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Howdy,

Mugenlude:

Andy- Any worries of the crank pulley not being balanced after to shaved the 2nd groove off it?  I've considered do this to my extra crank pulley, but I was worried about an unbalanced crank pulley.

As long as the area you're cutting off is evenly distributed around the circle (vs. there being a balancing weight or holes drilled or something), balance shouldn't be affected.

In my experience pulleys like this, both factory and aftermarket, are balanced 'naturally' so as long as you remove material equally, they'll remain balanced.  The flywheel and the crank are another story altogether of course.

Mark

marka:

Howdy,

Mugenlude:

Andy- Any worries of the crank pulley not being balanced after to shaved the 2nd groove off it?  I've considered do this to my extra crank pulley, but I was worried about an unbalanced crank pulley.

As long as the area you're cutting off is evenly distributed around the circle (vs. there being a balancing weight or holes drilled or something), balance shouldn't be affected.

In my experience pulleys like this, both factory and aftermarket, are balanced 'naturally' so as long as you remove material equally, they'll remain balanced.  The flywheel and the crank are another story altogether of course.

Mark

What he said.

--Andy

^^^ Sounds good, thanks guys.

---

Jason Frank
Bridgestone / datatoys.com / Redshift Motorsports STS Civic Si

TeamUndercoatRacing.com

Next installment is up with write-up on Peru Tour and Pro Solo.  Enjoy!

http://grassrootsmotorsports.com/news/category/project-cars/other-cool-cars-hanging-around-the-grm-office/1992-miata-sts2-project/

--Andy

Andy,

I want to lower my miata. What do you think is the min shock travel needed?

I am running #700 front springs and #325 rear springs with small after market sway bars front and rear.

Thanks

Robert Jones

STS2 Miata

rjones:

Andy,

I want to lower my miata. What do you think is the min shock travel needed?

I am running #700 front springs and #325 rear springs with small after market sway bars front and rear.

Thanks

Robert Jones

STS2 Miata

It depends totally on the sites you run at, with bumps and grip level both being important.

The easiest thing to do is get a conservative starting point, then use zip ties on the shock shafts as a tell-tale for shock travel used.  Take some runs and see how much travel is left unused.  You can safely lower them whatever amount is unused (minus a little bit of fudge).

--Andy

Andy Hollis:

rjones:

Andy,

I want to lower my miata. What do you think is the min shock travel needed?

I am running #700 front springs and #325 rear springs with small after market sway bars front and rear.

Thanks

Robert Jones

STS2 Miata

It depends totally on the sites you run at, with bumps and grip level both being important.

The easiest thing to do is get a conservative starting point, then use zip ties on the shock shafts as a tell-tale for shock travel used.  Take some runs and see how much travel is left unused.  You can safely lower them whatever amount is unused (minus a little bit of fudge).

--Andy

Andy, I co-drive with Robert 2 weekends ago out at mineral wells.  It was my first time autocrossing a miata so I don't have much to reference.  But I do believe the car felt wonderfully balanced and had only a hint of understeer (which was probably my own fault).

Robert has all the right pieces and seems well dialed in, but I believe there could be more grip attained in the front.  Are his rates too stiff for the 205/40/16 combo?

What would you suggest in obtaining more front end "bite"?

---

Jeremy Foley
2001 Subaru 2.5RS Retired G-Stock Autocross Beast
2003 Evo 8 Modded Daily Driver
2004 RX-8 Current Borrowed B-Stock Killer

President
Team if you can't beat them-Join them!

ratt_finkel:

Andy Hollis:

rjones:

Andy,

I want to lower my miata. What do you think is the min shock travel needed?

I am running #700 front springs and #325 rear springs with small after market sway bars front and rear.

Thanks

Robert Jones

STS2 Miata

It depends totally on the sites you run at, with bumps and grip level both being important.

The easiest thing to do is get a conservative starting point, then use zip ties on the shock shafts as a tell-tale for shock travel used.  Take some runs and see how much travel is left unused.  You can safely lower them whatever amount is unused (minus a little bit of fudge).

--Andy

Andy, I co-drive with Robert 2 weekends ago out at mineral wells.  It was my first time autocrossing a miata so I don't have much to reference.  But I do believe the car felt wonderfully balanced and had only a hint of understeer (which was probably my own fault).

Robert has all the right pieces and seems well dialed in, but I believe there could be more grip attained in the front.  Are his rates too stiff for the 205/40/16 combo?

What would you suggest in obtaining more front end "bite"?

Less front spring or more rear spring.  I run 700/450.

The alignment may also yield some improvement if the camber angles are too small.  Also, the cars seems to like a lot of front toe-out.

--Andy

Andy Hollis:

ratt_finkel:

Andy Hollis:

rjones:

Andy,

I want to lower my miata. What do you think is the min shock travel needed?

I am running #700 front springs and #325 rear springs with small after market sway bars front and rear.

Thanks

Robert Jones

STS2 Miata

It depends totally on the sites you run at, with bumps and grip level both being important.

The easiest thing to do is get a conservative starting point, then use zip ties on the shock shafts as a tell-tale for shock travel used.  Take some runs and see how much travel is left unused.  You can safely lower them whatever amount is unused (minus a little bit of fudge).

--Andy

Andy, I co-drive with Robert 2 weekends ago out at mineral wells.  It was my first time autocrossing a miata so I don't have much to reference.  But I do believe the car felt wonderfully balanced and had only a hint of understeer (which was probably my own fault).

Robert has all the right pieces and seems well dialed in, but I believe there could be more grip attained in the front.  Are his rates too stiff for the 205/40/16 combo?

What would you suggest in obtaining more front end "bite"?

Less front spring or more rear spring.  I run 700/450.

The alignment may also yield some improvement if the camber angles are too small.  Also, the cars seems to like a lot of front toe-out.

--Andy

Hmmm, the car was pretty lose as it is.  I'm not sure if Robert has tried higher rear rates, but I'm sure it's worth a shot.

If I remember correctly, he's running -2.5 degrees front,  either -2.5 or -2.75 rear.  With 1/4" toe out in the front.

---

Jeremy Foley
2001 Subaru 2.5RS Retired G-Stock Autocross Beast
2003 Evo 8 Modded Daily Driver
2004 RX-8 Current Borrowed B-Stock Killer

President
Team if you can't beat them-Join them!

Thanks Andy,

I may try higer rear spring rates.  Is their an advantage to running higher spring rates with a softer sway bar versus lighter springs and larger sway bar? I am running around -2.5 camber at both ends.

Robert Jones

More bar = less droop travel on inside wheel. When on drive wheels = more chance for inside wheel spin

More spring = harsher over bumps.

 

You have to find a balance between the two. There is no one set way for any car.

---

Nick Jackson
04 S2000 - BHP Brakes
71 240z w/some stuff

Andy,

Got any updates to the GRM series coming anytime soon?  Looks like you've had some very good results, would be interesting to see more of your thoughts on between (and during) event changes.

--Kevin H.

---

2000 Impreza RS STX/rallycross

rjones:

Andy,

I want to lower my miata. What do you think is the min shock travel needed?

I am running #700 front springs and #325 rear springs with small after market sway bars front and rear.

Thanks

Robert Jones

STS2 Miata

 

Your spring rates (and Andy's) are close to the old DP cars rates.  I used around 1.25 to 1.5" bump travel at the rear shocks - 1" maybe somewhere smooth like HPT.   That gives you 1.5-2" bump at the wheels. 

Thanks for the feedback SirNick and Stan.  Does anybody have an opinion on changing the clock crystal in the ECU to raise the rev limiter?

Robert

Andy Hollis:

Next installment is up with write-up on Peru Tour and Pro Solo.  Enjoy!

http://grassrootsmotorsports.com/news/category/project-cars/other-cool-cars-hanging-around-the-grm-office/1992-miata-sts2-project/

--Andy

 

Nice driving, Andy

I have a question regarding your shock failure -- do you use the sprung mass or unsprung mass to tie the car down on the trailer?  I'm also curious as to any reasons that Lee or Jay had to offer concerning the failure.

---

- Wes 2000 Contour SVT (CP 3L powah) 1995 Miata (CSP, finally on sticky tires)

Andy,

 You wont believe what hapened,

During the drive hom,e to Milwaukee,( after nationals) the motor let loose in Iowa City.  I dont really know what the problem is yet but the motor would barely run.  Luckuly Jason Frank was there to bail me out of a jam and we loaded the miata onto his trailer for the rest of the ride home. ( I own him lots of beer)  The next day the car wont even start, and only cranks.  When it cranks now, im getting a terrible knock from the motor.  So I guess I may be in the market for a new motor.  Anybody got any deal on a 1.6 liter with a long nose crank?

 Andrew Canak 

---

Andrew Canak

Hey Andy, didn't the SCCA change the name from Solo II to Solo a few years back? Old habits die hard, I guess.

---

I need a stupidity filter for the internet!

BigJon:

Hey Andy, didn't the SCCA change the name from Solo II to Solo a few years back? Old habits die hard, I guess.

Actually I believe it was just this year.

I could be wrong though.

---

Bridgette
#83 STS2 Miata
Powered by eBay
Roxie dog approved!

weargle:

Andy Hollis:

Next installment is up with write-up on Peru Tour and Pro Solo.  Enjoy!

http://grassrootsmotorsports.com/news/category/project-cars/other-cool-cars-hanging-around-the-grm-office/1992-miata-sts2-project/

--Andy

 

Nice driving, Andy

I have a question regarding your shock failure -- do you use the sprung mass or unsprung mass to tie the car down on the trailer?  I'm also curious as to any reasons that Lee or Jay had to offer concerning the failure.

Just saw this...

I tie the car down via the factory tow hooks and do so pretty snugly.  So it moves some, but not nearly as much as it might were it tied down by the wheels.

Jay/Lee said that there was a nick in the inside of one of the shock bodies.  Probably during a previous rebuild but who knows?  I'll be needing a new body for that one... 

 
--Andy 

Latest update is up.  This one is on balancing streetability and competitiveness.  Yes, you can have your cake and eat it, too.  But only if you are careful.  Enjoy!

http://grassrootsmotorsports.com/news/category/project-cars/other-cool-cars-hanging-around-the-grm-office/1992-miata-sts2-project/ 

--Andy