Street Touring classes + TIR class?

JamesShort · **Posted:** Thu May 20, 2010 4:34 pm

JasonWatts wrote:

Keith Vail wrote:

But Jason you have the perfect NB to put 17's on because you have the 6 speed transmission so it will make your 2nd gear much more usable. I also know you can squeeze 17x9's and a 245 under your 10AE with rolled fenders. :twisted:

JasonWatts wrote:

I have been looking around in my spare "im bored time". There are two rim choicese that I am aware of that will give me, and dustin a wheel wide enough to squeese a 255 on.

However, as Ryan said, there dont really seem to be any street tires in the 255 range that fit a 15 in rim. (if only there was a way to "shrink" a tire a few inches. I have been told to wait for the hankook as they will be releasing a 255 something 15 soon... then again, soon was said several years ago. Maybe the STR class will give them the motive to push out a 255 and then other makers will hop on the band wagon.

and be looking at an acceleration rate of 1 mile per year? :lol:

I am at least a year away from any purchase to go in any direction. I have wondered if going to a larger rim will hurt me bad enough to not justify the wider tires.

I was reading a miata.net conversation (I think) about how NA/NB miatas are very sensitive to increases in weight (more importantly, rotational moment of inertia) of the wheel assemblies. And because of this going to larger/wider wheels and wider tires has a point that the increased lateral grip isn't worth the sacrifice in acceleration. I don't remember specific numbers though.

KendtEklund · **Joined:** Tue Mar 27, 2007 7:29 pm **Posts:** 1204

Dustin Fredrickson wrote:

michaelsmiller wrote:

Why do Miatas always get screwed?

One might say that that Miata drivers are used to taking it .... uh, nevermind.

And based on your car progression Dustin, it appears the most soothing treatment for that is Bimmerdouche? :lol:

Keith Vail · **Posted:** Thu May 20, 2010 5:00 pm

That is very true but many of the CSP guys found out that the 275/35/15 is faster than the 255/40/13 Hoosier unless it is cold out and the weight and circumference are very different between those two setups. I think some testing would be in order to truly find out which one is the faster setup on a 6 speed car. On a 5 speed car I would never even think about putting the 17 inch tires on it because you would have no acceleration whatsoever.

JamesShort wrote:

I was reading a miata.net conversation (I think) about how NA/NB miatas are very sensitive to increases in weight (more importantly, rotational moment of inertia) of the wheel assemblies. And because of this going to larger/wider wheels and wider tires has a point that the increased lateral grip isn't worth the sacrifice in acceleration. I don't remember specific numbers though.

JasonWatts · **Posted:** Thu May 20, 2010 6:40 pm

JamesShort wrote:

JasonWatts wrote:

Keith Vail wrote:

But Jason you have the perfect NB to put 17's on because you have the 6 speed transmission so it will make your 2nd gear much more usable. I also know you can squeeze 17x9's and a 245 under your 10AE with rolled fenders. :twisted:

JasonWatts wrote:

I have been looking around in my spare "im bored time". There are two rim choicese that I am aware of that will give me, and dustin a wheel wide enough to squeese a 255 on.

However, as Ryan said, there dont really seem to be any street tires in the 255 range that fit a 15 in rim. (if only there was a way to "shrink" a tire a few inches. I have been told to wait for the hankook as they will be releasing a 255 something 15 soon... then again, soon was said several years ago. Maybe the STR class will give them the motive to push out a 255 and then other makers will hop on the band wagon.

and be looking at an acceleration rate of 1 mile per year? :lol:

I am at least a year away from any purchase to go in any direction. I have wondered if going to a larger rim will hurt me bad enough to not justify the wider tires.

I was reading a miata.net conversation (I think) about how NA/NB miatas are very sensitive to increases in weight (more importantly, rotational moment of inertia) of the wheel assemblies. And because of this going to larger/wider wheels and wider tires has a point that the increased lateral grip isn't worth the sacrifice in acceleration. I don't remember specific numbers though.

James,

Do you remember what the thread was? if you do, it will give me something to read at work?

JamesShort · **Posted:** Thu May 20, 2010 7:08 pm

JasonWatts wrote:

JamesShort wrote:

JasonWatts wrote:

Keith Vail wrote:

But Jason you have the perfect NB to put 17's on because you have the 6 speed transmission so it will make your 2nd gear much more usable. I also know you can squeeze 17x9's and a 245 under your 10AE with rolled fenders. :twisted:

JasonWatts wrote:

I have been looking around in my spare "im bored time". There are two rim choicese that I am aware of that will give me, and dustin a wheel wide enough to squeese a 255 on.

However, as Ryan said, there dont really seem to be any street tires in the 255 range that fit a 15 in rim. (if only there was a way to "shrink" a tire a few inches. I have been told to wait for the hankook as they will be releasing a 255 something 15 soon... then again, soon was said several years ago. Maybe the STR class will give them the motive to push out a 255 and then other makers will hop on the band wagon.

and be looking at an acceleration rate of 1 mile per year? :lol:

I am at least a year away from any purchase to go in any direction. I have wondered if going to a larger rim will hurt me bad enough to not justify the wider tires.

I was reading a miata.net conversation (I think) about how NA/NB miatas are very sensitive to increases in weight (more importantly, rotational moment of inertia) of the wheel assemblies. And because of this going to larger/wider wheels and wider tires has a point that the increased lateral grip isn't worth the sacrifice in acceleration. I don't remember specific numbers though.

James,

Do you remember what the thread was? if you do, it will give me something to read at work?

Not sure if how to find it. Let me ask Patrick at work tomorrow.

JamesShort · **Posted:** Thu May 20, 2010 7:14 pm

Keith Vail wrote:

That is very true but many of the CSP guys found out that the 275/35/15 is faster than the 255/40/13 Hoosier unless it is cold out and the weight and circumference are very different between those two setups. I think some testing would be in order to truly find out which one is the faster setup on a 6 speed car. On a 5 speed car I would never even think about putting the 17 inch tires on it because you would have no acceleration whatsoever.

JamesShort wrote:

I was reading a miata.net conversation (I think) about how NA/NB miatas are very sensitive to increases in weight (more importantly, rotational moment of inertia) of the wheel assemblies. And because of this going to larger/wider wheels and wider tires has a point that the increased lateral grip isn't worth the sacrifice in acceleration. I don't remember specific numbers though.

That is interesting because the 275 is a good bit larger in circumference so the gearing is not great for a 5spd miata AND it is a good bit heavier. Are these 15" wheels absurdly light compared to whatever 13s you are referring to (couldn't image).

Are CSP miatas able to get a good bit more power than STS/STR miatas? Intake, header, exhaust, EM (timing/fuel) can't get much more than what, 25-35 whp (and likely in the higher revs) compared to stock. In fact (correct me if I'm wrong) there might not be a big difference in output between ST* and CSP miatas. Can you PnP intakes/heads/headers in *SP?

JamesMilko · **Posted:** Thu May 20, 2010 10:05 pm

JamesShort wrote:

Are CSP miatas able to get a good bit more power than STS/STR miatas? Intake, header, exhaust, EM (timing/fuel) can't get much more than what, 25-35 whp (and likely in the higher revs) compared to stock. In fact (correct me if I'm wrong) there might not be a big difference in output between ST* and CSP miatas. Can you PnP intakes/heads/headers in *SP?

You also get a 1mm overbore, I believe .01 head deck, intake/exhaust manifold is completely open, and i believe port matching to an extent. You can also swap engines so you can run a VVT engine in a NA. One of the national level CSP guys on miata.net has dynos up of his car running 160RWHP.

There is also CSP "weight reduction" through update/backdate. Can remove the soft top, swap in a 90-91 non airbag dash, remove AC/radio/power steering, replace seats with race seats, 1.6L brakes. I think that's the main points. I'm sure there is more that can come out in CSP but that's just what is on the top of my head.

SP also gets some aero. I'm not sure what ST gets there, if anything. 10" spoiler on the rear of the trunk lid and a front air dam.

Steven Carter · **Posted:** Thu May 20, 2010 10:16 pm

JamesMilko wrote:

JamesShort wrote:

Are CSP miatas able to get a good bit more power than STS/STR miatas? Intake, header, exhaust, EM (timing/fuel) can't get much more than what, 25-35 whp (and likely in the higher revs) compared to stock. In fact (correct me if I'm wrong) there might not be a big difference in output between ST* and CSP miatas. Can you PnP intakes/heads/headers in *SP?

You also get a 1mm overbore, I believe .01 head deck, intake/exhaust manifold is completely open, and i believe port matching to an extent. You can also swap engines so you can run a VVT engine in a NA. One of the national level CSP guys on miata.net has dynos up of his car running 160RWHP.

There is also CSP "weight reduction" through update/backdate. Can remove the soft top, swap in a 90-91 non airbag dash, remove AC/radio/power steering, replace seats with race seats, 1.6L brakes. I think that's the main points. I'm sure there is more that can come out in CSP but that's just what is on the top of my head.

SP also gets some aero. I'm not sure what ST gets there, if anything. 10" spoiler on the rear of the trunk lid and a front air dam.

Geez....has *SP always been like that? Seems like it's more of a "who has the bigger wallet?" class than previously. Those mods add up to serious coin for a full-prepped *SP car.

Donnie Barnes · **Posted:** Thu May 20, 2010 11:53 pm

Steven Carter wrote:

Geez....has *SP always been like that? Seems like it's more of a "who has the bigger wallet?" class than previously. Those mods add up to serious coin for a full-prepped *SP car.

SP has suffered some rules creep over the last ten years, sure. Partly due to trying to keep old cars competitive with newer ones, partly because guys just keep wanting to fab stuff.

It can be very expensive to fully prep an SP car these days. I'll bet Bill could find a few more ponies in that setup (and a better torque curve) with about $7500 in MoTeC, too. *shrug*

--Donnie

Chuck Branscomb · **Posted:** Fri May 21, 2010 6:42 am

Donnie Barnes wrote:

It can be very expensive to fully prep an SP car these days.

I remember when SP classing first appeared in the early 1980s and how happy many were that there was now some choice between stock and prepared (this was when there were three sets of classes: stock, prepared and modified). After being away from the sport for many years and returning in 2004, I was a bit shocked looking at fully rule-prepared SP cars these days.

I guess we'll next see SSP, semi-street-prepared classing.

JamesMilko · **Posted:** Fri May 21, 2010 8:06 am

I think it's funny how many "street" prepared rules allow a car to not be street legal. Airbag removal, ECU swap, long tube headers, etc Those 3 are all federal too, not state.

JamesShort · **Posted:** Fri May 21, 2010 9:05 am

A coworker of mine just put a new engine in his NB miata built by Long Road Racing and it dynoed at 160whp and all he has is intake/header/exhaust. But of course, due to the internal work, it is not CSP legal......SSM. Crazy to think that you can get that same power from CSP legal modifications.

jeremy gast · **Posted:** Fri May 21, 2010 12:21 pm

in "sp" they are starting to go with e85 fuel since is it "pump fuel" now. there are some interesting thread over on miata.net about the csp rules and money. here is what they are coming up with a REAL quick run down.

O.K., he's how I came up with my statement that to go fast in SP (compared to other classes) it isn't all that much.

SP Miata

Bogarts: $1,700.00
OS Giken diff.: $1,500.00
Hydra: $2,000.00
Race clutch: $1,500.00
Good shocks: $2,500.00
Tires: $1,100.00
Motor: $3,000.00 - includes. forged pistons
Delrin Bushings: $400.00 (make your own)
Dyno: $1,500.00 (this is over many years)
Seats: $500.00
Sway bar: $250.00
Aero: $300.00 (make your own)
UD/BD parts: $ 200.00
Car: $2,000.00-$7,000.00 (stripped NA - stripped NB)

Total: $18,450.00 - $23,450.00 depending on the price of the car

Also some of them including Bill Schneker is running the maxim works header that is $1100+
kinda makes you go "hmmmm"

jeremy gast · **Posted:** Fri May 21, 2010 12:22 pm

my 90 model didnt have a pass side air bag!!! so with update backdate is how they do it.

JamesMilko wrote:

I think it's funny how many "street" prepared rules allow a car to not be street legal. Airbag removal, ECU swap, long tube headers, etc Those 3 are all federal too, not state.

Carl Fisher · **Posted:** Fri May 28, 2010 11:17 pm

I just stumbled onto this thread, and although I haven't read it carefully, it looks like it has something to do with the prereg page. I assume, since no one has contacted webmaster, that there's nothing that needs to be changed.

If that's not the case would a VP or P please contact us.

Thanks.

THSCC Forums

Street Touring classes + TIR class?

Who is online