Miata 1.6 Torsen

Mseiler

Mseiler

New member
After a season and a half in ITA and two blown viscous diffs, I put a torsen in my 1.6 Miata last summer. I've now been told "I won't protest you but, you're illegal". This past weekend I would have had to replace another diff thanks to the thumps in the rear during qualifying were it not for the torsen.

Is there any support from the 1.6 drivers or objections from 1.8 drivers to seeking to allow the torsen in the 1.6?

I did not change the lsd to get an advantage other than durability and I don't see any improved performance.

I'd like to hear some thoughts before seeking to gain this exemption.

Thanks.
 
drive shaft & drive axles.

I thought they were free as well but, I have a competitor that insists that's NOT the case, since the 1.6 only came with viscous and the torsen started in 94 with the 1.8
 
Mseiler said:
drive shaft & drive axles.
Click to expand...
Yeah, that would make it technically non-compliant to the IT regs. Diffs are "free" as long as you don't have to make mods to anything else to make it fit.

Doesn't hurt to ask, but I think that was actually requested in the past and denied. It's not really a decision made through approval of your peers/competitors*, it's a decision to be made by the CRB in regard to the base IT philosophy.

- GA

* One can, effectively, gain "approval" from peers through a nudge-nudge-wink-wink-we-won't-protest-you kinda local deal, but if only a single person chooses not to accept that "gentleman's agreement" you will lose the protest and appeal.
 
My goal is to see if I'm the only one that would like to see it allowed and find out if there are any absolute objections out there among the ITA herd. And, if so, why.
 
Locally, you probably won't have a problem as long as you talk to your competitors and get their 'wink' like Greg said.. As far as getting the rule changed Nationally, I am sure you aren't going to get anywhere. Rule suggestions based on 'reliability' are not usually (can't think of any) something the ITAC/CRB approves.

Get creative. What can you do INSIDE the case to strengthen up your unit? Have you talked with some of the top Miata prep shops in SEDIV?

Are you running Mazdacomp version of the viscous or straight stock?
 
It's a weakness in the pinion. The viscous is fine, performance-wise. The problem is when you get bumped and the tension is released then it snaps back weakens and can break the pinion.

The suggestion I've gotten? Get a Torsen...
 
Mseiler said:
It's a weakness in the pinion. The viscous is fine, performance-wise. The problem is when you get bumped and the tension is released then it snaps back weakens and can break the pinion.

The suggestion I've gotten? Get a Torsen...
Click to expand...

Upgrade or modify your pinon for strength.
 
as the 90-93 diff housings become more difficult to come by, a la 12A parts, it would seem to be a viable alternative.

Any other 1.6ers have an opinion or suggestion?
 
I think all this talk about free diffs might be misleading. The guts are free, but I don't think the housing is. Put whatever you want inside the 1.6 housing, but don't substitute the 1.8 housing.
 
Correct, Diff guts are free, casings are not. And obviously, axles and driveshafts are not open.

If there is a pinion strength issue, work to correct that, maybe even while trying a new FD.
 
What about running at 1.8L weight?

Bottom line, I don't have the engineering expertise or $$ to reinvent the 1.6L viscous LSD to make it as bullet proof as the torsen.

A driver in a 1.8 that I beat in the Saturday race ran into me twice entering T11 at CMP on consecutive laps in morning warm-up. No one called him on it and were it not for the torsen my weekend would have probably been over.(sorry, no refund, you turned a wheel). I know we are now getting lower insurance due to our "no metal to metal" rule but, that doesn't fix my diff.
 
There are Comp diffs available that fit in the 1.6 housing. call Mazda

Same with the power steering rack, it can not be de-powered, it must be a manual rack.
$560 new from Mazda, good luck finding a used one!
 
When I was running my 1.6 I found that if you have the R&P cryoed and REM polished (legal, R&P are open, and "If it says you can you bloody well can") and changed the fluid EVERY. SINGLE. WEEKEND. I could get 2-3 years (15ish events) between breakages...

AND once I started having the R&Ps cryo/REMed BOTH times I broke one it was obvious abuse" jumping the everliving crap out of the turn 3 curb at Road Atlanta WFO chasing Tom Long, right after my wife spun the car in a huge way while staying on the gas.
 
thanks for the cryo and manual rack info.

Luckily I've got a manual rack in my daily driver. Not sure what I'm gonna do about the diff since my local competition is OK with it.

I'll probably approach TPTB to get a waiver, even if it fails I know it won't be done if I don't try(yes, I can relate to RP McMurphey) so if any other 1.6 drivers want to join me in the effort I'd love to have your support.
 
speaking for myself, not the rest of the ITAC, you could have a letter from every 1.6L Miata driver in SCCA, everyone running ITA, all the stewards, a bunch of mazda engineers, and the pope, and I still wouldn't approve a change. this is bread and butter IT principle stuff and it doesn't need to change.

besides:

there are legal solutions out there.

the Miata has a track record of success.

So it's in a better spot than 60% or more of the cars in the ITCS with similar issues. Sorry Mark but this is way bigger than one car.
 
Ive been following this and it seems as though the solution is simple and makes a more effective car. Albeit will be a time consuming expensive venture.

VIN is not required in IT

1.6 car has the weak rear end due to size issues. Cant update to the better 1.8 housing,R+P, and diff. Not on the same spec line.

Change the engine to 1.8, upgrade the rear diff to the 1.8 piece, upgrade the brakes, and build a better moustrap. Besides the 1.8 car has the better airflow meter and intake.

The worst thing the OP did was ask the question. Now we all know what he is doing.

This is nothing worse than an IT7 1979 RX7 with drum brakes and small axle bearings that has upgraded to an 85 disc brake large bearing rear axle assy. or a 79 chassis with an 85 nose on it so we can get the airdam that works the best. Problem is they are all on the same spec line. Thats the issue at hand.

Just sayin'

Dan 77 IT7
 
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Chip42 said:
speaking for myself, not the rest of the ITAC, you could have a letter from every 1.6L Miata driver in SCCA, everyone running ITA, all the stewards, a bunch of mazda engineers, and the pope, and I still wouldn't approve a change. this is bread and butter IT principle stuff and it doesn't need to change.

besides:

there are legal solutions out there.

the Miata has a track record of success.

So it's in a better spot than 60% or more of the cars in the ITCS with similar issues. Sorry Mark but this is way bigger than one car.
Click to expand...

What about running the 1.8 weight with a 1.6? Is that a problem? As it stands I have a car that is dependable, somewhat competitive and unable to be legal in its current configuration. SCCA is promoting the "no contact" policy but, in this case, 1.6 diffs, it's allowing a finger wag punishment for an expensive "oops, sorry" situation.

This really has come about because of being whacked in warm-ups, twice by the same car in the same corner and were it not for the torsen the weekend would have probably been over and then being told my torsen was illegal.

There is a reliable solution to weak Miata diffs that doesn't require expensive repairs. If that makes me a whiner, so be it.
 
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