BNR S3 + Methanol = ??? (Awesomeness, I hope!)

For sure. It'll be ridiculous when the weather is cooler again, LOL. Without methanol as part of the picture, I've logged extensively and conclusively shown that power levels can easily sway on the order of 30/30 whp/wtq or more between the cold temps of winter, and the 100+ degree temps of summers we have, at least here in north Texas. Ambient conditions have a very significant impact on our power levels.

 

70,xxx compression test today, post spraying several gallons of 100% methanol with my CM10 (12.8GPH) new nozzle. Surprising and AMAZING results!
http://mazdaspeeds.org/index.php?threads/methanol-to-restore-compression-d.3379/

Pics of plugs (1 to 4, left to right):

(Oil at bases was likely due to the oil overfill, or my new VC gasket needing tightened. Cleaned up plugs and tightened down VC to ensure no oil seepage up there. I'll keep an eye on it.)


(Engine clearly still loves step-colder NGK IX iridiums. Gap opened up from 0.026" to these numbers. Re-gapped back to 0.026", cleaned up plugs to keep an eye on the oil nearest insulator side, and re-installed.)

I also ran some checkup logs and got the car washed before doing the compression test (basically how I got everything fully up to temp). I had some unexpected results:

(While it's great to see that I'm still making ~385whp @ redline with 73-degree IATs and that I still have zero KR beside the characteristic initial throttle tip-in range, one thing is clear: my clutch is starting to give up on life... see the attached datalogs)


Looks like it's time to make a new thread... http://mazdaspeeds.org/index.php?threads/which-clutch-should-i-get.3380/#post-27396

 

So my last update had me scared that a new clutch was needed imminently. Buuuuuuut..... it may no longer be an issue, thanks to @Enki. I followed his advice about downshifting to raise the revs while coming up to a stop light and pressing the clutch so that it slightly engaged and reverse-scrubbed off any glazing that may be a factor. Results?

73 IAT
Log 1: 4.64 60-100; BATs plummeted to 59 in the middle of the pull and rose up to 62 @ redline (still 10 degrees below IAT)
Log 2: 4.66 60-100; BATs plummeted to 61 in the middle of the pull and rose up to 64 @ redline (still 10 degrees below IAT)

I really, really appreciate you, James. If nothing else, it looks like I've at least extended my clutch life. Oh, and IDCs were ~88. Did I mention I love my CM10? And with my increased compression due to methanol cleaning, my power numbers in the 70s are like they used to be in the 40s or below o.0

Logs attached...

 

i've been noticing my revs climbing while trying to accelerate in higher gears for some time now. it happens very randomly and i assume it's the clutch. i even sent Justin a log of exactly what you have, and he mentioned it looks like clutch slip.

what is this magical trick you speak of "reverse scrubbing" of the glazing. i always downshift when rolling to a light or stop sign. are you (& @Enki; ) suggesting that after i downshift, and the rpm's rise, to press the clutch slightly to barely engage in order for the reverse scrubbing to occur? gonna have to try this on the way home.

 

Slip the clutch when engine braking; go clutch in, downshift, then ease the clutch out until the rpms start to climb and hold it there so the clutch slips backwards.

 

I seriously doubt that that will help @Enki. I tried that shit for weeks with my car (didn't even go WOT, just drove normally, dumped/slipped clutch under engine braking to try to "deglaze" the clutch). Then I took this vdyno:



And yet it would never slip on 93, not even once. When we pulled my clutch we found nothing major wrong with it. Over half the friction disc was remaining and there were no major hot spots on the pressure plate or flywheel. The stock clutch just cannot reliably hold more than ~360 wtq or so IMO. Even if you can play with it to get it to hook again, what is the point? The conditions that led to it slipping like this to begin with are obviously extremely easy to create. He already has the clutch kit, so remove the weakness the stock clutch represents at this point and never worry about it slipping again.

 

Mine held ~390 WTQ (1.01 SM3) after being glazed to the point where normal acceleration was fucked...Twice...Within 80k miles.

 

Your car is also many years older than both of ours. Small variations in the construction materials/processes of the friction disc or other components could easily yield slightly different torque capacities. For example ever notice how genpu cars have lighter clutch pedal feel than juans even in juans utilizing the pu slave cylinder?

 

True, but it can't hurt to try. Got a buddy of mine running stock clutch who's putting down 390 ish in his pu.

 

Before/After @Enki and @VTMongoose:

Yellow and green are obviously before. Red and blue are after. And wouldn't you know it, identical IAT (73 degrees) on both days, so that variable is controlled. I supposed I may still slip when it's colder. I'd have to take more logs to find out. But so far, my problem is completely resolved.

I did Enki's trick for ~1-1.5 weeks, then took it easy on the car for another 3 weeks. I also began downshifting/engine braking when coming up to reds instead of coasting in neutral. Results speak for themselves (or at least I'm one of the lucky ones).

Regardless, I have a Southbend Stage 3 Endurance and all the support parts ready to go in as soon as needed.
[doublepost=1483666775][/doublepost]Here's a good way of explaining the same process I used, just worded a little differently, so it may make more sense to you than it did initially to me (@Enki and I had a laugh because I was doing it wrong and actually glazing my clutch more! o.0):

Reverse grinding the clutch:
1. Get speed up to 35 miles per hour
2. Put transmission into 2nd gear and let rpms rest down to idle
3. lightly engauge clutch until RPMs start to rise.
4. hold rpms steady at about 1200-1300rpms for 10 seconds (or as long as possible - I usually got a solid 3-5 seconds - modulating my clutch is a little tricky).

Like I said, I did this at every stop light for like a week. And I'd usually do it in both 3rd and 2nd while slowing down, especially if I was starting at 50mph or so.

 

cool. i engine brake almost every stop. i started doing exactly how you explained yesterday. i'll keep it up for "research purposes". but damn, my car (an '08) is only around 300hp / 320 tq., on e33. gonna need a clutch soon.

 

Why? Stock clutch is rated for ~365lb/ft, but can often handle a lot more (underrated). Has someone been slipping your clutch a lot, or maybe it's just really old/lots of miles?

 

not sure really. i bought the car 3 years ago with 42k on the clock. i've put 30k on since, so the car is at 72k miles. not sure if a kid owned it before me or what. just started happening over the summer.

i tried this "reverse scrubbing" technique over the weekend and can't really get it to work. i had justin set my rpm's to 900, and can't seem to get the rpm's to rise after engine braking close to idle. i'm probably doing more damage than anything.

 

Not sure how you're doing it. Try this:
1. Get to 50 mph.
2. Downshift to 2nd and keep holding in the clutch so that rpms settle down to idle (the car will naturally be losing speed as you wait to get close to idle)
3. When you're close to idle, maybe ~1,100-1,200 rpms, then slowly let out the clutch until it starts engaging - prolong this state as long as you can.
4. If you do it right, the car will start slowing down a lot faster because you'll be starting to engine brake as the tranny begins engaging the engine through the clutch.
5. You can do this at higher speeds in 3rd too, like getting off an exit ramp when going 70 or so.
6. When coming up to redlights and not doing this, downshift gears and engine brake as you roll up to the light. Depending on the speed at which you start, this may just be a single downshift, or a couple.
7. Do this for at least a week. And try not to do it too many times in a row. You don't want to overheat anything.
Hope this helps...

 

thanks bud, i haven't been holding in the clutch. i've been engine braking with the clutch out, then i slightly press it in once it gets close to idle. i'll try as you mentioned.

also, sorry for thread jacking. but i do plan on an s3 down the road if that matters.

 

Yeah that wasn't slipping the clutch at all then. You basically didn't do anything to resurface the clutch, really.

 

I tried the trick on my stock clutch, didn't work, but could be because of being way above the limits of it anyways (plus the disc had over 200k miles lol)

 

Every time I've done it, I've done it every day over the course of a week or so and gradually increased the application of power to see if it would hold. How long did you try?

 

Once a day for a week and no wot for 2 weeks or so before I tried to wot again (it rains too much in Ohio during the summer).

 

I guess my thread has become the clutch deglazing thread, LOL
Well, I suppose that's okay for now. Heck, if it can save others thousands of $$$ too, that's a good thing.
I look forward to doing more on-topic updates before too long, but not much has changed recently. Just driving/enjoying the heck out of my Speed.