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any advantage to higher oil pressure? by AL87
Started on: 07-07-2014 11:58 PM
Replies: 16 (418 views)
Last post by: TT Slick on 07-14-2014 08:07 PM
AL87
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Report this Post07-07-2014 11:58 PM Click Here to See the Profile for AL87Click Here to Email AL87Send a Private Message to AL87Edit/Delete MessageReply w/QuoteDirect Link to This Post
http://www.ebay.com/itm/191...id=p3984.m1423.l2649

the 2.8 has some things in common with the sbc, I was wondering if this would work...

also wondering of any particular advantage as well.
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Report this Post07-08-2014 09:29 AM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
Better oil flow is advantageous. Pressure would be the measure of resistance to flow.
Usually when people want better flow in any engine they use a higher volume oil pump and or ream out any obstructions in the flow path.
You can also gain by using a good synthetic oil that is only as "thick" as needed.

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Kevin87FieroGT
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Report this Post07-08-2014 09:36 AM Click Here to See the Profile for Kevin87FieroGTSend a Private Message to Kevin87FieroGTEdit/Delete MessageReply w/QuoteDirect Link to This Post
Guess you would have to buy a new Summit pump for this to work.

Notes
65-70 psi. Designed for Summit high performance race pumps only.
Oil Pump Spring Material
Steel
Quantity
Sold individually.
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fierofool
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Report this Post07-08-2014 01:31 PM Click Here to See the Profile for fierofoolClick Here to visit fierofool's HomePageClick Here to Email fierofoolSend a Private Message to fierofoolEdit/Delete MessageReply w/QuoteDirect Link to This Post
Excessive oil pressure can blow seals, especially the rear main seal. Decades ago, NASCAR had problems with the cars blowing engines in the early laps. They found that it was due to not warming the engine up well enough and the high oil pressure was blowing the seals, causing bearing failure. That was in the days when single weight oils were more common. It's also part of the reason for the warmup laps.

You could upgrade to the 3.4 oil pump which is a little higher volume pump, but if you're using the 2.8 oil pan, you'll have to notch out the baffle to clear the pickup.

[This message has been edited by fierofool (edited 07-08-2014).]

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TT Slick
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Report this Post07-08-2014 01:54 PM Click Here to See the Profile for TT SlickClick Here to Email TT SlickSend a Private Message to TT SlickEdit/Delete MessageReply w/QuoteDirect Link to This Post
We used to think more is better, but 10psi/per 1000 rpm is all thats needed. A high volume high pressure pump on 10-30 oil requires 5 hp to drive, and more load on the cam gear and distributor gear.

Just my 2 cents.
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Lou6t4gto
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Report this Post07-10-2014 01:58 PM Click Here to See the Profile for Lou6t4gtoClick Here to Email Lou6t4gtoSend a Private Message to Lou6t4gtoEdit/Delete MessageReply w/QuoteDirect Link to This Post
what you said just summed it up. That's what Smokey Yunik said "10 lbs per 1000 RPMs". BUT, my 2.5 has 30 psi at Idle Cold, and after it's at 180 it's 20 and only 25 at 3000 RPMs ! The engine only has 3-4k miles on it. (Stock Oil pump). Is there a HV or HP PUMP "available" for a 2.5 ?? Or a high pressure relief SPRING for it ?
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Report this Post07-10-2014 02:15 PM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Lou6t4gto:

what you said just summed it up. That's what Smokey Yunik said "10 lbs per 1000 RPMs". BUT, my 2.5 has 30 psi at Idle Cold, and after it's at 180 it's 20 and only 25 at 3000 RPMs ! The engine only has 3-4k miles on it. (Stock Oil pump). Is there a HV or HP PUMP "available" for a 2.5 ?? Or a high pressure relief SPRING for it ?


Is that with an external gauge or the stock one?
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KurtAKX
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Report this Post07-10-2014 03:09 PM Click Here to See the Profile for KurtAKXSend a Private Message to KurtAKXEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Lou6t4gto:

what you said just summed it up. That's what Smokey Yunik said "10 lbs per 1000 RPMs". BUT, my 2.5 has 30 psi at Idle Cold, and after it's at 180 it's 20 and only 25 at 3000 RPMs ! The engine only has 3-4k miles on it. (Stock Oil pump). Is there a HV or HP PUMP "available" for a 2.5 ?? Or a high pressure relief SPRING for it ?


You don't need a HV pump for the 2.5. In fact, when you put a high volume pump on, you risk shearing the pin that holds the oil pump drive gear to the oil pump driveshaft.
If you use the correct weight oil, you'll get sufficient flow and won't need a higher pressure relief spring.

If you feel desperate to have a higher relief pressure at the pump, then you can knock out the roll pin and shim the existing spring with a couple of small washers. Do not over-do it.

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FTF Engineering
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Report this Post07-10-2014 10:27 PM Click Here to See the Profile for FTF EngineeringSend a Private Message to FTF EngineeringEdit/Delete MessageReply w/QuoteDirect Link to This Post
A higher pressure relief spring isn't going to fix anyone's low oil pressure issues.

The only thing that spring does is limits the upper end of what pressure the pump will be able to build if the conditions are right. But once the oil is warm and the RPMs are down, the pump simply isn't able to build anywhere near the limit pressure, so that spring isn't a factor.

Don't think of the spring as a regulator. Think of it as an upper limit safety blow off valve instead.
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Lou6t4gto
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Report this Post07-11-2014 03:08 AM Click Here to See the Profile for Lou6t4gtoClick Here to Email Lou6t4gtoSend a Private Message to Lou6t4gtoEdit/Delete MessageReply w/QuoteDirect Link to This Post
My point being, only 3-4k miles, new crank, bearings etc , but "10 PSI per 1000 rpms," and this is 25 at 4K RPMs, should be 40 PSI.. Still has the original oil pump. I know it's not going to blow up, it never gets driven hard. just wondering.
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Report this Post07-11-2014 08:27 AM Click Here to See the Profile for CsjagClick Here to Email CsjagSend a Private Message to CsjagEdit/Delete MessageReply w/QuoteDirect Link to This Post
On my 2.5 the oil pressure is 30psi at idle and at 60 mph cruising speed is 45ps in fifth gear. I am running 10w-30 dino oil. Should I switch to a lighter weight oil? The car has 118k miles on it and has never had synthetic in it so I don't want to put any in at this point. Thanks
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Report this Post07-11-2014 08:35 AM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Csjag:

On my 2.5 the oil pressure is 30psi at idle and at 60 mph cruising speed is 45ps in fifth gear. I am running 10w-30 dino oil. Should I switch to a lighter weight oil? The car has 118k miles on it and has never had synthetic in it so I don't want to put any in at this point. Thanks


If those are at warm temps (after driving about 20-30 mins and your temp is around 190) you definitley could, 5w30 is factory recommended.

[This message has been edited by 2.5 (edited 07-11-2014).]

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TT Slick
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Report this Post07-11-2014 08:46 AM Click Here to See the Profile for TT SlickClick Here to Email TT SlickSend a Private Message to TT SlickEdit/Delete MessageReply w/QuoteDirect Link to This Post
From what I've seen most if not all GM pumps were made from cast aluminum which wear out very quickly on the inside, a good replacement pump (Melling) will be cast iron. I think you should have put in a new pump.
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Report this Post07-11-2014 10:19 AM Click Here to See the Profile for TONY_CSend a Private Message to TONY_CEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Lou6t4gto:

My point being, only 3-4k miles, new crank, bearings etc , but "10 PSI per 1000 rpms," and this is 25 at 4K RPMs, should be 40 PSI.. Still has the original oil pump. I know it's not going to blow up, it never gets driven hard. just wondering.


When you had the engine apart did you check the oil pump clearances to see if everything was in spec?
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KurtAKX
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Report this Post07-14-2014 04:04 PM Click Here to See the Profile for KurtAKXSend a Private Message to KurtAKXEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by TT Slick:

From what I've seen most if not all GM pumps were made from cast aluminum which wear out very quickly on the inside, a good replacement pump (Melling) will be cast iron. I think you should have put in a new pump.


Have you disassembled a 2.5 before? I have never seen an aluminum 2.5 oil pump.
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Report this Post07-14-2014 04:06 PM Click Here to See the Profile for KurtAKXSend a Private Message to KurtAKXEdit/Delete MessageReply w/QuoteDirect Link to This Post

KurtAKX

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quote
Originally posted by FTF Engineering:

A higher pressure relief spring isn't going to fix anyone's low oil pressure issues.

The only thing that spring does is limits the upper end of what pressure the pump will be able to build if the conditions are right. But once the oil is warm and the RPMs are down, the pump simply isn't able to build anywhere near the limit pressure, so that spring isn't a factor.

Don't think of the spring as a regulator. Think of it as an upper limit safety blow off valve instead.


^ What he said.
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TT Slick
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Report this Post07-14-2014 08:07 PM Click Here to See the Profile for TT SlickClick Here to Email TT SlickSend a Private Message to TT SlickEdit/Delete MessageReply w/QuoteDirect Link to This Post
No, I have only been in 2.8 and 3.1.
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