Teach me about ITR 325's

[robits325is]

It has been pointed out to me offline that I may have inferred that ITS RX-7 drivers were creating a model that didn't exist by cherry-picking the best stuff from different models. What I was trying to do for Rob was to show him that the items he listed for the most part, were not low production stuff and indeed available on all RX-7's.

The model that is being created is the 89-90 GTUs. The desirable part from this model is the 5th gear ratio (.76 instead of .71). And even at that number, it is worse than most everything in ITS.

My opinion is when you can change so many pieces and create a parts room model that exceeds the model that was classified then there should be a re-evaluation. I think that some of these RX-7 models should be on an individual spec line just like the 92 325i should be on a different spec line from the 93-95 325i

[JeffYoung]

Rob, on the BMW, is that due to OBDI v. OBDII? Or is it some other fundamental differences between the two different groups of model years?

I'm just curious, didn't realize there were differences in the E36 run.

Thanks.

Jeff

[robits325is]

Rob, on the BMW, is that due to OBDI v. OBDII? Or is it some other fundamental differences between the two different groups of model years?

I'm just curious, didn't realize there were differences in the E36 run.

Thanks.

Jeff

The 92 had different engine internals; springs, pistons, non-vanos, and different cams as well as a different ECU and harness (eliminated by the ECU rule now)

[GKR_17]

The 92 had different engine internals; springs, pistons, non-vanos, and different cams as well as a different ECU and harness (eliminated by the ECU rule now)

And half a point less compression. Though the stock numbers show the same, that engine has a lot less potential than the '93 and later units. Except for the BMW stigma, the '92 might be a good fit without the SIR at near the current weight. I'm certainly not holding my breath though.

[Andy Bettencourt]

My opinion is when you can change so many pieces and create a parts room model that exceeds the model that was classified then there should be a re-evaluation.

But you are infering by saying 'parts room model' that what is on track never existed when in fact, peple are creating the 1989-1990 GTUs. Here are some facts for you:

It has no more HP than ANY other 89-91 RX-7
It has the SAME brakes as the GXL
It has the same rear wing as the GTU and GXL

The differences were a 4.30 viscous (vs 4.10 open) and the slightly upgraded 5th gear of that the only thing applicable to IT racing is the transmission...and oh yes, it did have an aluminum hood that it shared with the convertible.

And it wasn't limited production like the MT 325. Only about 1100 were made but that was due to lack of demand, not a limited production run. It was a fully documented model in the brochures.

[dickita15]

My opinion is when you can change so many pieces and create a parts room model that exceeds the model that was classified then there should be a re-evaluation. I think that some of these RX-7 models should be on an individual spec line just like the 92 325i should be on a different spec line from the 93-95 325i

All that would do is split out the 86-88 Rx7s which would have to be at a lower weight due to the lower horsepower.

[Andy Bettencourt]

All that would do is split out the 86-88 Rx7s which would have to be at a lower weight due to the lower horsepower.

Yup - 146hp. 2450 in ITS (never get there) or 2750 in ITA!!! Now THERE is an interesting idea...

[robits325is]

Yup - 146hp. 2450 in ITS (never get there) or 2750 in ITA!!! Now THERE is an interesting idea...

According to post #76 the horsepower on the "lesser" models is the same? or did I read that between the lines?

[JeffYoung]

Rob, the early 2nd Gen RX7s made 146 hp.

The later ones 160 hp.

All of the later model GL/GXL/GTU/GTUs made 160, which is I think what Andy was saying.

[Andy Bettencourt]

According to post #76 the horsepower on the "lesser" models is the same? or did I read that between the lines?

The 1986-1988 NA RX-7's all had 146 stock hp. The 89-91 NA RX-7's all had 160 stock hp - regardless of model. They are many mechanical differences in the motors. Nobody runs a 146hp motor in ITS.

[robits325is]

The 1986-1988 NA RX-7's all had 146 stock hp. The 89-91 NA RX-7's all had 160 stock hp - regardless of model. They are many mechanical differences in the motors. Nobody runs a 146hp motor in ITS.

If the 86 is 146hp and the 91 is 160hp then why are they on the same spec line?

[Greg Amy]

The 1986-1988 NA RX-7's all had 146 stock hp. The 89-91 NA RX-7's all had 160 stock hp - regardless of model. They are many mechanical differences in the motors. Nobody runs a 146hp motor in ITS.

And, if they were split out, then they'd also not have the bigger brakes, the rear wing, and the trick 5th gear, yes? Their only "parts bin" advantage versus the current ITS rocket is the lack of power steering.

Honestly, at the right weight, I think that would be a fine addition to ITA. And, it would give members the opportunity to race the 2nd-gen car competitively with minimal changes. A win-win as far as I'm concerned, and a great illustration of why it's a bad idea to put significantly different cars on the same spec line.

If the 86 is 146hp and the 91 is 160hp then why are they on the same spec line?

Same reason as the ITA 1.8L Miatas, and the E36s, and several other cars are: someone thought it was a good idea, that it would make for simplicity. In the end all it does is force preparation to the highest level in order to be competitive.

And that's not really what Improved Touring is supposed to be about.

GA