The Ace

OK just got the first numbers/times for my Rex from the AC22, as promised

As for the settings (which should be correct in order to obtain proper readings) I only changed the tilt to 0.011 (sport street car) and the weight to 1450kg (1360kg car, 90kg me ). Left CdA and Rolling R "as is". Figured the numbers would be pretty close anyway.

So, first run, with my g/f in the car (so total weight is up by 60kg), pretty shitty road, kinda up-hill (maybe 2-3%), and not exactly straight (kind like a long curve). Anyway, I take off at 2,5K, WOT, shift at 7100, WOT, shift at 7100 to 3rd, and take a look at the numbers: a VERY shitty 8.04" for 0-100kph, and 186RWHP (which equals 216BHP ) I know the time is WAYYYY off, but if you could see the road you would understand....

Second -and last- run, road is better, pretty straight, all alone (so the weight is actually correct), take off at 3K, WOT, shift at 7100, WOT, shift at 7100 to 3rd, and the AC22 shows 7.45" for 0-100kph and 190RWHP That means 220BHP...

First thing: the times are way higher than expected. I know that the TII has 6.6"-6.7" for 0-60mph, but thats 0-96kph. I think that this is exactly the point that I need to shift to 3rd gear. That explains the whole 1" it takes me to go from 90kph to 100kph. It seems that the Rex is VERY powerfull for 0-60mph (I had 6.45" for 0-90kph, which means I should get something like 6.7 for 0-96kph, which would be 0-60mph), but relatively weak for 0-100kph (because you have to shift into 3rd). Even if this is the case, 7.45" is a rather slow time. Am I doing something wrong ? I know I can drop this time to 7.3" maybe, but that's still slow....

Second thing: RWHP. Amazing. It is well known fact that these devices underestimate the real HP of any given car, but if I take for granted that the reading is correct, 190RWHP is amazing That means 220BHP, and I have only done a K&N filter and catback. DP, TID are still to come....

Anyway, that's my story tonight. Let me know guys, what do you think ?

Stone

Hi Ace!

I guess you have to stop eating so much and start to loose some weight. (just kidding)

I think it's perfect for 0-100 km/h stock. I haven't got any mods at all yet. My airfilter (stock) is even totally clogged but I have a very nice, new conefilter from PiperCross which will replace the stock box soon.

Anyway, my weight is about 60 kg and it's perfect for me and my Rex, because when I reach redline in 2nd gear I'm exactly at or just passed 100 km/h... Then I go for 3rd gear and mmm...

When I have a passanger I end up not going past 100 km/h in 2nd gear so I need to shift into 3rd gear just like you..

Weight is evil and has to be destroyed

NZConvertible

Not necessarily. The RX-7 will have a relatively low CdA because the Cd (coefficient of drag) for these cars was pretty good, and they’re quite short, so A (cross-sectional area of the car) will be lower than for your average car. Dunno about rolling resistance though, that’s really only found through experiment. Do you have access to a drag strip? Comparing an accurate ¼ mile time with the unit’s time would allow you to tune these two parameters to your car.

NZConvertible

That makes no sense whatsoever. The relationship between engine speed, selected gear and road speed is fixed. It cannot be altered by weight. If a car redlines at 100km/h in 2nd gear with one person in it, it will still redline at 100km/h in 2nd gear with 10 people in it! It will just take much longer to get there...

Scott 89t2

not sure what you are using but for the g-tech you can only floor it in one gear for hp #. you have to get rolling really slow in 3rd, get it to display, then floor it. you can not shift.

NZConvertible

Scott’s got a good point. These meters are measuring acceleration over a time period, so any blip in that acceleration from a gear change will result in a lower power reading.

The Ace

Well, here's the lowdown:

I am not overweight. I'm just 1.86m tall, and been going to the gym since I was 14

Unfortunatelly, no. I will calculate the "correct" CdA and RR from the site of Race Technology, but I doubt these will alter the readings much. I think Tilt Factor is more important, and I already have it at 0.011, which is normal street sports car.

Yeah I know (hey NZ, give Stone a break ) I just thought that TIIs had ratios that allowed 2nd to reach 100kph in stock (or close to stock) form. I will have to find out my times for 0-60mph, and compare the times. From my last run last night, I got a 6.45" for 0-90kph, so 6.7" for 0-96kph (0-60mph) should be actually attainable pretty easily.

I'm using this:

http://www.race-technology.com/WebPa...omparison.html
http://www.autospeed.com/A_0703/P_1/article.html

and for a comparison go here:

http://dspace.dial.pipex.com/ian.crocker/AC22.html

You can always see the HP readout for any specific gear, but you can also see the peak HP and G-force produced. For me it was 190RWHP 5.1secs into the run (should be the max HP when I was in 2nd gear), and 0.51g

I know that my settings and readings are not perfect, but whatever they are, they are anything but overrated. So the numbers I got should be something like a minimum
Anyway, what I was worried about is the rather slow time for 0-100kph, although the 0-90kph is VERY nice. Must have been the gear shift...

The Ace

Oh and something else: just got a reply from Race Technology, saying that they dont have any specs for the TII, such as Tilt Factor, CdA and RR. The last two can be -easily ??- calculated with coastdown runs, but what about the Tilt ? Anyone has any specs, hook me up !