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| | | Forums66 Topics128,014 Posts1,055,329 Members48,419 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Feb 2004 Posts: 7 New Guy | | New Guy Joined: Feb 2004 Posts: 7 | OK...... I pulled the 235 2 months ago. I am doing the Cliffords 6=8 mods. Bore out .060, different valves, mill the head .100, redo the valve train, the whole shebang as they advertise on their web site. The machinist doing the work told me I have no oil pressure galleries in the block to feed the hydraulic lifters (this was previously a solid lifter engine). He and I, am concerned, since I have purchased the hydraulic lifter/camshaft option. I have spoken with Cliffords, and they have assured me this setup will work fine, since the oil flowing down (via gravity and excess rocker arm flow) from the head/rocker arm area is sufficient to feed the hydraulic lifters. Anyone out there who has done this mod please let me know. I am concerned as to the actual functionality of this setup. If this is not going to work, I will have to return the camshaft, lifters, pushrods, and other parts. Thanks for any help. Tom | | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | I have a test engine (1941 235) that I did just what you are talking about for an experiment. There is no way for oil to enter the lifters from the top from 1953 on, so I vented the lifters on the top so oil could enter. I have only run this engine on a test stand, but it works fine there. In my blog post on hydraulic lifters I show venting lifters to allow air to escape, but the same thing can be done to allow oil to enter from the top. They make sealed, oil filled lifters for airplanes, that is what got me experimenting with 235 lifters. This idea would allow you to put hydraulic lifters in any Chev six back to 1929. That is when Chev started using this diameter lifter. I have never heard of any one else ever doing this, so if you do, I would love to hear the results.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Feb 2004 Posts: 29,746 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,746 | Why not just drill the block for an oil gallery to feed the lifters? Firearms makers do deep-hole drilling all the time- - - -it isn't that difficult. 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: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | A gentleman somewhere around LA made external oil lines to feed juice lifters on a GMC 6.
Ed
'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: 7 New Guy | | New Guy Joined: Feb 2004 Posts: 7 | I guess I am not real sure if the cliffords mod is viable. If anyone is out there that has done it this way, please let me know. Thanks. T O | | | | | Joined: Feb 2004 Posts: 29,746 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,746 | If a pressurized oil gallery really wasn't necessary to fill the lifters, why did Chevy go to the effort and expense to drill their blocks? Sometimes we should get back to basics and ask ourselves some hard questions, even if the answers aren't what we want to hear. 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: Dec 2008 Posts: 1,922 'Bolter | | 'Bolter Joined: Dec 2008 Posts: 1,922 | Clifford is completely wrong. The lifters are inflated by oil pressure constantly, which must enter through the feed hole in the "waisted" area. Pouring oil on top does nothing. The lifter will collapse (and shorten) if the pressure is interrupted even momentarily. When that happens, the pushrod is dropped to the new (lower) height, which adds a huge amount of lash to the rocker arm adjuster. If run like this, the parts will be ruined very quickly.
Don't even think about it. | | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 |
Last edited by Pre '68 Dave; 04/22/2016 3:12 AM.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Dec 2000 Posts: 3,399 Gas Pumper | | Gas Pumper Joined: Dec 2000 Posts: 3,399 | Gotta love the delete key! Hats off Dave! | | | | | Joined: Oct 2006 Posts: 1,847 'Bolter | | 'Bolter Joined: Oct 2006 Posts: 1,847 | it can be done, Gene Beck told be about it. But I don't know what exactly he did. | | | | | Joined: Oct 2009 Posts: 164 'Bolter | | 'Bolter Joined: Oct 2009 Posts: 164 | This is interesting to say the least. I'd be interested in this also. | | | | | Joined: Dec 2008 Posts: 1,922 'Bolter | | 'Bolter Joined: Dec 2008 Posts: 1,922 | | | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | On my test engine I sealed the original hole on the side to assure no oil escapes. I then vented the push-rod seat to be sure oil can enter from the top. On the test stand it works great. If you study the way a lifter works, they do not care how the oil gets to the reservoir.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Feb 2011 Posts: 170 Shop Shark | | Shop Shark Joined: Feb 2011 Posts: 170 | I just have to ask why would someone want to do this?? Scott | | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | For me, I have a lot of customers who do not, or are not setup to adjust there own valves. With hydraulic lifters you set them once and forget about them. That is one reason. Another is how quiet a hydraulic lifter engine is.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Mar 2010 Posts: 10,270 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,270 | I have a hydraulic lifter 235 and you need to just about stick your hand in the fan to make sure that it is still running.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Which hand - how many fingers do you have? | | | | | Joined: Dec 2000 Posts: 3,399 Gas Pumper | | Gas Pumper Joined: Dec 2000 Posts: 3,399 | Everyone comments how incredibly quiet my hydraulic 235 and 261 sound. | | |
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