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Jiveslug
08-15-2002, 02:01 PM
Hey everyone. So here is a question. I have been thinking about what car I want to run in IT, and have pretty much decided that I want to do ITA. I know the CRX Si is the car to beat, but I really dont want to run a Honda. Ive also looked into the various Toyotas, but they seem to have a weight problem. Id like to look into Nissan. Thus, here is the question I have. I was looking at the car classifications, and I noticed that the B13 Sentra with the 1600 is qualified for ITA. The NX2000 is qualified for ITS, as is the Sentra SE-R. The NX Coupes were built on the B13 platform using the same engines, trannys, suspension, etc. Looking at the stock specs of the NX1600, it has a curb weight of 2350 lbs, and has stock power figures of 110hp and 108ft/lb. Thats a bit heavier than the CRX, but also with a bit more power. Has anyone ever petitioned to have these cars added to the GCR? It seems that these might make good ITA racers. What is everyone elses' opinon?? Thanks!!

Jive

Geo
08-15-2002, 03:52 PM
Originally posted by Jiveslug:
Hey everyone. So here is a question. I have been thinking about what car I want to run in IT, and have pretty much decided that I want to do ITA. I know the CRX Si is the car to beat, but I really dont want to run a Honda. Ive also looked into the various Toyotas, but they seem to have a weight problem. Id like to look into Nissan. Thus, here is the question I have. I was looking at the car classifications, and I noticed that the B13 Sentra with the 1600 is qualified for ITA. The NX2000 is qualified for ITS, as is the Sentra SE-R. The NX Coupes were built on the B13 platform using the same engines, trannys, suspension, etc. Looking at the stock specs of the NX1600, it has a curb weight of 2350 lbs, and has stock power figures of 110hp and 108ft/lb. Thats a bit heavier than the CRX, but also with a bit more power. Has anyone ever petitioned to have these cars added to the GCR? It seems that these might make good ITA racers. What is everyone elses' opinon?? Thanks!!

Jive

See my response in the General forum. But I think it's a great idea. There is some work being done these days to develop that engine as well, although most of that is not IT legal. But, folks are finding more out about these engines. For years they were ignored in favor of the SR20DE.

Let me know if you need some help.




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George Roffe
Houston, TX

84 944 ITS car under construction
92 ITS Sentra SE-R occasionally borrowed

Greg Amy
08-15-2002, 03:54 PM
<font face=\"Verdana, Arial\" size=\"2\">...NX1600...might make good ITA racers</font>

Interesting question. I can't offer a qualified answer, but I can tell you that I am building an NX2000 for ITS. I've competed twice in it and I've yet to beat the winning Honda CRX driver's times. (Tom Blaney)

My car's forte is weight and brakes. I think that it's likely I will evolve the car and driver combo to be faster than ITA, but I just can't imagine trying to do it with 30-40 less horsepower, smaller brakes (and drum rears, right?), and a wider-ratio economy transaxle. The GA16 is a very good engine, but it's down on power compared to the Honda engine.

The legal weight for the ITS NX2000 is 2490 (and the SE-R is 2450), so you could do some comparitive analysis to guesstimate what weight they'd classify it at (SCCA will not release the figures it uses to determine legal weight for IT cars.)

If you'd like to pursue it I'd be glad to help you, but with a quick glance of the numbers I think it would be a long row to hoe to be competitive.

It would be a hell of a lot of fun to try, though...

GregA
http://www.gatm.com/cars/nx2000

Jiveslug
08-15-2002, 04:29 PM
Interesting.... Very interesting.... Im just starting the research part of this, but I personally am of the opinion that the NX may have some potential. I was looking at the b13 Sentras, and like George, I thought that might be interesting as well. However, I thought about the fact that Im gonna be racing in SoPac and that most of the tracks here are high speed (PIR, Vegas, Willow Springs). It came down to one word.... Brick. As in the Sentra is as aerodynamic as one. Anyway, the NX1600 should be able to handle just as well as the SER Sentra or the 2000. I should be able to use the same tricks/techniques as the ITS guys. As far as brakes are concerned, Im not too worried about it. The Hondas have rear drums too, and they are the car to beat. Thus, the only real questions revolve around the driveline. I dont have any specs on the gearbox, so Id be interested to see a comparison between the 1600s and the 2000s. For the motor, that may simply be an issue of development. The Hondas start out at around 105hp, and I believe they race at 2000#? So, doing a quick calculation, It looks like, extracting 15% more power, the CRX is in the 120-122 range. Using that same calculation, the 1600 should be about 127-128 or so.... If the 1600 has the same race weight as the B13 Sentra at 2250, in order to have the same power to weight ratio as the Honda, it will need to make about 135hp.... Possible?? Dunno. Any thoughts???

Jive

PS George, thanks so much for your offer to help. Im still in the research stage, but if and when it comes time to get it qualified, Id love any help you could offer!

Geo
08-15-2002, 05:45 PM
Originally posted by Jiveslug:
I thought about the fact that Im gonna be racing in SoPac and that most of the tracks here are high speed (PIR, Vegas, Willow Springs). It came down to one word.... Brick. As in the Sentra is as aerodynamic as one.


Actually, don't be taken in by the shape itself. My understanding is the B13 Sentra is more aerodynamic than a C4 Vette. Aero can be extremely deceiving. It's generally not intuitive.


Originally posted by Jiveslug:
Anyway, the NX1600 should be able to handle just as well as the SER Sentra or the 2000.


100% correct. We will have some development parts in the next year that should be a big improvement over the current "street" aftermarket parts.


Originally posted by Jiveslug:
If the 1600 has the same race weight as the B13 Sentra at 2250, in order to have the same power to weight ratio as the Honda, it will need to make about 135hp.... Possible?? Dunno. Any thoughts???


That might be tough. The engine will definitely require some careful attention to get near that. If you decide to do this, Bob Legere (who is on this forum - building an ITB Opel) has considerable experience building race GA16DEs. He engineers Tim Mathers GA16DE powered Sentra rally car.


Originally posted by Jiveslug:
PS George, thanks so much for your offer to help. Im still in the research stage, but if and when it comes time to get it qualified, Id love any help you could offer!

I'd be glad to gather up the pertinent stats to send to the CB for you.

I have a 91 and a 92 B13 FSM. I'm sure I can get the 93 info from someone else on the SE-R Mailing List.


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George Roffe
Houston, TX

84 944 ITS car under construction
92 ITS Sentra SE-R occasionally borrowed

Geo
08-15-2002, 05:49 PM
Originally posted by grega:
My car's forte is weight and brakes. I think that it's likely I will evolve the car and driver combo to be faster than ITA, but I just can't imagine trying to do it with 30-40 less horsepower, smaller brakes (and drum rears, right?)....

Don't forget he'll probably come in 200 lbs lighter than your NX2000 Greg. As for the brakes, I think they are the same as the SE-R and should still be pretty capable. The rear drums is a bummer, but thems the breaks.

It's definitely not the popular pick, but could be a very interesting project. Think about yours Greg. After 2 outings already you've come a lot closer to the front than you thought would be possible with your car and you have a fair amount of development to go.

The only real drawback to the NX1600 I think would be used parts availability. In that I think the Sentra would be king.


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George Roffe
Houston, TX

84 944 ITS car under construction
92 ITS Sentra SE-R occasionally borrowed

Ascona1973
08-15-2002, 06:08 PM
Geo wrote:

"Actually, don't be taken in by the shape itself. My understanding is the B13 Sentra is more aerodynamic than a C4 Vette. Aero can be extremely deceiving. It's generally not intuitive."

Good call Geo, I didn't think anyone remembered that fact! I believe the cd of the Sentra is .34, although I also understand the NX is slightly better. I would possibly forgo the improved aerodynamics for the cheaper body shell with readily available parts. Also, the NX's open rear hatch adds a lot more flex to the chassis, and the Sentra chassis already has rear strut-tower flex issues. A carefully designed cage is paramount if you intend to extract everything from the car's suspension,
they really start to move around with higher spring rates.

But hey, if you already have a lead on an NX bodyshell, go for it. Swap in a later model engine with the larger intake ports, retune the ECU (legal, and there's a lot of top-end power to be gained with a recurve of the variable intake cam timing), and build a good header and exhaust (the exhaust port/system is quite restrictive).




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Bob Legere
ITB Opel Ascona under construction

ITA240
08-15-2002, 11:06 PM
Jiveslug,
You mentioned running several high speed tracks. I might add that, although it is a completely different platform, The S13 240SX also runs as and ITA car and it REALLY likes to stretch its legs on high speed tracks. ( I can think of one recently that was pulling a nicely prepared ITS SE-R around a very large track in the Southeast)

But, they do have their problems also

Jim

dpc
08-16-2002, 08:18 AM
If you are thinking of building a new car, Look at the classifieds 240sx ITA, not cheap but new

racer-025
08-17-2002, 09:53 PM
Do all the 1600's have the same t-bar glass roof that the 2000's have? I do like the concept of a ITA NX1600. I hate that t-bar roof. What are the years of the 1600 and the 2000? Can any of them get rid of the t-bar roof from the updating/backdating rule?

Geo
08-17-2002, 11:51 PM
Originally posted by racer-025:
Do all the 1600's have the same t-bar glass roof that the 2000's have? I do like the concept of a ITA NX1600. I hate that t-bar roof. What are the years of the 1600 and the 2000? Can any of them get rid of the t-bar roof from the updating/backdating rule?

I'm not 100% certain, but I believe the T roof is either rare or non-existant on the 1600. With the 2000 there are a few cars that had the hardtop, but they are rare and desireable for racing.


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George Roffe
Houston, TX

84 944 ITS car under construction
92 ITS Sentra SE-R occasionally borrowed