Transmission failures!

[Storm Trooper]

I am throwing this out there to see how everyone feels. Possibly a rule change?
The cost of transmissions, and repairing them has become very high.
After looking into manual transmission failures, the main contributing factor is HEAT! @ +250° The oil started to break down. The aluminum case growth is faster then the counter and main shaft. Which puts a tremendous load on the gears and synchronizer.

So I am proposing adding an external oil cooler to ours transmissions. No transmissions modification, strictly bolt on.using existing holes in the transmissions.
Something like this,

https://www.drift motion.com/Driftmotion-Manual-Transmission-Oil-Cooler-Kit-p/dm3561.htm

So thoughts? Comments?

Sean

[Fbody383]

Agree... why not? Not mandatory and useful for extending life of hard parts.

And I like being out of practice rebuilding T56s.

[Trublu]

Sean I agree heat is the main issue. I installed a cooler for Hallet and was happy with result

[Sook]

I agree with it as well. I also lost a trans at Hallett near the end of the last race, heat related IMO. I'm going to try to heat shield the exhaust pipes passing near the transmission at the very least.

- Josh

[BryanL]

Sean are you running the T 5 or T 56? Good luck getting that to pass when they won't allow you to run an aftermarket aluminum diff cover on a weak GM rearend but they will allow you to swap it out for a 9"?

[Fbody383]

Sean are you running the T 5 or T 56? Good luck getting that to pass when they won't allow you to run an aftermarket aluminum diff cover on a weak GM rearend but they will allow you to swap it out for a 9"? Tyler made the T5 go BOOM! Just ignore the fact I was driving and it was a 2-3 shift coming out of The Bitch a few weeks ago. I think it made 3 years-ish behind the LS motor...

T-56 going in for Nationals.

[BryanL]

I'm impressed and surprised the T5 lasted that long. Seems most or all of the Fords have abandoned the T5.

Are you going to submit an RCR to allow that toyota transmission? Hah.

1 minute google search came up with a t56 kit. https://www.bowlertransmissions.com/shop/manual-parts/t-56-magnum-pump-upgrade/
Then here is how to do it. http://www.pozziracing.com/Bowler%20Performance%20Transmission%20oil%20pump.h tml
But Mark Stielow says it's needed above 450 hp.

Maybe allow it for the T5 if that will keep them together-is it legal to put the T5 in a fourth gen?

Personally for the T56 I don't think it's needed. What kind of fluid are you running and how often are you changing it? Have you had it analyzed? I don't think it should break down at 250 but I'm certainly not the one to know.

[Fbody383]

What kind of fluid are you running and how often are you changing it? Have you had it analyzed? I don't think it should break down at 250 but I'm certainly not the one to know.
Purple
Change?
Never analyzed - would be a good time with the car now a project.


Late model ZO6 Corvettes and Z/28 Camaros have internal oil pumps to provide external transmission cooling. On the Z/28 the cooled oil is also run through a heat exchanger in the differential cover, then back to the transmission. When asked about T56 cooling needs, Camaro great Mark Stielow indicated a track driven T56 starts needing transmission oil cooling from around 450rwhp & up. Those driving Road Course events with high horsepower engines should incorporate transmission cooling to extend the life of their transmissions. Late model, i.e. not the stuff we run. Apples to apples we should add a cooler.

[Supercharged111]

I saw the T56 in my C5 Z06 get in the 270s on a track day so at a race like the Hallett final I wouldn't be surprised if it was north of there. I'd be willing to submit the RCR to add a cooler, but would need to figure out how to word it. Maybe jam it in here?


6.25.5 Oil and power steering coolers may be replaced or added. Coolers must be securely mounted forward of the firewall. All lines must be securely fastened and safely routed.

I think the only way to sell it is to require it be forward of the firewall, othewise it could be perceived as performance enhancing ballast.

Are you guys blowing up TKOs too or has nobody tried them? I've been kicking around the idea of one as a max effort sort of thing. The cooler is much cheaper than a TKO though and if that's all it takes to allow a lesser transmission to survive then I believe it is well in line with the intent of the series.

[Fbody383]

I think the only way to sell it is to require it be forward of the firewall, othewise it could be perceived as performance enhancing ballast. So? Cool suits are optional and there's plenty of flexibility on where to mount the cooler. Limit the trans cooler size then.

With easy ability to corner weight we keep going in circles on ballast. 1/4" plate battery box is a clear no to me. Mounting a transmission or diff cooler in the cabin using braided lines easy to get to yes.

[Pranav]

I would just add more verbage to the following to cover any ballast concerns and call it a day.

An aluminum trans cooler and some braided 6an line is not that much weight.


6.7 Ballast
Up to 150lbs of ballast is allowed, but no farther rearward than the plane of the front of the main hoop
of the roll cage. Each ballast piece may not be taller than three inches or stacked higher than three
inches. Ballast must be securely fastened and approved by NASA tech/safety officials. Battery boxes,
cool suit mounts, and other added components made excessively heavy may be determined by
NASA tech or CMC Officials to serve as ballast and therefore not allowed farther rearward than the
plane of the front of the main hoop.

Now if someone decides to take an old radiator and mount it in the trunk then yeah...

[Supercharged111]

Instead of limiting dimensions, I was thinking of limiting square inches of the cooler and then adding verbiage to include stuff like fans and mounts can't be made out of 3/8" thick steel. I'll just bounce it off the other directors and get their thoughts outside of the RCR realm.

[BryanL]

How heavy is the fluid pump going to be? Just kidding. I always think of the request by a savvy racer to add bilge blowers to cool down the brakes which wasn't allowed but now we have stoptechs. Though my car has a bilge blower for the front windshield as a defroster which might be illegal.

Make sure and get the diff cooler added as well so I can do that instead of a cover (sorry I just can't resist)

I run Motul in the trans and change it once a year. I looked it up and the flashpoint is 398 I think for whatever that is worth. Have never had any fluid analyzed other than engine oil and have no clue if it would help. Check with Craig and his gearbox business.

[Storm Trooper]

6.27.2 Transmission internals may be modified or substituted to aid in reliability, but the transmission must remain synchromesh with helical cut gears. Dog ring and straight cut gears designed to enable clutch-less shifting are not allowed.

A transmission oil cooler will aid in reliability!

[marshall_mosty]

I wonder if you could rationalize the "fill/drain plugs being substituted for a cooler system that aids in reliability"... as fitting the rules.

[Al Fernandez]

Maybe the right first step is to get temp indicators on multiple cars for national and see what the data shows.

[Supercharged111]

Maybe the right first step is to get temp indicators on multiple cars for national and see what the data shows.

Where would you draw the line for trans temps Al?

[mach1]

As far as I am concerned transmission oil coolers are legal because of 6.25.5, I would’ve put one on my car without hesitation And mounted the cooler forward of the firewall.

[WutApex]

While were on the topics of RCRs...thoughts on hood vents to evac some heat?

[Al Fernandez]

6.25 pertains to engine cooling, so 6.25.5 does not apply. Transmission modification allowances are covered in 6.27

[Al Fernandez]

Oh and I don’t know where I’d stand on what is too high but eager to hear from people smarter than me about what good looks like.

[mach1]

6.25 pertains to engine cooling, so 6.25.5 does not apply. Transmission modification allowances are covered in 6.27

A cooler trans would translate to less heat getting to the motor :-D, also since power steering is brought into the subject on 6.25 I figure the trans cooling could be argued.

In spec miata there is a concept of a "weenie protest", a protest for something that doesn't help performance, for example there were guys welding and reinforcing up the diff housings since they frequently broke, they eventually passed a rule for it but no one would really protest because it would be a "weenie protest".

A trans cooler would actually hurt performance because the cooler fluid would be more HP robbing.

[Sook]

A trans cooler would actually hurt performance because the cooler fluid would be more HP robbing.

Open up the restrictor or nitrous jet a bit more. The best part about restricted engines.

- Josh

[mach1]

Open up the restrictor or nitrous jet a bit more. The best part about restricted engines.

- Josh

Hah! What about this, go to the dyno with cold drivetrain, let the motor warm up to 180, make your 3 runs with cold trans/gear oil, done. On track the oil heats up another 75F, 3whp more in racing conditions, trans/diff cooler would help minimize the delta here. No coolers would be a bigger advantage in this example.

[Sook]

Hah! What about this, go to the dyno with cold drivetrain, let the motor warm up to 180, make your 3 runs with cold trans/gear oil, done. On track the oil heats up another 75F, 3whp more in racing conditions, trans/diff cooler would help minimize the delta here. No coolers would be a bigger advantage in this example.

DOOOODE, stop giving away the secrets!

[RichardP]

Hah! What about this, go to the dyno with cold drivetrain, let the motor warm up to 180, make your 3 runs with cold trans/gear oil, done. On track the oil heats up another 75F, 3whp more in racing conditions, trans/diff cooler would help minimize the delta here. No coolers would be a bigger advantage in this example.

To effectively do this, you have to sit in the car with the clutch pushed in while it's warming up. If it is out of gear with the clutch out, the input shaft of the transmission is spinning. If the input shaft is spinning, the cluster gear is spinning. If the cluster gear is spinning, 1st, 2nd, 3rd, and 5th are spinning. With all those gears spinning in the fluid, the fluid heats up a bit. Not as much as if you are under power, but...


Richard P.

[mach1]

DOOOODE, stop giving away the secrets!

You crazy mustang owners!!!

[Fbody383]

You crazy mustang owners!!!

Says the Musmata/Firmata guy...

[mach1]

Says the Musmata/Firmata guy...

aka, Car Guy

[Supercharged111]

You crazy mustang owners!!!

We've been saying for years they're all cheaters. . .

[liquidroam]

Where would you draw the line for trans temps Al?



I may have missed it, but I don't think the location was decided on. I think it would be a really good idea to look into this with hard data and nationals is the perfect time, unless we want to have a data collection track day between then and now.

[Al Fernandez]

I've invested $17 in a pack of temp indicators. We'll see what they tell us!