Gmp-55-t Cam Bearings In A Ford R/453

[CNC BLOCKS]

Would there be any benefit to machining these Ford blocks with a 2.283 cam tunnel and installing the GMP-55 babbit cam bearings as I thought maybe it would get rid of some unwanted harmonics it the valve train???

Or should I machine the first 4 journals to 2.477 and the rear journal 2.283 same as I have always done.

Just looking for Pro's and Con's

Thanks Carl

Here is some info so far
http://speedtalk.com/forum/viewtopic.php?t=12588

[Awesome Bill]

Sounds like you want to just make some holes to have larger holes! Just kidding. Any time you make that bone stiffer, you make power and lesson harmonics. Look at the LS series and what size they run 55mm for hyd roller! If GM uses it for that, just what do you think you will gain for really performance oriented engines. Yes it works. Now 60mm is common and with nascar it larger than the main bearing journal. I know, I have the Chrysler and Ford stuff on my floor now and its killer. Glad to have a short stroke engine here, the rods would be all in the way.

[CNC BLOCKS]

Actually I have a fiend that bought out Roger Penske years ago when he went from Ford to Dodge and some of their blocks had the 55MM cam bearings in them.

So far its a plus and we are set up to blue print bore the cam tunnels as most shops just go off the existing bores (not very accurate)

[Awesome Bill]

I have found with the new equipment and the ability to blue print, did not change the power output at all. So what if the cam tunnel is off .0005 or a lifter bore is out .002. Means nothing in power relationship to performance gained by making it DEAD ON. We found that the lifter angle to cam makes a good amount of power and parts living longer. As far as side to side and bore spacing, the power that you might make over leaving it alone does not prove worthy for the monies spent.
Now if this was comp elim or pro stock, yeah, do it. But with most of the racing engines produced, the cost is ridiculous and people do not want to pay for the time to correct it. And if you sell them a Dart Block and from side to side its .002 off, they don't want to hear it. And it would not hurt the block or power anyway.
If your trying to pretty up an old block, the new lifter bore bushings, 55mm cam journal, splayed cap block is still junk compared to even the SHP blocks. The GM stuff is weak and the cylinder walls walk all around just as well as the Ford and Mopar stock stuff. When starting with something as good as the Dart Block, I find it not necessary to make he holes bigger and put a sleeve in it or correct the already very close machining procedures to find power.
I do like the 55 /60 /70mm + cam tunnels for sure though. But what you gain in fixing up and old block, you loose when the cylinder walls and main saddles are moving around like a dance couple on the floor. Racing blocks are always better money spent for the power gained than any patch. Not knocking the ability to do what you do to the race blocks at all. Get it done.

[CNC BLOCKS]

I have found with the new equipment and the ability to blue print, did not change the power output at all. So what if the cam tunnel is off .0005 or a lifter bore is out .002. Means nothing in power relationship to performance gained by making it DEAD ON. We found that the lifter angle to cam makes a good amount of power and parts living longer. As far as side to side and bore spacing, the power that you might make over leaving it alone does not prove worthy for the monies spent.
Now if this was comp elim or pro stock, yeah, do it. But with most of the racing engines produced, the cost is ridiculous and people do not want to pay for the time to correct it. And if you sell them a Dart Block and from side to side its .002 off, they don't want to hear it. And it would not hurt the block or power anyway.
If your trying to pretty up an old block, the new lifter bore bushings, 55mm cam journal, splayed cap block is still junk compared to even the SHP blocks. The GM stuff is weak and the cylinder walls walk all around just as well as the Ford and Mopar stock stuff. When starting with something as good as the Dart Block, I find it not necessary to make he holes bigger and put a sleeve in it or correct the already very close machining procedures to find power.
I do like the 55 /60 /70mm + cam tunnels for sure though. But what you gain in fixing up and old block, you loose when the cylinder walls and main saddles are moving around like a dance couple on the floor. Racing blocks are always better money spent for the power gained than any patch. Not knocking the ability to do what you do to the race blocks at all. Get it done.

Do you CNC machine blocks or are you using the BHJ fixtures as its no comparison to machine a block in a CNC machine and machining off one set up as to putting together fixture to do procedure.

I can put you in touch with some machine shops we do work for that claim on there dyno that see a pretty good size improvement over what they are seeing using their fixtures.

We have found lifter bores off .025 or better and cam tunnels off .016 and running roller cams where you deal with direct center lines they must be right or seat timing events will be off.

Hopefully your not one of those guys that just throws a boring bar on the decks and bores them out.

I have all the old BHJ fixtures and they were fine back then but this 2008 and CNC machining is the wave of the future. We have been over some of our old work and back then I thought we were machining blocks pretty good till we probed a few out. HMMM

We can actually take a block and bore the cylinders to blue print in X and W locatons based of the cam and crank center lines which fixturing can not do.

We have probed out quite a few old cup blocks over the years and its amazing to see how close they are and they are done CNC machines.

What are you using to blue print bore you cam tunnels with and blue print your blocks with ??? It will be interesting to how your comparing against CNC machining or maybe you are CNC machining???

You should post this on the speedtalk site and see what happens.

I surley didn't spend 125,000.00 dollars on a CNC machine and not see a differance.

I spent some time with Dick at the PRI show who runs Darts machine shop and told him what we was finding when probing the blocks out, His answer was we ROUGH machine appox. 150 blocks a week and its up to the engine builder to make sure everything is to blue print and if they want a truely blue printed block we can also do that but it will cost some money for the time.

You should tell this to some of the Cup machine shops that CNC machining don't make a differance.

Most guys that I have these debates with don't have any CNC equipment as thats what I have seen.

I will looking for your response Carl Hinkson

[Awesome Bill]

F68 4 axis with every fixture and machine process you could think of. $147,000+. If it did not come with it, I could program it pretty quick. Worked with the machine for over 1 year and have seen no hp gains that you are talking about. Sure, we see the blueprint of the bore centers .001-.005 off, no big deal, side to side deck height .001-.002, nothing to get excited about, align bore .0005-.001 tight to high side, we still have to touch them up in the hone anyway, nothing new, lifter bores, cam tunnel etc all as close as they need to be. If Dart's stuff was that bad, I would not be using it to start with. Their stuff to date, I have found nothing I could not correct quickly and under the normal block prep. I do not use any thing else. We did get the chance to blueprint Donovons stuff and boy was I suprised. .001 from side to side and everything they done was dead on. Fred said it was nice to hear someone call and not b____!. We blue printed some other stuff and boy was I scared?

Lifter bores with older stock blocks are scary, but who uses that stuff any way. Stock blocks are out side to side but pretty close for what we have seen with what we do machine. I have never seen a cam bore out .016 let alone .005 out. Cam would not even slide in let alone turn. Send it back!

Looking at the other guy's stuff now, the 30 is out and most likely the 40 4 axis for the new years purchase. They are working on the radial clearence issue that is so easily done on the Rottler. Rottler uses the cam to crank to hold the block with air lock, very nice and easy for finding Verticle, Matt uses a solid bar going all the way threw the mains. Can't radial clearence anything and I am not pulling the block out to open for crank and rod clearence on the big engines. So he said he can work that out. Their machine is 5 times faster moving from point to point. The 4th axis on the Rottler is very very slow and sounds like a model T's transmission while rotating. The Rottler is very nice being you can do decking, probing, boring from probing or blueprint, radial clearence all in about ½ hour. I do not like the NO TOOL holder and trying to change it out. Even with the air lock cat 40, try to load the cutter head! Dirty machine, stuff flys everywhere. Matts stuff comes with a 12 or 24 tool holder, now I am looking forward to that.

What we have found once we got going is we can save a ton of time as long as the machine does its job. We have timed it. Big difference from 3 machines and 5 hours. I would consider another F68 if they fix the knee mill that moves around pretty bad! Put a Big M on the machine and then move it all the way to the left to do a resurface? WOW is all I can say. Would never consider another one unless they double the knee mill size and cut the weight of the 4th axis buy 200 lbs. Bed Mills are the only thing to use with putting that much weight to one side. Just does not work. That is why we are changing up. Found that out the hard way.

Hopefully we will make the deal at the PRI this year, hoping to is what my partner said. I would of had it this year but College with 3 children all @ one time is a ton. So I am working on that now. I only have 4 more years of that with the youngest.

What machine are you using?

[CNC BLOCKS]

F68 4 axis with every fixture and machine process you could think of. $147,000+. If it did not come with it, I could program it pretty quick. Worked with the machine for over 1 year and have seen no hp gains that you are talking about. Sure, we see the blueprint of the bore centers .001-.005 off, no big deal, side to side deck height .001-.002, nothing to get excited about, align bore .0005-.001 tight to high side, we still have to touch them up in the hone anyway, nothing new, lifter bores, cam tunnel etc all as close as they need to be. If Dart's stuff was that bad, I would not be using it to start with. Their stuff to date, I have found nothing I could not correct quickly and under the normal block prep. I do not use any thing else. We did get the chance to blueprint Donovons stuff and boy was I suprised. .001 from side to side and everything they done was dead on. Fred said it was nice to hear someone call and not b____!. We blue printed some other stuff and boy was I scared?

Lifter bores with older stock blocks are scary, but who uses that stuff any way. Stock blocks are out side to side but pretty close for what we have seen with what we do machine. I have never seen a cam bore out .016 let alone .005 out. Cam would not even slide in let alone turn. Send it back!

Looking at the other guy's stuff now, the 30 is out and most likely the 40 4 axis for the new years purchase. They are working on the radial clearence issue that is so easily done on the Rottler. Rottler uses the cam to crank to hold the block with air lock, very nice and easy for finding Verticle, Matt uses a solid bar going all the way threw the mains. Can't radial clearence anything and I am not pulling the block out to open for crank and rod clearence on the big engines. So he said he can work that out. Their machine is 5 times faster moving from point to point. The 4th axis on the Rottler is very very slow and sounds like a model T's transmission while rotating. The Rottler is very nice being you can do decking, probing, boring from probing or blueprint, radial clearence all in about ½ hour. I do not like the NO TOOL holder and trying to change it out. Even with the air lock cat 40, try to load the cutter head! Dirty machine, stuff flys everywhere. Matts stuff comes with a 12 or 24 tool holder, now I am looking forward to that.

What we have found once we got going is we can save a ton of time as long as the machine does its job. We have timed it. Big difference from 3 machines and 5 hours. I would consider another F68 if they fix the knee mill that moves around pretty bad! Put a Big M on the machine and then move it all the way to the left to do a resurface? WOW is all I can say. Would never consider another one unless they double the knee mill size and cut the weight of the 4th axis buy 200 lbs. Bed Mills are the only thing to use with putting that much weight to one side. Just does not work. That is why we are changing up. Found that out the hard way.

Hopefully we will make the deal at the PRI this year, hoping to is what my partner said. I would of had it this year but College with 3 children all @ one time is a ton. So I am working on that now. I only have 4 more years of that with the youngest.

What machine are you using?

We are using a HAAS 4-axis CNC machining center and its made to take a 3500 pound peice of iron and even a Big-M block won't phase this machine.

In the aftermarket blocks it common to find cylinder bores out up to .008 which maybe negative .008 in Y axis on one deck and positive .005 in Y axis on the other deck which is .013 total differance and to some engine builders .005 a cylinder is a big differance to them. As they want the crank center line and bore center line right on. We have seen on 010 block the bore in Y axis being off .032

We have seen lifter bores out more then .002 in Y-axis and on roller cams thats a big deal as it changes your seat timing events on opening and closing and there are 16 lifter bores your dealing with.

Cam tunnels seem to be close on the aftermarket blocks and the new Bowtie blocks seem to be with in .0005 from what we have seen lately.

We bought our machine 8 years ago from RMC and was one of the first shops to do this and now to replace our machine with all the bells and whistles is about 160,000.00 plus. And we also have a VF-3 HAAS 4-axis CNC machining center.

And because RMC does not use HAAS machines any more they told me they would not work with me any more as they are using Miltronic machines now and there customer support is not really that good. And that as not the deal when I bought a HAAS machine from them.

So if you buy a Miltronics machine and they change venders you maybe down the river like ME.

Van Norman is going to be dealing with HAAS in the near future just to give you heads up.

If you decide to buy a CNC machine with a probing cycle it will surely show machining errors in blocks that you would never find using fixturing.

Hopefully it all works out for you. Carl

[Awesome Bill]

You have the right stuff so I am told. I got into the F68 after much debate on just what I needed for what we do. When we found out all the problems because we were fairly new at it and the machine was brand new it was to late. Rottler done what they could and had too many visits because of the weight issue with the left to right machine process. We have to make another change now and have to pay again after loosing a ton in time and learning only to have to do it again. The Haas is a great machine but with the fixtures they were clueless when I purchased mine. I am still very open to anything that will work and do what they say. You are only as good as your final product. We have done this for years with equipment of old and done very well. It just is a ton easier and faster for production. I do find the loss of real skill now with the CNC stuff. But, you are now learing programmng and other things just to make with our newer toys. I can write my name in metal now that is always helpful.