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Is .002" rod bearing clearance to tight ? #1222455 04/26/12 02:32 AM 04/26/12 02:32 AM
Joined: Feb 2006 Posts: 146 Wis. R rlm2268 OP member
rlm2268 OP member R Joined: Feb 2006 Posts: 146 Wis.	Do You think .002" rod bearing clearance is to tight for a street strip type 500" motor turning 6500-6800 rpm. Or should I try and get another bearing set in .001 looser and use half the set or the whole set to try to get it .0025"-.003" p.s my bearings are clevite CB-527 HD .

Re: Is .002" rod bearing clearance to tight ? [Re: rlm2268] #1222456 04/26/12 02:40 AM 04/26/12 02:40 AM
Joined: Jan 2004 Posts: 903 Saskatchewan, Canada cudabin super stock
cudabin super stock Joined: Jan 2004 Posts: 903 Saskatchewan, Canada	I would shoot for .0025" to .003", 3/4 groove King Alelecular bearings are great! Cheers, Arnie 67 Cuda 8.48@ 158.7 mph 1.18 60' 2,600 DA(so far...) 70 Super Bee 440 Six Pack 4-speed. 13.2 @ 104 Stock exhaust/Street tires.

Re: Is .002" rod bearing clearance to tight ? [Re: rlm2268] #1222457 04/26/12 04:24 AM 04/26/12 04:24 AM
Joined: Apr 2004 Posts: 1,056 Mt.Vernon IL Twin Turbo Mower super stock
Twin Turbo Mower super stock Joined: Apr 2004 Posts: 1,056 Mt.Vernon IL	Quote: Do You think .002" rod bearing clearance is to tight for a street strip type 500" motor turning 6500-6800 rpm. Or should I try and get another bearing set in .001 looser and use half the set or the whole set to try to get it .0025"-.003" p.s my bearings are clevite CB-527 HD . Yes too tight buy the .001 loser and you will be fine. My friend did the same thing been running his 511 for 3 years now.

Re: Is .002" rod bearing clearance to tight ? [Re: rlm2268] #1222458 04/26/12 09:44 AM 04/26/12 09:44 AM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	How did you read the clearance... mics or plastigauge

Re: Is .002" rod bearing clearance to tight ? [Re: MR_P_BODY] #1222459 04/26/12 09:49 AM 04/26/12 09:49 AM
Joined: Mar 2007 Posts: 12,008 Finally a HUSKER again Moparnut426 I Live Here
Moparnut426 I Live Here Joined: Mar 2007 Posts: 12,008 Finally a HUSKER again	I agree what did ya use plasti guage or did ya use a micrometer? and Honestly depending on how much ya pound on it, 2 would be fine as long as ya know to use correct oil with that clearance. My first 360 was 2 mains and 1.5 rods, and its still fine. Im not nice to that engine at all, and its living fine. Kasey

Re: Is .002" rod bearing clearance to tight ? [Re: MR_P_BODY] #1222460 04/26/12 09:54 AM 04/26/12 09:54 AM
Joined: Feb 2006 Posts: 146 Wis. R rlm2268 OP member
rlm2268 OP member R Joined: Feb 2006 Posts: 146 Wis.	Hi, I used a mic. on the crank and used a snap type guage on the rods and measured it with the mic. My full groove mains came out between .0025-003

Re: Is .002" rod bearing clearance to tight ? [Re: rlm2268] #1222461 04/26/12 10:00 AM 04/26/12 10:00 AM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	There is a rule of thumb for clearance... its something like .001 per every inch of diameter (dont quote me on that number... I forget what it is)

Re: Is .002" rod bearing clearance to tight ? [Re: MR_P_BODY] #1222462 04/26/12 10:09 AM 04/26/12 10:09 AM
Joined: Jan 2012 Posts: 2,625 Stuttgart, Arkansas rickseeman master
rickseeman master Joined: Jan 2012 Posts: 2,625 Stuttgart, Arkansas	The book says 2 to 3 so you are in spec....you are just tight. 2011 Drag Pak Challenger

Re: Is .002" rod bearing clearance to tight ? [Re: rlm2268] #1222463 04/26/12 10:23 AM 04/26/12 10:23 AM
Joined: Aug 2003 Posts: 11,179 Atco NJ DJVCuda I Live Here
DJVCuda I Live Here Joined: Aug 2003 Posts: 11,179 Atco NJ	Quote: Hi, I used a mic. on the crank and used a snap type guage on the rods and measured it with the mic. My full groove mains came out between .0025-003 better to be a little loose then a little tight. were you able to repeat the results with the snap gauge? I find it difficult to get that precise with them and prefer to use an inside mic to be exact.

Re: Is .002" rod bearing clearance to tight ? [Re: MR_P_BODY] #1222464 04/26/12 12:04 PM 04/26/12 12:04 PM
Joined: Feb 2007 Posts: 5,080 organ M maximum entropy master
maximum entropy master M Joined: Feb 2007 Posts: 5,080 organ	Quote: There is a rule of thumb for clearance... its something like .001 per every inch of diameter (dont quote me on that number... I forget what it is) what's your rod journal diameter? for what is the good life if not doing things thoughtfully?

Re: Is .002" rod bearing clearance to tight ? [Re: rlm2268] #1222465 04/26/12 12:54 PM 04/26/12 12:54 PM
Joined: Jan 2003 Posts: 15,439 Val-haul-ass... eventually B BradH Taking time off to work on my car
BradH Taking time off to work on my car B Joined: Jan 2003 Posts: 15,439 Val-haul-ass... eventually	If you go for the 'X' bearings w/ the additional .001" clearance, be prepared to spend about twice what the standard size bearings cost.

Re: Is .002" rod bearing clearance to tight ? [Re: rlm2268] #1222466 04/26/12 01:05 PM 04/26/12 01:05 PM
Joined: Feb 2005 Posts: 370 Real North Cal. 6 66er enthusiast
66er enthusiast 6 Joined: Feb 2005 Posts: 370 Real North Cal.	.002 will be fine. That what my engine is set up with and it has 500+ passes on it shifting at 6800 RPMs. I just rolled new bearing in it this winter, but I think that I could have just kept running the old ones. I like them to have .003 on the main and .002 on the rod to keep the oil pressure up at the rods. do you have Mopar or Chevy size?

Re: Is .002" rod bearing clearance to tight ? [Re: 66er] #1222467 04/26/12 01:17 PM 04/26/12 01:17 PM
Joined: Aug 2003 Posts: 43,088 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,088 Bend,OR USA	Quote: do you have Mopar or Chevy size? The CB527 sereis bearings are for the standard BB Mopar rod journals, 2.375 diameter. The HD are narrower, and have a chamfer on the crank side ,than the standard rod bearings are OP, your crank rod journals must be ground on the large size of the specs, usually when I used the HD bearings I ended up with .003 to .0038 clearances thats using a inside mike to get the diameter and then using the outside mike to see what size it was on the inside of the bearing. I now have several dial bore gauges and they are easier to see the clearances once you get them set up, modern technology OP ,a lot looser (.0005) is better than a tiny bit to tight(.0001) Last edited by Cab_Burge; 04/26/12 07:10 PM.

Re: Is .002" rod bearing clearance to tight ? [Re: Cab_Burge] #1222468 04/26/12 01:25 PM 04/26/12 01:25 PM
Joined: Feb 2005 Posts: 370 Real North Cal. 6 66er enthusiast
66er enthusiast 6 Joined: Feb 2005 Posts: 370 Real North Cal.	Quote: Quote: do you have Mopar or Chevy size? The CB527 sereis bearings are for the standard BB Mopar rod journals, 2.375 diameter. The HD are narrower, and have a chamfer on the crank side ,than the standard rod bearings are OP, your crank rod journals must be ground on the large size of the specs, usually when I used the HD bearings I ended up with .003 to .0038 clearances thats using a inside mike to get the diameter and then using the outside mike to see what size it was on the inside of the bearing. I now have several dial bore gauges and they are easier to see the clearances once you get them set up, modern technology Yep, I see that now. I missed the number when I read the post

Re: Is .002" rod bearing clearance to tight ? [Re: 66er] #1222469 04/26/12 10:52 PM 04/26/12 10:52 PM
Joined: Feb 2006 Posts: 146 Wis. R rlm2268 OP member
rlm2268 OP member R Joined: Feb 2006 Posts: 146 Wis.	Hi, thank's for the imput, with the mic. on the crank journals I come up with 2.3745 and using a snap guage on the inside of the rod I come up with 2.3765 with the clevite 527 hd bearings I see you weren't kidding on the cost of the X .001 bearings, like around $200.00 for rod bearings now what to do?

Re: Is .002" rod bearing clearance to tight ? [Re: rlm2268] #1222470 04/26/12 11:57 PM 04/26/12 11:57 PM
Joined: Aug 2003 Posts: 43,088 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,088 Bend,OR USA	You do have the rods torque down to the specs your going to use in the motor, hopefully If not do that now Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: Is .002" rod bearing clearance to tight ? [Re: Cab_Burge] #1222471 04/27/12 12:13 AM 04/27/12 12:13 AM
Joined: Feb 2006 Posts: 146 Wis. R rlm2268 OP member
rlm2268 OP member R Joined: Feb 2006 Posts: 146 Wis.	Yes rods were torqued when measured, short block is acually assembled and ran into a side clearance issue on 7 and 8 rod, figured that out the bearing must have been slightly touching the crank fillet, scraped the bearing a little on the chamfer side and now the side clearance is the same as the rest but now having second thoughts about the bearing clearance.

Re: Is .002" rod bearing clearance to tight ? [Re: rlm2268] #1222472 04/27/12 11:26 AM 04/27/12 11:26 AM
Joined: Jan 2003 Posts: 15,439 Val-haul-ass... eventually B BradH Taking time off to work on my car
BradH Taking time off to work on my car B Joined: Jan 2003 Posts: 15,439 Val-haul-ass... eventually	Quote: ... I see you weren't kidding on the cost of the X .001 bearings, like around $200.00 for rod bearings now what to do? Unfortunately, nobody ever said this hobby was cheap... or that all the "right" parts will always bolt together w/o any unforseen hassles. I do feel your pain...

Re: Is .002" rod bearing clearance to tight ? [Re: rlm2268] #1222473 04/27/12 11:48 AM 04/27/12 11:48 AM
Joined: Feb 2005 Posts: 370 Real North Cal. 6 66er enthusiast
66er enthusiast 6 Joined: Feb 2005 Posts: 370 Real North Cal.	Check it with plastigauge. If it still measures at .002 then run it. In the Mopar Performance manual, it list the connecting rod clearance .001-.003 I would never set a engine up with .001 clearance, but it has been done and the engines survived. I would not sweat it, .002 is fine, you are rite in the middle of the spec. Plastigauge is not the most high tech method , but it can confirm your snap gauge reading.

Re: Is .002" rod bearing clearance to tight ? [Re: 66er] #1222474 04/27/12 01:02 PM 04/27/12 01:02 PM
Joined: Feb 2006 Posts: 146 Wis. R rlm2268 OP member
rlm2268 OP member R Joined: Feb 2006 Posts: 146 Wis.	Thank's again for everyones imput FYI i did some seaching while I was deciding what to do and wanted to pass along to you guys needing the cb527HXND .001 X bearings, summit wants like $200.00 for a set and jegs is a little more But Competition Products in Oshkosh Wis. has them for $82.99 on there website

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