gear sets? What is stock?

Protech Racing

Well-known member
Maybe Greg Amy can clarify this..STL just clarified "gear sets" and the CRB said that it means 2 gears. Thus Honda can use any choice of gear pairs to make a legal " stock box". Seems like a big help to low torque engines.
Listening to the vids of the front cars, the Hondas seem to have really nice ratios, Jasons' Toy has a really tall top gear and the VW some place in the middle.
The LBC all sound like GT cars and dog boxes. the best sound of all.
WE need to also clarify this if anyone thinks that it matters. I really dont know what gears are in my VWs as they mix amd match a little also. 2nd and 5th gears mostly.
MM
 
Mike, Prod is not like IT, where they specify a particular gear set for the spec line in your car, and the only option is the R&P.

My take on the Prod gearing is that as long as your using the same "stock" gears, and have not changed the engagement type, that you could use any 1st, 2nd, 3rd, 4th, or 5th gear you want.

Now that I read it again, it might fall into the 2.5% weight penalty, but the definition of "stock ratios" is what needs clarification. Maybe somebody needs to write the CRB and ask for a clarification of the "stock ratios" in Prod.

The Transmission is unrestricted, providing that it is fit in the same basic location as stock. Sequential shifting transmissions are prohibited. Pneumatic, hydraulic or electric actuation of the gear shift mechanism is prohibited.

There is no weight penalty for the use of a stock transmission utilizing stock case, gear ratios and synchromesh style gear engagement. An alternate transmission that uses stock type, circular, beveled synchronizers, imposes a 2.5% weight penalty. An alternate transmission that uses a gear engagement mechanism different than stock type, circular, beveled synchronizers imposes a 5% weight penalty.
 
Here's the transmission rule, for L2 in prod:

There is no weight penalty for the use of a stock transmission
utilizing stock case, gear ratios and synchromesh
style gear engagement. An alternate transmission that
uses stock type, circular, beveled synchronizers, imposes
a 2.5% weight penalty. An alternate transmission that
uses a gear engagement mechanism different than stock
type, circular, beveled synchronizers imposes a 5% weight
penalty.

Since the phrase "gear ratios" is used, you cannot swap gears from one position to another, and still call it a stock gearbox. If I protest your stock gearbox, every gear must have the stock ratio as delivered by the factory, or you're not running a stock gearbox. Easy peasy. Change the ratios, and you just made an alternate box, and must carry a weight penalty.

An interesting question would be, if the base model on the same spec line (from a different year) offered a different ratio for the same gear, would that still be considered stock? I think you'd have a good argument for it. There's nothing in the above rule that says the entire transmission is considered a unit - meaning its parts are legal to interchange with parts from a different year. That's why there's years on the spec line - all those cars are considered the same.

If you really want to split hairs, the definition of the stock gearbox requires you to use stock case, ratios, and syncromesh engagement. It doesn't limit what you can do to the gears themselves, or the syncros, if you felt there were some advantage in hardening, REMing, changing to steel syncros, etc. The only requirements are case, ratios, and syncromesh.
 
In the VW A1 Chassis, there are like 6 trannies that span from 1975 - 1984. Some with different ratios, R&P, and of course 4 and 5 speeds in the mix.

I do agree that if you change a gear ratio, it's not stock any more, and you need to run the 2.5% weight penalty. That's what Lawrence said and did.
 
Moved from another thread:
Jason@SportsCar":3av1z2ao said:
I think the gray area comes from the allowance to update/backdate, if you can use another trans from your spec line you can have "different ratios" without a penalty.

Protech Racing":3av1z2ao said:
STL just clarified "gear sets" and the CRB said that it means 2 gears. Thus Honda can use any choice of gear pairs to make a legal " stock box".

Allowance to use another gearbox from a car on your spec line is not the same as using gears out of another gearbox. I don't know what the STL rules say, nor do I think that it applies to Production cars, but the rules for level two production cars say the transmission must have stock ratios. I wouldn't think that would mean mix and match gear sets from different boxes. The 2 1/2 percent penalty allows you to use any gear as long as it uses synchronizer cones.

From listening to in-car audio from a few years ago and comparing it to recent ones it would seem that a few cars have closer ratio gears. I assumed that the weight penalty was part of that change. If not I am........surprised.
 
I think the intent of the rule is stock, not picking and choosing ratios across years and models. Update/backdate is a very smart usage of the rule as written. If anyone wonders why the rule book is so thick, here's the reason. Smart guys find the loopholes.

Probably needs clarification.
 
I think the interpretation has obviously always been what Loshak did. You can use any stock set of gears at weight, you can mix and match stock style gears at +2.5% and you can run any set of ratio and/or dog gears at +5%.

The only thing that muddied the water here is the subsequent "definition of a gear set" to be a pair of cogs. I would argue that the correct term for that is gear pair, and that a gear set is the complete set of cogs that come inside a transmission. Unfortunately this does now need to be clarified.
 
My take:
Stock Gearbox - can be any stock box update/backdate as long as available from factory with the gear ratios as per that specific box - mix/match not allowed as it isn't available from factory that way
+2.5% - any gearbox if it's syncromesh - could be a quaife or whatever, if syncro, ratios are completely free. If you use another box from the factory that isn't in the spec line or modify ratios in a stock box
+5% for dog box

ie:
My car stock spitfire box
run a GT6 gearbox or put in competition department gearsets +2.5% or a quaife or a TR7 box or a Honda box
my gearbox +5%
 
Thanks Aaron. That was what I was trying to say a bit less clearly. I mixed up the syncro/dog distinction between 2.5 and 5% adder.
 
The STL clarification was to allow using any oem ratio from any oem gearbox that would fit with no modification. It is in the ST rules so has no bearing on Prod.

My interpretation has always been stock gear ratios (as a set)/syncro = no weight

Change a ratio/gearbox/w syncro +2.5%

Take 5% and do whatever
 
Guys, I agree with you and was my stance on the discussion. I ran at 2229lbs, carrying the 2.5% penalty.

A big argument I also had when I was considering to take the gamble was... Again heres the rule:

There is no weight penalty for the use of a stock transmission
utilizing stock case, gear ratios and synchromesh
style gear engagement. An alternate transmission that
uses stock type, circular, beveled synchronizers, imposes
a 2.5% weight penalty. An alternate transmission that
uses a gear engagement mechanism different than stock
type, circular, beveled synchronizers imposes a 5% weight
penalty.

So, read the first sentence again. It says, STOCK transmission (basicaly cant go to a different gear box, more speeds, different design etc), STOCK case, gear ratios and syncromesh engagement. It does't have the word STOCK in front of gear ratios and syncromesh.

Another thing I wanted to point out and help avoid... Dont make it acceptable only if you use a OE part. Because unless you have a Honda or similiar, you wont have anywhere near the same amount of options. And who cares who makes it as long as it fits and is the same design as the gear it replaces. Policing this would be a nightmare too. What if fine, I made a gear that is a exact gear Honda made... Should that carry a penalty? How would I prove it was actually OE?

Lets put aside what we thought the intent was for a second. And maybe brainstorm a solution to put this to rest. Im sure no one wants the surprise one weekend where they grab a bunch of cars to try to figure out their ratios. That would be a lot of fun, not!

A big thing to consider is who is going to police this? I have never seen anyone checking gear ratios. And this is a very common and easy upgrade. Not to mention, very cost effective.

IMHO, regardless of the intent or whatever... As long as the gears are OE, syncro type, OE gear type, it shouldn't carry a penalty. 2 big reasons, 1) to hard to police check etc 2) some cars come with brilliant boxes some dont.

I say open it up and move on. Its still up to driver skill to go up and down smoothly.

Adapt the STL rule.
 
SPEEDSHAK":1a7u78yh said:
Guys, I agree with you and was my stance on the discussion. I ran at 2229lbs, carrying the 2.5% penalty.

A big argument I also had when I was considering to take the gamble was... Again heres the rule:

There is no weight penalty for the use of a stock transmission
utilizing stock: "case, gear ratios and synchromesh
style gear engagement". An alternate transmission that
uses stock type, circular, beveled synchronizers, imposes
a 2.5% weight penalty. An alternate transmission that
uses a gear engagement mechanism different than stock
type, circular, beveled synchronizers imposes a 5% weight
penalty.

So, read the first sentence again. It says, STOCK transmission (basicaly cant go to a different gear box, more speeds, different design etc), STOCK case, gear ratios and syncromesh engagement. It does't have the word STOCK in front of gear ratios and syncromesh.

The primary issue here is the word AND. If it said "Stock case, gear ratios, OR syncromesh" then your interpretation would be more appropriate. However, it says "and", which implies that all of the conditions must be met. i.e. stock case, stock gear ratios, stock synchromesh.
That's my $0.02..
 
Yes, I agree with you but... Stock was printed twice not 3 times. If it said stock transmission, case and ratios. Your grammer example would be correct. Since it says stock transmission, stock case (no billet, carbon replacements), gear ratios (so no CVT, dual clutch etc) and synchro style engagement (no dog boxes). It can be argued that any gear ratio and synchros can be used because it does not say stock in fornt of those words too. Again, maybe not the intent, that's not the argument. Its whats written and it does allow a loop hole.

BTW, since we're here. Do syncros have to be OE? If they're the same design, cant we use aftermarket ones? If so... Is that "stock"?

We need to consider how were going to police it.

Please also remember this argument and really think about this... if I use stock gears (OE), out of a different model within my spec line, then thats legal? AND how would I prove they were stock? Pull out the trans after qualifying and tear it open? Before my race? Because keep in mind, what I did with my gearbox, I moved gears around and could have used stock gears to achieve the similar results.

Also keep in mind the availability of gears for a newer car vs older prod cars.

Things that make you go hmmmmmm.
 
I have no dog in this fight (did you see what I did there .... ;) ). Just a question.

"Alternate" - does this allow for straight cut gears?

The rules seem to focus on the engagement mechanism rather than gear tooth design. Without calling Jamie, I'd guess that straight cut gears are worth more from a lap time perspective than dog engagement is. Especially at a track like Daytona. So if you're taking the hit for "alternate", you're leaving meat on the bone by not going to straight gut gears.

-Kyle
 
I'm having a hard time listening to the "how do we police this" argument. Quaife makes alternate gearsets which are legal (with the 2.5% weight adder) for many vehicles stock gearbox cases.

We already have to police those - so if that's an issue, it's an issue regardless of what the SCCA meant with its "stock gearbox has no weight penalty" rule.

I think we agree that mix-and-match gears from all years of a car's spec line are legal, as long as they fit in one of those year's stock boxes.

Where I keep having a problem is, there is in fact a spec for each gearbox as to what the specific gear's ratio is.

Since each gear has a spec to its specific ratio, I don't see how you can change that ratio from stock, and not incur the weight penalty.

So, it really boils down to "What can I do to my stock gearbox, and avoid the 2.5% weight penalty."

Letter sent. Tracking Number: #15780.

I hope I just upset the applecart; some manufactures don't offer different gears that can be swapped from box to box. The intent for changing gear ratios, from the manufacture's spec for each gear (by whatever method) should incur the 2.5% weight penalty. There's just no way cars were classed knowing which manufacturers had this ability.
 
Changing gear ratio's will improve performance, correct, so how is that still "stock transmission"?

My car was over weight, so I converted to a alternate gearbox, now I am very close to min weight. Solved several problems at once....
 
blamkin86":mjuhpm3a said:
I think we agree that mix-and-match gears from all years of a car's spec line are legal, as long as they fit in one of those year's stock boxes.
I don't agree with that at all. If you want to use the update backdate option, you could make a case for using ALL of the gears associated with a gearbox from a car that shared your spec line, or more precisely you could use the actual gearbox itself from another car on your line. But mixing and matching means you are creating a non-stock ratio because stock gearbox defines a particular set of ratios. There is no way that they mentioned ratios without trying to define them as stock.
 
This isn't exactly a new problem. Porsches started sliding different gear ratios into their transmissions back in the late 50's. So, then other manufacturers started making different, read optional, gear sets, and the march goes on.
 
Ron Bartell":2ql814l6 said:
[mixing and matching means you are creating a non-stock ratio because stock gearbox defines a particular set of ratios. There is no way that they mentioned ratios without trying to define them as stock.

You have to admit, it's an interesting question. I should go look at the update/backdate rules and see what has to be considered a unit.

Hopefully I've worded my CRB request in a way that they will answer reasonably. You may want to consider sending one based entirely on the update/backdate inside the transmission; I didn't mention that specifically.
 
Back
Top