I need some info Penzoil 25w-50 racing

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I was looking up the specs of the Penzoil 25w-50 GT Performance Racing Motor Oil,
and I was wondering if anybody knew the HTHSV for it?

Thankyou.
 
found what might be it. but just the first paragraph.
http://www.hddeo.com/hthsarticle.html

High temperature high shear (HTHS) viscosity of engine oils is a critical property that relates to the fuel economy and durability of a running engine. The drivers behind lowering HTHS viscosity are new global governmental regulations to improve fuel economy (FE) and lower greenhouse gases (GHG) in new vehicles. Lower HTHS viscosity tends to improve FE and lower GHG but higher HTHS viscosity affords better wear protection so a careful balance must be found when formulating an engine oil. Sufficient HTHS viscosity is critical in preventing engine wear in the critical ring/liner interface area by maintaining a protective oil film between moving parts
 
Originally Posted By: Ducman
I was looking up the specs of the Penzoil 25w-50 GT Performance Racing Motor Oil,
and I was wondering if anybody knew the HTHSV for it?

Thankyou.


Do you have some? It's likely to be very high. The HTHS of Castrol Edge 25w50 is 6.
 
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Originally Posted By: supercity
Originally Posted By: Ducman
I was looking up the specs of the Penzoil 25w-50 GT Performance Racing Motor Oil,
and I was wondering if anybody knew the HTHSV for it?

Thankyou.


Do you have some? It's likely to be very high. The HTHS of Castrol Edge 25w50 is 6.




It has been used recently in an engine as the first fill/run-in oil.
Yes, as you say the HTHSV is likely to be high.

It's interesting you mention the Castrol equivalent, as it's currently under consideration/evaluation as a viable alternative going forward(and it's a little cheaper).

It could be an advantage to have the Castrol as a back-up, as supplies of the Pennzoil have proven to be a bit sketchy for us here in OZ.

The current Castrol oil, now incorporates Titanium fluid strength technology, and the specs for the original Castrol Edge Sport 25w-50(which is no longer available) are a bit different from the current Castrol Edge Titanium 25w-50.

It would be nice to have the published HTHSV for the Pennzoil, simply for a comparison to the Castrol Edge Titanium.

Thanks.
 
Originally Posted By: jrustles
This specific stuff has traditionally been made from Penn grade crude like Brad Penn, is it still that way?


I don't know.

It was originally recommended to me as an outstanding oil for this application.
It would be preferable to be able to keep using it if possible.
As posted above, the supply of the Pennzoil here in OZ is not regular, and the Castrol stuff is a little more cost effective and locally available.

Further, sadly I'm not a big fan of Castrol anyway.
 
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There is a TDS for Pennzoil GT 25W-50 on Shell's website, but it doesn't list an HTHS number. Based on its KV40 of 198, KV100 of 19.1, and its specific gravity of .89, I estimate that its HTHS would be in a range of 4.7 - 5.2.
 
Originally Posted By: A_Harman
There is a TDS for Pennzoil GT 25W-50 on Shell's website, but it doesn't list an HTHS number. Based on its KV40 of 198, KV100 of 19.1, and its specific gravity of .89, I estimate that its HTHS would be in a range of 4.7 - 5.2.


Ok.
Great, now we are really getting somewhere with this.
Obviously you are able to arrive at a HTHSV figure based on the KV number at 40 and 100 degrees C.

I have seen that TDS before.

I have the results of a VOA on the Pennzoil which was done at the local lab.
Plugging in their KV figures of 205 cSt @ 40C and 18.4 cSt @ 100C
What HTHSV do you think it would work out to be?

I am also waiting on the results of a VOA on the Castrol Edge Titanium 25w-50 to come in any day now, for a true back to back comparison of the numbers from the same lab.

Thanks.
 
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The higher KV40 and lower KV100 compared to the spec sheet only serve to lower the estimated HTHS: 5.0 maximum.

The viscosity index of your VOA is 99, which makes me think its a straight 50 weight. The VI of the GT 25W50 was 109.
 
Originally Posted By: A_Harman
The higher KV40 and lower KV100 compared to the spec sheet only serve to lower the estimated HTHS: 5.0 maximum.

The viscosity index of your VOA is 99, which makes me think its a straight 50 weight. The VI of the GT 25W50 was 109.



So the Pennzoil 25w-50 has a HTHSV of 5.0 max.
Thanks for that.

The lab states the VI to be 99 as well.
That's not in accordance with the stated VI of 109 by Pennzoil. Perhaps it's a typo on Pennzoil's part.

The Pennzoil has Zinc at 2000 PPM, Phosphorous at 1881 PPM, Molybdenum at 94 PPM and Boron at 162 PPM.
Calcium is at 2266 PPM.
TAN is 3.6 with the TBN at 8.8


The VOA for the Castrol Edge Titanium I am also looking at, has just come in this afternoon.
The numbers I am comparing are as follows.
Zinc at 1066 PPM, Phosphorous at 1003 PPM, Molybdenum at 75 PPM and Boron at 489 PPM.
Calcium is at 2238 PPM.
TAN is 2.3 with the TBN at 12.5.
The KV @ 40 C is 202 and KV @ 100 C is 20.1, and according to the lab the VI is 115.
With an advertised figure(by Castrol) of a HTHSV of 6.1?

That about covers all the relevant information that is available at this time.

Looking at the numbers as they stand, I believe the Castrol is an all round better oil(on paper) as opposed to the Pennzoil offering.
Would you consider this to be a fair assumption?
 
What is it for? That's a whole lot of Zn in the Pennzoil. Id feel more comfortable using the Edge. It should also have Titanium?
 
I'm finding it hard to believe that Castrol's 25w50 can get to 6.1 HTHS. What is its specific gravity from the spec sheet?

What engine are you going to put this oil in?
Is it roller or slider cam follower?
Does it have bearing clearances that are in the normal specified range for that engine?
Is this a racing or street engine?
What is the maximum expected oil temperature?

The Castrol oil has 880 ppm less ZDDP than the Pennzoil, but its 1000 ppm is still an effective amount, and would be OK in a roller cam engine. Also, the Titanium in the Castrol probably makes up for the lower ZDDP.

If the engine has normal bearing clearances, I don't see the need for an oil that is up to 6.1 HTHS. Is there any engine out there with "normal" bearing clearances (in the range of .001-.003") that needs more than 4.6 HTHS?

Based on the supply circumstances, I think the Castrol is probably a better choice, but I think its higher viscosity is a negative. There may be better oils for your application than either of these two.
 
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Originally Posted By: A_Harman
I'm finding it hard to believe that Castrol's 25w50 can get to 6.1 HTHS. What is its specific gravity from the spec sheet?

What engine are you going to put this oil in?
Is it roller or slider cam follower?
Does it have bearing clearances that are in the normal specified range for that engine?
Is this a racing or street engine?
What is the maximum expected oil temperature?

The Castrol oil has 880 ppm less ZDDP than the Pennzoil, but its 1000 ppm is still an effective amount, and would be OK in a roller cam engine. Also, the Titanium in the Castrol probably makes up for the lower ZDDP.

If the engine has normal bearing clearances, I don't see the need for an oil that is up to 6.1 HTHS. Is there any engine out there with "normal" bearing clearances (in the range of .001-.003") that needs more than 4.6 HTHS?

Based on the supply circumstances, I think the Castrol is probably a better choice, but I think its higher viscosity is a negative. There may be better oils for your application than either of these two.


Ok.
Thanks for the responses so far gentlemen.
To answer your queries.
I don't have the advertised figures for the specific gravity of the Castrol Edge Titanium(with the advertised HTHSV of 6.1).
All I know is that the previous incarnation of the oil was called the Edge Sport, which has an advertised HTHSV of 5.4, with a KV of 212 @ 40 C and a KV of 21 @ 100 C.
No specific gravity is advertised.

The engine is a fully blueprinted and stroked Ford 351 Cleveland(approx 390 CID with high compression) and a fairly large roller cam that makes power to about 7500 rpm, with followers that are designed to bleed oil out of the lifter gallery in order to increase the splash feed of oil to the cam lobes/roller followers.
There's a high volume oil pump that's also blueprinted, with enlarged capacity drain back holes to the sump, and reliefs/modifications all through out the entire lube circuit of the engine.

The block cooling system is grouted up to level with the bottom of the welch plug holes in order to provide reinforcement to the thin wall castings of the cylinders.
There's a large capacity oil sump with windage tray/crank scraper and baffles around the pickup.
There's a large inline full flow oil cooler mounted in front of the radiator, ahead of a positive displacement oil priming pump which incorporates the remote oil filter mount. With a larger than normal full flow oil filter that's approximately 9" long.
The total oil capacity of the entire system is approx 10 litres.

As far as oil temps are concerned, it's still undetermined at this point what the operational oil temp actually is.
However I strongly suspect the bulk oil temps are currently a little low(and well under control) in comparison to a stocker.
There is a view to keeping the bulk oil temps to a target range of about 85-90 C.

A process of gathering the relevant operational temp information for the oil and coolant is on-going at this stage.

The coolant temps are extremely well under control/stable under all circumstances(even with a standard V8 radiator).
There is currently an option of easily going hotter with the thermostat opening temp in the near future, as I feel the coolant temp is also currently a little bit low for my liking.
There's plenty of scope to tailor the cooling system to achieve any target values as required.
I fully expect this will ultimately have a degree of a flow-on effect on the bulk oil temp.

IMO, the engine is way overkill/ridiculous in the street application it's being used for, but it's just a fun machine that's intended/built to be bulletproof.
So one could easily say that it's a racing engine for use on the street.

Bearing clearances are indeed within the normal specified range.

Like yourself, I suspect there is no legitimate requirement for an oil that's quite so thick at operating temps, and that the viscosity may very well be a negative.
I also concur with you on all other observations regarding the 2 different oils.
And I am tending to lean toward the Castrol in general.
Even though I'm not really a Castrol fan as previously stated in an earlier post.

However, in order to fill in some further background information.
The person who did the machining/blueprinting work is highly regarded in our country. But he harbours a bias toward mineral oil, and he is actually strongly "anti that synthetic water [censored]" to quote his words.

When an oil recommendation was requested of him, he simply stated "a 20w-50 would be good but a 25w-50 would be better".
And so it followed, that the mineral Pennzoil 25w-50 GT Racing oil was initially chosen as the initial fill/run-in oil out of the available viscosity options. It was also recommended by him over all else.

There's only the 2 brands available to us here in OZ in 25w-50 grade, and that's the Pennzoil and Castrol offerings.
Hence my enquiry to this forum, in order to gain some more information so a better informed decision could be made going forward.

The Pennzoil is not as readily available in our locality, and is quite a bit more expensive.
On balance, looking at the figures from our local lab, the Castrol offering easily appears to be more bang for the buck. So to speak.

I have not ruled out changing to a 20w-50 grade oil sometime in the future, and the choice is wide open in that respect, whether it be a mineral oil or full synthetic(which I am partial to anyway).
Oil pressure is very good under all operating conditions.

A straight SAE 60 full synthetic motorcycle oil was under consideration at one stage, but I had rejected it out of hand quite early in the process, on the basis that it would be much too thick at operating temps with a KV of 23.4 cSt at 100 C and a HTHSV of 7.08 with the bearing clearances on this engine.

There's absolutely no lag in achieving full oil pressure when the engine is started from cold, because the engine lube circuit is completely primed by the inline external oil priming pump prior to cranking.
A generous warm up period is also applied before driving off, with a view to limiting engine revs until the engine is fully up to temp.

I intend to stay with the 25w-50 grade mineral oil for now, unless something changes with regard to the availability or formulations in the future.

With the combination of high valve spring pressures and high lift of the cam, one can hear the followers well and truly hammering away on the cam at idle even with tight valve clearances.

Given the application and operating conditions, I think it may be in my best interests to go forward with the Castrol.

Thankyou for your careful considerations on this matter so far, and it's greatly appreciated.
My apologies for the long post.
I just wanted to provide as much background info as I could.

Any further input will also be greatly appreciated in case I've missed something, or you have any further ideas.


Cheers.
 
Originally Posted By: supercity
What is it for? That's a whole lot of Zn in the Pennzoil. Id feel more comfortable using the Edge. It should also have Titanium?



Regarding the application.
Check out my last response.

I'm inclined to agree with you about preference for the Edge Titanium.

The thing is.
What's this Titanium thing all about anyway?
Looking at the limited nature of the advertised specs for the earlier incarnation(Edge Sport) and then comparing them with the equivalent advertised specs of the Edge Titanium.
They're quite different from each other since the reformulation with Titanium technology?

I wish I knew more about it all.

Thanks.
 
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The titanium is just another metal, that's reacted with some phosphorous and sulfur in the anti wear additives...more and different metals "spread" the activation temperatures across a wider range of activation temperatures.

Antimony, Tin, Zinc, Lead (Royal Purple), molybdenum, tungsten, et.al can be used to help widen that band.

I wouldn't make titanium a significant reason to go after an oil...
 
Thanks for explaining that Shannow.

With all the garbage marketing that Castrol puts out there, it's really hard for me to place any credibility on Castrol products.

They almost lost me completely with the adds in recent years of the 2 Mustangs allegedly running flat out on the dynos.
Apparently it was the car that was running the other leading brand of oil that blew it's motor up, and the one with the Castrol Edge kept on going(naturally).
If I remember correctly the last line of commentary posed the question.
Which oil do you use?

That add really made me want to go down stairs and dump the Amsoil out of my car.
And while it was draining, run down to Repco or Supercheap on foot to get the good stuff to put in.
As long as I live, I will never forget that add.

The really sad part is, there are people who see that kind of thing on TV and are influenced by it to purchase their products over anything else on the shelf.
I suppose it's a good thing they're only pedalling motor oil, and not running the country.
God knows what spin they'd be laying on us over everything that's going on.

Having said that, I currently am happily running the now superseded Castrol SAF-XA in the rear end of my car.

The Edge Titanium motor oil also generally seems to be a good thing from what I've seen on this forum.
That's one of the reasons(along with the grade of oil) why the Edge Titanium is currently under serious consideration.

On second thoughts.
Maybe they would do a pretty good job of running the country come to think of it.
Better than this lot of polies anyway. With the possible exception of Ricky Muir of course.

Back on topic.
At this stage, I am quite confident the Castrol is going to be the best option going forward. Even if the advertised HTHSV is so high at 6.1.

Many thanks to everybody for the input so far.
 
interesting motor as i used to race a 1971 Boss 351 Mustang and also a '72 Mach 1 Mustang with a '70 351 Cleveland 4v in it.

what heads and what rocker setup do you run?
i ran a trw high volumn oil pump and my mechanical autometer gauge on it showed 60-90psi nearly all the time.
what does the plastigauge show mains at?
do you run the line off the back of the blocks tap around to the main feed?

steve
 
Originally Posted By: sunruh
interesting motor as i used to race a 1971 Boss 351 Mustang and also a '72 Mach 1 Mustang with a '70 351 Cleveland 4v in it.

what heads and what rocker setup do you run?
i ran a trw high volumn oil pump and my mechanical autometer gauge on it showed 60-90psi nearly all the time.
what does the plastigauge show mains at?
do you run the line off the back of the blocks tap around to the main feed?

steve



The heads are a beautifully worked set of 4V's which have been flowed @ 709 hp @ .700" lift.
The rockers are Yella Terra platinum series rollers (standard 1.73:1 rocker ratio) with no guide plates required.
The oil pump is a Mellings select.
Bearing clearances are not verified by Plastigauge.
However Big Ends are measured to average .0026" +/- .001", Mains are measured to be between .0025" - .0028" with the exception of no 3 Main(thrust) which is .0035".
Bearing crush is between .006" - .008".
Oil pressure is virtually identical to your figures with this set up, and the 25w-50 grade oil.
Nothing exotic is being implemented in regard to supplementary plumbing for the oil circuit, as I'm not convinced anything is actually required at this point.
If anything else is necessary in regard to improvements with the block at some point in the future, this block will be retired and a Dart Windsor block will replace this cast iron unit. Everything else will be utilized in/on the Dart block.

Cheers
 
Originally Posted By: Ducman
Originally Posted By: sunruh
interesting motor as i used to race a 1971 Boss 351 Mustang and also a '72 Mach 1 Mustang with a '70 351 Cleveland 4v in it.

what heads and what rocker setup do you run?
i ran a trw high volumn oil pump and my mechanical autometer gauge on it showed 60-90psi nearly all the time.
what does the plastigauge show mains at?
do you run the line off the back of the blocks tap around to the main feed?

steve



The heads are a beautifully worked set of 4V's which have been flowed @ 709 hp @ .700" lift.
The rockers are Yella Terra platinum series rollers (standard 1.73:1 rocker ratio) with no guide plates required.
The oil pump is a Mellings select.
Bearing clearances are not verified by Plastigauge.
However Big Ends are measured to average .0026" +/- .001", Mains are measured to be between .0025" - .0028" with the exception of no 3 Main(thrust) which is .0035".
Bearing crush is between .006" - .008".
Oil pressure is virtually identical to your figures with this set up, and the 25w-50 grade oil.
Nothing exotic is being implemented in regard to supplementary plumbing for the oil circuit, as I'm not convinced anything is actually required at this point.
If anything else is necessary in regard to improvements with the block at some point in the future, this block will be retired and a Dart Windsor block will replace this cast iron unit. Everything else will be utilized in/on the Dart block.

Cheers


Just a little correction of a typo.

The tolerance on the Big Ends is +/- .0001".
I should pay more attention to counting the correct amount of zeros.
 
You are going to just have to,ignore the anti synthetic bias your engine builder has. Just because he needs theropy doesn't mean you have to follow his irrational advice.

I'd give Mobil 15w-50 a try were I in your shoes. I use it in all my vintage Small block and BB Fords. The 289's in my Shelbys have been getting it for over 15 years/150,000 miles. They are seeing numerous high speed endurance events which are over 150 miles long. The speeds are never under 120 mph and the rpm ranges from 5,000 to 7,000 for the entire run. Hot Oil pressure is a constant 78 psi (bypas set at 90 psi). Melling #10688 oil pump.

This oil and pump combinatin working very well, I have zero measurable wear on all bearings,and the Pistons as well.

Z.
 
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