turbo crank dispute

[hiboom]

OK guys i bought a crank from a ebay user (underoverunder) Item description says turbo Buick crank 84-87 from the pictures It wasn't clear if it was or wasn't so i asked for additional pictures which are the 4 enclosed here.It's clear to me this is not a turbo crank.when confronted about it now I'm stupid and illiterate.So to prove to ebay and pay pal that this guy wasn't honest in his item description,and I'm not the stupid one here some expert opinions would be appreciated.

 

[hiboom]

1984-87 Buick Grand National-T type OEM Crank: eBay Motors (item 150513941024 end time Nov-07-10 15:29:25 PST)
this is the actual auction

 

[gnxtc2]

Turbo crank:

What is the casting number on it?

Billy T.
gnxtc2@aol.com

 

[S2V6RACER]

It does not appear to be a turbo crank.

 

[mikestertwo]

It does not appear to be a turbo crank.

+1 :frown:

 

[jhanson1750]

Not a turbo crank and the snout doesn't look the best that I've ever seen. Looks like you made a good call based on the pics presented here. Jon Hanson

 

[hiboom]

Turbo crank:

What is the casting number on it?

Billy T.
gnxtc2@aol.com

I believe I've read on this website that the casting number can be the same on turbo cranks as NA correct me if i'm wrong .Also that's the exact picture i sent him.He told me he was a member of a GN club and I'm stupid.

 

[DavzGN]

If it was turned 30 30 as stated in the auction, would the rolled fillets still be visible? I don't know what depth the rolled fillets are, but I remember discussion on this.

David
87gn

 

[GNeric]

I have a turbo crank that I took to get just a polish on it and their machine messed up and they "went ahead and turned it" for me. .030/.030. Looks just like that. Not usable to me. They also refused to replace it.

 

[Red Regal T]

It's possible the rolled fillets would no longer be visible if it was cut .030/.030. Also, Buick V6 NA cranks have rolled fillets on the mains and not on the rod journals. The crank pictured doesn't show any rolled fillets. So therefore, in light of the .030 machining, it could be a turbo crank.

Here's a 10/10 turbo crank:

 

[mikestertwo]

I just measured 4 std. turbo cranks I have in the shop and the most shallow fillet was .015 deep on a main. Most of the fillets were between .018 and .025 deep. The deepest being on the rod journals. An .030 cut would remove the more shallow fillets. I suppose this crank could have had small fillets to begin with. Look closer at the edges of the journals. The main with the thrust bearing may have evidence of a fillet.

 

[Steve]

I have a .030/.030 crank in my shop that has no visible filets and it definately is a turbo crank. The crank came from a 60K mile one owner GN I bought a few years back with a spun rod bearing(long story). The car had never been apart or modified. I pulled the motor and had the crank turned and it had to go .030 and the cut completely removed the filets. I was a little scared of the crank so I bought a Cat forged crank to go in the motor since I was planning to build the car into a 10 second car.

 

[hiboom]

crank

Anyone have a picture of a 30 30 crank they can post.Also wouldn't the radius on the sides still be visible. Nick, Bison ,Otto .Somebody please chime in if I'm wrong then I owe this man an apology.I've put 4 of these motors together and am no expert. this crank was going in a spare short block in case the motor had problems next year before the weather got bad i could still enjoy the car without having it down the rest of the year.This is also my third turbo Buick.I bought this one 2 years ago in AZ were I met Nick.(very nice man) after I got the car was driving across country taking it home. I leaked a lot of oil on Nicks new concrete at his house. He worked on the car briefly trying to make my trip a little more comfortable. I felt really bad about that.took 20 quarts of oil to make it back to MO.

 

[87GNSteve]

The filets are what make the crank a 'turbo crank'. The NA crank with out filets and turbo crank with filets, start same the same raw casting.
The filets add strength, not the name "turbo"; so even if it was a turbo crank and they ground the filets out it is good for N/A mild service only.
Hope you get this sorted out, you got it at that price for a reason.
I sold one a few months ago for $200. + Shipping and it may have needed a 10/10 grinding as I told the guy to bring it to his machine shop.

 

[hiboom]

crank

I am allmost certain i read that it's still save to use to use a 30/30 crank on a street car into the 11's ?

 

[Slow91z]

I am allmost certain i read that it's still save to use to use a 30/30 crank on a street car into the 11's ?

Personally I would rather use a unabused NA crank then a turbo crank that had been cut on that much and probably abused.

 

[bison]

Not a 4.1/turbo crank but id use it. Id offer $100.

 

[Turbo-Archie]

If you knowingly bought a .030 crank then I think you own it..


At that point, as stated above, the "Turbo" has been cut out..


..

 

[Just a Six??]

I would still use it for 11's. The headgaskets go before most cranks do at 11's & low 12's.

 

[turbofabricator]

I have built a few engines with 30/30 cranks and have never had a failure. The main caps fail LONG before the crank does. (arguably due to crank flex).

If you are planning on running slower than a 11.0, then run it. It'll work fine IF you have your tune-up right on. If your tuneup is off, then any crank can end up bouncing off your rear axle at the top end of the track.

Remember, in the old days 400 chevy cranks were turned down .200" on the mains to fit them in a 350 block (383) They worked fine.