PDA

View Full Version : Miatas in ITS



mapper
11-10-2003, 08:52 AM
The 1.6 Miata is classed in ITA and some 1.8 years are classed in ITS but they both have a home in SM. For those who do not want to run SM, can a 1.8 car be competetive in ITS against the RX-7 and Z cars? There is already a discussion on the board about the 1.6 cars in ITA so I am really interested on your thoughts about ITS.
Steve

Blix
11-10-2003, 04:23 PM
I can't imagine how the 1.8L could be competitive vs the RX7, Z, and especially the BMWs. They are really fun and nimble, but I can't see the power being there. Call and talk to Sunbelt Motors, the factory supported shop, and see what they think they could make at the wheels. You also don't have alot of gear ratios to choose from.
It would, however, make a GREAT endurance car...there is one running somewhere, as they finished second to a Carrera Cup car at the 12h at Summit Point.


Eric
NER SM #02

oanglade
11-10-2003, 05:14 PM
The more I think about it, the more I think that it could actually work. At least it should be able to compete with the 2nd gen RX-7. Don't know about against the 325.

Like Blix says, it all depends on what an engine builder can squeeze out of the 1.8 within the rules. It should be able to make a decent amount more than the 1.6 motor, in my opinion, since it doesn't have the bottleneck flow meter. The cams would be the bottleneck on the 1.8. I am no expert, but I bet that a well built IT 1.8 Miata can put down 150hp to the wheels with ECU tuning, etc.

2200 lbs and 150hp = 14.67 lbs/hp

This is about 180hp for the RX-7 and about 190hp for the 325i.

So, it depends on how much juice they can squeeze out of the little lump.

The handling should be as good or better as the rest and it should be very reliable and good on parts. Great for long races.

Banzai240
11-10-2003, 06:04 PM
Originally posted by oanglade:
The handling should be as good or better as the rest and it should be very reliable and good on parts. Great for long races.

The fastest of the SMs at Portland International run about 1:24 - 1:25s... the ITS Track record is 1:20 and change, and the fast ITS cars currently run around 1:21-1:23, without the chicane... Not sure of the "Litre-ness" of the SMs running up front...

DJ

oanglade
11-10-2003, 06:16 PM
Yeah, at Road Atlanta a 1.6 SM ran last year a 1:46.0 last year on Toyos and at a min. weight of 2255, compared to 2200 in IT and possibility of running Hoosiers. The top ITA cars run 1:44.0 and the ITS cars 1:41.0
The Spec Miatas runs SS rules motors and diff, plus a spec suspension that might not be the best choice ever under IT.

This year they (SM) ran low 1:46s on new Hoosiers, but at 2300 pounds.

And those are 1.6 cars (the 1.8 is restricted). An unrestricted, IT built 1.8 should be quite a bit faster than an SM.

[This message has been edited by oanglade (edited November 10, 2003).]

MMiskoe
11-10-2003, 10:22 PM
Well, let me tell you what I know. Being one of the drivers of the above listed 1.8l that finished behind the supercup 996 at the last Summit 12 hour, I feel I can speak w/ some experience.

The car we drive is a '95 that started out as a motorola cup car, then went SM and is now ITS. The rational was that in a 12 or 24 hour race, SM is just a long sprint, there is nothing to use as competative advantage. In ITS the lack of abuse on parts is the Miata's edge. This keeps it out of the pit lane more than the other cars. In sprints this theory doesn't work (obviously), the race needs to be somewhere in the 6 hours or longer range (I think).

The car won't make the 2200# min weight legally, at near zero fuel and a 155# driver we're at 2305. I've looked at everything on that car for weight and you might find another 25#.

I'd be impressed if you could make 150 crank HP legally. We've done the .040 over and headers and messed w/ air cleaners (the only thing on the intake you can change due to its layout) and I don't see it getting there. The guy building the motors hasn't found it all, but I am confident he has moved the big rocks. Now that I've said that, he'll probably prove me wrong (hope he'll try at least). The good Sunbelt motors that I have seen in SM on the dyno are in the 120 range (w/o restrictor). Maybe someone else can say more about this.

We've run Khumos, Toyos and Hoosiers on it. The Hoosiers did not do huge things for it, the Toyos in the long run were easier to drive therefore yeilding more consistant lap times.

I would disagree w/ the comment that there are limited gear choices, I was under the impression you can get most any gear set 4:10 through 4:50.

I've run it in sprints and found the same thing w/ the enduro qualifiers. It doesn't have what the RX'7, 325's and 240z's have for overall lap times.

The factory support is awesome. In comparison to my own Nissan's, Mazda comp is amazing. The car owner will send me an email telling me that parts are on their way, and the parts are on my doorstep before I get to read my email.

It is also a hugely fun car to drive.

Hope this helps.

Matt

oanglade
11-10-2003, 11:17 PM
You certainly know more about it than I do. I suspected that getting to 2200 would be an issue. We may be able to get there with a 1.6, maybe, barely, so I know that it's not as easy or may not be possible with a 1.8 car.

As for the power, I'm just guessing, based on what I've seen 1.6 SM's and ITA cars put to the wheels as well as street 1.8s, but I know I could be off. I've seen SM 1.6 motors put more than 115 to the wheels. A 1.8 should be able to put out a nice chunk more and then I thought that it would be able to benefit from reprogramming the ECU and the other IT legal mods. Maybe the 1.6 just has more potential? It would be awesome though...

mapper
11-11-2003, 08:43 AM
Another thought: The 99s will be elegible for IT in 2004 though I doubt they will be classified anytime soon. 140 hp at the crank stock as the 99s had better cams and a higher compression ratio. They have about the same weight as the 1.8 first generation cars but I don't know if there is as much potential for weight loss. The 99s have dominated SSB and Solo II CS over the 1st gen 1.8s so maybe there is some potential to be found there.

Steve

oanglade
11-11-2003, 09:53 AM
The '99 head and cam is a lot better than the earlier 1.8 cars. They also have a little bit wider track and the car is stiffer. It would depend on what weight they get classified at and if they could make it.

------------------
Ony