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25w50 or straight 50 wt oil #1670500 09/13/14 04:35 AM 09/13/14 04:35 AM
Joined: Dec 2006 Posts: 4,647 aotearoa rebel OP master
rebel OP master Joined: Dec 2006 Posts: 4,647 aotearoa	any members running this weight oil in their rollercamed engines? my stock block street/strip car was having low oil problems from the fresh build. i figured it was due to the roller lifters bleeding past too easy so i fitted a restricter to the second gallery. this bumped up the pressure to more acceptable pressures but when it starts getting hot after a few rounds the pressure isn't making the mark. currently i'm running 15w40 semi synthetic oil & it was suggested i use 25w50 or straight 50 wt oil. i'm curious to who using it & what pressures do you experiance?

Re: 25w50 or straight 50 wt oil [Re: rebel] #1670501 09/13/14 12:01 PM 09/13/14 12:01 PM
Joined: Jul 2007 Posts: 1,682 Philadelphia R radar top fuel
radar top fuel R Joined: Jul 2007 Posts: 1,682 Philadelphia	I always ran 20/50 in the winter and straight 50 in my shovelhead harley. The straight weight seemed to keep the pressure up in the heat. Apples to oranges but fwiw the shovel is an air cooled roller tappet motor. I've run hydro and solid rollers in 'em. The newer harleys I always ran thinner oil.

Re: 25w50 or straight 50 wt oil [Re: radar] #1670502 09/13/14 12:09 PM 09/13/14 12:09 PM
Joined: Jan 2003 Posts: 32,394 Q Quicktree I Win
Quicktree I Win Q Joined: Jan 2003 Posts: 32,394	I think it's been stated many times, any attempt to control oil pressure by messing with different oil is a band aid to the problem.

Re: 25w50 or straight 50 wt oil [Re: rebel] #1670503 09/13/14 12:24 PM 09/13/14 12:24 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	Did you restrict rocker oiling?A welding tip in the rocker stand will work. GOTBOOST!New improved with Victor heads. http://www.enginelabs.com/mopar-big-bloc...t-of-necessity/

Re: 25w50 or straight 50 wt oil [Re: Clanton] #1670504 09/13/14 04:57 PM 09/13/14 04:57 PM
Joined: Mar 2010 Posts: 162 monticello,ms andy3965 member
andy3965 member Joined: Mar 2010 Posts: 162 monticello,ms	Quote: Did you restrict rocker oiling?A welding tip in the rocker stand will work. can you give more info on this? we have used the screw on terminal from a champion spark plug for this in the past. MOPAR BORN,MOPAR BRED,AND WHEN I DIE I'LL BE MOPAR DEAD!!!

Re: 25w50 or straight 50 wt oil [Re: andy3965] #1670505 09/13/14 06:04 PM 09/13/14 06:04 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	Quote: Quote: Did you restrict rocker oiling?A welding tip in the rocker stand will work. can you give more info on this? we have used the screw on terminal from a champion spark plug for this in the past. My pics are gone but I can let you know what to do.I have a better topic on it but can't find it from last summer.you cut off a mig tip to 1/2" after drilling it to what jet you want and install it in the rocker stand befor you put the bolt/stud in. https://board.moparts.org/ubbthreads/show...rue#Post7739265 Last edited by Clanton; 09/13/14 06:14 PM. GOTBOOST!New improved with Victor heads. http://www.enginelabs.com/mopar-big-bloc...t-of-necessity/

Re: 25w50 or straight 50 wt oil [Re: Quicktree] #1670506 09/13/14 08:37 PM 09/13/14 08:37 PM
Joined: Dec 2006 Posts: 4,647 aotearoa rebel OP master
rebel OP master Joined: Dec 2006 Posts: 4,647 aotearoa	Quote: I think it's been stated many times, any attempt to control oil pressure by messing with different oil is a band aid to the problem. if it's a band aid repair, why do they make so many different grade oils? i was advised by a dirt track racer to use the 50wt oil as most cars that race in his class use this weight oil due to the fact they're old school V8's & they all seem to have this problem when running solid roller cams. when i was using a solid flat tappet cam the oil pressure wasn't a problem but with just a cam change now it is.

Re: 25w50 or straight 50 wt oil [Re: rebel] #1670507 09/13/14 10:40 PM 09/13/14 10:40 PM
Joined: Jan 2003 Posts: 16,928 NC 440Jim I Live Here
440Jim I Live Here Joined: Jan 2003 Posts: 16,928 NC	It would be best to use roller lifters that don't have that problem. But before that, what is the oil pressure going down the track when "hot"? i.e. at 4000-7000 rpm. A Mopar big block high volume oil pump should put out tons of oil and the relief valve spring can be changed to regulate at a higher pressure. IMO, 70 psi is nice. But even 50 should be fine. I think 90 psi is too much. Idle pressure is not so important, and I feel 20 psi at 800 rpm is fine as long as the pressure goes up with rpm (maybe 35 psi at 2500 rpm). Also, what heads are you running? The Indy heads with external oil lines should be restricted to avoid excess oil to the heads, which also reduces oil pressure to the rest of the motor. Did the roller cam have the #4 journal grooved for more (too much) oil?

Re: 25w50 or straight 50 wt oil [Re: 440Jim] #1670508 09/13/14 11:17 PM 09/13/14 11:17 PM
Joined: Dec 2006 Posts: 4,647 aotearoa rebel OP master
rebel OP master Joined: Dec 2006 Posts: 4,647 aotearoa	Quote: It would be best to use roller lifters that don't have that problem. But before that, what is the oil pressure going down the track when "hot"? i.e. at 4000-7000 rpm. A Mopar big block high volume oil pump should put out tons of oil and the relief valve spring can be changed to regulate at a higher pressure. IMO, 70 psi is nice. But even 50 should be fine. I think 90 psi is too much. Idle pressure is not so important, and I feel 20 psi at 800 rpm is fine as long as the pressure goes up with rpm (maybe 35 psi at 2500 rpm). Also, what heads are you running? The Indy heads with external oil lines should be restricted to avoid excess oil to the heads, which also reduces oil pressure to the rest of the motor. Did the roller cam have the #4 journal grooved for more (too much) oil? i'm using Compcams offset roller lifters, i don't know of any other offset roller lifter that doesn't have an recessed oil band around the body. when the engine is really hot i found the oil press was only 50 psi @ 7k, not really what i was wanting, i'm a believer in 10 psi per 1k rpm on the safe side. when its cooler like on its first run it tops out at 75 psi which is acceptable in my books. the heads are stage VI & are fed from the cam. there is no groove in the bearing that feeds the rockers so it's not like Indys that need the restricter. the oil pump has a fat washer inder the spring to boost the pressure before the relief lets go.

Re: 25w50 or straight 50 wt oil [Re: rebel] #1670509 09/13/14 11:56 PM 09/13/14 11:56 PM
Joined: Jan 2007 Posts: 7,664 IN A ahy master
ahy master A Joined: Jan 2007 Posts: 7,664 IN	Since you said "street/strip" I'd pick 20W50 between the two. Its a decent 3 season oil and won't act like molasses on a cool'ish morning. As others have mentioned, if it's 50 PSI at speed with shimmed spring when hot something does not sound right. Does it have a HV pump? What are bearing clearances?

Re: 25w50 or straight 50 wt oil [Re: ahy] #1670510 09/14/14 06:26 AM 09/14/14 06:26 AM
Joined: Dec 2006 Posts: 4,647 aotearoa rebel OP master
rebel OP master Joined: Dec 2006 Posts: 4,647 aotearoa	yes HV pump, 0.002 crank n rod bearing clearences, new cam bearings. it's definately the lifter bores bleeding as it surprised me during the priming with the cordless drill. blocking 1 side bumped up the pressure a lot. when it was a solid FT cam the pressure was higher & the lifter bore bleeding was less, way less.

Re: 25w50 or straight 50 wt oil [Re: rebel] #1670511 09/14/14 11:21 AM 09/14/14 11:21 AM
Joined: May 2011 Posts: 4,489 northern,Ohio,USA C Clanton master
Clanton master C Joined: May 2011 Posts: 4,489 northern,Ohio,USA	Can you Mic both type of lifters you have? GOTBOOST!New improved with Victor heads. http://www.enginelabs.com/mopar-big-bloc...t-of-necessity/

Re: 25w50 or straight 50 wt oil [Re: rebel] #1670512 09/14/14 01:03 PM 09/14/14 01:03 PM
Joined: Jun 2006 Posts: 5,163 CT GTX MATT master
GTX MATT master Joined: Jun 2006 Posts: 5,163 CT	Quote: Quote: I think it's been stated many times, any attempt to control oil pressure by messing with different oil is a band aid to the problem. if it's a band aid repair, why do they make so many different grade oils? i was advised by a dirt track racer to use the 50wt oil as most cars that race in his class use this weight oil due to the fact they're old school V8's & they all seem to have this problem when running solid roller cams. when i was using a solid flat tappet cam the oil pressure wasn't a problem but with just a cam change now it is. Now I need to pin those needles, got to feel that heat Hear my motor screamin while I'm tearin up the street

Re: 25w50 or straight 50 wt oil [Re: Clanton] #1670513 09/14/14 04:51 PM 09/14/14 04:51 PM
Joined: Dec 2006 Posts: 4,647 aotearoa rebel OP master
rebel OP master Joined: Dec 2006 Posts: 4,647 aotearoa	Quote: Can you Mic both type of lifters you have? yes already checked that. the solid was 0.9032 & the roller is 0.9030

Re: 25w50 or straight 50 wt oil [Re: rebel] #1670514 09/14/14 05:40 PM 09/14/14 05:40 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: Quote: Can you Mic both type of lifters you have? yes already checked that. the solid was 0.9032 & the roller is 0.9030 And what are the lifter bores... .001 is pretty good for clearance... I'm at .0015

Re: 25w50 or straight 50 wt oil [Re: MR_P_BODY] #1670515 09/15/14 04:18 AM 09/15/14 04:18 AM
Joined: Dec 2006 Posts: 4,647 aotearoa rebel OP master
rebel OP master Joined: Dec 2006 Posts: 4,647 aotearoa	thats where things aren't so great with it being 0.0028 . they're all perfectly round but a tad big which is why i'm seeing the heavy bleed off with the priming pump.

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