141 replies to this topic

[Mike Collins]

Now that you know it's possibly in violation will you be looking closer?

Look closer at what? They are not going to have Saul's easy to identify paint on them? This is the difference between the haves and have not's in SM.

I can probably come up with at least another dozen parts just like this, where only a handful of people "may" be able to identify it... With a part like this you can put an OEM part in one hand and the "special grease" part in the other and maybe, BIG MAYBE, a very trained person could identify it. BUT, even if said tech person could.... YOU COULD NEVER PROVE IT.... It's not like Saul engraves his initials on his special parts.

PS...If you are reading about this now...how long do you think this fix has been in place?????

[CruzanTom]

Look closer at what? They are not going to have Saul's easy to identify paint on them?

Well, the GCRs don't say Saul CAN paint the springs so the springs would be illegal if he did paint them.

[Qik Nip]

We are not talking about a speed improvement here we are talking about getting back to the real life expectancy of the component part.

What Frank said! If a differently / properly heat treated spring provides increased longevity and offers no performance enhancement, SCCA/NASA needs to approve it!
Rick

[SaulSpeedwell]

Saul,

Help me understand why the spring "tab" would break in the first place. It keep the spring from rotating inside the hub, but there is no significant rotational force on the spring other than inertia. The keys force the tab in and out of the locating hole when the clutch sleeve is moved during shifts, but they don't rotate the spring. Could the problem be the tab binding in the locating hole?

The keys as well keep the spring inside the hub by design, but without the tab and 6.9K RPM I could imagine how it could be spun out.

AC

As you and many others likely know, the tab/tang/bent part becomes very weak (work hardened) during/after the 90 degree bending operation if the spring isn't formed/annealed/tempered perfectly. That is the real problem here. In many other trans designs, there is no 90 degree bend, there may be a "hump" (Tremec) or a little stubby tang at each end (Borg-Warner), or a full circumference spring (Hondas).

You are right, the stresses going into the tang are not principally from rotation - it is from shifting. Each shift "cycles" the spring, and any vibration is a "micro-cycle" that will tend to reduce the life of the spring. In fact, I have found transmissions with broken springs that have luckily stayed in place enough to prevent a synchro failure. This is the rare exception, though.

If you have the subassembly from my video in your hand, cycle it a few times and watch what happens to the spring. There is friction between the sleeve and the keys, and friction between the keys and the springs. On worn springs you can see the witness marks where the syncro keys and locating tang are being "rubbed". So, the tang is really feeling stress from all directions - but in the "rotational" direction, it is only resisting the compression and relaxation of the spring hoop during the time the keys are cycling from flush to depressed to flush again.

Because we are shifting hard/fast/under higher load, the spring is getting more stress/strain than loafing on the street.

There are other, better, ways to solve this problem, but I wanted a solution that would pass tech in a 1990 Runoffs-winning Showroom Stock car with a balanced/blueprinted/cammed/milled Sunbelt, special shocks from Mazda, etc.

[SaulSpeedwell]

The keys as well keep the spring inside the hub by design, but without the tab and 6.9K RPM I could imagine how it could be spun out.

AC

Oh! Video clarification ... I didn't mean to suggest the spring actually leaves the inside of the hub after the tang breaks. The spring still stays inside the hub where it belongs, except it rotates so that one of the keys loses its support.

[Tom Sager]

As you and many others likely know, the tab/tang/bent part becomes very weak (work hardened) during/after the 90 degree bending operation if the spring isn't formed/annealed/tempered perfectly. That is the real problem here. In many other trans designs, there is no 90 degree bend, there may be a "hump" (Tremec) or a little stubby tang at each end (Borg-Warner), or a full circumference spring (Hondas).

If an improved spring were to be designed, is there room in the assembly to make the spring slightly larger in diameter (stronger)?

[FTodaro]

As the shift hub wears it gets a little notchey and it takes more force some times to get it in gear. I have broken them I think, when I have missed a shift and I jam it into gear.

Now I change the oil after every race, not because I think the oil is bad, I do it to look to see what's on the magnet. If I have a little piece of square spring on the magnet, I know I have to pull and replace that spring.

For me that is a good 8 hrs of work if I Am going to totally dissasemblle and assemble a box.

[SaulSpeedwell]

If an improved spring were to be designed, is there room in the assembly to make the spring slightly larger in diameter (stronger)?

Not much room, but I don't think wire diameter is a solution, anyway. The spring design itself is fine, were it not for the dumb choice of the 90 degree tang.

It believe it would still fail at 20% larger wire diameter because the tang's stress riser/work hardening is overriding all the normal fatigue calculations ... meaning any paper clip is going to fail where you bend it 90 degrees, regardless of the wire diameter. But if we manufacture it right, those 90 degree areas will still hold up to normal use. (like "Regal Clips" versus "Trombone Clips").

Should have some more videos for discussion and amusement later today ...

[SaulSpeedwell]

Vids 2 and 3 ... hopefully ...

[john mueller]

Look closer at what? They are not going to have Saul's easy to identify paint on them? This is the difference between the haves and have not's in SM.

I can probably come up with at least another dozen parts just like this, where only a handful of people "may" be able to identify it... With a part like this you can put an OEM part in one hand and the "special grease" part in the other and maybe, BIG MAYBE, a very trained person could identify it. BUT, even if said tech person could.... YOU COULD NEVER PROVE IT.... It's not like Saul engraves his initials on his special parts.

PS...If you are reading about this now...how long do you think this fix has been in place?????

I see 'modified' parts like this as a cost containment and reliability issue much like allowing the 1.6 a Torsen (saves everyone DNF's and money in the long-run).

Yeah, I see no infraction here, in fact I'd welcome allowing it and would push to include it in the NASA rules. Our collective rule sets are already overly detailed, I'd be up for adding a few more parts that would further close the 'have & have not' gap. Which BTW, should not exist in a spec class, that's the whole e'ffing point of racing in a spec class.

So, now that the cars are now pretty equal, lets equal-out the experience levels too! Yee-friggin-Haw !!!

Saul (or anyone else who knows the 'secrets'), you ready to produce a boat load of these clips/springs and the others eluded to? Message me.

[SaulSpeedwell]

If an improved spring were to be designed, is there room in the assembly to make the spring slightly larger in diameter (stronger)?

As the shift hub wears it gets a little notchey and it takes more force some times to get it in gear. I have broken them I think, when I have missed a shift and I jam it into gear.

Check here or your PM box in the near future, I made a video that responds to both issues ...

[SaulSpeedwell]

If an improved spring were to be designed, is there room in the assembly to make the spring slightly larger in diameter (stronger)?

As the shift hub wears it gets a little notchey and it takes more force some times to get it in gear. I have broken them I think, when I have missed a shift and I jam it into gear.

Video attempt to address both comments ...

http://youtu.be/d1jWnzqkpjQ

[Tom Sager]

Mark, really appreciate the info and the effort. There should be a decent market for the better spring with or without a rule change. I suppose a request can easily be made to both SCCA and NASA to add this to the list of non-OEM parts that are allowed to make it legit. I'll write a couple letters.

It looks like the URL www.speedbysaul.com is available.

[Keith Novak]

As a former stress engineer who could not try to help explain this without making it far more complicated...I fully endorse this message.

[Cnj]

As a former stressed engineer who could not try to help explain this without making it far more complicated...I fully endorse this message.

Fixed that for you.

Cnj

[SaulSpeedwell]

Gah ... posting problems ... will try again later ...

[SaulSpeedwell]

As a former stress engineer who could not try to help explain this without making it far more complicated...I fully endorse this message.

Keith, I'd be curious what you make of this? I have some metallurgy bona fides from another life, but I don't know how grinding/polishing might affect such a thin piece as these, especially since we're not sure how Mazda is processing them.

I don't want to ruin any of the improved springs just to figure out if grinding/polishing would affect them.

http://youtu.be/ZnY7hejSYIE

http://youtu.be/mgauNM7VZLM

[38bfast]

Speedwell, While there are many words in the dictionary to describe things. Exciting would not be one I would have chosen for testing Miata springs. What word would you use to describe when you are on track?

[Tom Sager]

Masterbatacular? Some guys drive with one hand on the wheel.

[SaulSpeedwell]

Speedwell, While there are many words in the dictionary to describe things. Exciting would not be one I would have chosen for testing Miata springs. What word would you use to describe when you are on track?

Ralphius, I have dedicated this week's "exciting" video to you!

(The one word I would use to describe when I am on track is: Methylchloroisothiazolinone!!!)

http://youtu.be/GYqddHuEDYE