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well i ordered some crystals from digikey, got raped on shipping and handling, so i ordered extra's to spread the love. i ordered 10 - 4.4mhz crystals, 5 - 4.9 and 5 -5.06 crystals. $2 make you holler. I will mail them to your house...
the 4.4 raise the rev limit 10%(7600), 4.9/5.0 raise it 20% (effectivley eliminating it)
http://forum.miata.net/vb/showthread.php?t=145076
here is the thread on m.net discussing...
Chris
Chris,
I have a professional soldering station at home that can do surface mount too... If you need someone to replace the crystal for you, just holler.
Also, Tanner's over in Carrollton or Mouser (www.mouser.com) may be easier than Digi-Key or other places. Mouser has a warehouse down in Mansfield so the parts get to you VERY quick.
RJ
Very interesting thread. I may have to try this....for testing use only.......of course! ;)
I'd be all over that if I wasn't in E-stock. :cat:
I guess this means they'll need to pop a scanner on the OBD-II Spec cars to see if they can communicate with 'em... It sounds like another method to cheat.
RJ
You are such a :cat: ! :razz:Quote:
Originally Posted by Miatamoto
So how many more RPM could you spin the motor safely before you move into the motor of the month club??
Well I installed the 4.43 crystal in my 00 and it bumped the redline to about 7700-7800. I can get to about 62-63mph in second gear now...
I couldnt wait till friday, so I went by Tanner Electronics and picked up a couple of crystals. Thanks for the heads up on mouser.com! I'm always soldering something...
Chris
I get what the crystal does, but my question is how fast can you spin the motor before you could encounter catastrophic consequences?Quote:
Originally Posted by Kags1969
http://red4est.red4est.com/miata/pis.../PICT2823N.jpg
Well odds are that the engineers at Mazda built a "safety cushion" for the engine with the current red line.... I like to think of this as trimming the safety cushion. Some people like more cushion, I guess you could put a 3.8mhz crystal in and lower your redline.... :wheelcha: :burnrubr:
Anyone know if this is CSP legal? I could see it being an advantage on some courses where you are right on the edge of getting into 3rd gear. There was a thread about this on the :batman: board a week or so ago.
Yes. Rev limit is free in SP.Quote:
Originally Posted by Majik
Loren speaks like a mad man, This surely got my interest.
Way back in the early 90's, after the short nose crank was fixed, Miata Mag said the bottom end was good for 8000RPM. I believe 'em............ :)Quote:
Originally Posted by Kags1969
The saying "tinker till it blows, then back it off a notch" comes to mind. Now we just need a volunteer....
Hey Bean... we need to "inspect" your ECU. :pirat:
I think we should stick with Kags' ECU... he's done plenty of experimenting for the rest of us! ;)Quote:
Originally Posted by Titus
Although if it really works I wouldn't mind doing it.
While Kags is the man when it comes to testing lubrication limits, this test is really about wiring. You are the wiring harness expert. We need you to do some soldering for the better good of all Miatafiles. :viking:Quote:
Originally Posted by Treibenschnell
I pulled the ecu last night and put a switch with a stock 4.0 crystal and a 4.43 crystal in, and can swap back and forth with the toggle switch. Figured this was a good idea, b/c of smog and such.
Chris
Fine... I'll be a sucker. OK Kags, my ECU is next.
For TCB, you can always solder some single socket pins in the board and plug the crystal in... ;)
That way you can put a small hole in the top cover & change out the crystals at will... and play around with lots of different values.
RJ
Not sure if I want to try this one. I'm already a member of the motor a year club!Quote:
Originally Posted by POS Racing
Motor #1 - short nose crank failure
Motor #2 - flash flood = water in cylinders then crack
Of course the last time I was at Hallet and MSR, I could've used a few extra rpm just to stay off the rev limiter.
Wouldn't be the bottom end that would worry me. I'd be more worried about floating a valve on the top end...Quote:
Originally Posted by MadMerv
That said, Tommy Reynolds on the pointy board did something similar to his CSP '99 a year or two back (moved the limit to a real 7800rpm, iirc), and has had no problems with it that I've heard of. There are others, as well. Andy Hollis did muck up the head on his CSP Miata by overrevving it, but I think his redline was set well above 8000rpm.
I think this would be useful for the occasional few extra hundred rpm at an autocross, but I don't know that I'd make a habit of running it up to 8k on every shift at the track without beefing up the valvetrain.
Where's Flyin96M in this topic? He was telling me about the rev limits before you float the valves and stuff when he was getting the stuff together for this 99 head swap. I think Merv is right; you can rev close to 8k before floating a valve but don't take my word on it.
Garzilla did the RPM mod on my '96 and '99 and it works great. Thanks Chris. Yesterday we took a picture of the tachometer and speedometer showing 8000 RPM and 65 MPH in second gear on the '96. Engine felt strong with our TDR prototype intake and header we are developing all the way to 8000 RPM. Did not notice any valve floating. This engine setup continues to pull hard at high RPM. Our '99 has the AFR gauge and we noticed the stock ECU after a couple of cycles pulled the fuel management right in line. It works.
Good and quick way to take advantage of more RPM.
Gary
Is this an NA development '99, or were you using the stock ECU in the Track Dog?Quote:
Originally Posted by shuhart1
I'd be curious to see dyno plots on a naturally aspirated '99 with this mod and typical bolt-on mods (intake, header, and exhaust). Might make for a nice, budget CSP engine setup.
I suspect both... the Track Dog was running NA as a dyno test mule for different NA I/H/E parts the last time I saw it.Quote:
Originally Posted by altiain
Iain,
Both cars are stock blocks right now. The '99 is getting her engine back in next week so we can put the blower back on. We are looking into our prototype intake setup for production, but we want to dyno test first to make sure the dyno butt isn't lying. Our prototype header compared to the JR and the Racing Beat produced the most power and torque. We are making finishing touches on the collector and soon to be in production. We hope to have it ready for Christmas.
Gary