Road race oil

[dailydriver]

Originally Posted By: A_Harman
Originally Posted By: CATERHAM
Originally Posted By: A_Harman
Originally Posted By: CATERHAM
A_H, how much higher is the OP in your Z28 with the RL 5W-30 vs the 5W-30 M1 you used to run?

I saw about a 5psi increase in oil pressure at hot idle with the RL.

Thanks, so what is the actual hot OP in psi at idle and at high rev's with the RL vs M1?


Out on the track with the engine running about 235F coolant temperature, the M1 ran about 40 psi at the end of long straights at ~5000rpm. Under similar conditions, RL runs about 45 psi. My numbers are approximate because the pressure gauge only has markings of 20, 40, 60, and 80 psi. I used to fret about why my track cars have a hard time topping 40 psi oil pressure, but after years of seeing them survive, I've gotten more comfortable with it.


Is this the stock, in the cluster gauge, or an aftermarket unit?

 

[A_Harman]

It's the stock gauge cluster.

 

[CATERHAM]

Originally Posted By: A_Harman
Originally Posted By: CATERHAM
Originally Posted By: A_Harman
Originally Posted By: CATERHAM
A_H, how much higher is the OP in your Z28 with the RL 5W-30 vs the 5W-30 M1 you used to run?

I saw about a 5psi increase in oil pressure at hot idle with the RL.

Thanks, so what is the actual hot OP in psi at idle and at high rev's with the RL vs M1?

Out on the track with the engine running about 235F coolant temperature, the M1 ran about 40 psi at the end of long straights at ~5000rpm. Under similar conditions, RL runs about 45 psi. My numbers are approximate because the pressure gauge only has markings of 20, 40, 60, and 80 psi. I used to fret about why my track cars have a hard time topping 40 psi oil pressure, but after years of seeing them survive, I've gotten more comfortable with it.

Thanks A_H.
-Do you have any idea what the oil temp's would be when the OP dropped into the low 40 psi range?
-Does the OP in your Chevy continue to rise past 5,000 rpm or has it max'd out?
-On the street what does the OP generally settle at @5,000 rpm?

Sorry for the on going questions but you've piqued my interest.

 

[A_Harman]

My instrument cluster does not have an oil temperature gauge, so I'm running blind on oil temperature. The oil pressure while running on the track is pretty much constant from 4000 rpm. If I'm just driving around on the street with the engine at normal operating temperature (around 210F), and do a single 5000 rpm blast, the oil pressure will go to about 70 psi. I don't remember ever seeing the oil pressure gauge get to 80 psi.

 

[Promo]

You run into the same problem that I do, but since you've been doing it much longer than I have and haven't had any issues.. I'm not sure if it's considered a problem anymore.
The OP drops after 15 mins of tracking. Mine's at 60-65psi from 4k to redline when it hits that point. I've never seen it go lower than 60 but i'm sure it would if I was out there for more than 20 minutes at a time.

 

[CATERHAM]

Originally Posted By: A_Harman
My instrument cluster does not have an oil temperature gauge, so I'm running blind on oil temperature. The oil pressure while running on the track is pretty much constant from 4000 rpm. If I'm just driving around on the street with the engine at normal operating temperature (around 210F), and do a single 5000 rpm blast, the oil pressure will go to about 70 psi. I don't remember ever seeing the oil pressure gauge get to 80 psi.

Then one could safely conclude that your oil pump by-pass level is 70 psi which sounds about right for a Chevy.
Assuming 70 psi corresponds with an oil temp' in the 90-100C range your track oil temp's are indeed getting very high to thin the oil out enough to drop the OP down into the 40C range.

 

[CATERHAM]

Originally Posted By: Promo
OP drops after 15 mins of tracking. Mine's at 60-65psi from 4k to redline when it hits that point. I've never seen it go lower than 60 but i'm sure it would if I was out there for more than 20 minutes at a time.

Not necessarily.
In my cool running Caterham (has a massive finned aluminum sump in the air flow), max' oil temp's on the street (with a shrouded sump) are in the 80-85C range. On the track with an unshrouded sump (for maximum cooling effect), the oil temp's stabilizes at 95C and rarely climbs higher than that even if I'm on the track for an hour at a stretch.
BTW, that's the reason why I can get away with running a light (2.6 HTHSV) 20wt oil on the track and still maintain a minimum 65-70 psi OP; my oil temp's are well contained.

 

[Promo]

How much is a Caterham? I've thought about getting one. They're cheap(ish) for what they can do.

 

[CATERHAM]

Caterhams start at about $40,000 and progress up to about $80,000.
My fav' model is the "weapons grade" R500 Superlight that is about $68,000. It has 263 hp and weights about 1,100 lbs.
As a track day car nothing can touch it.

http://www.uscaterham.com/showroom/R500.html

 

[SteveSRT8]

While I love the caterham I am a big fan of this car:

http://en.wikipedia.org/wiki/Ariel_Atom

as I spent a day at the track where one was. What a thrill ride!

 

[CATERHAM]

I've driven an Atom on the track, (a 230 hp version) and it's a great track car.
It's a different flavor of the much the same thing as the Caterham 7.

I prefer the Caterham for it's looks and 55 year heritage, (an continuation of the 1957 Lotus 7). It's also about 200 lbs lighter and it's handling has been sorted to perfection while (and most would agree) the Atom's handling doesn't give the same level of confidence when driven at the limit; everyone comes away thinking it needs this or it needs that.
Additionally the Caterham 7 is more practical as a road car since most models come with a windsheild, electric wipers, a heater and convertible top which my car has all of.

But the Ariel Atom is indeed another very unique and fast British track day weapon.

 

[SteveSRT8]

Funny the Atom is claimed to weigh 1010 pounds.

Either way, I agree, they are two different flavors of great ice cream.