GSR's versus Z cars and E36's
- Thread starter four27
- Start date
Based on the limited information that I was able to coax out of folks, that was the best estimate that I could come up with, frankly. Your point about the older-tech engines actually seeing more of an increase under IT rules is making more and more sense to me, as I get additional data. The Mazdas (12a vs. 13b) seem to support your theory. As always, garbage in - garbage out, so (everyone) please feel welcome to share your information.
Kirk
Edit - remember that any arguments made against hobbling VTEC might apply to other manufacturers variable valve tricks as well.
[This message has been edited by Knestis (edited November 19, 2002).]
Crack Monkey
New member
Stock 12a rotary puts ~90hp to the ground.
SRX7 12a rotary puts ~105hp to the ground.
ITA 12a rotary puts ~125hp to the ground.
I do not know what a stock 13b puts out, but most SpeedSource cars put ~180hp to the ground.
The rotary can be tuned for more peak power, but sacrifice a LOT of power below 5500rpm. The figures I posted are what people actually use (The highest SRX7 hp I've seen is 107rwhp, but it had nothing below 6000rpm).
I only posted this since Kirk's multipliers were mentioned.
[This message has been edited by Crack Monkey (edited November 19, 2002).]
SRX7 12a rotary puts ~105hp to the ground.
ITA 12a rotary puts ~125hp to the ground.
I do not know what a stock 13b puts out, but most SpeedSource cars put ~180hp to the ground.
The rotary can be tuned for more peak power, but sacrifice a LOT of power below 5500rpm. The figures I posted are what people actually use (The highest SRX7 hp I've seen is 107rwhp, but it had nothing below 6000rpm).
I only posted this since Kirk's multipliers were mentioned.
[This message has been edited by Crack Monkey (edited November 19, 2002).]
Catch22
New member
I've only seen one stock 13B dyno result and as mentioned above it was 129. This would be in line with the factory claimed 150 at the crank.
So... a typically accepted 50whp gain for the 13b cars (and I've heard some have more than that) and if you believe a GSR can legally get 190 (which I don't) that's still 10 less at 40 (I've seen many stock GSR dyno pulls, including my own, and they turn around ~150whp).
A more reasonable estimation of LEGAL (I keep using that word don't I?) GSR power is ~175. Only a gain of 25. Half of the 13B.
Same multiplier? I think not.
And I realize it applies to ALL VVT motors, but I still stand by my logic that any manufacturer that puts the effort into VVT is going to have a damned good head on the car straight out the factory door. The gains we'll LEGALLY (there I go again) see will be minimal. Especially in comparison to a 13B rotary which pretty much everyone knows was seriously choked down from the factory and can be worked for HUGE gains.
At the end of the day, the 13B cars and the Integra GSR are going to have about the same hp and very little torque. The RX-7 will however have better brakes. So, if anything the GSR should at least be the same weight as the RX-7 but I'd think it should even be lighter due to the brakes.
Yes, I am biased. But again I'm trying to look at this from a purely logical perspective. That being "What advantage does the GSR have over the other top S cars to justify adding 75 to 100lbs of weight to it?" I just can't come up with anything.
So... a typically accepted 50whp gain for the 13b cars (and I've heard some have more than that) and if you believe a GSR can legally get 190 (which I don't) that's still 10 less at 40 (I've seen many stock GSR dyno pulls, including my own, and they turn around ~150whp).
A more reasonable estimation of LEGAL (I keep using that word don't I?) GSR power is ~175. Only a gain of 25. Half of the 13B.
Same multiplier? I think not.
And I realize it applies to ALL VVT motors, but I still stand by my logic that any manufacturer that puts the effort into VVT is going to have a damned good head on the car straight out the factory door. The gains we'll LEGALLY (there I go again) see will be minimal. Especially in comparison to a 13B rotary which pretty much everyone knows was seriously choked down from the factory and can be worked for HUGE gains.
At the end of the day, the 13B cars and the Integra GSR are going to have about the same hp and very little torque. The RX-7 will however have better brakes. So, if anything the GSR should at least be the same weight as the RX-7 but I'd think it should even be lighter due to the brakes.
Yes, I am biased. But again I'm trying to look at this from a purely logical perspective. That being "What advantage does the GSR have over the other top S cars to justify adding 75 to 100lbs of weight to it?" I just can't come up with anything.
Chris Wire
New member
Kirk,
Please don't use the 12a/13b engines to draw any conclusions about pistons engines, they are far too different to be of value to one another.
Due to the rather loud exhaust note of a rotary, they are horribly choked off at the factory with tiny exhausts and restrictive cast-iron manifolds. That's why the rotaries respond so well to a very open exhaust, coupled with a good intake system.
The japanese piston engines, OTOH, tend to be very good in production trim (I don't mean Production trim), therefore they tend to see smaller gains from the same IT-type mods.
------------------
Chris Wire
Team Wire Racing
ITS Mazda RX7 #35
[email protected]
Please don't use the 12a/13b engines to draw any conclusions about pistons engines, they are far too different to be of value to one another.
Due to the rather loud exhaust note of a rotary, they are horribly choked off at the factory with tiny exhausts and restrictive cast-iron manifolds. That's why the rotaries respond so well to a very open exhaust, coupled with a good intake system.
The japanese piston engines, OTOH, tend to be very good in production trim (I don't mean Production trim), therefore they tend to see smaller gains from the same IT-type mods.
------------------
Chris Wire
Team Wire Racing
ITS Mazda RX7 #35
[email protected]
Would be interesting to see what the GSR's are doing at your track. Below is the track records at Portland with no chicane. My best time was 123.5 Weight off the track was 2710. Track is 1.9 mile
AS 1.17 Camaro
ITS 1.20 240 z
T1 1.16 Viper
T2 1.20 camaro
ITA 1.24 ?
The typical ITS winner will be 121 and change and usually is a z car. How do the spreds look at your track for these class's
AS 1.17 Camaro
ITS 1.20 240 z
T1 1.16 Viper
T2 1.20 camaro
ITA 1.24 ?
The typical ITS winner will be 121 and change and usually is a z car. How do the spreds look at your track for these class's
Catch22
New member
My lap times are from NASA races and tend to be 2 or 3 seconds off the top SCCA ITS times.
Scott S. does a little better than me but also tends to be a couple of seconds off the fast laps of the E36s and RX-7s at places like CMP, VIR and Road Atlanta.
He does better down in his home area at Sebring and such.
Scott S. does a little better than me but also tends to be a couple of seconds off the fast laps of the E36s and RX-7s at places like CMP, VIR and Road Atlanta.
He does better down in his home area at Sebring and such.
First off, if Rob ever thinks he is driving my car again he is crazy.
As far as the weight of the GSR this is what I have been able to put together and will send to the Comp Board.
First just looking at all the Hondas in ITS:
1992 Honda Prelude Si
NADA Weight=2866 ITCS Weight = 2715
Difference = (-) 151
1994 Honda Del Sol VTEC
NADA Weight=2491 ITCS Weight = 2360
Difference = (-) 131
1994 Integra GSR
NADA Weight=2667 ITCS Weight=2690
Difference (+) 23
Anyone see a difference there. Now look at the E36 BMW
NADA Weight=3020 ITCS Weight=2850
Difference = (-)170
James Clay who could probably verify the manufacurers listed weight, is that correct?
But all the GSR owners need to start a letter writing compaign to the comp board since the GSR is being singled out with added weight and there must not be a consistent formula being used to determine the ITCS min. weight.
The ITCS weights are suppose to be calculated based on a un-biased method and in the case of the GSR it has been singled out and weighted down.
Scott Seck
#38 ITS GSR
As far as the weight of the GSR this is what I have been able to put together and will send to the Comp Board.
First just looking at all the Hondas in ITS:
1992 Honda Prelude Si
NADA Weight=2866 ITCS Weight = 2715
Difference = (-) 151
1994 Honda Del Sol VTEC
NADA Weight=2491 ITCS Weight = 2360
Difference = (-) 131
1994 Integra GSR
NADA Weight=2667 ITCS Weight=2690
Difference (+) 23
Anyone see a difference there. Now look at the E36 BMW
NADA Weight=3020 ITCS Weight=2850
Difference = (-)170
James Clay who could probably verify the manufacurers listed weight, is that correct?
But all the GSR owners need to start a letter writing compaign to the comp board since the GSR is being singled out with added weight and there must not be a consistent formula being used to determine the ITCS min. weight.
The ITCS weights are suppose to be calculated based on a un-biased method and in the case of the GSR it has been singled out and weighted down.
Scott Seck
#38 ITS GSR
Having looked at weight issues for almost three years non-stop now, a couple of hints?
** Take a look at the strand about the Corrado weight adjustment in the VW forum. I was amazed that this worked (the approach has failed for a number of other cars) but the guy who got the weight lowered must have hit some kind of a nerve.
** Whatever you do, don't make any claims based on (a) lack of competitiveness on the track, (
lap times of the GSR or any of its competitors, or © any other argument based on competitiveness. The powers-that-be will use the "no guarantee of competitiveness" and/or "no competition adjustment" hammer on you if you give it to them to hit you with.
** Argue ONLY for an "errors and omissions" correction, based on the case that the weight was incorrectly established in the first place. The data presented above is a good start, probably but it is still a long shot.
I will be rooting for you!
Kirk
** Take a look at the strand about the Corrado weight adjustment in the VW forum. I was amazed that this worked (the approach has failed for a number of other cars) but the guy who got the weight lowered must have hit some kind of a nerve.
** Whatever you do, don't make any claims based on (a) lack of competitiveness on the track, (
lap times of the GSR or any of its competitors, or © any other argument based on competitiveness. The powers-that-be will use the "no guarantee of competitiveness" and/or "no competition adjustment" hammer on you if you give it to them to hit you with.** Argue ONLY for an "errors and omissions" correction, based on the case that the weight was incorrectly established in the first place. The data presented above is a good start, probably but it is still a long shot.
I will be rooting for you!
Kirk
I will write the letter tomorrow and anyone that wants a copy of it can send me an email and I will forward them a copy of it that you can send.
And Kirk is right SCCA has made an error in the ITCS weight of the GSR or they have un-fairly weighted the car down, which they are not suppose to do.
Email me at:
[email protected]
Scott Seck
#38 ITS GSR
And Kirk is right SCCA has made an error in the ITCS weight of the GSR or they have un-fairly weighted the car down, which they are not suppose to do.
Email me at:
[email protected]
Scott Seck
#38 ITS GSR
Hey, while you're at it, why don't you drop my car in there too, Nissan NX2000 at 2461 NADA versus 2490 ITS weight (+29 lbs) starting with 30 less horsepower than you guys have...
<grin>
We're all in the same boat, guys. I encourage you to try, though, because your success will literally open the floodgates for everyone else.
GregA
LTBMotorsports
New member
Please and Please don't mention the ITS Delsol in your letters to SCCA because I am happy with 2360lbs and I don't want to add any weight.
Only if I can run 15'' wheels I will be more happy !!!!!!!!!
Louis B.
Only if I can run 15'' wheels I will be more happy !!!!!!!!!
Louis B.