GoodfellaFD3S

iTrader: (213)

Was poking around the web and came across this:

http://www.rx7.com/accel_calculator.html

According to the calculator, my FD will run an 11.97@118.31 at 12 psi . An 11 second car on low boost, I'll take that, lol. To get those results, I entered in 342 rwhp, 2875 pounds (weight with driver), 3 shifts, 25 inch tire height (stockers) and 4.10 gear.

spoolin93r1

only bad thing about calulators like that is you never know to go by rwhp or flywheel hp

GoodfellaFD3S

iTrader: (213)

Actually, if you back up one screen, there is a short writeup where rwhp is specified.

Rich

r0gu3

Seems pretty accurate trap wise, but I'm sure it would be accurate if I could hook up for the ET.

12.27 @ 115.13 at 10.5 psi.

jimlab

10.55 @ 135.38 at 0 psi

Edit: Oops... entered 4 shifts the first time. I doubt I'd hit 5th in the quarter.

3,000 lbs., 550 RWHP, 3 shifts, 25 inch tire, 3.55 gear

r0gu3

You can push that car fast!















Just kidding around. :p

jimlab

Yep. 0-Floor in 0.2 seconds.

Red-Rx7

9.44 @ 142.69; 13.5 psi.

8.71 @ 154.48; 27 psi.

This was calculated with the weight of the car including me, & gas.

Looks good on paper. But, in reality, I see my tires spinning or the rear end hopping, etc.

Interesting enough, if I removed 100lbs from the car (for my car has full accessories & more):

9.34 @ 144.15; @ 13.5 psi
or
8.62 @ 156.06; @ 27 psi.

Interesting how much I would have to sacrifice in weight for that small gain in speed. I think I will keep my 7" touchscreen, 1ghz computer, and the fast and the furious DVD.

GoodfellaFD3S

iTrader: (213)

If there was any doubt that the the three rotor will crush anything.......a mid 9 second pass on low boost/pump gas. I doubt any of the V8 muldoons can top that......

1QWIK7

iTrader: (33)

thats a cool tool

but obviously it just gives your a general idea..

i love to walk around saying i can run 12.5

but they forgot numerous factors that play a part in running the 1/4

i guess we just have to do the 1320 to find out

jimlab

What did you enter for weight? Entering 620 RWHP, 2,850 lbs., and 3 shifts, I got 10.05 @ 142.41. Even with 1 shift, I couldn't get it to cough up a 9.44. What gives?

BTW, what are you estimating that your horsepower would be at 27 psi? And for how long?

jimlab

The trap speed is pretty much right on the money. The simulations that I ran with the gearing I chose also indicated a 135.xx mph trap speed. Obviously the E.T. is potential performance.

zmarko

I guess I need to get a baseline before I can use this. lol.

Cool tool.

jimlab

There's a guy named Baxter running a supercharged LT1 in a 3,900 lb. Camaro convertible that is in the 8s. Let's see what the 20B would do in a 3900 lb. car.

Muldoons. I like that.

GoodfellaFD3S

iTrader: (213)

Well, I am annointing you King of the Muldoons. Don't you feel honored ?

I dunno, dropping a 20B in a 3900# car makes about as much sense as FD Altezza tails.....

Rich

Red-Rx7

My input values:

weight 2922 (thats what I weighed in as on a truck scale; for it is the only thing I have to go on).

640 rwhp. 630 was at 6100 rpm. I estimated 10 more rwhp in 1600 more rpm.

0 shifts. I have a clutchless transmission.

With regards to the 27 psi, I was not estimating. We dyno tuned the car for up to that PSI. I didn't publish the dyno graph for that PSI, for a few reasons:

1) It wasn't as high as we expected it to be (turbo too small)
2) The intake tempatures started going up very very fast at that PSI. I don't feel it to be very safe, so I don't really consider the numbers all that valid. But this thread is about potential, and that is what it is.

jimlab

A.K.A. automatic. Gotcha.

Okee doke. So XXXX RWHP.

Scrapiron7

Hmm..

HP: 330
Weight: 2885 (2720+165)
Shifts: 3
Tire height: 25 (same as stock)
Gears: 4.10

Results:
Power to weight: 8.9
E.T.: 12.17
Trap Speed: 116.27
Trap RPM: 6413


Guess I need to find out how accurate this is

spoolin93r1

hmm, showing me at 11.15 @ 127.7 on my pump gas tune. i really need to get tuned for 21psi

Red-Rx7

A.K.A, dog box transmission. The shift times are rated in miliseconds, so it is nearly as fast as an automatic. But, it is still a 5 speed with my own gear ratios.

I would never have an automatic in a car like this.

With regards to the rwhp, yes. But, I have edited it out; for I would rather have creative minds do the math. I don't want to have everyone PM me every day on how much my car put down in RWHP.

Thanks,
Mike

jimlab

You still have to shift a transmission with dog rings. You may not have to depress the clutch each time, but there's still time involved in the shift. You're saving a few tenths of a second, but that's it.

Red-Rx7

According to the calc:

"If you are running a clutchless transmission, or if you do not let off the accelerator pedal, input 0 (zero) for number of shifts."

.. and that is what I did. As far as time being involved in the shift, you are correct. Shift times have been measured at 35 miliseconds. So again, the time the calc spit out is as accurate to me as to you.

jimlab

Ah. I didn't read the instructions. Of course, the instructions also state that you should enter the final drive ratio of your transmission for the gear entry, which is clearly incorrect.

ForceFed

Hmmm. So everyone is getting accurate trap readings for this? It didn't for me.

Riddle me this Batman:

I have stock FD, dyno'd 219 HP. It weighs 2850lbs with me in it(I'm a little guy) and spare tire removed. With stock tires/wheels and stock rear end I came up with a trap speed of 101mph (it spit out a ET of 13.68)

Here is a video of me running the 1/8th mi at a local track on a hot and humid summer evening in Charlotte NC. Track Elevation is 850 ft.

http://davidhillsoftware.com/Videos/...eds8.7run.mpeg

That was my slowest pass on video. Out of 3 runs and having not been to the track in over a year I netted a 8.5@83mph as my quickest pass from that night. That 1/8th mi trap is good for a 106-107 trap. What gives?

Red-Rx7

You are estimating your trap speed, and don't.

It was a good run, but stock 3rd gen's don't trap 107+ in the 1/4 mile.