Grade of oil for drag car

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Jan 7, 2016
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Location
wellington
i currently use valvoline formula 50 25w60 in a drag car. Im looking at changing to a penrite oil as the penrite is easier to source near me

Im not very technically knowledgeable about oils. Therefore can someone please give some guidance regarding what would be a better option for my application.

The car likes to idle around 1200 to 1500rpm and my current HOT oil pressure is around high 40s to mid 50psi range depending on the day

Cold oil pressure is quite high (120psi at 2.5k rpm)

The car has ford Cleveland 383 ci with a dry sump runs on methanol has a tunnelram with dual quad carburettors and from memory runs about 0.003" main bearing clearances. I dont have the big end clearances handy. 8000rpm max. The factory ford block has had extensive oil modifications to increase oil feed to the main bearings

I use the valvoline because thats what was recommended to me years ago.

As its a drag motor with no street use at all cold oil performance isnt much of a concern. I prime the system before starting cold by spinning the pump with a drill before a cold start and run the car on lpg (propane) to warm it up which burns off most of the methanol contamination in the oil (running the dual quads it does get some methanol in the oil though)

Im going to be adding an oil preheater in the near future

Im looking at several penrite options but am not sure which would suit race motor with 003" bearing clearances and 8000rpm redline?

The valvoline specs are
racing formula 50 : mineral 25w60 viscosity 40deg 213 Viscosity 100deg 24 Viscosity index 139

All of the penrite oils im considering say theyre suitable for race fuels/methanol and are suitable for highload/race conditions.

The penrite oils im considering are

Hpr40 : mineral 25w70 Viscosity 40d 269 Viscosity 100deg 28.5 Viscosity index 140 zinc mass٪ 0.145

10 tenths racing 20 : esther synthetic 20w60 Viscosity 40d 177 Viscosity 100deg 23.7 Viscosity index 163 zinc mass٪ 0.168

10 tenths premium 10 : esther synthetic 10w60 Viscosity 40d 178 Viscosity 100deg 25.6 Viscosity index 179 zinc mass٪ 0.112

So....

Initially i was leaning towards the hpr40 its similar to the vavoline with higher hot Viscosity.

But would i be better going with one of the synthetics ? Both provide better cold Viscosity than my current mineral oil and the hpr40 mineral and the 2 hot Viscosities for the synthetics are similar or slightly better than my current oil, but a reasonable amount lower than the hpr40

With my 120ish psi cold pressure and 50ish warm idle pressure would i be better moving away from a 25w60/25w70 oil?


The costs are close enough not to be a concern... the hpr is about the same price as my current oil and the 2 synthetics are about 20/25٪ more expensive.

Thanks in advance for any advice
 
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How hard is it to pull rod caps and inspect? I’m wonder if you pull some, take some photos so as to baseline current wear, then change oil, if you can then determine at a later date which oil works for you.
 
Good advice above. If you have had the engine apart and the parts look good I would not deviate. If anything you are on the high end of viscosity. It would be good to put a silicone pad heater on your pan or oil tank. I’ll make the assumption you are NA wet sump. Methanol boils at 150F. Humidity will aggravate the situation. The heater will help keep the oil clean as well as help on the viscosity the engine sees. The valvoline race oils have a good track record. If you did want to make a change I would recommend VR1 20w50. You can also pull the oil out of the car and use a turkey frier to carefully heat the oil up and you can watch the water boil out of the oil. Don’t get it too hot or heat it too fast. Steam can make a quite impressive oil volcano. (We need not talk about personal experience here). The oil will clean up readily. If you don’t have air cleaners I would limit the oil to a dozen passes. The oil will last longer but once silicon gets above 70 ppm the dirt will contribute to wear. A oil sample could be run just so you know where the silicon level is will tell you what you need to know there.

If you have any other questions I’ll be happy to help. Also Rdy4war on this forum has a good knowledge base in drag racing as well. One of my friends in Pro Stock asked me to check him out a number of years ago. He absolutely checked out.

David
 
@dnkx if you are considering using Penrite products I’d suggest contacting them directly for recommendations. I’m not trying to discount any advice above but why not work directly with your chosen supplier?

Just my $0.02
 
What country? What brands available local to you?

20w-60

Penrite - 10 Tenths Racing series - Engine Oils

Penrite jest lepszą klasą oleju. Producent wyjątkowych olejów Penrite, płynów eksploatacyjnych, smarów oraz chemii do pielęgnacji samochodu.
www.penrite.info
www.penrite.info

Nulon also has a 5w50 and 10w60

Full Synthetic 10W-60 Racing Oil (NR10W60)


www.nulon.com.au
www.nulon.com.au
 
How hard is it to pull rod caps and inspect? I’m wonder if you pull some, take some photos so as to baseline current wear, then change oil, if you can then determine at a later date which oil works for you.
Its a fairly fresh engine. Its only had some heat up cycling in the workshop, a few burn outs and starts at a street event on it so there wont be enough wear to give any worthwhile data.

Pre rebuild the bearings were reasonable. The old build broke a rocker and a lifter popped out and caused some crank damage mid run (it was still mataining around 25psi oil pressure at the front of the block even with the lifter out)

This freshen has different crank different rods and slightly looser bearing clearances ( 003 vs 002)

Ive used the valvoline through both rebuilds.the main reason for switching is ease of sourcing where i am. Higher hot oil pressure would be nice too.
 
What country? What brands available local to you?

20w-60

Penrite - 10 Tenths Racing series - Engine Oils

Penrite jest lepszą klasą oleju. Producent wyjątkowych olejów Penrite, płynów eksploatacyjnych, smarów oraz chemii do pielęgnacji samochodu.
www.penrite.info
www.penrite.info

Nulon also has a 5w50 and 10w60

Full Synthetic 10W-60 Racing Oil (NR10W60)


www.nulon.com.au
www.nulon.com.au
Im in new zealand. We have various oil suppliers such as nulon products, pentrite, redline but is less convenient to get, and products from the likes of castrol gulf western valvoline ...

My preference toward penrite is mainly based on ease of sourcing it and they seem to have a reasonable product coverage in the ball park i think im looking at
 
Good advice above. If you have had the engine apart and the parts look good I would not deviate. If anything you are on the high end of viscosity. It would be good to put a silicone pad heater on your pan or oil tank. I’ll make the assumption you are NA wet sump. Methanol boils at 150F. Humidity will aggravate the situation. The heater will help keep the oil clean as well as help on the viscosity the engine sees. The valvoline race oils have a good track record. If you did want to make a change I would recommend VR1 20w50. You can also pull the oil out of the car and use a turkey frier to carefully heat the oil up and you can watch the water boil out of the oil. Don’t get it too hot or heat it too fast. Steam can make a quite impressive oil volcano. (We need not talk about personal experience here). The oil will clean up readily. If you don’t have air cleaners I would limit the oil to a dozen passes. The oil will last longer but once silicon gets above 70 ppm the dirt will contribute to wear. A oil sample could be run just so you know where the silicon level is will tell you what you need to know there.

If you have any other questions I’ll be happy to help. Also Rdy4war on this forum has a good knowledge base in drag racing as well. One of my friends in Pro Stock asked me to check him out a number of years ago. He absolutely checked out.

David

Im in new zealand so shipping small quantities of dangerous goods like oil is a nightmare. Even mail ordering a k n air filyer pre oiled is a headache.. but if your able to give some guidance regarding which way to go with the on paper specifications it would be appreciated

This is a dry sump.. ive played with boiling the oil out of the car before.. in all honesty running it up to operating temp on lpg (propane) does a very good job of keeping the methanol contamination under control.. but it sometimes gets overly hot with that method.

With your comment re my viscosity being on the upper end.. are you thinking one of the synthetics might work out better than the 25w70?

I like the idea of the 25w70 as it will presumably give better hot oil pressure... but im wondering if the oil would also get hotter just from being pumped... which would make the oil less effective as it would be thinner from the extra heat...

Would i be likely to gain any oil pressure from the synthetics being slippryier and lower viscosity?. Ie Doing a controlled pre heat with a heater and the thinner oil heating up less from being pumped would this be likely to give me higher hot.pressure from a less heat stressed oil?
 
What is your oil pressure going down the track. You mentioned cold pressure and Idle when hot but pressure down the track is what
Down the track its on about 65 to 70.. on a hot day it has come down to as low as 60. (Hot days here are 30geg c (85deg f) ) i recently fitted an oil cooler to the pressure side after the filter but haven't had it on the track since fitting the cooler (cooler is only about 8x8" and two core thickness )
 
Down the track its on about 65 to 70.. on a hot day it has come down to as low as 60. (Hot days here are 30geg c (85deg f) ) i recently fitted an oil cooler to the pressure side after the filter but haven't had it on the track since fitting the cooler (cooler is only about 8x8" and two core thickness )
Check out Gulf Western Comp R oils and give them a call. They are all available in NZ. My tuner uses this oil with 1000hp Barras etc at the strip.
 
As stated, I probably wouldn't change things if it's working for you. That includes the oil cooler. In drag racing, we want to get the oil hot to keep down fuel and water dilution (especially with methanol) and drive additive reactivity.

If made any change, I would pick Penrite 10 Tenths Racing 20W-60 or even 15W-50.
 
Ford Cleveland’s like high oil pressure. With.003” clearance on both rods and mains, you need the high viscosity. SAE 50 is another option, you want at least 5.0 hths in my opinion.
 
Reher Morrison Racing Engines recommends 10w-30 in cool weather and 20w-50 in hot weather. Here their tech article on the subject:


I always ran conventional 15w-40 in my 1100+ hp normally aspirated gasoline BBC drag race engines
 
David Reher is a very knowledgeable person. His history in Pro Stock and always being close with Richard Maskin places him in a very small living legend category in Drag Racing he is one of the few people I work with that know enough to make good product decisions together. David is very results driven and very slow and methodical about making changes. This oil is for his Nitrous program. Even at 10w50 it’s good for several thousand horsepower.

53860624-CCFB-4C44-AD94-67FEDCE74ECB.jpeg
 
loving the inside info on oils + lubrication as theres always MORE to learn!!
 
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