block and want to add the 4 bolt caps, who makes the best ones to use? Thanks

dfree383 December 6th 2011, 12:46 pm

Program has the nicest ones.

http://www.pro-gram.com/

Mark Laczo December 6th 2011, 1:38 pm

dfree383 wrote:Program has the nicest ones.
http://www.pro-gram.com/

Agreed but also the most expensive, hardest material.

From my limited experience the Milodon are also decent, mid priced. The cheapest and possibly the easiest to machine according to Paul Kane who has done this a fair amount of these conversions is the CAT brand on ebay. I have done the Milodon 4-bolt caps and they worked out nice, but I had to tell my machinist to go slowly on the align bore as the caps are harder than the block. I have a set of CAT caps (which are said to be softer than others and comparable to the block material which should mean an easier align bore) that I am going to use on the next D0VE block but have to do some sonic checking first to make sure that it is worth it on a stock block.

Hope this helps.

FWIW Mark

Paul Kane December 6th 2011, 5:50 pm

fc2444 wrote:I have a dove a block and want to add the 4 bolt caps, who makes the best ones to use? Thanks

The nicest ones of which I am aware are the Programm caps, made of 1045 billet steel. They are very nice and very expensive. Available in all shapes and sizes, too (2-bolt, splayed 4-bolt, parallel 4-bolt, # 1 cap, #5 cap, etc).

There's also the Milodon caps (made of ductile iron), and the CAT and Procomp offerings, each made with 1025 carbon steel. Even the cheapest billet splayed caps mentioned in this thread and that are lowest on the food chain are stilll more than up to the job of holding together to a point where the cast iron block would likely fail before the billet steel main caps would.

If you do use the inexpensive caps, I would recommend the Procomps over any CAT's that you may still find on the market. See my post below as to why I feel this way.

Paul

Paul Kane December 6th 2011, 5:55 pm

Mark Laczo wrote:...The cheapest and possibly the easiest to machine according to Paul Kane who has done this a fair amount of these conversions is the CAT brand on ebay. I have done the Milodon 4-bolt caps and they worked out nice, but I had to tell my machinist to go slowly on the align bore as the caps are harder than the block. I have a set of CAT caps (which are said to be softer than others and comparable to the block material which should mean an easier align bore) that I am going to use on the next D0VE block but have to do some sonic checking first to make sure that it is worth it on a stock block.

Hope this helps.

FWIW Mark

Correction: It's the CAT caps that seem to have been heat-treated and are harder than the Procomps, not the other way around. And so based on that experience I would recommed the Procomps over the CAT's.

Below is a post I made on this forum in another thread:

Paul Kane wrote:We just finished another 4 blocks: 3 D0VE-A block 4-bolt main cap conversions + 1 D9TE block 4-bolt main cap conversion with the spacers. I have always like the CAT caps because of their design, and also because I have disliked so much about ProComp in general...BUT I have to say at the time of this writing that the Procomp caps are going to be our preferred aftermarket offshore cap for the time being until CAT fixes something that we have heard about but not experienced ourselves (until now). Read on...

I have regularly suggested the CAT caps over the ProComp caps because they come with the outer bolts and also the drill pilot for drilling the outer splayed bolt holes into the block....the ProComp caps do not include these parts.

WELL, we just did the 1 D9TE block with the ProComps and the 3 D0VE-A blocks with the CATs. The Procomp capped D9TE block align-bored very easily, as expected, and it also align-honed beautifully as well. The CAT's were a nightmare by comparison. Chewed up bits no matter how light a cut we took, and there were no machine lines whatsoever after the cut (looked polished as glass). The CATs are hard as a rock. Although we don't know for sure, we suspect that they are getting heat treated overseas, which makes them way too tough to cut. Now we understand what everyone was complaining about with the CAT caps. Van talks to the owner of CAT all the time (weekly basis) and this main cap hardness matter will be brought up with him.

The Good News: the offshore main caps have an unfinshed main bore diameter of about 3.05", and so fortunately after cutting into the CATs to about a 3.15" diameter (remove .050" depth of material), the hardness of the (presumed) heat treat is gone and they being to machine normally again. So in the end, the CATs are fine....but getting to that point takes forever with a LOT of small cuts.

If you used CAT caps for your conversion and you are taking the block to a machine shop for align-bore/align-hone, be sure to enlighten the machinist of what he may observe with these caps (give him a heads-up) so that he may adjust his cutting depth, cut slower, etc., until he is past the hard surface. Otherwise you will get an earful when you pick up your block.

Hopefully, this is a temporary deal and future batches of CAT caps will eventually be non-heat treated steel.

Paul

IDT-572 December 6th 2011, 6:14 pm

I put the Cats on a D1 block with the spacers under each end like Paul did. Before my machine shop got done boring and honing , my before zero deck block turned into a positive .0075 out of the hole block.

We literally had to chew the material out of the Cat caps, couldn't make cuts light enough to make a smooth job.

I would say the description of the material is tuff very tuff.

Mark Laczo December 6th 2011, 6:30 pm

Paul Kane wrote:Correction: It's the CAT caps that seem to have been heat-treated and are harder than the Procomps, not the other way around. And so based on that experience I would recommed the Procomps over the CAT's.

Below is a post I made on this forum in another thread:

Paul Kane wrote:We just finished another 4 blocks: 3 D0VE-A block 4-bolt main cap conversions + 1 D9TE block 4-bolt main cap conversion with the spacers. I have always like the CAT caps because of their design, and also because I have disliked so much about ProComp in general...BUT I have to say at the time of this writing that the Procomp caps are going to be our preferred aftermarket offshore cap for the time being until CAT fixes something that we have heard about but not experienced ourselves (until now). Read on...

I have regularly suggested the CAT caps over the ProComp caps because they come with the outer bolts and also the drill pilot for drilling the outer splayed bolt holes into the block....the ProComp caps do not include these parts.

WELL, we just did the 1 D9TE block with the ProComps and the 3 D0VE-A blocks with the CATs. The Procomp capped D9TE block align-bored very easily, as expected, and it also align-honed beautifully as well. The CAT's were a nightmare by comparison. Chewed up bits no matter how light a cut we took, and there were no machine lines whatsoever after the cut (looked polished as glass). The CATs are hard as a rock. Although we don't know for sure, we suspect that they are getting heat treated overseas, which makes them way too tough to cut. Now we understand what everyone was complaining about with the CAT caps. Van talks to the owner of CAT all the time (weekly basis) and this main cap hardness matter will be brought up with him.

The Good News: the offshore main caps have an unfinshed main bore diameter of about 3.05", and so fortunately after cutting into the CATs to about a 3.15" diameter (remove .050" depth of material), the hardness of the (presumed) heat treat is gone and they being to machine normally again. So in the end, the CATs are fine....but getting to that point takes forever with a LOT of small cuts.

If you used CAT caps for your conversion and you are taking the block to a machine shop for align-bore/align-hone, be sure to enlighten the machinist of what he may observe with these caps (give him a heads-up) so that he may adjust his cutting depth, cut slower, etc., until he is past the hard surface. Otherwise you will get an earful when you pick up your block.

Hopefully, this is a temporary deal and future batches of CAT caps will eventually be non-heat treated steel.

Paul

Okay,

Which ones did I buy from you the older softer type or the new harder material type and is there any way to tell which is which visually ?

Mark

Paul Kane December 6th 2011, 7:25 pm

Mark Laczo wrote:Okay,

Which ones did I buy from you the older softer type or the new harder material type and is there any way to tell which is which visually ?

Mark

Mark, there seems to be some confusion: I don't know that either manufacturer (CAT & Procomp) ever offered their main caps in both "hard" and "soft." Over here, the Procomps have always been easier to align-bore, whereas the CATs have always been hard (at least on the surface/about 0.050" deep, then they get easier to cut).

The first offshore caps we used were Procomps. They went into a blown gas 521. Sometime after that me and Van both saw people on tue forums complaining about machining the CAT caps and our response to those threads was, "dude you're cutting too fast; take lighter cuts." That advice was based on the belief that all offshore stuff is the same and the CAT caps must be like the Procomps we used.

Then we did conversions with the CAT caps and were caught offgaurd by what a pain they can be compared to the Procomps. This is why I stated in my post above, "now we understand what everyone is complaining about with the CAT caps." By the way, that quote from an earlier thread on this forum is also a response to a post of yours (and which transpired long before your purchase of one of the 4-bolt cap sets that we offered for $55).

The caps you bought are CAT caps, and as far as I know they are hard-faced; we've never seen any soft ones. Just take light cuts for the first 0.050" of depth. We did three blocks in a row with the CAT caps, but yeah if I were to do that again I'd start with the Procomp caps (given a choice between the two). If you don't want to use them then just let me know, but they are like any other set of CAT main caps.

Paul

IDT-572 December 6th 2011, 9:26 pm

I just wounder if plain old hot roll would not be good enough if they were as big as the A 460 motorsport caps, and easy to machine.

Lem Evans December 6th 2011, 9:36 pm

IDT-572 wrote:I just wounder if plain old hot roll would not be good enough if they were as big as the A 460 motorsport caps, and easy to machine.

I'm not sure the kind of iron that the A460 caps are made of but, 'we' aint broke any 'yet'.

IDT-572 December 6th 2011, 9:40 pm

Lem Evans wrote:
IDT-572 wrote:I just wounder if plain old hot roll would not be good enough if they were as big as the A 460 motorsport caps, and easy to machine.

I'm not sure the kind of iron that the A460 caps are made of but, 'we' aint broke any 'yet'.

Probably ductile iron. And I doubt you will.

Lem Evans December 6th 2011, 9:47 pm

IDT-572 wrote:
Lem Evans wrote:
IDT-572 wrote:I just wounder if plain old hot roll would not be good enough if they were as big as the A 460 motorsport caps, and easy to machine.

I'm not sure the kind of iron that the A460 caps are made of but, 'we' aint broke any 'yet'.

Probably ductile iron. And I doubt you will.

So , you doubt my ability to break stuff Laughing

IDT-572 December 6th 2011, 9:51 pm

Lem Evans wrote:
IDT-572 wrote:
Lem Evans wrote:
IDT-572 wrote:I just wounder if plain old hot roll would not be good enough if they were as big as the A 460 motorsport caps, and easy to machine.

I'm not sure the kind of iron that the A460 caps are made of but, 'we' aint broke any 'yet'.

Probably ductile iron. And I doubt you will.

So , you doubt my ability to break stuff

Not the Lemonator........................ Evil or Very Mad

Lem Evans December 6th 2011, 10:25 pm

"Uncle Charlie" as he likes to be called and I had breakfast a few days ago......he has done two blocks that 4 bolts have been added. One with the Milodon caps and the other with A460 caps. Both were 4.440" bore + .080". Both blocks had cyl. walls had issues ....but....we all know that any/all blocks will go to 4.500" Rolling Eyes

IDT-572 December 6th 2011, 10:34 pm

Lem Evans wrote:"Uncle Charlie" as he likes to be called and I had breakfast a few days ago......he has done two blocks that 4 bolts have been added. One with the Milodon caps and the other with A460 caps. Both were 4.440" bore + .080". Both blocks had cyl. walls had issues ....but....we all know that any/all blocks will go to 4.500"

I hope he can sleeve them and salvage the blocks, was this found after the caps were installed?

Lem Evans December 6th 2011, 11:04 pm

IDT-572 wrote:
Lem Evans wrote:"Uncle Charlie" as he likes to be called and I had breakfast a few days ago......he has done two blocks that 4 bolts have been added. One with the Milodon caps and the other with A460 caps. Both were 4.440" bore + .080". Both blocks had cyl. walls had issues ....but....we all know that any/all blocks will go to 4.500"

I hope he can sleeve them and salvage the blocks, was this found after the caps were installed?

It was 'found' from making large HP after the caps were installed.

61coon December 6th 2011, 11:55 pm

IDT-572 wrote:I just wounder if plain old hot roll would not be good enough if they were as big as the A 460 motorsport caps, and easy to machine.

Hot rolled would probably be fine.The ones i made for you were made out of 1045 colled rolled.Easy to machine and really durable.

dfree383 December 7th 2011, 8:48 am

IDT-572 wrote:
Lem Evans wrote:"Uncle Charlie" as he likes to be called and I had breakfast a few days ago......he has done two blocks that 4 bolts have been added. One with the Milodon caps and the other with A460 caps. Both were 4.440" bore + .080". Both blocks had cyl. walls had issues ....but....we all know that any/all blocks will go to 4.500"

I hope he can sleeve them and salvage the blocks, was this found after the caps were installed?

The one with the Milodon caps was in Bobby Shrewsberry's dragster, it wasn't filled and cracked a cylinder or two, but I believe the block had alot of time on it prior to Bobby getting it, its already been sleeved and pretty sure its scrap. I'm going to install these caps on a DOVE Block I have for a 466" or a 521" motor.

The other one i believe Lem is refering to is the one from my 528 when I first put it together, Charlie got it off me and he installed the A460 Caps on it, He did a damn nice job on it, but I don't believe he's run it yet. The only time on it (Other Than Stock) was a few dozen runs and some dyno time with the factory caps and it was walking them around pretty bad and it was half filled when I put it together.

Mark Laczo December 7th 2011, 9:35 am

Paul Kane wrote:
The caps you bought are CAT caps, and as far as I know they are hard-faced; we've never seen any soft ones. Just take light cuts for the first 0.050" of depth. We did three blocks in a row with the CAT caps, but yeah if I were to do that again I'd start with the Procomp caps (given a choice between the two). If you don't want to use them then just let me know, but they are like any other set of CAT main caps.

Paul

No its all good Paul, I just wanted to be sure so that when I am getting to the machining stage I can give my guy a heads up on how hard the caps will be before hand so there are no surprizes.

Thanks Mark

Mark Laczo December 7th 2011, 9:43 am

IDT-572 wrote:I just wounder if plain old hot roll would not be good enough if they were as big as the A 460 motorsport caps, and easy to machine.

Would this be done with caps on the block or set up in some kind of a jig on a milling machine ?

Mark

61coon December 7th 2011, 7:09 pm

Mark Laczo wrote:
IDT-572 wrote:I just wounder if plain old hot roll would not be good enough if they were as big as the A 460 motorsport caps, and easy to machine.

Would this be done with caps on the block or set up in some kind of a jig on a milling machine ?

Mark

Mark,when I made the ones for Blake,I made a jig to hold the steel in place while i machined them in our machining center.I only left a little stock where the bearing surface is.(.005) This way it wouldn't be a big interrupted cut when it was all put together and machined.

61coon December 7th 2011, 7:35 pm

Sorry for the quality of this pic,but here's the last set i made for Blake.

4 bolt caps 1210101043

res0rli9 December 7th 2011, 7:48 pm

OOOOOOOH. nice Smile

Lem Evans December 7th 2011, 8:06 pm

Nice indeed .

Mark Laczo December 7th 2011, 8:25 pm

That there is some really nice craftsmanship.

Is the slot in the middle on each side, a tongue & groove type fit ? What do you charge for that kind of work ?

Mark

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