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Oil pressure change w/ roller lifters in unbushed BB? #1462342 07/03/13 05:55 PM 07/03/13 05:55 PM
Joined: Jan 2003 Posts: 15,439 Val-haul-ass... eventually B BradH OP Taking time off to work on my car
BradH OP Taking time off to work on my car B Joined: Jan 2003 Posts: 15,439 Val-haul-ass... eventually	I'm wondering if people have seen a reduction in oil pressure when switching from flat-tappet lifters (hyd or solid) to solid roller lifters in OEM big blocks w/ unbushed lifter bores. FWIW, I'm going to be using the roller lifters that Brian @ IMM used to offer, which have a cut-out in the middle of the body comparable to the COMP 892s. Here's a picture of the IMM lifter, although mine have the offset intake pushrod seat.

Re: Oil pressure change w/ roller lifters in unbushed BB? [Re: BradH] #1462343 07/03/13 06:18 PM 07/03/13 06:18 PM
Joined: Jan 2003 Posts: 3,575 The Netherlands BigBlockMopar master
BigBlockMopar master Joined: Jan 2003 Posts: 3,575 The Netherlands	I went from flat tappets to a solid roller and noticed a pressure drop at warm idle, even though I have CompCams' 'fullbody' lifters. But I also exchanged 1.6 Crane gold rockers for 1.5 needlebearing rockers, so the pressure drop could also be a result from that. More likely the latter I would think. BigBlockMopar.com

Re: Oil pressure change w/ roller lifters in unbushed BB? [Re: BradH] #1462344 07/03/13 06:54 PM 07/03/13 06:54 PM
Joined: Jul 2004 Posts: 19,317 State of confusion T Thumperdart I Live Here
Thumperdart I Live Here T Joined: Jul 2004 Posts: 19,317 State of confusion	I did when I ran the Isky Red-zones because of the cutaway on the body like yours but now run the solid body lifter w/out issues. 72 Dart 470 n/a BB stroker street car `THUMPER`...Check me out on FB Dominic Thumper for videos and lots of carb pics......760-900-3895.....

Re: Oil pressure change w/ roller lifters in unbushed BB? [Re: Thumperdart] #1462345 07/03/13 08:01 PM 07/03/13 08:01 PM
Joined: Jan 2003 Posts: 2,152 Fancy Farm Ky W wyoming top fuel
wyoming top fuel W Joined: Jan 2003 Posts: 2,152 Fancy Farm Ky	It would depend on how much lift you are going to run on the cam, I used to run the Cranes with the cutaways, and they were fine with a .625 cam, had room to spare, now run solid body with a .675 cam, I think the Cranes would have worked fine with the bigger cam also, they were replaced because they just finally wore out, no complaints on that though, I had bought them used.

Re: Oil pressure change w/ roller lifters in unbushed BB? [Re: Thumperdart] #1462346 07/03/13 08:13 PM 07/03/13 08:13 PM
Joined: May 2013 Posts: 80 new york 6 68HEMIRR member
68HEMIRR member 6 Joined: May 2013 Posts: 80 new york	Quote: I did when I ran the Isky Red-zones because of the cutaway on the body like yours but now run the solid body lifter w/out issues. you run a solid body isky rollers?....or what lifters are you running now?.....i am dumping my schubeck ceramic solid lifters and going with solid rollers......just curious...thanks BORN TO BE WILD

Re: Oil pressure change w/ roller lifters in unbushed BB? [Re: 68HEMIRR] #1462347 07/03/13 09:57 PM 07/03/13 09:57 PM
Joined: Dec 2007 Posts: 12,587 Great Neck,LI,new york hemi-itis I Live Here
hemi-itis I Live Here Joined: Dec 2007 Posts: 12,587 Great Neck,LI,new york	I use Comp 848's in my engine and a friends stock block 440.Lost 15 lbs of OP hot.Last time I freshened my hemi after 3 years of abuse,had restrictors installed in the pushrods and got that 15 lbs back. HEMI-ITIS has no cure. My condition is fully BLOWN!!

Re: Oil pressure change w/ roller lifters in unbushed BB? [Re: hemi-itis] #1462348 07/03/13 10:02 PM 07/03/13 10:02 PM
Joined: May 2011 Posts: 4,489 northern,Ohio,USA C Clanton master
Clanton master C Joined: May 2011 Posts: 4,489 northern,Ohio,USA	I run the solid body comps and psi was fine and even put a restrictor in the ds rear oil galley when I had a stock block. GOTBOOST!New improved with Victor heads. http://www.enginelabs.com/mopar-big-bloc...t-of-necessity/

Re: Oil pressure change w/ roller lifters in unbushed BB? [Re: hemi-itis] #1462349 07/03/13 10:04 PM 07/03/13 10:04 PM
Joined: Feb 2011 Posts: 4,302 Nebraska 72Swinger master
72Swinger master Joined: Feb 2011 Posts: 4,302 Nebraska	Anyone ever use these towards the bottom of the page? http://www.mrlperformance.com/ Mopar to the bone!!!

Re: Oil pressure change w/ roller lifters in unbushed BB? [Re: 72Swinger] #1462350 07/03/13 11:11 PM 07/03/13 11:11 PM
Joined: Mar 2006 Posts: 9,836 MI, usa dvw master
dvw master Joined: Mar 2006 Posts: 9,836 MI, usa	For what it's worth I have bushed lifter bores. With push rod oil (.080 holes in the pushrods) and .003" bearing clearance I couldn't make over 40 psi hot w/ vacuum pump at 10psi. Reducing the the lifter feed holes from 2 @.110 to 1 @.040 I then had to back off the oil pump relief valve adjustment .200" to get back down to 70psi. Just shows you how much volume you can lose in that area. Doug

Re: Oil pressure change w/ roller lifters in unbushed BB? [Re: 68HEMIRR] #1462351 07/04/13 01:41 AM 07/04/13 01:41 AM
Joined: Jul 2004 Posts: 19,317 State of confusion T Thumperdart I Live Here
Thumperdart I Live Here T Joined: Jul 2004 Posts: 19,317 State of confusion	Quote: Quote: I did when I ran the Isky Red-zones because of the cutaway on the body like yours but now run the solid body lifter w/out issues. you run a solid body isky rollers?....or what lifters are you running now?.....i am dumping my schubeck ceramic solid lifters and going with solid rollers......just curious...thanks Yes, solid body Isky`s that have been rebuilt once............. 72 Dart 470 n/a BB stroker street car `THUMPER`...Check me out on FB Dominic Thumper for videos and lots of carb pics......760-900-3895.....

Re: Oil pressure change w/ roller lifters in unbushed BB? [Re: Thumperdart] #1462352 07/04/13 07:29 AM 07/04/13 07:29 AM
Joined: Feb 2006 Posts: 1,051 The Great White North RAMM super stock
RAMM super stock Joined: Feb 2006 Posts: 1,051 The Great White North	With those lifters in the picture you will experience low oil pressure at idle. The good news is that it doesn't cause any damage. I have done multiple inspections on big blocks with 15-20 lbs idle oil pressure with those lifters and the bearings looked new. I would still look into bushing the bores or a full body lifter at the right diameter. J.Rob 2009 PHR\EMC Competitor 2010 PHR\EMC Competitor 2011 PHR\EMC Competitor 2012 PHR\EMC Competitor 2013 PHR\EMC Competitor 2014 HotRod/EMC Competitor 2015 HotRod/EMC NoShow 2016 HotRod/EMC 3rd place SPEC Bigblock 2018 HotRod/EMC 7th place G3

Re: Oil pressure change w/ roller lifters in unbushed BB? [Re: RAMM] #1462353 07/04/13 11:41 AM 07/04/13 11:41 AM
Joined: Jan 2003 Posts: 15,439 Val-haul-ass... eventually B BradH OP Taking time off to work on my car
BradH OP Taking time off to work on my car B Joined: Jan 2003 Posts: 15,439 Val-haul-ass... eventually	If there was such a thing as a full-body lifter w/ offset intake seats and EDM oiling of the bearings, that would be the hot setup. There may be something out there now that fits that description, but with my luck it's a $1000 set of lifters... I don't need pushrod oiling, but the other features would fit my application better IF the cut-out band is (and this seems to be a point of contention) the reason for the difference in oil pressure. Some builders say the cutout results in the lower oil pressure, while others have said that problem is a result of the lifter body not extending far enough down over the roller itself, thus exposing the oil gallery in the lifter bore to an open passage at peak lifter rise. I'm looking at a cam w/ a .434" lobe lift, so that "should" still be in the safe range from what I recall discussing w/ Brian when I purchased the lifters. This will be my first "roller rodeo", so I have to admit ignorance on the issue and am trying to be prepared for what may result.

Re: Oil pressure change w/ roller lifters in unbushed BB? [Re: BradH] #1462354 07/04/13 12:05 PM 07/04/13 12:05 PM
Joined: Jan 2003 Posts: 16,925 NC 440Jim I Live Here
440Jim I Live Here Joined: Jan 2003 Posts: 16,925 NC	I don't know if you have the original IMM lifters or the revised ones. One was noticably taller than the other (2.25" compared to 1.78" in my picture of Comp 892) FWIW, this is what I measured on Comp 892. No noticable problem with a 0.434" lobe lift. But I didn't idle the car much to observe it either. I do remember doing a check when putting them in the 400 block. The oil galley was nowhere near being exposed at max lift or the base circle. 7765146-Comp_892_roller_lifter_ruler2.jpg (231 downloads)

Re: Oil pressure change w/ roller lifters in unbushed BB? [Re: 440Jim] #1462355 07/05/13 01:27 PM 07/05/13 01:27 PM
Joined: Jan 2003 Posts: 15,439 Val-haul-ass... eventually B BradH OP Taking time off to work on my car
BradH OP Taking time off to work on my car B Joined: Jan 2003 Posts: 15,439 Val-haul-ass... eventually	FWIW, I put a cam in my unbushed 451 block and dropped all the IMM lifters in to try and determine whether that cam / lifter / block combination was exposing the lifter bore oil gallery openings at peak lobe lift. If my measurements are reasonably accurate (some of them are "eyeballed" by putting vernier down into the lifter bores, this particular parts combination appears to be leaving the bottom of the oil gallery passage covered by approx. .080" of lifter skirt... at least on the bore that I measured. Knowing how much variance the old Chrysler castings have, I can see where this might be hit-or-miss on whether each lifter / bore combination manages to cover the oil gallery passage at all times, or allows a small opening as the lobe reaches peak lift. As Brian @ IMM mentioned previously (older thread), he's suggested some of his customers to have cams ground on smaller diameter base circles to reduce the likelihood of this happening. I'd have to measure the base circle on this particular cam to get any reference # for comparison, and wouldn't know w/o other people providing additional measurements on whether what I have falls into the "big", "average" or "small" base circle.

Re: Oil pressure change w/ roller lifters in unbushed BB? [Re: 440Jim] #1462356 07/05/13 01:33 PM 07/05/13 01:33 PM
Joined: Jan 2003 Posts: 15,439 Val-haul-ass... eventually B BradH OP Taking time off to work on my car
BradH OP Taking time off to work on my car B Joined: Jan 2003 Posts: 15,439 Val-haul-ass... eventually	Quote: I don't know if you have the original IMM lifters or the revised ones. Actually, I have a set of each, both w/ the offset intake pushrod seats. The revised "short body" set I purchased new directly from Brian. The original "long body" set I purchased as low-use used units from Jason Nimitz. Other than the extended height of the body above the pushrod seats, the rest of the dimensions are identical from what I can tell. I prefer the "long body" style because I believe they're more stable in the lifter bores, but haven't seen those around since Brian sold out of the original lifters before I bought some from his later inventory.

Re: Oil pressure change w/ roller lifters in unbushed BB? [Re: BradH] #1462357 07/05/13 01:37 PM 07/05/13 01:37 PM
Joined: Jan 2003 Posts: 15,439 Val-haul-ass... eventually B BradH OP Taking time off to work on my car
BradH OP Taking time off to work on my car B Joined: Jan 2003 Posts: 15,439 Val-haul-ass... eventually	For the people who have seen a reduction in oil pressure, is this only at apparent idle, or does it reduce the pressure across the entire RPM range? I figured if it's across the whole RPM range, running a stiffer oil pressure relief spring might help to band-aid the reduced pressure.

Re: Oil pressure change w/ roller lifters in unbushed BB? [Re: BradH] #1462358 07/05/13 02:06 PM 07/05/13 02:06 PM
Joined: Mar 2003 Posts: 9,100 Rogue River, OR Jeremiah master
Jeremiah master Joined: Mar 2003 Posts: 9,100 Rogue River, OR	One of the many reason I am putting 1.7 ratio rockers on my 511 is the ability to use a smaller base circle cam.

Re: Oil pressure change w/ roller lifters in unbushed BB? [Re: BradH] #1462359 07/05/13 03:03 PM 07/05/13 03:03 PM
Joined: Sep 2003 Posts: 1,049 San Jose Ca. boatracer572 super stock
boatracer572 super stock Joined: Sep 2003 Posts: 1,049 San Jose Ca.	Quote: For the people who have seen a reduction in oil pressure, is this only at apparent idle, or does it reduce the pressure across the entire RPM range? I figured if it's across the whole RPM range, running a stiffer oil pressure relief spring might help to band-aid the reduced pressure. The problem isn't pressure, it's volume , un bushed lifter bores allow to much volume to feed the top end in most mopar applications. you can put the stiffest oil pump spring you can find, if there's not enough volume you will never build a ton of pressure... 7766258-image.jpg (350 downloads) Last edited by boatracer572; 07/05/13 03:10 PM.

Re: Oil pressure change w/ roller lifters in unbushed BB? [Re: boatracer572] #1462360 07/06/13 09:35 AM 07/06/13 09:35 AM
Joined: Jan 2003 Posts: 15,439 Val-haul-ass... eventually B BradH OP Taking time off to work on my car
BradH OP Taking time off to work on my car B Joined: Jan 2003 Posts: 15,439 Val-haul-ass... eventually	Quote: Quote: ... un bushed lifter bores allow to much volume to feed the top end in most mopar applications... But that only applies if you're working w/ lifters where the pushrod oil feed ports are exposed to the oil gallery most/all of the time. The issue I'm talking about is when the lifter body rises enough to momentarily expose the oil gallery at full lobe lift, which wouldn't have any impact on the amount of oil being pumped up to the top end.

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