Diff Coolers

[StephenB]

What are you thoughts about allowing Rear End Diff Coolers into IT? To far of a stretch based on the philosphy of IT? If I do run one can I disconnect it when running IT events or would that still be considered a no no just having it part of the car.

Interested in what you think...

Stephen

[Gary L]

Required reading:

http://www.improvedtouring.com/forums/showthread.php?t=26985

Just for the record, I'm in the "no more coolers" camp.

As for running a disconnected diff cooler in IT - show me the ITCS paragraph that says you can mount a non-functional diff cooler. IMO, this would clearly fall under IIDSYCTYC. For that matter, the cooler could also be considered illegal ballast... unless of course, you mount it in the passenger footwell. :D

[joeg]

Beyond a stretch.

Better to solve the problem with chemistry--if it is a big problem. You can treat and coat your R&P with the latest high-tech magic dust and be legal; final drives being free in IT.

Good lubricant--changed frequently--helps also.

[jlucas]

I think they should be allowed just like oil coolers, and non-stock radiators.

Also they are allowed in Touring, so cars aging out into IT would potentially already have them.

[dickita15]

Actually in Touring I believe while transmission coolers are allowed differential coolers are only allowed on a case by case basis. Of course in Touring they do not have the options of touching the internals as we do.

[Andy Bettencourt]

I love the idea of diff coolers. We allow internal components to be uprated, allow us to keep them cool.

[MMiskoe]

If you showed up at impound w/ the cooler there, but disconnected I would commend you for being honest and go on to worry about other things.

I can see the advantage on very few occasions during a sprint race. Longer races, yes, I can see you wanting to keep the oil cool rather than buying new guts for the diff.

If the R&P and LSD system you are using comes standard w/ an oil cooler I would consider arguing it. "Any final drive...." "Any limited slip..." provided they fit w/in the stock housing w/o modification. That is where you will have problems, getting the oil in & out w/o drilling holes in something. But if the "Gnicar TSR" brand ring & pinion comes standard with an oil cooler, well its part of the system. Isn't it? How is that different than the aftermarket ECU that utilizes a MAP sensor that gets tapped into an otherwise blank hole in the manifold? There is an allowance for the MAP sensor now, similar to spherical bearings that after a few years of people using the loophole the ITCS was altered to allow it.

Considering I got my log book written up for a carpet hanger being missing where it doesn't say I can remove it, I say this is no more of a stretch in the other direction.

[StephenB]

I am thinking of doing some enduros and running ITE since the Diff is not legal. As others said my diff is 2k and I don't want to throw it away when I could easily just run in ITE. I am just conserned that when I run the PRO-IT stuff or NARRC stuff in ITR that I may get protested even if it is disconnected, as someone above mentioned they would.

I will hold off on installing it for now. I am installing a temp gauge and I will check that out for my sprint races and then make some more decisions later. I bet I can fab something up that can have the entire cooler completely removed from the car when needed.

Stephen

On a side note... what is the reason some of the touring cars are allowed to add one? (other than obvious cooling) Does it actually provide a competitive advatage other than reliability?

[Knestis]

...if the "Gnicar TSR" brand ring & pinion comes standard with an oil cooler, well its part of the system. Isn't it? How is that different than the aftermarket ECU that utilizes a MAP sensor that gets tapped into an otherwise blank hole in the manifold? There is an allowance for the MAP sensor now, similar to spherical bearings that after a few years of people using the loophole the ITCS was altered to allow it.

Considering I got my log book written up for a carpet hanger being missing where it doesn't say I can remove it, I say this is no more of a stretch in the other direction.

...and if the Blowmeister air filter and intake comes with a turbo...? Jeez, guys.

And I was thinking to myself when I opened this today, how I really haven't been given reason to worry recently.

:blink:

K

EDIT - this is not to say that I think gearbox coolers are necessarily inconsistent with other current allowances.

[Ron Earp]

Considering I got my log book written up for a carpet hanger being missing where it doesn't say I can remove it, I say this is no more of a stretch in the other direction.

Really? Wow. Protest or a tech inspector doing a lot more than tech?

[seckerich]

Diff coolers would be OK if they were limited to 5 psi or less circulating pumps. Anything else opens big can of worms that Kirk sees. :023:

The rear gears on the GA RX8's would die very quickly before we went to the diff and trans coolers with low pressure circulating pumps. One ITR guy changes out to run SCCA sprints but will not run the longer races at $2500 per weekend for gears. No cover mods needed, just in the fill and out the drain plug.

[MMiskoe]

...and if the Blowmeister air filter and intake comes with a turbo...? Jeez, guys.I didn't say it was a slam dunk, but I do feel it falls in the category of the MAP sensor (before the rule change) or accumulator tanks for fuel cells. These are things that clearly reach past where they were originally thought to go and are based on the allowance that includes the word "any".



Really? Wow. Protest or a tech inspector doing a lot more than tech? Yup. There is a note in the log book to have it corrected by next event. The sheetmetal that covers the fuel lines in the back of a Miata to be exact. I offered to come back w/ a paddock wide protest on tire pressures, alignment settings, spacing of class letters/numbers and washer bottles but was told not to. The whole affair didn't do much to endear me to tech.

[JeffYoung]

We seem to have gotten by for a long time without these. Maybe I'm getting old and crotchety, but I don't see the need for the allowance.

[Matt93SE]

Yup. There is a note in the log book to have it corrected by next event. The sheetmetal that covers the fuel lines in the back of a Miata to be exact.

That's big difference from a carpet hold-down clip, which is specifically allowed to be removed.. The rules state that there must be a metal shield/bulkhead between the driver compartment and the gas tank or any hose/tube that carries combustible liquid- i.e. oil or fuel lines. and/or those lines must be metal or metal braided.

This is a safety thing for all classes, not a you-can't-remove-that-in-IT thing.

In come classes (like STU), it's mentioned right there in the rules. it's also listed in the regular ruleset under 9.3.(28?) specifically regarding fuel cells, but the same rules apply to the factory tank too. can't remember exactly where it says it, but it's in there.

[lateapex911]

That's big difference from a carpet hold-down clip, which is specifically allowed to be removed.. The rules state that there must be a metal shield/bulkhead between the driver compartment and the gas tank or any hose/tube that carries combustible liquid- i.e. oil or fuel lines. and/or those lines must be metal or metal braided.

This is a safety thing for all classes, not a you-can't-remove-that-in-IT thing.

In come classes (like STU), it's mentioned right there in the rules. it's also listed in the regular ruleset under 9.3.(28?) specifically regarding fuel cells, but the same rules apply to the factory tank too. can't remember exactly where it says it, but it's in there.

I thought that too when i read the post. But, thinking further, I bet those lines are metal. If they ARE rubber, then yea, that's a problem.

[Chip42]

I remember one of the first 6 hour races at summit point(which became the 12 hours) a bunch of 2nd gen RX7s were having diff overheating issues - most teams wound up replacing gear oil every couple of hours in the pits, some keeping their new oil on ice.

the next year I saw none of this. RX7s have only goten faster.

I don't know what the fix was, but the evidence was that it worked. I can't imagine a similar logic wouldn't apply in most cases. it might not be the optimal differential under the current paradigm, but a solution is out there, even if it's a compromise. what's that old saying, "in order to finish first, you must first finish?"

that said, I don't think coolers are outside of the philosophy, necessarily, only that I don't think their need is a foregone conclusion.

[Matt93SE]

I thought that too when i read the post. But, thinking further, I bet those lines are metal. If they ARE rubber, then yea, that's a problem.

I'm assuming the cover he's referring to is the one that covers the fuel pump and the rubber lines that attach the pump/sending unit to the factory hard lines. there's a ~6" section of rubber line there on send and return lines.

http://boostedmiata.com/FAQ/fuel_install/step1.jpg
http://boostedmiata.com/FAQ/fuel_install/step2.jpg

If I saw a car roll through tech without that panel, I'd sure as heck put that in the logbook to fix.

[Andy Bettencourt]

We seem to have gotten by for a long time without these. Maybe I'm getting old and crotchety, but I don't see the need for the allowance.

You could say that about any change you make.

[Chip42]

You could say that about any change you make.

if we add open fluid coolers, I want the evap system and power steering to be allowed for removal to facilitate their instalation.

[Matt93SE]

Secondededed. I installed an aftermarket power steering cooler on my car. The entire power steering system died after the next 1/2 lap on track. So if they're going let you to add coolers, I should be able to remove the whole system so I can simply remove the source of heat.

;)

[StephenB]

Diff coolers would be OK if they were limited to 5 psi or less circulating pumps. Anything else opens big can of worms that Kirk sees. :023:

The rear gears on the GA RX8's would die very quickly before we went to the diff and trans coolers with low pressure circulating pumps. One ITR guy changes out to run SCCA sprints but will not run the longer races at $2500 per weekend for gears. No cover mods needed, just in the fill and out the drain plug.

Steve,

This is for my RX8 with a Grand-AM rear end. Do you happen to know the temperature that is acceptable before they do die? How long before you guys started seeing failures? Was it length of time on track per session, or time on track total? Did changing the diff oil more frequently help... is it needed every session, weeknd, or season? Do you have any suggestions on the best Diff fluid that I should use?

Stephen

PS: I TOTALLY agree that the allowance of a diff coller would allow me to have a competitive advantage over others simply by allowing me to run this rear end safely without the gamble I am going to take. This is why I asked if it was within what others thought was the philosophy of the class. We are allowed to do anything to the rear end which is within the philosophy of the class, this allowance just makes those modifications we are allowed to do more reliable.

Thanks for everyones opinions.

[JoshS]

We are allowed to do anything to the rear end which is within the philosophy of the class, this allowance just makes those modifications we are allowed to do more reliable.

Who said you "are allowed to do anything to the rear end?" That's not true. 9.1.3.D.4 lists the only modifications that can be made to the final drive. If you could do "anything", it would say so. But it doesn't. It says that you can change the final drive ratio, and that you can replace the differential. You can't do anything else, it's that simple.

The philosophy of the class is limited modifications, and moreso, only limited modifications, only those listed. It is NOT the philosophy of the class to find unlisted modifications that are somehow similar to those listed, and claim that those are (or ought to be) legal too.

[Andy Bettencourt]

if we add open fluid coolers, I want the evap system and power steering to be allowed for removal to facilitate their instalation.

HA! Oil coolers and radiators are almost free now so that's moot.

[Andy Bettencourt]

Who said you "are allowed to do anything to the rear end?" That's not true. 9.1.3.D.4 lists the only modifications that can be made to the final drive. If you could do "anything", it would say so. But it doesn't. It says that you can change the final drive ratio, and that you can replace the differential. You can't do anything else, it's that simple.

The philosophy of the class is limited modifications, and moreso, only limited modifications, only those listed. It is NOT the philosophy of the class to find unlisted modifications that are somehow similar to those listed, and claim that those are (or ought to be) legal too.

But I say that when you are allowed to upgrade something like an engine (oil coolers and bigger radiators) and allow R&P's to be free AND limit to a stock case, allowing a fluid cooler there is certainly in line practically and philisophically.

In the same vein, I say no to tranny coolers because we aren't allowed to upgrade the units in any way.

[StephenB]

Who said you "are allowed to do anything to the rear end?" That's not true. 9.1.3.D.4 lists the only modifications that can be made to the final drive. If you could do "anything", it would say so. But it doesn't. It says that you can change the final drive ratio, and that you can replace the differential. You can't do anything else, it's that simple.


So this is one thing I hate about typing and the internet... I apologize that you mis-understood my intention when I was typing. When I said "anything" I wasn't really thinking of things outside of those items listed. To me those are the only things I could think of that would normally be done. When typing I meant changing it to any final drive ratio (And/Or limitied/welded diff) which gives the largest competitive advantage of anything I can think of that you can do to the rear end componant. I am NO expert and I was thinking just these simple things that we can do that gain a LOT of competitive advantage already. I never intended for this topic to involve crazy wild things.



The philosophy of the class is limited modifications, and moreso, only limited modifications, only those listed. It is NOT the philosophy of the class to find unlisted modifications that are somehow similar to those listed, and claim that those are (or ought to be) legal too.

If your trying to get in any type of pissing contest leave this thread now, I am NOT willing to argue. Please read the first post I posted again and understand I wanted to know how others felt. I have never said that I am claiming anything should be legal, I was just curious what others thought. To be honest if the search function found the other thread that is attached in the begining I never would have asked for anyones opinion.

"What are you thoughts about allowing Rear End Diff Coolers into IT? To far of a stretch based on the philosphy of IT? If I do run one can I disconnect it when running IT events or would that still be considered a no no just having it part of the car.

Interested in what you think..."

Stephen

[Knestis]

... I never intended for this topic to involve crazy wild things.

Behold to the power of rules creep! Shazzam!

Seriously though, this IS how it works. If someone thinks this is an appropriate allowance, propose the change and let the system hash it out. It's not currently allowed, but that won't stop the driving motivators behind the inevitable force that moves rule mountains.

K

[Chip42]

HA! Oil coolers and radiators are almost free now so that's moot.
so? This has nothing to do with radiators and oil coolers other than *maybe* precedent. what if want to add my theoretical diff cooler where my evap purge assembly (under trunk of a lot of newer cars) or my canister is?


In the same vein, I say no to tranny coolers because we aren't allowed to upgrade the units in any way.
transaxle?

I'm not actually arguing for anything - like I said I don't see diff coolers as being outside of the philosophy, just currently not legal and without enough evidence to convince me that they ought to be.

[JoshS]

If your trying to get in any type of pissing contest leave this thread now, I am NOT willing to argue. Please read the first post I posted again and understand I wanted to know how others felt. I have never said that I am claiming anything should be legal, I was just curious what others thought.

Stephen, no pissing contest intended, that's really not my style either. Sorry it came across that way. Your first post was great (and I guess it's obvious that I think a proposal like that is unnecessary rules creep), I was responding to what I interpreted as the notion that since other allowances are allowed for the rear end, then it makes sense to take it a little bit further to allow people to make everything of those other allowances that they could be. I guess you didn't mean that, so, my bad.

But, others definitely feel that way, I hear it all the time. That thought is analogous to saying that since we are allowed to run sticky tires, we should allow [insert your reliability fix here] because the chassis isn't up to racing on those sticky tires.

[Andy Bettencourt]

what if want to add my theoretical diff cooler where my evap purge assembly (under trunk of a lot of newer cars) or my canister is?

Just because you want to doesn't mean you need to.




I'm not actually arguing for anything - like I said I don't see diff coolers as being outside of the philosophy, just currently not legal and without enough evidence to convince me that they ought to be.

I am just making a point that diff coolers are most certainly within the philiosophy and are congruent with the allowances already in the ITCS.

[seckerich]

Steve,

This is for my RX8 with a Grand-AM rear end. Do you happen to know the temperature that is acceptable before they do die? How long before you guys started seeing failures? Was it length of time on track per session, or time on track total? Did changing the diff oil more frequently help... is it needed every session, weeknd, or season? Do you have any suggestions on the best Diff fluid that I should use?

Stephen

PS: I TOTALLY agree that the allowance of a diff coller would allow me to have a competitive advantage over others simply by allowing me to run this rear end safely without the gamble I am going to take. This is why I asked if it was within what others thought was the philosophy of the class. We are allowed to do anything to the rear end which is within the philosophy of the class, this allowance just makes those modifications we are allowed to do more reliable.

Thanks for everyones opinions.

I think what you will find Stephen is that a lot of the diff temp problems in GA were due to the restriction that the stock LS unit be used. They suck and generate quite a bit of heat. The 5.12 is still very stressed in these cars and even more so than the RX7 because of the 9000+ revs that see over 10,000 rpm on the drive shaft. I drop the fluid every race weekend with the RX7 and after practice, before the race at tracks like CMP. Get the gear rem finished if it is not already and buy fluid in 5 gallon buckets to save money. I have always run Mobile 1 75/90 in the RX7 with no failures even in a 13 hour race. The Castrol we run in the GA cars was also very good. If you put AN caps on the diff cooler outlets on that GA setup I doubt anyone will care that you have an extra drain hole.

[Chip42]

Just because you want to doesn't mean you need to.
exactly

[Andy Bettencourt]

exactly

But you are using the outlandish to squash a perfectly legitimate - and congruent - allowance. We are allowed to mod the internals, why not allow us to cool it?

FWIW: I have no need for a diff cooler.

[Chip42]

But you are using the outlandish to squash a perfectly legitimate - and congruent - allowance. We are allowed to mod the internals, why not allow us to cool it?

FWIW: I have no need for a diff cooler.

no, I was using an outlandish argument in an attempt to get to the statement you made about want =/= need and to try and illustrate the creep. the latter wasn't so effective.

like I said, I have no position for or against trans and diff coolers, but I don't think they are necessarily outside of the philosophy. I will add that if I were to argue for one, I would argue for both trans and diff on account of the unbalance of the rule granted to transaxles if it were awarded only to diffs

[Andy Bettencourt]

no, I was using an outlandish argument in an attempt to get to the statement you made about want =/= need and to try and illustrate the creep. the latter wasn't so effective.

I knew what you were driving at but it wasn't a good example to go to that extreme in a legit request like this.


like I said, I have no position for or against trans and diff coolers, but I don't think they are necessarily outside of the philosophy. I will add that if I were to argue for one, I would argue for both trans and diff on account of the unbalance of the rule granted to transaxles if it were awarded only to diffs

A fair position and one that would have to be considered by the CRB in both transaxle and FWD cases.

[Chip42]

I knew what you were driving at but it wasn't a good example to go to that extreme in a legit request like this.

The request is legitimate, I agree. but I don't think that my statement was THAT outlandish. sure the "reason" I implied was facilitation of instalation, and that is intentionally absurd, but I think that removal of the evap system in particular is within the class philosophy and the philosophy of the SCCA comp rules in general. and it certainly would help instalation of other "legitimate" requests :rolleyes:

power steering is one of those things I see significant IT philosophical dischord with as 2 cars with the same factory hp rating and same engine might have multiple spec lines, one with and one without the power steering, and show the same process weight, even though PS can sap a significant amount, particularly from smaller motors.

a good example is the honda civic DX 92-95, ITB: 4door and coupe came WITH PS, no option. 3 dr came without. same weight, same engine, 3 spec lines (by body style). this is correct according to the process, as the thing assumes a motor's gains, but if the losses associated with non-removable items are not accounted for by the factory then they are not accounted for by the process. but in this case, seperate spec lines breed unmatched cars. Does this fall under warts and all? could it be argued that the 3-box cars have advantages over the 2 box hatch? sure. but there is fundamental process dischord based on the factory's failure to list seperate hp numbers by equipment (an oversight in SAE net rules). by the same token, single spec cars that are currently well-processed could become too fast by such an allowance.

So I'm not convinced there is need for or that it is a good Idea too eliminate PS, but it is a legitimate request. I feel the same way about diff coolers.

[Knestis]

Your Civic DX example is a good one but that's a spec-line problem, not a process problem. The ITAC should make a decision re: whether derivatives belong on the same spec line - thereby authorizing update/backdates among them - or on different lines. If the answer is "different lines," then it does become a warts-and-all issue.

I'm not terribly confident that the various Hondae spec-line placements are the result of comprehensive planning and decision making, so it might deserve review.

K

[Chip42]

Your Civic DX example is a good one but that's a spec-line problem, not a process problem. The ITAC should make a decision re: whether derivatives belong on the same spec line - thereby authorizing update/backdates among them - or on different lines. If the answer is "different lines," then it does become a warts-and-all issue.

I'm not terribly confident that the various Hondae spec-line placements are the result of comprehensive planning and decision making, so it might deserve review.

K

actually, they were split into multiple lines based on a letter I wrote asking for clarification of UD/BD, particularly with regard to power steering, and if it is intended to be per spec line or per 100% as delivered for sale in the USA. between wheelbase, body style, and power steering, you get 3 spec lines for the civic DX.

my analogues at that time were the Ford Escort GT/LX-E in ITA (same cars under IT perspective, different body types) and the Honda Accord LXi/SEi in ITB (SEi is 2dr only, rear disks, LXi is 2 or 3dr, drum rears. otherwise they are identical to IT rules). I supposed that either we merge everything into one line (escort) or split based on a single feature crossing body types into a combination never sold in the US (accord). they chose option B.

[JoshS]

I supposed that either we merge everything into one line (escort) or split based on a single feature crossing body types into a combination never sold in the US (accord). they chose option B.

That's right, it was an explicit decision.

[StephenB]

Yaya old thread revival but figured I wouldn't create a new one for no reason. I am adding in a cooler that I can easily remove when running in ITR. I found this unit at summit racing and it seems easy and simple with a nice shroud but much cheaper than the fluidlyne. I was going to go with a mocal but not sure what fan to go with it and then I would have to fab up a shroud to go with it...

Griffin all in one cooler with fan http://www.summitracing.com/parts/gri-cxu-00002/overview/

Mocal I was also considering. http://www.racerpartswholesale.com/product/4992/Mocal_Oil_Coolers2

Thoughts? Other than illegal for ITR.

[MMiskoe]

You think you need the fan? Seems that getting the oil out of the lump and through the cooler would be quite a benefit even if the cooler didn't have great airflow. 10 years ago I remember seeing Winston cup cars that had the cooler up near the rear axle, a small amount of ducting, but no fan. I'll be curious how other people view this, but I suspect airflow from the car's motion will render any fan an impediment once over about 50 mph.

What will you use for a circulation pump?

FWIW I found when doing engine oil coolers the cost of the cooler could get eclipsed by the cost of the fittings and hose to plumb it all up. Them AN fittings ain't cheap.

[StephenB]

Matt, it is going under the rear trunk, not sure it would get a ton of airflow through it.

[Flyinglizard]

If you tap the cover for the outlet , in line with the ring gear, you can get it to work without a pump.
Keep the return line lowish, under the full level and it will work amazingly well .

[StephenB]

Others mentioned that to me but with the coolers mounted higher than the diff that worries me and to be honest I am certainly not an engineer or machinist! Keeping it traditional with something like a tilton pump seems easier for me to handle and should be reliable. The cover does have a fill hole up high and a drain plug down low so I was planning on using those to plumb it. Then put in an adaptor for my auto meter gauge so I can still monitor temps ( which is literally pegged after 5 or so laps at 300 the way it is now) and another adaptor for a thermostat that would turn on the fan and pump at 185. ( and turns back off at 165)

Stephen

Thanks for all the advise many of you are way more knowledgeable than i am with this!

[Flyinglizard]

Discount sells a rad fan controller for 40$ that can be externally zip tied to the hose/housing etc..
Reduces leak points and can be set to come on and off over a wide temp range.
Regarding thermo siphon ,as long as the hot oil line runs up hill a little and is at or under the upper level it will flow. Mount the cooler so that the hot oil flows up hill . You do have to bleed it out a little as an air bubble will slow it down.
The ring gear cranks it along pretty well , esp synthetic that I assume you are using.

[Matt93SE]

I think you'd be surprised how much airflow you get under the car.. if you want a fan to move air, go right ahead. But I think you'll be pleasantly surprised how much cooler the diff runs with just a cooler installed to move fluid around.

That said, what fluid are you running? the 240SX clutch-type differentials installed on Prod cars (slicks) will burn up just about anything but Royal Purple. Redline will get sulphury due to the temps getting up above the temp capacity of the oil and causing it to break down and the sulphur separates out. stinky stinky!!

the only fix for that was Royal Purple had low enough friction that it would keep the temps lower and that wouldn't happen.

[StephenB]

We run redline heavy shockproof but with the diff cooler we want to run mt 90 ( probably redline). I already know the shockproof stuff is to thick for a cooler...

It is a torsen type 1 LSD so no clutches.

Stephen

[Eagle7]

Don't ask how I know that MT-90 will burn up your Mazda diff in short order. :shrug:

[Flyinglizard]

I dont put shockproof in anything lessthan 500HP. Mobil one gear oil works for me and my clients.

[StephenB]

Marty, I think most WC and GA cars are running it. What would you recommend?

Stephen

[Eagle7]

MT-90 is a GL-4 transmission oil. The diff needs GL-5. I've used Red Line, but have settled on Mobil 1, mostly because it's easier for me to get and I also use it in the transmission.