THSCC Forums

Yeah, I'm running Amsoil racing gear lube, which is even better in my opinion. This indeed helps the crunchiness, but my 2-3 problem isn't really crunchiness. Its like the gear is locked out, it feels kinda like the 1-4 skip shift "feature" on the GTO. An easy shift sends me easily into 5th rather than 3rd. I imagine the new found torque only makes the problem worse, but it certainly existed before the S/C did. What is the torque limiting strap, and is this something I buy, or make?

Spec Miatas are well known for having troubl e going from second to third if you still have the car loaded to one side, particularly while stlil exiting a right hand turn like Oak Tree. On decent rubber you're way up in second through the corner and near limiter while still loaded pretty good. The torque put on the driveline in that situation is such that it takes a VERY precise shift to keep from going to fifth. "Slapping" it in gear simply WILL NOT WORK. You must grip the shift knob and be precise. Everyone I've talked to who drove Spec Miata much has that same problem with that corner.

It happens to different extents different places, but the result is the same. As I understand it, having a higher torque engine in there can cause pretty much the exact same problem even in a straight line. Add in manufacturing tolerances as well as something being potentially slightly bent, and Les' car may need tranny work to fix it. I drove it and agree that something is just plain off in that setup...I don't think it was just the added torque of the engine (and I certainly wasn't loaded to one side when trying to shift by enough to have mattered, I don't think).

(Also note that the Spec Miata issue I describe can happen with a brand new transmission with good gear oil. You're not allowed to put stiffer mounts or torque limiting straps in. But as long as everything is "good", you *can* make the shift happen without incident. It's just a little tricky and requires concentration.)


--Donnie

Oh, and while I'm here, a BIG THANKS to Les for letting me drive his car. It's a really fun car to drive. I gave him my ideas of what the setup felt like as I'm sure it can be better, but in reality it's DAMNED FUN just like it is. I mean real damn fun. Seriously fun. Did I mention fun?


--Donnie

a torque limiting strap can be made very easily. I have seen them made from a steel cable, a piece of sturdy chain, or a length of solid steel stock (not the best for a street driven car). Simply attach one end to the frame, and the other end to a point as high up on the engine as possible so it is in tension when the engine torques. Gun the engine, the strap should go on the side that trys to rise up. Adjust the length or mounting points so the engine can rock just a small amount when you gun it. I know Andy Hollis ran one on his CSP Miata as does Dan Pedrosa on his SM2 Miata.

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SPIN or WIN!
there's no glory for going slow.

Regarding Miata shifting:
Mines been good since I replaced the turret oil and boots. How many miles on the Miata Les?

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Not spectacular just decent.
I'm not sure what I'm driving.
Maybe an ITR in DS.
Or half-assed STX prepped 330.

Would something like this help? Connects from the block to the firewall.



Not to expensive to try either....

Linky

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02 Focus SVT
STF 9

I was very surprised by the overall grip at Sanford. Having just run Danville the previous day which I always thought had a lot more grip, I would have to say that Sanford was right there if not better. Heck, even the sealed parts were fairly grippy as far as I was concerned.

I think all you have to do is look at the PAX results from the tours and pros this year to see that the latest generation of r-compound tires are kicking some major booty. When the best drivers in the country on street tires can *barely* break the top-50 in PAX at the big events on any surface, I would tend to think the new r’s are far and away better than the previous generation.

From what I’ve heard so far, this may not change much next year since there aren’t really any new street tires on the horizon and Rick Ruth isn’t known to be a big fan of the touring classes. Not that it really matters since PAX is stupid anyway.

Jim

As others have stated, this is a known problem with a high-hp Miata. I always had to be very deliberate on the 2 to 3 upshift in my old turbo car or I would hit 5th every time. Well, one time I managed to get a mystery gear between 3rd and 5th which turned out to be neutral when I let the clutch out but it's essentially the same thing. This would only happen under full power otherwise it was never a problem.

I never really had the problem when the car was loaded up as Donnie stated but that was probably due to the fact that you really couldn't use full throttle in 2nd gear if you were turning at all. Anybody who drove it could probably attest to that.

I never really bothered trying to find a solution since I could hit third if I was being deliberate. Les, if your car was doing that before you added power, you might think about loosening all the motor and tranny mounts and retightening them. There is a little slop in there and perhaps something is slightly out of whack. Just a thought anyway...

Jim

I'd like to congratulate Rob on an excellent course as well. It definitely flowed very well and had a great mix of high-pucker sections and patience elements. Very nice job!

On a related note, it exposed yet another oddity in my '88 car -vs- later years. It turns out my fuel cutoff is 500rpms lower than I expected. I had to use 3rd gear in three places on course with a few sections leaving me stuck between gears. With all the talk about where people running out of gear and their resultant mph, I started to suspect something was off. All of the Civic guys I've talked to run out of gearing ~60mph with the size tires I'm running and a stock ECU.

I've run across a bunch of those radar-based speed devices you see in work zones recently and based on those, my speedo is fairly accurate in the 60mph range. To see where I was running out of 2nd I went down an onramp until I hit the limiter and much to my surprise, I was only going ~54mph! No wonder I have been hitting the limiter so early compared to most other Civics I've seen this year. After some searching on the internet, I found a few references to the '88 rev-limiter cutting in 500rpms sooner that the later years. Man, not only does the car make less power than the later cars, it can't even run up to the same rpms! Stupid car! I guess that's yet another reason to change my ECU over the winter months.

I'm hoping that's the last of the surprise quirks I find with the '88 model. If not, I selling the POS and getting another Miata!!!

Jim

I also want to thank Rob H and Mike W for a great course. It was very fun and would have been even more fun if I would have taken my head out of my arse for at least one run!!!!!

I want to thank EVERYONE for their patience with all the "Hold Starts" It was very hectic in the bus Sunday, what with 3 cars on course and all. Not to mention the Dookies car breaking every time they tried to launch!!!!

Also, I want to thank Mike W for fixing the wireless issue we had at the beginning of the event. The "back up" plan of having someone call "STOP" over the radio was looking like a possibility at one point. I don't think that anyone would have like that one bit. Good Job Mike!!!!!

As for my shifts from 2 - 3 and 3 - 2 in my car. They go very smooth but I do get a little crunching sound when I try to do it quick. I think I just need to slow them down a little and maybe it won't be an issue.

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Todd Breakey
STS 42 - 1992 Sunburst Miata
Dammit!
"You souldn't play leap frog with a porcupine. You might get hurt." - Eliza

Well it's settled then. The next time I chair an event at Sanford we'll just make the *whole* course 3rd gear, so no one has to worry about shifting.

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Mike Whitney
whit32@gmail.com, 919-454-5445
V10, V8, V8t, I6, I6, V6, F4t, I4, I4, I4, I4, I2, 1, 1

Sounds like a fantastic idea to me.

Having a single point of failure is kind of a problem. Do we have a backup plan? If not, I've got a couple of ideas using the wired timing equipment:

• Place the bus at the finish and synchronize a 'start clock' that start holds with a finish clock on the bus. Have start give a countdown from three every thirty seconds to send a driver. Someone on the TS team hits the start button every time 30 seconds elapses on the finish clock, unless there's a red flag or a hold start. Main problem with this is that it would result in a slightly different course than the timed one since the starts aren't equivalent, so prior times would need to be discarded if there's a failure during the event. You'd also need to periodically verify that the clocks are still synchronized. Cell phones that pull time from the cell tower might work for this.
• Place the bus at either the start or finish, but somewhere that looking out the bus window from the timing bench is exactly on line with the start cones. Have someone watch cars with a spotting scope (tripod mounted low-power telescopes that target shooters use to check targets) and hit start (or finish) when a car passes the start (or finish) cones.

Thoughts?

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1988 Plymouth Reliant

The transmission in my black Miata was really smooth. I don't recall having any issues with it ever, even on fast shifts. You could "grip it and rip it" with no consequences.

The tranny in my present red Miata has been totally the opposite. It was really notchy when I got the car and I bitched about it a lot. My first time with it at VIR full this spring resulted in a lot of grinding/missed shifts. The worst was a failed 5/3 shift at the end of the back straight, setting up for a right into the roller coaster. Did a 5/1 that shot the car sideways and allover the track before I reigned it in. I was kinda surprised that Marvin McB got back in with me the rest of the weekend.

At Rockingham I finallly got the the right technique drilled in my head by David Stone. DONT GRAB IT! Don't force it! You just push it in the general direction you want it to go with your finger tips (back) or the palm of your hand (forward). Also, No Fast Shifts. You have to "out - neutral - in" it and let the gear dogs (I think) have a chance to mesh smoothly.

Why did I miss a shift Sunday? I forgot everything I new about this car and rushed/forced the shift.

Both transmissions have recieved the same treatment - fresh Redline MT in the shifter turret with new boots, fresh Redline MT in the tranny. The redline didn't help much in the red car at first. After about 5k miles, I changed the tranny fluid again. It seems a little smoother finally. Don't really know if it's the Redline or just giving it proper shifting. Probably proper shifting.

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“I feel safer on a racetrack than I do on Houston's freeways.” - A.J. Foyt

Kevin Butler
Mobetta Autosport Spec E30 #612
2003 C5 Z06 Corvette
AFR Miata, SM2 61, '93 w/200 SC'd RWHP - soon to be resurrected
Waaaay too many other projects....

Me, too. As the raw sheets guy, the hold-up during the second heat was my fault, resulting in downtime and a couple re-runs. I either didn't record one car at the start (and didn't figure it out until several additional cars had finished) or a false start trigger occurred.

A couple 'issues' definitely contributed to this situation:

1. During that time, we had no 'buffer' - we were waiting for cars to come from grid to the start line, so each car was getting launched immediately as it came up from grid. Any distraction in the bus could easily result in missing a car coming up to start. AFAIK, this has never been an issue before (we've consistently kept several cars queued up at the start and/or announced car numbers at the start line), and I understood from the radio communications that the grid worker was having trouble seeing the start area. I guess either some big vehicle was parked in the way during heat 2 or that particular grid worker just needs some glasses.

2. The bus was so far from the finish that there was no way to confirm visually whether each car crossing the finish line was the one the time was being recorded for. If one car is missed at the start, or one doesn't physically break the finish beam, or an extra start or finish signal is captured, we're suddenly one car off without knowing it. This has been a problem in the past, several times since we started taking advantage of the new timing system's additional range, and I've complained about it enough. Nonetheless, anytime we locate the finish too far to see from the bus, the risk of a single, simple error causing downstream errors is increased significantly. Again, I'd sure prefer having the start far from the bus over the finish far from the bus. (Rant off)

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Keith Q.
2008 Top Gun
http://www.youtube.com/watch?v=KmX8XuZ_DCo&NR=1