Any interest in Cranks, Rods

[sinister]

The only problem with offset grinding or cutting them down to 2.100 is that the oil hole is at a angle. if you make the journal smaller, the oil hole will get to close to the radius. This will be a problem. I to looked at cutting one down and ran into this. My solution to this is to use a Pontiac 455 rod. It is the same housing bore as a 3.8 Buick rod. It is just wider so you can get the offset right. I am working on mine as we speek and will give anyone the dimentions if they want them when I am done. Only bad part to this is you have to use a custom piston. Ross is doing mine and they are not that bad as far as price. Anyway, It should work out just great...

 

[KendallF]

Originally posted by sinister
The only problem with offset grinding or cutting them down to 2.100 is that the oil hole is at a angle. if you make the journal smaller, the oil hole will get to close to the radius. This will be a problem. I to looked at cutting one down and ran into this. My solution to this is to use a Pontiac 455 rod. It is the same housing bore as a 3.8 Buick rod. It is just wider so you can get the offset right. I am working on mine as we speek and will give anyone the dimentions if they want them when I am done. Only bad part to this is you have to use a custom piston. Ross is doing mine and they are not that bad as far as price. Anyway, It should work out just great...

The Pontiac rod sounds good but doesn't get you the stroke increase. I don't think the oil hole will be a problem when offset grinding, as the hole exits toward the outside of the throw and most of the material will be removed from the inside.

To support this, here are a couple of pictures of a 3.625 Buick Motorsports crank I had cut down to 2.100". It represents the worst case for this as it was not offset ground (stroke stayed at 3.625", more material removed on the outside of the rod throw) and the oil hole didn't move enough to be a problem.

 

[REDS HOT AIR]

Man Kendall you ruined a good crank
I got room out in the garage if your running out of space I'll store it for you

I keep reading about going to sb chevy size which I understand for offset grinding but if you have one that just needs a deep cut to straiten out the journals and your not looking to change stroke is there a down side to just going to bb chevy rods ?

Btw: back on subject .. rod crank package sounds like a good deal seems like there would be more interest in them than Im seeing in this thread

 

[Lee Thompson]

seal

Concerning knurling for the seal---I have had a couple people tell me they are running a smooth seal (Buick) on a smooth crank without leaking. I have a Moldex non knurled crank cut to size for a Buick seal (Chevy seal crank is somewhere around .020 smaller in dia. than Buick seal crank) I have an early Stage II block that takes a Buick seal. I tried 3 seals and all leaked (BTW to the best of my knowledge there is only one company that makes a neophrene Buick seal --check the # on seal) No matter what box they come in or who is sellng them (Enginetech out of Texas sells them for @4 each --the club sells the same seal @ a much higher price--they are the same seal. I checked all sources I could fine. Talked to Doug Anderson @ Grooms engine. He told me I would have to have the crank knurled as they had run into the same problem (CAN NOT RUN A SMOOTH SEAL ON A SMOOTH CRANK) One or the other has to have knurling. Check a Chevy seal and it has knurling molded into the seal. You can have knurling on both but one has to have knurling. I sent my crank back to Moldex and they put a small amount of knurling on it and told me that was all they could do as it was HARD. It did slow the leak down about 50 percent. Pulled crank and a good friend put the correct amount and @ the correct angle. Has not leaked a drop since!!!

 

[EightSecV6]

Re: seal

Originally posted by Lee Thompson
Concerning knurling for the seal---I have had a couple people tell me they are running a smooth seal (Buick) on a smooth crank without leaking. I have a Moldex non knurled crank cut to size for a Buick seal (Chevy seal crank is somewhere around .020 smaller in dia. than Buick seal crank) I have an early Stage II block that takes a Buick seal. I tried 3 seals and all leaked (BTW to the best of my knowledge there is only one company that makes a neophrene Buick seal --check the # on seal) No matter what box they come in or who is sellng them (Enginetech out of Texas sells them for @4 each --the club sells the same seal @ a much higher price--they are the same seal. I checked all sources I could fine. Talked to Doug Anderson @ Grooms engine. He told me I would have to have the crank knurled as they had run into the same problem (CAN NOT RUN A SMOOTH SEAL ON A SMOOTH CRANK) One or the other has to have knurling. Check a Chevy seal and it has knurling molded into the seal. You can have knurling on both but one has to have knurling. I sent my crank back to Moldex and they put a small amount of knurling on it and told me that was all they could do as it was HARD. It did slow the leak down about 50 percent. Pulled crank and a good friend put the correct amount and @ the correct angle. Has not leaked a drop since!!!

Lee,
I have never had that issue, that is strange how it would only be a problem in some cases. Fel Pro, Engine Tech etc are all manuf. by the same company as you stated. I can only imagine after having to pull the thing out twice (as in your case)you had to try something, I am not sure I understand exactly why, but obviously the knurling worked for you, thanks for sharing the info. All the Eagle cranks I have gotten lately have been knurled, but I have not had any leaks in either case.

 

[1ARUNEM]

FYI, I spoke with Eagle and they in fact do not make a 6" SBC H beam rod with a .912 little end. Have to get the .927 and have it bushed and hone for a .912 little end. Just a little clarification for anyone interested.

 

[Ron Tarabori]

Maybe I haven't read this clearly, but what difference does the small end make. You have to have pistons made so just have them made with the correct pin size for your rod. You cant use production pistons anyway because the pin height is going to be off.

 

[1ARUNEM]

As Bill mentioned, a little lighter..

 

[750H.P.V6]

Guys,

FWIW I would rather have a .927" pin dia. Almost every aftermarket rod that is bushed I have ever seen in a Buick application takes a SBC dia wrist pin. I don't even know what a .912 " pin dia is for. What would be the advantage to running a small pin?

Neal