Supra Forums banner

1 - 9 of 9 Posts

·
Now...Whitesupra94
Joined
·
3,249 Posts
Discussion Starter #1
ok guys, well im sure you've at least seen something of my drager post. seeing as this will most likely apply to other exhausts as well as the Drager , i thought id make a new thread.

anyhow...in stock form, when i floor my auto na 93.5 mkiv, it would shift right at 6k rpms, at ~36 mph. with apexi power intake and hks drager exhaust i decided to see whats the deal on power. so i floored and noticed something really strange, or at least strange to me. the car shifted short, at 5600rpms, BUT at the speed of ~36 mph. what exactly does that mean. i take it to mean that im making more power at less rpms...but heres the tricky question...
does that technically im "redlining the gear" at 5600 ? what is the highest possible speed that first gear will go? if i put it in manu and let it rev up to near the redline(rather than the 5600 shift in auto)...would that mean i could go somewhere near 43mph(or at least a few more mph's) since i can make the same mph at less rpms? or would that mean that first gear is obsolete after that rpm mark? does this make sense to anyone?

an intake and exhaust couldnt make a tach and speedo off could it?
thanks
please help, im confused.
Bob
basically what im asking is is my first gear slightly extended in mph's due to making the same speed at lower rpms?
 

·
MKIV TT Sell-OUT
Joined
·
176 Posts
maybe you should go out there and try it again.. theoretically, intake/exhausts should let your car reach 36mph in less time, but not lower rpms...

and yes, you can go past 5600...why does it shift at 5600-6000 anyways?

mine goes waaaay past that, more like 6500-6800 when i floor it
 

·
Now...Whitesupra94
Joined
·
3,249 Posts
Discussion Starter #3
stang2supra said:
maybe you should go out there and try it again.. theoretically, intake/exhausts should let your car reach 36mph in less time, but not lower rpms...

and yes, you can go past 5600...why does it shift at 5600-6000 anyways?

mine goes waaaay past that, more like 6500-6800 when i floor it
ive tried it 3 times in the past few days. once i got it past 6, the other time 58, and this time 5400. but i hit 36 at 5400. i believe it has to do with the torque loss associated witht he dragger, gain HP but i believe you lose quite a few tq. isnt tq what determines how quickly you rev? and hp is more like power and it more imortant at higher speeds? alot has changed since i put on the dragger and i think its cuz of the 95mm piping. the loss of backpressure, ya know..? less resistance. when i had just the air intake my rpms went UP(a few hundred) because more air created more backpressure. (or thats the only explanation i can come up with)
HERES WHAT I MEAN:
EXAMPLE 1. stock form, the auto would always shift at around 6200 in first. would run 2700rpm at 60.
EXAMPLE 2: just the air intake, the car held in each gear longer, usually it shifted out of first at or around 4k, rather than just above 3k stock.
EXAMPLE 3: air intake and 95mm drager exhaust. car would shift usually just above 2k rpms in first, and always below 3 under "my" driving. with "real" normal driving, (i tend to give it alittle bit more gas then "normal" driving) the car shifts at or even below 2krpms. and when i usually drive now rpms are in the mid1-mid 2krpms range compared to 2.5k-3.5k with just intake. so rpms HAVE BEEN affected in some way or another.
but i believe thats do to power. i mean if u can do the same speed with less rpm...that wold equal more power to each rpm....right?:)
why its shifting out so early, i dont really know. but im guessing the cars auto tranny computer recognizes speed and not rpm when judging the shift, that is what would make sense for what its doing. but, judging what has happenend to my car, that means if i use "manu" mode then i will be able to get a few extra mph's out of each gear right?
thanx
Bob
 

·
Now...Whitesupra94
Joined
·
3,249 Posts
Discussion Starter #4
correction...

every time i said 5400 rpms, i meant to say 5600, sorry about that.
54 means 56 in the previous post. :D
 

·
Back in Long Island =)
Joined
·
1,449 Posts
reset your computer and it will shift the same as being stock just it will get up to speed faster . The computer just has to learn that setup airflow /exhuast so it will shift and perform right.~Hope this helps . the computer learns the setup of your car the first bout 15mins of driving. it will setup the right air fuel ratio and it will adjust for correct shifts under full throttle. figure it like this at 5600rpm you car has as much if not more airflow and less retrciton compared to a stock intake exhuast meanig your computer is running your car like you have the stock airfliter airflow thats why it shifts early. ~Xdreamer on and change your fuel filter if it hasnt been changed in a while.

oh and i redline at 7200ish rpm in like 2months it will be 8k redline :)
 

·
Now...Whitesupra94
Joined
·
3,249 Posts
Discussion Starter #7
Xdreamer said:
reset your computer and it will shift the same as being stock just it will get up to speed faster . The computer just has to learn that setup airflow /exhuast so it will shift and perform right.~Hope this helps . the computer learns the setup of your car the first bout 15mins of driving. it will setup the right air fuel ratio and it will adjust for correct shifts under full throttle. figure it like this at 5600rpm you car has as much if not more airflow and less retrciton compared to a stock intake exhuast meanig your computer is running your car like you have the stock airfliter airflow thats why it shifts early. ~Xdreamer on and change your fuel filter if it hasnt been changed in a while.

oh and i redline at 7200ish rpm in like 2months it will be 8k redline :)
how do i reset my computer and is there any risk of making the car run funny by doing so?
 

·
Now...Whitesupra94
Joined
·
3,249 Posts
Discussion Starter #8
with the way its set up now...im getting really good mpg's...when all is said and done...i think it'll be stock figures or even alittle bit BETTER THAN STOCK MPG'S. so i dont really wanna change that. during most normal driving im between 1.5 and 3k rpms..and the pull is fine. the only thing was when i floored it. maybe the car wasnt quite warm enough. it had run about 45 minutes of driving, then the car was off for about an hour...in 45 degree temp. so maybe it just wanted to warm up alil bit first. BUT I NEVER reach the redline in first gear when floored. usually 6300 tops. usually in second i get to 6700.
unfoutunately im away for the weekend. [email protected] highschool fieldtrips. actually it might be kool im going to DC for the cherry blossom festival. :rolleyes: any supras wanna come down and visit me? ill be supraless though.

anyhow ill let you know my mpg's and what is up with the shifting after i get back and play with it a bit.
thanks guys
Bob
 
1 - 9 of 9 Posts
Top