to much oil pressure?

Posted By: dcr

to much oil pressure? - 09/25/11 02:05 AM

Over labor day weekend I broke a timing chain on my 512 Looked at everything closely could not find a reason for it to break cam turns freely no push rod interferance etc figured I just got a bad chain and replaced it with a roll master timing set this time when I got it running today decided I would spend a little time trying to lower oil pressure I dont figure it really needs 85-90 psi at a hot idle pump is a mellings high volume not a high pressure pump removed bypass spring and replaced it with one from a stock pump that lowered pressure down to 75 psi hot idle would think about 40 psi would be more then enough and probley about right and about 80 through traps before I start cutting springs does anybody have any suggestions on how to lower pressure and the big question could this have caused my timing chain failure alittle info bearing clearance is about .003-.0035 and Im running 20-50 brad penn maybe I should go to a 10-30 or is that high of pressure good.With my chevies I always followed the 10 psi to 1000 rpm rule wth alittle extra for assurace.Oh and my filter is a wix hp.

Posted By: 71440dart

Re: to much oil pressure? - 09/25/11 02:14 AM

i know milidon sells an externally adjustable oil pressure regulator, part number 21550.

Posted By: MR_P_BODY

Re: to much oil pressure? - 09/25/11 02:22 AM

Put in lighter oil first and see where its at... all
that pressure is just eating power

Posted By: AndyF

Re: to much oil pressure? - 09/25/11 05:06 AM

Swap in a standard volume pump. You are just wasting power recirculating oil with that high volume pump.

Posted By: Chris'sBarracuda

Re: to much oil pressure? - 09/25/11 07:48 AM

Quote:

Put in lighter oil first and see where its at... all
that pressure is just eating power

Quote:

Swap in a standard volume pump. You are just wasting power recirculating oil with that high volume pump.

I'm not buying that argument at all.

I tried a back to back run deal years ago.

Ran the car with max oil pressure and 20W-50 oil.. 100 psi.

Then drained the oil and put in 10W-30 in it. (both synthetic and same brand).. Also backed off the oil pressure with the adjustable spring. 70 psi.

The car went actually slower by .005..

And that was just due to the difference in DA..

You may see a difference on the dyno, but you wont see anything on the race track..

Just my

Chris..

Posted By: sixpackgut

Re: to much oil pressure? - 09/25/11 08:11 AM

at what pressure do you blow thru the bypass in the filter?

Posted By: Chris'sBarracuda

Re: to much oil pressure? - 09/25/11 08:26 AM

Quote:

at what pressure do you blow thru the bypass in the filter?

Good question Ray..

I have used both K & N and System 1.. Don't know what the bypass is on either..

I just did that test years ago to see for myself.. I was always told that all that oil pressure was slowing me down sooooo much..

Not True..

My B1 now has about 90-95# cold and through the traps. But goes down to 35-40# @ idle after a run..

Chris..

Posted By: 440Jim

Re: to much oil pressure? - 09/25/11 09:40 AM

First, remember "hot" water temp is not hot oil temp. It can take a lot of running to get the oil temp hot.

My 511 CID race engine is setup to run 75 psi going down the track with oil temp 130-150 F. At 1200 rpm idle it is around 40-50 psi depending on oil temp.

My 440 CID street car has 60 psi driving down the road with hot oil (150-200) and 25 psi at 800 rpm idle. This one has higher cold oil pressures around 85 psi at 2000 rpm until the oil gets warmer.

I also did a test with a standard volume pump and high volume pump. This was not back to back the same day, but I was convinced of the results with all the data I have on my race car. No significant ET difference. I even used the same bypass spring in both pumps so the down track pressure was the same. Of course the idle pressure was different. Maybe a stock class racer might find 0.01 seconds in a lower hp engine.

Posted By: dcr

Re: to much oil pressure? - 09/25/11 01:25 PM

Thanks for the replys,Does anyone think this may have contributed to my timing chain failure? Im not real concerned about power output I know it will be small if any gains but it seems it would overheat the oil.But I can see this putting extra load on the dist drive which would be putting load on timing chain weather it would be enough to break it is the question. thanks Dan

Posted By: Chris'sBarracuda

Re: to much oil pressure? - 09/25/11 01:55 PM

NO..

Guys run chains with near 950# open spring pressure.

That would be much more strain on the timing chain..

How did you not hit a valve when it broke? Or did you..

Chris..

Posted By: dcr

Re: to much oil pressure? - 09/25/11 02:12 PM

No I dident hit a valve I hit 15 valves and figured I may as well replace the good one to

There were some light marks on the piston luckily when I had valve notchs cut I told them to go as deep as possiable for future cam upgrades I figure that probebly save some major carnage being how it was top of second gear at 7000 rpm when it broke.Tore it all down every thing looks fine but I am still a little gun shy. This is a new car and engine for me even switched brands I started with a 64 dodge 25 years ago played with chevies and cam back to mopar were I plan on staying.First race lost a trans,second lost timing chain Havent even had a oppertunity to tune this thing yet but it went 10.35 @ 130 first time out I guess if I have everything right may not have much to gain but I dont believe Im that good Like to see this 3200 lbs pump gas duster break into the 9s.

Posted By: rickstershemi

Re: to much oil pressure? - 09/25/11 02:30 PM

Sorry to jump in with a question: But my new 408" has what I would say unusual high oil pressure...75# - 80# at idle completely warmed up....I switched from 20/50 to 10/30 as suggested in another thread and it did lower it to 65# - 70# but still climbs to 100# as the rpms climb? It does have a Mellings HV pump and also we threw a 90* oil filter adapter on it as it was all we had lying around....it is untouched (meaning it has never had any of the neat tricks I've read about done to it to improve flow). I also run a Wix 51515R filter.

Motor seems to be getting plenty of lubrication where neede.

Could the 90* adapter be the problem or at least part of the problem...??????

Or am I just overly concerned...??????

Thanks in advance,

Rickster

Posted By: MR_P_BODY

Re: to much oil pressure? - 09/25/11 02:38 PM

Quote:

Sorry to jump in with a question: But my new 408" has what I would say unusual high oil pressure...75# - 80# at idle completely warmed up....I switched from 20/50 to 10/30 as suggested in another thread and it did lower it to 65# - 70# but still climbs to 100# as the rpms climb? It does have a Mellings HV pump and also we threw a 90* oil filter adapter on it as it was all we had lying around....it is untouched (meaning it has never had any of the neat tricks I've read about done to it to improve flow). I also run a Wix 51515R filter.

Could the 90* adapter be the problem or at least part of the problem...??????

Or am I just overly concerned...??????

Thanks in advance,

Rickster

Doubtful on the 90* filter mount... my big concern
would be possibly blowing out a filter or filter
base O-ring... I ran a stock 90* mount and never had
any where near that pressure

Posted By: dusturbd340W5

Re: to much oil pressure? - 09/25/11 02:40 PM

Quote:

Sorry to jump in with a question: But my new 408" has what I would say unusual high oil pressure...75# - 80# at idle completely warmed up....I switched from 20/50 to 10/30 as suggested in another thread and it did lower it to 65# - 70# but still climbs to 100# as the rpms climb? It does have a Mellings HV pump and also we threw a 90* oil filter adapter on it as it was all we had lying around....it is untouched (meaning it has never had any of the neat tricks I've read about done to it to improve flow). I also run a Wix 51515R filter.

Motor seems to be getting plenty of lubrication where neede.

Could the 90* adapter be the problem or at least part of the problem...??????

Or am I just overly concerned...??????

Thanks in advance,

Rickster

I had the same problem on my 416 with the melling HV I took it off and threw it in the trash and went with a standard pump problem solved.I still have 35-40 at idle with oil at 160 and 80 in the traps.

Posted By: Guitar Jones

Re: to much oil pressure? - 09/25/11 02:53 PM

Quote:

Quote:

Sorry to jump in with a question: But my new 408" has what I would say unusual high oil pressure...75# - 80# at idle completely warmed up....I switched from 20/50 to 10/30 as suggested in another thread and it did lower it to 65# - 70# but still climbs to 100# as the rpms climb? It does have a Mellings HV pump and also we threw a 90* oil filter adapter on it as it was all we had lying around....it is untouched (meaning it has never had any of the neat tricks I've read about done to it to improve flow). I also run a Wix 51515R filter.

Motor seems to be getting plenty of lubrication where neede.

Could the 90* adapter be the problem or at least part of the problem...??????

Or am I just overly concerned...??????

Thanks in advance,

Rickster

I had the same problem on my 416 with the melling HV I took it off and threw it in the trash and went with a standard pump problem solved.I still have 35-40 at idle with oil at 160 and 80 in the traps.

I have the Melling HV on my new engine but I've opened up all the passages, rounded the corners and blocked the oil to the tappets and used full groove bearings I have 75/80 cold at idle and 25/30 hot. I'm using 5w20 oil though and I think I'm going to go to 0w40 or 5w30 synthetic.

Posted By: Leon441

Re: to much oil pressure? - 09/25/11 03:06 PM

Quote:

Quote:

Put in lighter oil first and see where its at... all
that pressure is just eating power

Quote:

Swap in a standard volume pump. You are just wasting power recirculating oil with that high volume pump.

I'm not buying that argument at all.

I tried a back to back run deal years ago.

Ran the car with max oil pressure and 20W-50 oil.. 100 psi.

Then drained the oil and put in 10W-30 in it. (both synthetic and same brand).. Also backed off the oil pressure with the adjustable spring. 70 psi.

The car went actually slower by .005.. And that was just due to the difference in DA..

You may see a difference on the dyno, but you wont see anything on the race track..

Just my

Chris..

Chris it is not the pressure that is killing power IMO. It is the larger gear-rotor. No matter if you bypass the oil or alow it through the engine the oil is still pumped somewhere. If you do not need the large gear-rotor of a high volume to make oil pressure go back to a stock pump. You can tighten the clearances of the stock pump too. They are sloppy.

I tried a lower releif on my engine made no differnce. Changed the pump pulley and the idle pressure was lower as well as mid range. But, at high RPM the pressure was the same. Was just no sense turning a big rotor at that speed when the engine wasn't seeing the oil. Understanding on stock pumps you can't control the gear ratio but you can change the size of the gear-rotor.

Leon

Posted By: rickstershemi

Re: to much oil pressure? - 09/25/11 03:20 PM

Quote:

Quote:

Sorry to jump in with a question: But my new 408" has what I would say unusual high oil pressure...75# - 80# at idle completely warmed up....I switched from 20/50 to 10/30 as suggested in another thread and it did lower it to 65# - 70# but still climbs to 100# as the rpms climb? It does have a Mellings HV pump and also we threw a 90* oil filter adapter on it as it was all we had lying around....it is untouched (meaning it has never had any of the neat tricks I've read about done to it to improve flow). I also run a Wix 51515R filter.

Could the 90* adapter be the problem or at least part of the problem...??????

Or am I just overly concerned...??????

Thanks in advance,

Rickster

Doubtful on the 90* filter mount... my big concern
would be possibly blowing out a filter or filter
base O-ring... I ran a stock 90* mount and never had
any where near that pressure

Having never used one I wasn't sure. I could just swap out to the standard pump I guess.....my engine builder said not to worry about it so I probably won't.....my 565" in the vette alway ran 65-70 at idle and up to 85-90 through the traps and never had an issue.

Didn't think the filter could blow out....isn't there a pressure regulator valve that keeps that from happening...???? Showing my ignorance today

Rickster

Posted By: Crizila

Re: to much oil pressure? - 09/25/11 03:36 PM

Yes, 75 - 80 is too high at idle hot. Should be in the 30 - 40 range. Go to a lighter oil - full synthetic - IMO. Highly unlikely that oil pressure is your timing chain breaking problem. Misalignment / sudden engine directional or rpm change ( backfire, etc. ) could break it.