spec miata

Zoo....The early 90 - 91 Miatas had a crank with a short nose. When the crank pulley is assembled on the cranknose, if the woodruff key was installed upside down it wouldn't seat in the cranknose all the way, after a short while is would come loose then brake and cause havoc on the crank and who knows what else. As long as that Woodruff key is installed rightside up and some locktite for added insurance is used there is nothing to worry about. Other than that, if the car drives out ok & is in good condition you should be all right, these cars are rock solid, and a blast to drive on & off the track.

Here's a few titles of books that are a must own for Miata enthusiast: Mazda Miata Performance Handbook, By Norman H. Garrett III, MBI Publishing, ISBN 0-7603-0437-8, & Rod's Mazda Miata Enthusiast's Shop Manual, By Rod Grainger & Pete Shoemark, Veloce Publishing, ISBN 1-874105-59-6 (US edition softback).

Good luck & Have fun!

David #27
Hawaiian Shirt Racing

Damn! 8 SM's in Des Moines, we'll be having 20+ car fields at Gateway this year, along with the Blues bar hopping in Soulard on Saturday night.
 
Thanks for the tips ! I will buy the books. Need all the info I can get.
Funny you mention 20 car SM races, because at moroso there were 20 ! Largest feild the whole race weekend.
 
I predict, here in the NE, that we will see 25 or 30 cars easily, and I wouldn't be surprised if the fields are larger not only here but all over the country. I bet some areas will dedicate a whole run group to them.

I also be that we start seeing the Miata as a contender in ITA on certain tracks.

------------------
Jake Gulick
CarriageHouse Motorsports
ITA 57 RX-7
New England Region
[email protected]
 
Zooracer: Check miata.net for advice on what to watch for. Specifically:

Crankshaft stuff: http://www.miata.net/garage/crankshaft.html
http://www.miataclub.org/orlando/xnosecrank/

Buying a used Miata:
http://www.miata.net/faq/usedmx5.html


Jake: Midwest Division was a little slow on the uptake for Spec Miata: we've just finished season #2 with SM, and are beginning season #3. Biggest group of SMs I was in last year was the very last race at Gateway - 11. We'll get there.
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Jarrod
 
Thanks Jarrod for the sites on crank problems for 90 miata's. I does worry me now, as it seems like it is an issue of when not if the crank will fail.
I would rather not have to find a 92 or later motor when the crank fails. Of course, if this happens years down the road, no big deal, but if it goes in a few months I would be highly disappointed. I dont consider myself skilled enough to swap cranks.
Should I risk it ? I know I can look at the pulley while it is running to look for a wobble. Starting to wonder now about buying this car.
Also, I read that the factory viscous LSD will wear out and when it comes time to replace with the Mazda Motorsport one it will be more expensive because it requires different axles. Is this true ?

[This message has been edited by zooracer (edited January 14, 2003).]
 
Originally posted by zooracer:
it seems like it is an issue of when not if the crank will fail.
I would rather not have to find a 92 or later motor when the crank fails. Of course, if this happens years down the road, no big deal, but if it goes in a few months I would be highly disappointed. I dont consider myself skilled enough to swap cranks.
Click to expand...

A little story for you: my '91 has 165,000 miles on it. I bought it a year ago as a street car and converted it. I didn't touch the motor (except for an oil change and new plugs). It ran 10 races and 3 schools, along with several autocrosses, this past summer. Still runs. (Leakdown showed 24% in one cylinder when I pulled it last weekend).

As long as you properly maintain the end of the crank, you'll be fine. Get a new bolt and a new key (grand total of about $10 in parts), take the old parts out and put the new parts in according to the service manual. Torque the bolt correctly, with Loctite on it, and you'll be fine.

Or buy a crate motor for (now) about $2k shippped.
wink.gif


Also, I read that the factory viscous LSD will wear out and when it comes time to replace with the Mazda Motorsport one it will be more expensive because it requires different axles. Is this true ?
Click to expand...

True. You need to buy stub axles. 2 at $66 apiece. Factor in the $528 for the Comp limited slip plus install, it's not that much.....

David does have a good point - head to www.specmiata.com and use the search function there, and you'll learn more than you EVER wanted to know....

Jarrod


[This message has been edited by JIgou (edited January 15, 2003).]
 
I had the feeling someone was going to complain about a spec miata discussion on an improved touring forum. I did actually try to register with the spec miata forum last night to ask the questions but was unsuccessful. When you register they dont ask for a password, but then when you try to post on the forum they require one.
Anyways, I am not definite on going with spec miata. I could still decide to make it an ITA car. Or, I may decide just to race my 89 suzuki swift GT in ITB, where I think it would win championships (100hp/1700lbs).
If that makes anyone feel better about my posts on here, ha ha.
Seriously, you guys have been a huge help. It would be much more difficult to learn about this stuff without this forum, thanks again.
Oh, you mentioned having so many miles on your 91 with no problems. I think the short nose was discontinued in 91 sometime. Did you actually have the short nose crank ? (note to moderator: this question could still apply to improved touring, heh heh)

[This message has been edited by zooracer (edited January 15, 2003).]

[This message has been edited by zooracer (edited January 15, 2003).]
 
zooracer, I am not suggesting that you go away. The suggestion was made in a manner meaning that you could do a search & also that on SM site you might get several different responses to your Miata questions.

Sitck around
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David
 
I know you werent trying to get rid of me.
I was just joking. I am probably going to concentrate on the suzuki right now, I think two cars would be a handful.
I would love nothing more than to beat all those volvos and VW's with my suzuki.
I may still get a miata, and when I do I will return to this section of the forum. Once again, thanks for everyones help.
 
The failure of the early (1990 to mid '91, see www.miatanet.com for details) crank is usually caused by servicing the timing belt and reinstalling the pulley key backwards. It is an easy mistake to make (ask the dealership mechanic who did it on my '90), and generally speaking is the sole cause of the failure.

A later crank apparently does not fit in the earlier motor, so either replacement of the OE crank with the same part is required, or replacement of the entire motor is indicated, which is why my street/race car has 250K on the chassis and about 225K on the '92 motor in it now.
 
True, and you can repair this problem by having a mahine shop cut a new keyway 180 degrees from the old one.

This was also a problem in some early model Audis.

I doubt a double keyed crank is legal, but someone may be able to figure something out.
 
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