9 replies to this topic

[Top Fuel F1]

1. F1: These have Dry Sump; Forced Inducted Air Cooling Radiators; and use Oil very much like the Mobile 1 Tri-synthetic 5W - 30W that I use in my own cars. I don't know much about capacity, pump types, pump rates, etc.

2. Top Fuel: These have been mostly Wet Sump; but some are moving to Dry Sump because of the new "Oil on the track" penalties. They have been using "System 1" wet sump Gear Type pumps; 22-24 gallons-per-minute; 200 psi max oil pressure at idle; 195 psi in the lights; 11 quart oil pans (in the case of wet sump); no oil radiator; an oil filter that has a filter element that can be cleaned by the supplier; a very heavy oil specially formulated for Top Fuel racing to help cushion the crank shaft. Here's some of these pumps both the wet sump and dry sump types. Once there click first on "Oil Pans, Pick-ups and Pumps" and then on "TFX" to see the pumps:

http://www.alanjohns...om/ajpframe.htm

3. IRL: Forced Inducted Air Cooling Radiators;
4. CART: Forced Inducted Air Cooling Radiators;
5. NASCAR (Grand National):
6. Le Mans Type Super Sports Cars:

[Top Fuel F1]

Pls. see:

http://speedvision.c...a1/010620b.html

[H. Eckener]

Hello Top Fuel F1,

The problem I see with the monolubrication concept besides the fact you are using an oil in the tranny that isn't optimized for the tranny is both the level of air and debris in the oil going back to the engine.
The engines bearings are much more sensitive to fine metal grit at 18,000 rpm then anything in the transmission. So by adding the transmission you have another source of potential metal grit and such that will be exposed to the engine as well.
Plus, the lubrication of the transmission with the engine oil, is bound to cause more aeration and foaming of the oil. I wonder how much of a weight savings is allowed by this monolubrication concept.

[desmo]

Last year Jag R1 had a combined lubrication system like a motorcycle, although I understand the R2 has reverted to a seperate system. Gary Anderson (in 2000 in RaceTech) on the advantages of a combined system:

"Less pumps, less weight. You get good gearbox lubrication- that is always difficult to get right. The engine by definition needs good lubrication. With engine-fed gearbox lubrication we have good gearbox oil pressure throughout the lap. Normally, gearbox lubrication, with the quantity of oil you have, is such that you only have good pressure for half the lap!

"There's no real downside. Many road cars are doing it now. The best way to save weight is to save parts by integrating the package. We have had a mysterious final drive problem and we tried running seperate oil systems in testing in view of that. But here at Silverstone we are still running the combined system, as we have been at all the races so far this year. It works very well.

"The oil tank is in the fuel tank compartment and with the bigger fuel cell we have a smaller oil tank. We had a problem where oil goes into the engine but doesnt come back out again. There might have been a similar prblem last year but last year the oil tank was big enough to have some surplus. This year we are on the borderline.

"Whenever oil disappears in the engine, there is danger of going under oil pressure thresholds and then the engine cuts out. We have got on top of that now but we don't yet know if we have fixed the underlying problem of oil getting caught up in the engine.

"Because the same oil is used for the gearbox, we didn't know at first if the oil was getting lost in the engine or the gearbox. We went through a massive programme of videoing all the oil return lines while running on the track and we got some amazing results!"

[AdamLarnachJr]

Hey TF.

I believe the 1998 NHRA rule change mandated that all Nitro cars use dry sump systems.

[Top Fuel F1]

Quote

Originally posted by AdamLarnachJr
Hey TF.

I believe the 1998 NHRA rule change mandated that all Nitro cars use dry sump systems.

I should get their rule book. However amongst all the talk about the new rules last year I never heard anyone say that was mandatory. They did mention that some cars were going to the dry sump to save them selves some money (fines in both Qual. and Eliminations) and points ( -10 points on any Oil Down beyond 3). Anyway the reason they had not been dry sump before this was that cleaning the system up after an engine break up is/was more tedious with the dry sump.

How do I get a Rulebook?
A Rulebook is included with the purchase of an NHRA membership. Individual rulebooks are
available by mailing $12 to:

NHRA Tech Department
PO Box 5555
Glendora, CA 91740-0950
Sorry, the Rulebook is not available online at this time.

Rgds;

[Top Fuel F1]

Quote

Originally posted by AdamLarnachJr
Hey TF.

I believe the 1998 NHRA rule change mandated that all Nitro cars use dry sump systems.

Adam:

I got the NHRA 2001 Rule Book today. For Top Fuel Nitro Engines it says: " Dry sump oil system permitted.". So it is not mandated at this time. Although I would hope they would have dry sump, I don't know how many are at this time. The benefits of dry sump would be in less Oil Down on the track and a much reduced exposure to a large oil fire in the event of an engine explosion.

Rgds;

[marion5drsn]

I thought we had gone thru this once before,(That is about grease in the axle/transmission)the only real reason that the transmission uses different oil (Grease) than the engine is the ring and pinion wheels are of the hyperboloid tooth pattern. These teeth slide instead of rolling against one another creating all sorts of heat problems. If the manufactures of the transmissions/axles would forget about using this type of ring and pinion wheels with “Hypoid” teeth everything would fall into place. Straight tooth bevel wheels or spiral wheels would get rid of the need for much heavier grease. This problem has been with us since about 1927 when the Gleason Gear Works designed and built for Packard a Hypoid rear axle to lower the rear axle height to make more room in the back seat of passenger cars. I can see no real reason for Hyperboloid rear axle Gear and Pinion wheels. Straight tooth bevel are somewhat noisy but spiral bevel teeth are not. This is just a case of something getting locked into a pattern and the engineers are blinded and cannot see a way out.
The spraying of oil on the backside of the teeth would give more time for the oil to cool the teeth of the bevel wheels. Anyone who has put their hand on a rear axle housing knows how hot Hypoids run, I will guarantee you that you will only do it once. Racecars do not need hypoid ring gear and pinion wheels. Who sits in the back seat of a racecar?Yours ,M.L. Anderson

[Yelnats]

marion5drsn, ... I am probably way out of date here but I was unaware that any racing designed transmission/differential would use a spiral hypoid in a gearset for exactly the reasons you have mentioned. The sound of straight cut gears were part of racing for 70 years, why would they change now?

[desmo]

And in fact I can report that modern F1 transmissions employ only straight cut gears including the bevel gears to direct the drive through the 90 degree turn required by a longitudinal transmission.