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-   -   Automatic DOGGY off the line! NORMAL? (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/automatic-doggy-off-line-normal-116996/)

DashKits.net 09-22-02 09:50 PM

Automatic DOGGY off the line! NORMAL?
 
My 93 RX7 i bought is
SOOOOO doggy off the line...

i mean, i put it down and NOTHING happens (the pedal actually feels heavy too)... then
turbo 1 kicks and i take off.

IS THIS NORMAL?
Can i do anything to REMEDY or help this?

thanks!


Sales@DashKits.net

DashKits.net 09-22-02 09:59 PM

ttt
thanks

P'cola FD 09-22-02 10:01 PM

Do a 5-speed swap. ;) J/K
They usually are less quick off the line due to the taller gears and the auto tranny. You can ask Jonski and MAx Pesce about launching techniques. I own a 5-speed, but I figure if you want a better launch, then you are going to want to power brake it a little to get the turbo spooled. Hold the brake down, then floor the pedal, once the rpms climb some, let off the brake.

johnchabin 09-22-02 10:06 PM

This may be a silly question, as I know nothing about the automatic FD, but here goes:

Can the torque converter be swapped with something higher performance? Seems to me a buddy did this with his Trans Am back in high school. It made a huge difference in his launch.

jf4828 09-22-02 10:07 PM

There was a thread last week about launch techniques in autos.... I have a 5 spd, but if I remember correctly you have to hold @ ~ 2500 w/ powerbrake... They are not nearly as quick of the line, but you should be passing most things on the road by second gear...

ejmack1 09-22-02 10:30 PM

5 speed conversion is the way to go, im about 200 miles into and and have no regrets!!!!

turbojeff 09-22-02 10:34 PM

They are doggy off the line, short of a 5spd conversion you might try getting just a diff out of a 5spd. Autos have a 3.90, 5spds have a 4.10.

You should be able to find a diff for $250 or less, install isn't that hard. Your speedo will be off but the car should feel more lively around town.

Jeff

JONSKI 09-23-02 11:56 AM

This is a copy and paste from a post I made in the kills section not long ago.

Launching in an AT FD isn't as easy as many think. As stupid as this may sound, launching the AT FD takes practice and know-how.

Here's how it's done:
- Press hold and select 'L'.
- Brake torque to 2500rpm.
- Release gas, but don't depress the accelerator any further.
- At 3000rpm, GRADUALLY depress the accelerator.
- At 5000rpm, you should be at full open throttle
- When you hear the buzzer, select the next gear

This is THE fastest way to launch the AT FD.

maxpesce 09-23-02 01:01 PM


Originally posted by JONSKI
This is a copy and paste from a post I made in the kills section not long ago.

Launching in an AT FD isn't as easy as many think. As stupid as this may sound, launching the AT FD takes practice and know-how.

Here's how it's done:
- Press hold and select 'L'.
- Brake torque to 2500rpm.
- Release gas, but don't depress the accelerator any further.
- At 3000rpm, GRADUALLY depress the accelerator.
- At 5000rpm, you should be at full open throttle
- When you hear the buzzer, select the next gear

This is THE fastest way to launch the AT FD.

:withstupi
But with slight Changes:
line 3 should read, release BRAKE and EASY onto the throttle untill 3000-3500rpm (or 10psi boost which ever comes up first)
at 5000 rpm Release the HOLD button and the tranny will shift to second at 6500k rpm ( the rpms will be climbing so fast that it will hit the buzzer before the shift is complete) if you have done this right it WILL spin the tires when shifting to second and you may need to feather the throttle if the track/street surface does not have good grip.
As soon as the tranny completes the 1-2 up shift move the lever from L to S, you will only have about 2 seconds to do this before you hit the rev buzzer again :D
for a 1/4 mile run unless you can do better than 110-115mph just leave it in S (third) otherwise move the lever to D at 6500 rpm

turbojeff 09-23-02 01:19 PM

There are two problems with "launching" a auto FD like this.

1. It is hard on the tranny.

2. An extreme way to drive in traffic isn't it? What kind of moron are you going to look like when your sitting at a stoplight with your foot on the gas and brake trying to build boost.

Just swap the diff...

Jeff

brads 09-23-02 01:36 PM

dog is correct!
 
the auto will always be a dog out of the hole. unless you get a upgraded torque converter and tranny.

i agree with most of the above. but since the second turbo comes online around 5500rpm in 1st gear, i dont release the hold until around 6500. that way it shifts to second right before the rev limiter, around 7200. but, i think im having a problem with the turbo transition in 1st gear. most of the time it will build full boost around 3000rpm, then it dips to around 6-7psi and slowly increases till the second turbo comes online. so i only fill like im getting full power in 1st gear from 5500rpm-redline.
did that make any sense? if so, does anybody else experience this. it might just be normal. man i wish i would have bought a manuel rx7.
-brad

brads 09-23-02 01:44 PM

yes but
 

Originally posted by turbojeff
There are two problems with "launching" a auto FD like this.

1. It is hard on the tranny.

2. An extreme way to drive in traffic isn't it? What kind of moron are you going to look like when your sitting at a stoplight with your foot on the gas and brake trying to build boost.

Just swap the diff...

Jeff

1. yes it is hard on the tranny, but so is speed shifting a 5spd. or dropping the cluch at 4000rpm of the line.
2. why would you do this at a stoplight? this is something you would do when racing someone, or just running your car.

yes the diff swap would be great.

maxpesce 09-23-02 01:44 PM

brads: Mine comes on so strong at 4500-5000 rpm in first that it breaks the tires loose and spins up to the readline in about 0.5sec.
turbojeff: I ONLY use torque braking at the track when racing - never on the street. even then I only stay on the brakes for about 1sec and release as soon as I get 2500rpm (ie DON'T hold the rpms at 2500 while stationary)

TeamChin 09-23-02 01:47 PM

i've heard rumors that if you upgrade the auto tranny....it's poss. to make it as faster or even faster then the manual??? any truth to this???

brads 09-23-02 01:48 PM

max- yeah its probally just normal. i dont break the tires loose. i have pretty good tread. but ive gave a few passengers whiplash, LOL. yeah once it hits around 4500rpm youve got to react quick to shift before the rev limiter.

brads 09-23-02 01:53 PM

faster
 

Originally posted by TeamChin
i've heard rumors that if you upgrade the auto tranny....it's poss. to make it as faster or even faster then the manual??? any truth to this???
i raced a manuel last week (p'cola fd). he has the same mods as me, minus the smic. from a deadstop, he didnt pass me untill around 100mph. granted he spun the tires threw 1st gear, and my car doesnt spin at all. then we went from a roll. he maintained a good car length gap between our bumpers, all the way to 130mph.

turbojeff 09-23-02 05:23 PM

Re: yes but
 

Originally posted by brads


1. yes it is hard on the tranny, but so is speed shifting a 5spd. or dropping the cluch at 4000rpm of the line.
2. why would you do this at a stoplight? this is something you would do when racing someone, or just running your car.

yes the diff swap would be great.

1. I don't launch the car off a stoplight, 5spds will just leave the line quicker without abuse.

2. I wouldn't do this leaving a stoplight. In real life you might not be racing everyone but the auto is so damn slow off the line it is frustrating. I had a auto Touring and my 93 R1, I know extactly how pathetic they are off the line in day-to-day traffic.

The 4.1 diff will help. Launching techniques won't.

Jeff

bajaman 09-23-02 06:53 PM

Re: dog is correct!
 

Originally posted by brads
the auto will always be a dog out of the hole. unless you get a upgraded torque converter and tranny.

i agree with most of the above. but since the second turbo comes online around 5500rpm in 1st gear, i dont release the hold until around 6500. that way it shifts to second right before the rev limiter, around 7200. but, i think im having a problem with the turbo transition in 1st gear. most of the time it will build full boost around 3000rpm, then it dips to around 6-7psi and slowly increases till the second turbo comes online. so i only fill like im getting full power in 1st gear from 5500rpm-redline.
did that make any sense? if so, does anybody else experience this. it might just be normal. man i wish i would have bought a manuel rx7.
-brad

My car does a damned near instantaneous transition...I mean it pulls 11 to 12 psi then dips to 8 or 9 for just a second or so and then goes right back to full boost of 11 - 12. In cold weather it will hit fuel shut-off in fact.
I love that initial boost surge followed very quickly by a BIG shove in the ass.....whooooohoooooo!

Auto FDs are a BLAST....from a rolling start! :D

JUSTgotMINE 09-23-02 07:38 PM

So how much is this new diff everyone talk about....links to where one would inquire to purchase one????

brads 09-23-02 07:44 PM

diff
 

Originally posted by JUSTgotMINE
So how much is this new diff everyone talk about....links to where one would inquire to purchase one????
try the parts section of the forum. post a WTB ad. unless you just have money to spend, i would buy a used one with low miles.

BNA_ELLIS 10-08-02 06:53 AM

I've imported a 1998 touringx auto from japan a few months ago. I will suprise a few 3 pedal have a go hero out there. First turbo come on at 2000 rpm the second at 4300. The torque converter will lock at 2800 rpm. If you get the right take off you will fly because you are already on boost. I plan on getting a 4000 rpm stall speed torque converter so I can really fly off the line. What you want is a 4000rpm stall speed torque converter. don't worry about diff or changing to a manual. I have a blitz catback and induction kit. I beat most cars without using hold button. The 98 version is tuned a little differently from the older ones though. The ecu controls turbo different etc. You don't have to use hold button to race really. Just put the auto box in s floor it, when you get to 6500 fora brief millisecond take your foot off gas then reapply it will change into second at about 4800 rpm and you'll flying towards the infamous buzzer again ready to change to 3rd gear. The auto can suffer alot mor abuse than the manual for sure.
My car was used for drifting in japan before I had it. It's got 27,000 miles on the clock. I drive like a nutter at the best off times, and have no issues with my auto box holding up to the task so far. But if it blows, I have another available for £250 about $380 dollars with only 20,000 miles on the clock so I'm not really concerned.

brian

JUSTgotMINE 10-08-02 08:33 AM

So where can you get the torque converter and can you use the 98+ model ecus in the 93-95 models?

BNA_ELLIS 10-08-02 10:18 AM

I believe the wiring harness for the post 96 ecu is different to a pre 96 so would not be compatible, but don't qoute me on that. Reason I say that is the pre 96 are 8 bit post 96 are 16 bit, I think thats the same reason why you have to specify which apexi pfc you buy because pre 96 are 8 bit post 96 are 16 bit. There numerous changes on post 96 models in how it runs. What I don't know is if all of the changes as far as tuning & performance is concerned is just down to the ecu or more than just the ecu. Thats why I can't tell you if a newer ecu will work on an older car apart from the wiring harness..
You'll have to check with an rx7 tuning guru to verify that one..

Brian


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