SM vs. ITA Miata

[joeracerx95]

I'm thinking about moving into ITA. One of the reasons SM is not attractive to me is that I think these cars have way more chassis than engine requiring a FV driving mentality. How do ITA Miata's compare to SMs as far as HP? Do the modifications in IT help enough or is just a minor bump in power over SM?

[camop]

The increase in HP is pretty small. In my 1.6L it is noticeable but not huge - maybe 15 to 20 WHP. The bigger difference for me was the chasis improvement and the Hoosier tires. Still a momentum drive.

The front runners in SM are doing very close to the same lap times that I do in a nicely prepped ITA Miata. A really good driver in my car could do 2 or 3 seconds better per lap than the top SM guys on the tracks I'm running.

Good luck!

[tnord]

power gains are actually probably smaller than what camop posted.

peak whp for the good cars at the runoffs dyno was 120whp or just north of there. the best one i've ever heard of was 122whp and change on a 1.6. expect the 1.8 to have a couple ponies more.

in IT trim i'm making a fairly educated guess that the best 1.6 will be just north of 130hp. i think the 1.8 can get to 140hp, but other credible people would disagree with me.

i don't think there's any area on an IT miata which is hugely improved over a SM, but rather lots of little things. a little better tire, a little better shock/spring combo, a little more power, a little less weight, and a little better aero should make the car consistantly quicker, but not by much.

[lateapex911]

The thing about the SM vs ITA Miata comparision is that people often feel the ITA versions aren't faster, "Look at the lap times" they say. But SM fast laps are always done in a pack of cars that drive identicaly. In a mixed marque class like ITA, getting a fast lep is difficult, becuse you are often slowed in the only places you can be fast, then left for dead on the straights. It's the classic momentum car issue.

[tnord]

The thing about the SM vs ITA Miata comparision is that people often feel the ITA versions aren't faster, "Look at the lap times" they say. But SM fast laps are always done in a pack of cars that drive identicaly. In a mixed marque class like ITA, getting a fast lep is difficult, becuse you are often slowed in the only places you can be fast, then left for dead on the straights. It's the classic momentum car issue.
[/b]

especially when the two main tracks you race at have ~40mph 2nd gear corners coming onto the main straight, it can be more than a little frustrating. probably part of the reason i think the 1.8 is a better miata to have.

[lateapex911]

Yup, and Andy will tell you that his 1.8 can win against stout cars at Lime Rock which has a "hang on downhill, off camber and bumpy" 80 -90 mph corner leading onto a semi short main straight. But at other tracks with longer straights and slower entry corners, he struggles.

Horses and courses.....

[Andy Bettencourt]

which has a "hang on downhill, off camber and bumpy" 80 -90 mph corner leading onto a semi short main straight. [/b]

102mph to be exact! Thank you DL1.

[tnord]

the sucky part is....

if you want to race in ITA, and you insist on a RWD platform (which i pretty much do), then i can't think of a better option than a miata. rx7? sorry, i can't get over the sound. 325e BMW? not enough of them built yet, so i don't know the true potential and would be hesitant to take the risk. 240sx? maybe, but i keep hearing the motors are grenades when built to be fast.

which leaves you with......the miata.

[joeracerx95]

Thanks for the information. It's what I was afraid of, just like the SM, it has more chassis than HP.

Like tnord, I insist on RWD. As far as the noise on a RX7, I can tell you from dyno testing that a RX7 isn't hurt power-wise if it has a muffler on it. Everyone says I go whoosh when I go by. :P

What we need now is a Spec-S2000 class. The Honda is just about perfect with that engine and chassis. If only they weren't so expensive.

[tnord]

the S2000 is classed in ITR for this year.

can you elaborate a little more on your disdain for cars "with more chassis than hp?" maybe you prefer it the other way around and AS would be a good choice, or look at the cars classed in ITR. they have plenty of power and will be plenty fast.

[lateapex911]

:P

What we need now is a Spec-S2000 class. The Honda is just about perfect with that engine and chassis. If only they weren't so expensive. [/b]

Ironically, the S2000 will be a similar car in ITR to what the Miata is in ITA.....

[JeffYoung]

Have done a fair amount of SM racing, I can also say that SM times benefit GREATLY at VIR from the ability to draft. When a gaggle of fast SMs run down the backstraight nose to tail they can pick up as much as a second or two from running alone.

I truly think this is one of the reasons you see SM times that are faster than ITA Miata times. ITA Miatas don't get the benefit of the draft the helps these aero challenged cars so much.

[tnord]

I truly think this is one of the reasons you see SM times that are faster than ITA Miata times. ITA Miatas don't get the benefit of the draft the helps these aero challenged cars so much.
[/b]

just gotta find a partner. mac, if i can keep up, we should work together in qual and through the first 1/2 of the race this year.

[IPRESS]

Other then Hallett & Memphis, every place will be new to me, so if I can.... I will ride your bumper. Those other cars will think we are an old 4 door Buick!
Mac

[Andy Bettencourt]

I truly think this is one of the reasons you see SM times that are faster than ITA Miata times. ITA Miatas don't get the benefit of the draft the helps these aero challenged cars so much. [/b]

While this is 100% true, the fact remains that there are literally only a handful of all-out prep Miata's out there. Another handful being built for 2007 but most are bolting on a header and Hoosiers and thinking they are going to rule the world...and that ain't the case in a region where there is competition.

[tnord]

While this is 100% true, the fact remains that there are literally only a handful of all-out prep Miata's out there. Another handful being built for 2007 but most are bolting on a header and Hoosiers and thinking they are going to rule the world...and that ain't the case in a region where there is competition.
[/b]

agreed. a solid but not great SM build is an upper-echelon IT build round here.

[joeracerx95]

the S2000 is classed in ITR for this year.

can you elaborate a little more on your disdain for cars "with more chassis than hp?" maybe you prefer it the other way around and AS would be a good choice, or look at the cars classed in ITR. they have plenty of power and will be plenty fast.
[/b]

Here's my criteria: (Probably not much different than most here)

Good handling.
Light weight.
Enough power so that the gas pedal isn't an on/off switch.
Reasonable costs.
Close competition.

Up til now I've been running Pro7 in CalClub, which uses 79-85 RX7s. Very close to ITA but they use a stock carb, stock exhaust manifold, spec tires and suspension. We get about 115-120RWHP. 20+ car fields so if you win you feel like you accomplished something. Nothing wrong, I just feel the need for some more speed. ITA looks like a good fit for my criteria.

The Miata has about the same HP but handles WAY better so its all about not scrubbing speed, drafting and never ever lifting. FV type driving. Nothing wrong with it, just not what I want to do.

AS? Too big, too heavy. ITR? Too expensive, no competition.

At this point it looks like converting my Pro7 RX7 to ITA is the way to go. I can probably find several seconds a lap improvement for not too much money, plus I can retain the reliability of the rotary engine.

[johnny yanez]

i think i have driven the first gen in every configuratio class there is,, and still believe its competive in ITA...In the last 20 years i have driven in GT3, ITS, ITA, PRO7, EP, in a first gen mazda,,, it not a momentum car and its not quite as expeensieve as miata,, but alot of fun,, the longevity of the motor make it a fine choice, and ease in setting it up,, at the present im building a ITA miata for the challenge of learning to drive it correctly, no so much for winning as its hard to do at my age, you use less brakes with miata, and smoother in and out while the rx7 you go in hard, brake and back on the gas hard, just my thought of the different cars

[joeracerx95]

i think i have driven the first gen in every configuratio class there is,, and still believe its competive in ITA...In the last 20 years i have driven in GT3, ITS, ITA, PRO7, EP, in a first gen mazda,,, it not a momentum car and its not quite as expeensieve as miata,, but alot of fun,, the longevity of the motor make it a fine choice, and ease in setting it up,, at the present im building a ITA miata for the challenge of learning to drive it correctly, no so much for winning as its hard to do at my age, you use less brakes with miata, and smoother in and out while the rx7 you go in hard, brake and back on the gas hard, just my thought of the different cars
[/b]

Thanks for the insight Johnny. If you're building an ITA I guess we'll be racing each other than. Got any 12a headers you don't need?

-chuck koos-

[BMW RACER]

ITR? Too expensive, no competition.

Hey now Chuck! Step up, build an S2000 and lets race.

Don't forget ITR is a new class.