Built autoX 1967 Sprite, what oils?

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SOHCman

SOHCman

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A buddy is looking at getting into auto cross with a 67 sprite, owner says he has ran Dino castrol 20w-50. What would be recommended for a built 1200 something cc pushrod engine that revs out to 9k? It does have oil cooling, uses 105 BP red (oh that smell...), electric water pump but no fan. I am sure a OC every event is good for longevity.

The 4 speed and diff were ran with Dino as well, but unsure on type. Rear end has a Detroit locker/ limited slip.

Thanks, any tips on vintage racing are appreciated.
 
Ok, so keep the 20w-50, but what kind? Harley davidson makes a fairly stout Dino, are there any heavier diesel oils that would work well?

Pretty sweet engine, carbon fiber pushrods, titanium valve train parts, very trick.
 
No kidding? I would have thought 90 weight gear oil, which is the same viscosity range as a 50 motor oil of corse.
 
I'm a big fan of rotellas oils, a 20w50 would probably be the ticket eh?
 
What about using M1 15w-50 in this engine? It is a group 3 syn now I believe.
 
Originally Posted By: EddieCairns
The gearbox takes the same oil as the engine.

Either the Castrol 20W/50 Dino
or Mobil 1 0w40 or 10W/50


I am fairly certain this is a factory trans, the previous owner used 80w-90 gear oil. Do you have a link specifying 20w-50 for the trans? Thanks!
 
Originally Posted By: expat
What oil temps is he seeing?

Many 'Hot' Brit engines are running 15w40


I am not positive of the temps, presumably quite hot. It is capable of 9-10k rpm, has an electric water pump but no radiator fan. Big alum radiator with an oil cooler behind it.
 
That must be quite some engine to reach 9-10 K rpm with pushrods. . . .

Doubt the car requires an oil change after every event. Typically an SCCA Solo event would involve driving for only 4 to 8 minutes total over maybe 4 runs per day. I autocross my Alfa maybe 10 times per year and just change the oil yearly. It only has about 2000 miles on it per year, and very few of those are autocross miles.

I agree with another poster that a 15w40 HDEO might be a good fit for this car.
 
Originally Posted By: SOHCman
Originally Posted By: expat
What oil temps is he seeing?

Many 'Hot' Brit engines are running 15w40


I am not positive of the temps, presumably quite hot. It is capable of 9-10k rpm, has an electric water pump but no radiator fan. Big alum radiator with an oil cooler behind it.

AutoX doesn't generate high oil temp's in fact the temp's are usually well below normal.
This is obviously a vary trick custom engine.
I'd want to know the oil pressure levels and by-pass point.
I can't imagine that a heavy oil makes much sense.
I'd be thinking of something like Red Line 0W-40 with the final viscosity choice based on OP and OT. I doubt this oil would be too light, but if so fine tune with some RL 10W-60.
If the RL 0W-40 is still too heavy which is possible if max' oil temp's are not high, then thin the oil out with some RL 0W-20.
 
Originally Posted By: SOHCman
Originally Posted By: expat
What oil temps is he seeing?

Many 'Hot' Brit engines are running 15w40


I am not positive of the temps, presumably quite hot. It is capable of 9-10k rpm, has an electric water pump but no radiator fan. Big alum radiator with an oil cooler behind it.


Hummm....I have run slaloms with my Spitfire. It's difficult to drive the car at an event just to warm the engine, so I end up running the engine while stationary to get up to operating temps.
The oil temp is much slower to rise that the coolant, so I end up with the electric cooling fan running (to prevent a boil-up) while the oil temp (even without an oil cooler*) gets to a reasonable operating level (175 F) before I run.

I agree, getting the oil too hot, on a short slalom course, doesn't seem to be an issue.

*I now use a Coolant to Oil heat exchanger
 
Yes installing a coolant/oil heat exchanger is ideal for any engine that doesn't have one.

I considered installing one on my Caterham (some owners in the UK have) but it's not easy and is expensive to do it right.
Instead I run a 0W-20 with a shroud under the sump to retain as much heat as possible for street use. For high speed track use the shroud is easily removable for maximum air flow over the heavily finned ali' sump.
 
Originally Posted By: CATERHAM
Yes installing a coolant/oil heat exchanger is ideal for any engine that doesn't have one.

I considered installing one on my Caterham (some owners in the UK have) but it's not easy and is expensive to do it right.
Instead I run a 0W-20 with a shroud under the sump to retain as much heat as possible for street use. For high speed track use the shroud is easily removable for maximum air flow over the heavily finned ali' sump.


What engine?
 
Originally Posted By: CATERHAM
A Caterham modified 2L 16V Vauxhall/Cosworth C20XE 190 hp



thumbsup2.gif


Glad to hear you have a 'real' car engine in there.
7's with Bike engines arn't my thing.

Do you know David Saville-Peck?
 
Thanks for the advise,

I will find out what oil temps it sees, what would be a good threshold for staying with 50wt? 250F? As in if it stays below, move to a 15w40 hdeo?

It may be worth running a pan heat pad before the run to encourage the oil to reach operating temp perhaps?
 
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