All right boys and girls, I DID use the glorious search function, but didn't find quite the answers I was looking for. After talking with John (FourBlades) at the PCA DE this weekend about brake fluid for a track car, I thought it might be pertinent to have some of you racers weigh in on your choice of fluids. Keep in mind, the *goal* is 14 hours at Sebring. Quite likely that the first motor won't make it that long, but to give us the best chance possible, what do you think would be a good engine oil and transmission fluid to go with for a long race like that? I think 20-50 is still the go-to, but would something like Brad Penn stand up to that long of a race at temps that high? How about Swepco for the transmission? I would think both of these would call for some kind of chemistry designed for racing, but have never heard of what endurance guys use in their aircooled Porsches for long races like these.

Don't worry about the brake fluid - I think we've already decided that SRF is the only way to go.

I've heard both good & bad about the Swepco - I've used it with no problems

Oil =

Click to view attachment

Brake Fluid =

Click to view attachment

I'm a big fan of redline lightweight shock proof transmission oil
and HPS royal purple engine oil.

I don't find any problems with my brakes, despite not having vented rear calipers... I haven't had a brake problem with simple ATE super blue in 20 years of track work including enduro's. I think incorrect pads (and having them exceed their working heat range) often actually cause brake brake problems and the fluid takes the blame unnecessarily.

In my book Motul RBF600 is the best money can buy. Not sure I'd worry too much about what you run in the trans as long as it's the correct specs and is fresh. For motor oil I only have experience with Brad Penn Racing Oil 20w-50 and I would get that stuff REALLY hot and it held up well. Raby claims the new Joe Gibbs variety's are even better, so if you can stomach the price I don't think you can go wrong.

Are you running any external cooler of any sort?

He's not running an extra Cooler Yet, but I'm talking him into it

I have a Setrab that is rather beaten from an impact, but is not leaking that could be had for very cheap for the cause... If you decide to use it I'd suggest sitting down with a few beers and straighten as many fins as you can stand to do.

Thanks for the replies all. I would go with the ATE Super Blue, as I plan on going fairly easy on the brakes (a la TC's advice that most of Sebring is just brushing/dragging the brakes). But since there will be several drivers in the car other than John and myself, there is no guarantee that we will all treat the brakes the same. I like Motul as well, but not looking forward to flushing the brakes twice in a season. We plan on doing at least one DE in April before the race in September. This is why I had initially planned on the "one and done" Castrol SRF. Then again, I'm probably just being lazy. Eventually I'll need help selecting pads as well, but that's another story.

I thought the trans fluid was more of an issue, but seems that it is not. I've used Redline before, but thought any of their products would be too slippery for these boxes.

I didn't know that Brad Penn made a racing oil, but that's a good solution. I'll look into the Royal Purple too. Was just curious if BP was capable of standing up to the heat for that length of time. Regarding the cooler, as TC mentioned, he convinced me I need one somewhere. I have a Mercedes diesel cooler that would probably conform more to the Chumpcar "value-added" equation. I'd consider the Setrab if we could make it not look fancy. In order for us to be grandfathered into the $500 no-penalty category, the car has to be pretty much stock, though I think we could argue an oil cooler could almost be a safety thing - keeping blown motors and oil on the track to a minimum.

Aaron, what I'm more concerned about is how to mount one. I would ideally like to put it up front, but I've never gotten a straight answer on what else needs to be done to do so. I've been told everything from having to full-flow the case to larger volume oil pump, etc. What I have in my head - cooler up front, rubber lines down the sides, high volume pump and MOCAL sandwich adapter. Don't know if that means we'll have enough pressure in the lines to push the oil to the front and back or if it will raise the pressure in the engine to a point where it will blow seals?

I think the Ideal thing for a 1.7 is to put the Oil Cooler in the Rear above the Axles with a Fan ( there is a Thread here with pictures), that way you aren't running much line. Going to & from the front is probably 15-20 feet of line

Yeah I think we talked about that. The problem I'm concerned with then is the heat coming off the rest of the engine lowering the efficiency of the cooler, especially at speed. But you're right, that is the most realistic way to do it.

20 years ago at a DE...

I knew a guy who ran a 914
he built a small/simple bracket that bolted into the targa bar using the stock ski rack mounting point.

he installed a cooler with a simple oil filter take off adapter
he ran the lines up through the tin work and above the engine.
he pulled one of the small 5x4 engine grill covers on the chassis beside the engine lid.

and left the cooler lines long enough to bolt the cooler to his home made bracket on the targa bar.

at the end of the DE, he simply lowered the cooler back into the engine bay and had it tied securely so it didn't bounce around. the car was driven to the track and fully street legal (none of us had trailered cars back in those days)

this would be the perfect set up for a chump car
the cooler stood proud, above the targa roof into the direct air flow for maximum cooling..... yet is was small and not a huge aerodynamic drag.



oh and my opinion about the transfluid:
I've had double the number of trans failures that I have had engine failures
I honestly believe the trans fluid is VERY important these days...
I believe that the long standing reputation about 901's having high failures was earned for a reason... and I believe the reason is that they overheat when increased horsepower is applied... then failure ultimately from heat

against EVERYONES recommendation on this site, we ran mobil 1 trans fluid for 12 years on track only cars... we did it for heat.... not because it was better on porsche style syncros (it isn't) but because as a synthetic it could deal with the heat better... The bearing in the intermediate plate is usually the failure point.

Now we've switched to redline for the same reasons and I know many other 914 race cars using redline in 901's for the same reason... (just not on this site)

brant

URY used to have his Cooler in the Center of his Rear Spoiler before he Winged out on us

Hehe, those are both great ideas I had not considered before. What about the oil pump? Is stock sufficient to push the extra fluid through even a rear mounted cooler? If you choose a larger volume pump, do you run the risk of blowing out seals?

I have been told by smart people Motul better than the blue as it is easier on seals. Now that is my choice .....Buy at local motorcycle shop. Just my 2 cents.

For years I've alternated between Motul and ATE blue so I can tell easily when the fluid has completely changed color in the bleeding hoses. It might be my imagination but I seem to feel a slightly harder pedal with the Motul.

Since I've never done a blind test it's only my impression and frankly, I don't know how that would be possible, but there you go.