0-60 - having a hard time
 

I put on my new FM dual exhaust and had an opportunity to go out driving for a little while so i wen to the nearest highway to do some on-ramp zero to 60 runs while datalogging.

Maybe the connection is in my head, but ever since I had my new clutch put in, i'm having a hard time doing a quick 1->2 shift. It's almost like the gate is blocked at high RPMs, i just can't jam the stick in there..

If shifting nice and slow at 4k rpm, i have no problems.. it's just when i floor it in 1st then try to shif quick into 2nd to get to 60, i feel locked out.. sometimes I get half-way in then end up grinding gears as I let off the clutch?!

It's kinda frustrating that the car feels pretty quick in the higher RPMs now, but can't make good use of it because i have to shift so slowly and deliberately.

Same exact issue for me....your tranny is fucked just like mine :giggle:

The number one reason you get blocked out of gears is an improperly adjusted clutch, which creates clutch drag. Make sure your clutch is adjusted correctly before you get too scared about a bad trans, although if it's been dragging for some time the damage may have been done.

To test for drag, place the car on level ground with the e-brake off and make sure the car won't roll forward/backward under gravity. Put the car in 1st gear, depress the clutch all the way, and rev the motor to 6500+rpms. If the car creeps forward with the clutch depressed, then it's dragging.

Another reason for clutch drag is related to the type of disc used. Sprung-hub street discs are the worst, solid hub puck-style are better, and twin discs are the best for avoiding it.

Matthew, thanks for the tip. I'll give that a shot tomorrow.

The new clutch does engage very close to the ground. I mentioned this to the mechanic who did the job (and also owns a miata), he said it's not adjustable. I know you can adjust the free-play on the pedal, but is there something else that you're referring to?

cspence - i hope you're wrong about the tranny being shot!! My budget's tapped for the year :)

-Tomaj

The clutch IS adjustable. Find a mechanic with a clue, or failing that, do your own research.

http://www.miata.net/garage/adjust_clutch/index.html

If you want to shift with speed, make it shift at the top of the travel.

In my previous post I mentioned i was aware that the clutch pedal is adjustable (that's what your link describes). I was wondering if there's some OTHER adjustment i'm not aware of..

My issue is that there's already not that much free play in the pedal. I can try to adjust it a litle bit but i dont want to risk effectively riding the clutch all the time either by placing the pedal under tension (technicall compression?) even when all the way out.

-Tomaj

Adjust so that there's just a tiny bit of freeplay, then.

Really? From the link you just quoted back to me:

"And that's it! Just tighten up the bolt that stops the shaft from moving, and take the car for a drive! Then repeat until the engagement point you want is reached!"

Engagement point =! Freeplay

"P.S - Mad Swede from miata.net pointed out that i missed a few things. First off, when you are adjusting the pedal, you must check the freeplay. when you are adjusting it, it changes the "dead zone", where you can push the pedal without much resistance. while you are adjusting it, you want the freeplay to be around .2 to .5 inches. Also, when you finally tighten the nut, you must make sure the rod doesent turn. Mad Swede said he used a dot of whiteout on the rod so he could check if it moved, which is a also good idea."

Freeplay should ALSO be considered. If you'd actually read the link before throwing it back to me, you'd know that you can change the engagement point, and therefore the amount of connection between clutch and flywheel with the clutch in and out.

@Nagase, chill out. :hustler:

Coming from the world of DSMs here, but our slave cylinders are self-adjusting and there is a bleeder valve in the master to make that work. If the master is improperly adjusted then that valve can be blocked off and won't allow for full clutch fork travel. I can post up a DSM-based adjustment video if you would like, which shows the adjustment of the hydraulic system. If the Miata systems are set up this way you could give it a shot.

You do realize that you have to lift while shifting, to allow the synchros to catch up?

Alik, i depress the clutch, shift from 1 to 2, then lift clutch. I believe you're referring to double clutching, which i do not do when upshipfting.

Anyway, i gave the clutch adjustment a try. I already only had around a quarter inch of free-play, so I actually backed off the 'stop' switch to give me more free-play, then i extended the push-rod as described in the linked article.

I drove the car and clutch takeup seemed to be a little higher. Didn't attempt a full throttle 1st to 2nd shift as i was local in town and the car's a little loud, likely to attract unwanted attention.

-Tomaj

Tomaj, try to follow me.
Full throttle acceleration in 1st, lift off throttle, while simultaneously push in the clutch pedal, shift, step on the gas.

Lololololol! Sorry, I just had to quote that:laugh:

Any who, Nagase and Sav are right. It just takes some adjustments, which you can do yourself.

When I swapped out my clutch last year, I went with some thing more beefy for straightline racing and it took me a good week or two to get the clutch engagement right where I wanted it.

However, the worst thing you can do it get upset with it and start to tear stuff up. So calm down with the fast&furious shifting and get your car properly set the way you want. It will be alot cheaper than a new clutch or trans:giggle:

Best of luck to you!

Alik, does it make you feel good to talk tough on internet forums? Your previous post, to me, seemed to refer to the clutch, not the gas. And yes, I do lift off the gas while shifting, otherise i'd no doubt be bouncing off the rev limiter..


@viperormiata - thanks for the note. I've had this clutch in for several hundred miles. I didn't just get it in and start doing full throttle launches :) Regarding the trans, i may need a new one anyway, mine whines in 1st and 2nd gear a little, may be related to my shifting problems too..

-Tomaj

Hey ctxspy, does it make you feel good to mock the people who are helping you? :hustler:

Tomaj, you're right. I'm sorry.

Here's a solution to your issue.

Get a membership to Gold's Gym. Pump some iron. Develop bigger pecks, so, you can slam the fucking stick in the POS gate.
I mean, after all, if the bitch doesn't wanna follow what you tell it to, why not FORCE the issue?
(Btw, dunno if anyone informed you, but, a little nudge does wonders to improve the function of your synchros. )

Alik, Nagase, please put me on your ignore list and i'll do the same. :makeout:

You guys both came in here with a condescending & rude disposition.
Please contrast your posts to those of Braineack, Joe Perez, and (in this thread specifically), viperormiata & matthewsdesign..

To the other guys -- i'll post back as soon as i had a chance to test out the changes i made last night.

You mean something like this?

Cool!
Lemme try!

Dear morons!
Manual gearbox in performance driving conditions necessitates, if not requires double-clutching.

Love, "The Jerk"


Al did good?

lol @ this thread.

to whoever suggested adjusting the engagement though: THANK you. Ever since I installed my ACT its been engaging way too early. Not to the point of stopping me from shifting, but enough to have to depress teh pedal all teh way to the floor.

I'll try adjusting the rod today

That's right, I said ROD:giggle: