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Grinding a race crank #1708297 12/08/14 06:02 PM 12/08/14 06:02 PM
Joined: Feb 2014 Posts: 655 Huntsville, AL A Airwoofer OP mopar
Airwoofer OP mopar A Joined: Feb 2014 Posts: 655 Huntsville, AL	My builder wants me to do something about the smallish mains and rod bearings on my 3.85 Bryant crank for the 496. I hate the idea of grinding a nitride crank. What do you guys think and is it worth the risk or buy a new one? If go with the grind, where to send it and should it be re-nitrided?

Re: Grinding a race crank [Re: Airwoofer] #1708298 12/08/14 06:21 PM 12/08/14 06:21 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Whats the issue with the crank... does it need a polishing or what... if your buying bearings for it already then its a good crank IMO.... plenty of guys are turning them down to some SMALL journal sizes.. way smaller than chevy

Re: Grinding a race crank [Re: Airwoofer] #1708299 12/08/14 06:23 PM 12/08/14 06:23 PM
Joined: Aug 2003 Posts: 43,127 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,127 Bend,OR USA	Nitrided is usually .030 thick, the original Tufftriding was less than .0010 deep How small are the mains and rods? I have several sets of the older Mopar race CL77(Clevite) main bearings in .002 and .003 sizes On the rod journals what size are they? Maybe it is time to resize the rodss to get them closer to the minumum inside diameter to reduce the rod bearings clearances How much clearances do you have on both now ? BTW, what size bore are you using to get 496 C.I. out of a 3.85 stroke Mopar crank? Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: Grinding a race crank [Re: Cab_Burge] #1708300 12/08/14 06:30 PM 12/08/14 06:30 PM
Joined: Jan 2003 Posts: 19,361 Las Vegas Al_Alguire I Live Here
Al_Alguire I Live Here Joined: Jan 2003 Posts: 19,361 Las Vegas	Assume it is a 4.530" bore deal. Why does your engine builder want a different main and rod size? As stated plenty of cars out there running Honda or smaller rod journals, on the mains would depend on what the application was for me. But don't see how you will make them bigger??? IMO buy a new crank if he thinks wither are an issue. Sell what you have to someone who is looking to go with smaller journals. "I am not ashamed to confess I am ignorant of what I do not know." "It's never wrong to do the right thing"

Re: Grinding a race crank [Re: MR_P_BODY] #1708301 12/08/14 06:46 PM 12/08/14 06:46 PM
Joined: Feb 2014 Posts: 655 Huntsville, AL A Airwoofer OP mopar
Airwoofer OP mopar A Joined: Feb 2014 Posts: 655 Huntsville, AL	I don't have the numbers but he says it is too small. The motor had good oil pressure before it was taken apart so I have to wonder what's so bad about too much clearance? This crank has been through that bad shop in Memphis and the journals have been polished too much I think. Problem is I am in the process of having pistons made for it that will also match the wore out 4.538 bore. The rings are expensive. With 47cc chamber heads I need 38cc dish and 0.060 in the hole to get 10-1 which is kinda high but usable with the side slinger blower. Could get a new crank but finding one with that same stroke may be tough. Any more stroke and it will take even more dish or further down in the hole. That would push the comp height. I feel like I am trying to make a silk purse outta a pigs ear here.

Re: Grinding a race crank [Re: Airwoofer] #1708302 12/08/14 06:57 PM 12/08/14 06:57 PM
A Anonymous Unregistered
Anonymous Unregistered A	Nitride is for wear protection--who cares? Grind it using professional crank shop and keep rolling--if it was in a dirt car that was going to eat abbrasive all season yea nitride is a good thing but your engine will never know you cut through that crust--it won't care at all!!!! It will LOVE the fact that you now have round/true/untapered journals and an even fatter radius. I have cut about 65 440 cranks down to 383 mains and raced the SNOT out of them--Never ever an issue----Grind it--race it--Forget it! It will not wear unless it had dirt in there so .......

Re: Grinding a race crank [Re: Al_Alguire] #1708303 12/08/14 07:00 PM 12/08/14 07:00 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Quote: Assume it is a 4.530" bore deal. Why does your engine builder want a different main and rod size? As stated plenty of cars out there running Honda or smaller rod journals, on the mains would depend on what the application was for me. But don't see how you will make them bigger??? IMO buy a new crank if he thinks wither are an issue. Sell what you have to someone who is looking to go with smaller journals. I had a billet crank welded up, ground and nitrided.... sorry I had it welded up.. only needed to be turned .020.... but it was a new crank

Re: Grinding a race crank [Re: Airwoofer] #1708304 12/08/14 07:00 PM 12/08/14 07:00 PM
A Anonymous Unregistered
Anonymous Unregistered A	Quote: I don't have the numbers but he says it is too small. The motor had good oil pressure before it was taken apart so I have to wonder what's so bad about too much clearance? This crank has been through that bad shop in Memphis and the journals have been polished too much I think. Problem is I am in the process of having pistons made for it that will also match the wore out 4.538 bore. The rings are expensive. With 47cc chamber heads I need 38cc dish and 0.060 in the hole to get 10-1 which is kinda high but usable with the side slinger blower. Could get a new crank but finding one with that same stroke may be tough. Any more stroke and it will take even more dish or further down in the hole. That would push the comp height. I feel like I am trying to make a silk purse outta a pigs ear here. Lots of Pigs Ear engines win races every season--in fact they are the most fun--winning with less than Perfect engines is the Normal--The perfect anal guys never sleep at night because they worry too much and can't win--Us Dumb racers put our " junk" together and never think of it again and can Concentrate on winning races

Re: Grinding a race crank [Re: ] #1708305 12/08/14 08:57 PM 12/08/14 08:57 PM
Joined: Mar 2006 Posts: 9,827 MI, usa dvw master
dvw master Joined: Mar 2006 Posts: 9,827 MI, usa	For what it's worth this is my 2 cents. A wise man said if you have too much bearing clearance you alone will know. If you don't have enough , everyone will know. As long as bearings are available or clearance isn't out of this world, it should work fine.Same with rings. 4.5035" file fit in your bore may work a blower motor wants a big gap anyway. I doubt it will know the difference. The biggest issue here is you are questioning your engine builder. You both need to be on the same page. If you don't trust what he's telling you asking on line is a crap shoot. Lots of knowledge, lots of misinformation, just need to know how to sift through it. Doug

Re: Grinding a race crank [Re: ] #1708306 12/09/14 12:31 PM 12/09/14 12:31 PM
Joined: Jan 2003 Posts: 1,142 Central New York slippery440 Crybaby440
slippery440 Crybaby440 Joined: Jan 2003 Posts: 1,142 Central New York	Lots of Pigs Ear engines win races every season--in fact they are the most fun--winning with less than Perfect engines is the Normal--The perfect anal guys never sleep at night because they worry too much and can't win--Us Dumb racers put our " junk" together and never think of it again and can Concentrate on winning races I LIKE THAT !!!! So dam true If the MODS did their job I would not be hitting the notify MOD button. LOL

Re: Grinding a race crank [Re: dvw] #1708307 12/09/14 12:50 PM 12/09/14 12:50 PM
Joined: Feb 2014 Posts: 655 Huntsville, AL A Airwoofer OP mopar
Airwoofer OP mopar A Joined: Feb 2014 Posts: 655 Huntsville, AL	Quote: For what it's worth this is my 2 cents. A wise man said if you have too much bearing clearance you alone will know. If you don't have enough , everyone will know. As long as bearings are available or clearance isn't out of this world, it should work fine.Same with rings. 4.5035" file fit in your bore may work a blower motor wants a big gap anyway. I doubt it will know the difference. The biggest issue here is you are questioning your engine builder. You both need to be on the same page. If you don't trust what he's telling you asking on line is a crap shoot. Lots of knowledge, lots of misinformation, just need to know how to sift through it. Doug I do trust this guy and we have a great working relationship, which is why my junk is in his shop. He says the crank needs turning which puts me in a spot. He is not a big machine shop. I do not know of a shop in this area (N Alabama) that I could trust to do the job right. LOL, he has mentioned Ohio Crankshaft but with the upcoming football game between OSU and Bama maybe not the best idea to send it up there . The cutting off of the nitride is also a concern to me but maybe that is false worry. I will find out what the actual numbers are and look at the old bearing shells. The darn thing may need straightening, I know a bunch of the balance holes are gonna need to be filled as I go from alum BME rods to steel Callies (and longer also) and there are a bunch of them holes. Total Seal is suggesting 4.535 gapless top and second rings, 0.043 wide.

Re: Grinding a race crank [Re: Airwoofer] #1708308 12/09/14 01:08 PM 12/09/14 01:08 PM
Joined: Dec 2013 Posts: 403 Romulus, MI GTS340 mopar
GTS340 mopar Joined: Dec 2013 Posts: 403 Romulus, MI	Does Huntsville engines not grind cranks? There are a few trustworthy places in Detroit.

Re: Grinding a race crank [Re: GTS340] #1708309 12/09/14 01:18 PM 12/09/14 01:18 PM
Joined: Jun 2004 Posts: 2,360 Mobile Alabama S SB412DUSTER top fuel
SB412DUSTER top fuel S Joined: Jun 2004 Posts: 2,360 Mobile Alabama	I've sent 3 cranks to Lunati crankshaft repair and got excellent service. 1 was a Lunati and the other 2 were Callies, They can re-nitrate to if you want. They are in north Mississippi

Re: Grinding a race crank [Re: SB412DUSTER] #1708310 12/09/14 01:33 PM 12/09/14 01:33 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Quote: I've sent 3 cranks to Lunati crankshaft repair and got excellent service. 1 was a Lunati and the other 2 were Callies, They can re-nitrate to if you want. They are in north Mississippi I had the one crank repaired and re-nitrated... getting the nitrating isnt cheap but I like it.. EDIT I had that work done local at Crankshaft Specialist.. they did a NICE job... the guy that did the work offered to buy that crank... it was one of my 3.79 cranks Last edited by MR_P_BODY; 12/09/14 01:36 PM.

Re: Grinding a race crank [Re: Airwoofer] #1708311 12/09/14 01:34 PM 12/09/14 01:34 PM
Joined: Feb 2005 Posts: 28,312 Cincinnati, Ohio Challenger 1 Too Many Posts
Challenger 1 Too Many Posts Joined: Feb 2005 Posts: 28,312 Cincinnati, Ohio	Send it to Flanakin crankshaft in Huston Tx. He does byrant work and for many pros. He has done 3 bryant cranks for me and fast like in one or 2 days. He can weld them or whatever you need. web page

Re: Grinding a race crank [Re: GTS340] #1708312 12/09/14 01:44 PM 12/09/14 01:44 PM
Joined: Feb 2014 Posts: 655 Huntsville, AL A Airwoofer OP mopar
Airwoofer OP mopar A Joined: Feb 2014 Posts: 655 Huntsville, AL	Quote: Does Huntsville engines not grind cranks? There are a few trustworthy places in Detroit. I drive past their shop every day. Never see any work being done there besides wiring up tube racks. You should see the pile of cranks sitting on the floor. Gary Reavis is no longer there. Thanks for the other ideas guys.

Re: Grinding a race crank [Re: Airwoofer] #1708313 12/09/14 02:00 PM 12/09/14 02:00 PM
Joined: Feb 2005 Posts: 28,312 Cincinnati, Ohio Challenger 1 Too Many Posts
Challenger 1 Too Many Posts Joined: Feb 2005 Posts: 28,312 Cincinnati, Ohio	I see Flanakin is in Brownsburg Ind now, maybe a another shop? You know why?? Because he does all the pro byrant cranks, has been for many years. web page

Re: Grinding a race crank [Re: Challenger 1] #1708314 12/09/14 08:36 PM 12/09/14 08:36 PM
Joined: Jun 2004 Posts: 6,780 Alabama Mopar-Al master
Mopar-Al master Joined: Jun 2004 Posts: 6,780 Alabama	You don't trust Keith that does my cranks here? No nitride, he is very capable of putting the right number on them. I balance mine there to. What's the difference in rod weights and piston weights? I also left some mallory metal crank slugs over there on the shelf. I do my own stuff there ( back yard ) I guess you'd say. But they stay together and run like they should

Re: Grinding a race crank [Re: Mopar-Al] #1708315 12/10/14 02:24 PM 12/10/14 02:24 PM
Joined: Feb 2014 Posts: 655 Huntsville, AL A Airwoofer OP mopar
Airwoofer OP mopar A Joined: Feb 2014 Posts: 655 Huntsville, AL	He has a good crank grinding machine? You still coming up this weekend to mess with putting in the 540? I will play with the headers tonight to see if they have issues with interference.

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