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| | | | Joined: Apr 2008 Posts: 643 'Bolter | | 'Bolter Joined: Apr 2008 Posts: 643 | Are the ID's of Harmonic balancers the same? meaning a 2 groove 292 hb will fit on a 235 or 302.Someone told me the snouts are all the same diameter; just a matter of lining them up??
Danny
1958 GMC stepside GMC 302 six cylinder 3 speed OD trans
| | | | | Joined: Feb 2004 Posts: 29,756 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,756 | All of the 216/235/261/engine crankshafts have a 1 1/4" snout diameter and a 1 3/4" diameter seal surface. Ditto for all the 2nd. generation sixes- - - -194, 230, 250, and 292. Small block V8's also share those dimensions. The balancer/pulley setup I make uses a 6" diameter V8 balancer with a big block V8 2-groove pulley inverted over it. It requires some machining to get the length of the snout right and some work on the depth of the OD. A 250 balancer can be modified the same way, but since the belt driving stress is carried by the rubber isolator ring, I'm not very impressed with that setup. The balancer ring on the V8 damper is not stressed, the way I do it.
Yes, the balancers will interchange- - - - -no, it's not a drop-in swap.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Apr 2008 Posts: 643 'Bolter | | 'Bolter Joined: Apr 2008 Posts: 643 | You mentioned all Chevy engines. What about the GMC's? I have a Chevy235 and a GMC302 that I am planning on adding A/C to both.
I think Davis Speed offers a bracket kit for both; but am wondering about the much needed double grooved harmonic balancer issue-
Danny
1958 GMC stepside GMC 302 six cylinder 3 speed OD trans
| | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | I put a 2 pulley balancer for a 292 on a 302, had to shorten the snout some, no big deal.
Ed
Last edited by EdPruss; 02/27/2018 12:55 PM.
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Feb 2004 Posts: 29,756 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,756 |
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Feb 2004 Posts: 29,756 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,756 | You mentioned all Chevy engines. What about the GMC's? Measure the diameter of the GMC crankshaft snout. If it's 1.25" a Chevy balancer can be adapted. I don't have a GMC crank handy to measure- - - - -you do. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Apr 2008 Posts: 643 'Bolter | | 'Bolter Joined: Apr 2008 Posts: 643 | Ok, thanks for the info.My 302 has a 235 single groove hb on it .
Danny
1958 GMC stepside GMC 302 six cylinder 3 speed OD trans
| | | | | Joined: Feb 2004 Posts: 29,756 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,756 | If it's got a 235 balancer on it now, the crank snout will have the same dimensions as "all the above" engines. Like Mr. Spock says "It's logical!"
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Apr 2008 Posts: 643 'Bolter | | 'Bolter Joined: Apr 2008 Posts: 643 |
Danny
1958 GMC stepside GMC 302 six cylinder 3 speed OD trans
| | | | | Joined: Jul 2016 Posts: 1 Moderated | | Moderated Joined: Jul 2016 Posts: 1 | Has anybody made a serpentine belt set up on a later 235? Currently have a single belt HB driveing water pump and power steering pump, then i drive my alternator from the second pully on the power steering pump. This setup seems weak as everything gets its power from the 1 belt on the HB. Been thinking about a better system. | | |
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