Optimal Shift Point?
Optimal Shift Point? I've been doing some research about the optimal shift point of cars. It sounds to me like the best point to shift at is when the engine reaches max tq. but our cars hit may tq at like 5g's i think their max hp is at like 6500. (na I/H/E). you would want to shift a little earlier before redline in the lower gears for tq cause tq moves the car initialy. but in 3&4 you would want to go as high as possible because HP picks up the slack at higher gears Right? So im guessing shift 1 2 at like 6500-6700 to drop the next gear into or close to max tq and 3 &4 at 6900-7gs for max hp. Im not stating this as a fact it's just a guess.
Imput? what do you feel suites you? which shift method do you use? Controled smooth shift at high reves or power shift? Holla
Imput? what do you feel suites you? which shift method do you use? Controled smooth shift at high reves or power shift? Holla
Originally Posted by HyaBoosta
So im guessing shift 1 2 at like 6500-6700 to drop the next gear into or close to max tq and 3 &4 at 6900-7gs for max hp.
you shift at 6500-6700 when you want to race. it's not a regular shift point.
ok...our VTEC engage at approx. 3000rpm.....and based on the book....the best shift point is at 3000rpm....this is my guess, because on that book, there's a list of shift point at certain MPH.....and if you check them, all shift at 3000RPM...
usually, i shift at 3000-3500rpm...
so, what do you want from ur car? MPG or zoom-zoom (performance)?
Hm...oh wait, it seems like ur talking about optimum, eh?
yeah, it that case...i think 6500-6700 is the RPM....don't go over redline though...not good for "your" health...
Joined: Jul 2002
Posts: 13,151
Likes: 3
From: Washington DC
Rep Power: 424 
You gotta look at the power curve. If its as flat as Kansas, then you'll want to go for as long as you can. If it peaks and dies, then you'll want to shift just after it peaks so you can stay on the upslope between max torque and max HP. I think the car makes max HP at about 61 or 62 and max Tq at 55. From looking at the graphs I've seen for this car, it shoots up then dies. So basically, you're gonna need to look at the gear ratios and figure out where you'll be if you shift at X RPM or if you wait longer. I do know it dies before the redline. I'd say no higher than 6500... just given that you're going to want to go back down a little below max TQ since they're so close together.
Want to get it right, get an accelerometer. At some point, you'll get a max acceleration rate and then it'll die off (while remaining positive). So find max acceleration, and shift there.
Want to get it right, get an accelerometer. At some point, you'll get a max acceleration rate and then it'll die off (while remaining positive). So find max acceleration, and shift there.
so by shifting around 6500 in the next gear i would be falling into gear just short of the peak tq and pull harder than redline right? but i would want to run it up higher in 3 & 4 right?
On vtec engine, which kicks it in on high rpms, is usually one of the best way to utilize the speed capability of the car. Many honda/acura drivers I've seen race dont usually use the vtec to their advantage. Granted the vtec isnt turbo but using it will boost your speed "slightly" enough where it'll make a difference.
Registered!!
Joined: May 2004
Posts: 734
Likes: 0
From: 626
Rep Power: 0 If I were to race my stock LX, then I think I would wanna shift 6,100. That RPM is where the HP peaks. The only reason that I could think of why would you wanna shift at redline is that if you shift slow. I know the RPM drops at least 500rpm when I shift. Now, if I wanted to stay at my peak HP, then it should remain at or no less than 6,100 RPM. I believe I am not making any more HP even if I hit 8K rpm (If thats even possible on stock engine). Shifting higher than 6,100RPM is to anticipate any drop in RPM when shifting to higher gear.
Registered!!
Joined: Jun 2004
Posts: 14
Likes: 0
Rep Power: 0 
Here's how I would do it:
Gear 1 : Shift @ 5,000 RPM's
Gear 2 : Shift @ 5,000 RPM's
Gear 3 : Shift @ 6,500 RPM's
Gear 4 : Shift @ 6,500 RPM's
Through 1st and 2nd gear there is no need to scream it past your peak TQ. Your car won't be making any torque past that number. Keep in mind it's the torque that makes your car accelerate. With that being said, I wouldn't start holding it to my peak HP until the last two gears. At that point your car should be going pretty good and you will need the horsepower for top end.
FYI: I created those shift points off the peak HP/TQ ratings for my car:
Peak HP: 6,100 RPM's
Peak TQ: 4,500 RPM's
Gear 1 : Shift @ 5,000 RPM's
Gear 2 : Shift @ 5,000 RPM's
Gear 3 : Shift @ 6,500 RPM's
Gear 4 : Shift @ 6,500 RPM's
Through 1st and 2nd gear there is no need to scream it past your peak TQ. Your car won't be making any torque past that number. Keep in mind it's the torque that makes your car accelerate. With that being said, I wouldn't start holding it to my peak HP until the last two gears. At that point your car should be going pretty good and you will need the horsepower for top end.
FYI: I created those shift points off the peak HP/TQ ratings for my car:
Peak HP: 6,100 RPM's
Peak TQ: 4,500 RPM's
well i went out to the races and beat a 98 integra gs and 94 hatch both with bolt on's
and i shifted 1 & 2nd at 6gs and 3 & 4 at 6500. i was pulling nicley too so i am sure that earlier shifting at peak tq and hp works.
and i shifted 1 & 2nd at 6gs and 3 & 4 at 6500. i was pulling nicley too so i am sure that earlier shifting at peak tq and hp works.
Registered!!
Joined: May 2004
Posts: 244
Likes: 0
From: San Diego, CA
Rep Power: 0
Originally Posted by Tuning 101
Here's how I would do it:
Gear 1 : Shift @ 5,000 RPM's
Gear 2 : Shift @ 5,000 RPM's
Gear 3 : Shift @ 6,500 RPM's
Gear 4 : Shift @ 6,500 RPM's
Through 1st and 2nd gear there is no need to scream it past your peak TQ. Your car won't be making any torque past that number. Keep in mind it's the torque that makes your car accelerate. With that being said, I wouldn't start holding it to my peak HP until the last two gears. At that point your car should be going pretty good and you will need the horsepower for top end.
FYI: I created those shift points off the peak HP/TQ ratings for my car:
Peak HP: 6,100 RPM's
Peak TQ: 4,500 RPM's
Gear 1 : Shift @ 5,000 RPM's
Gear 2 : Shift @ 5,000 RPM's
Gear 3 : Shift @ 6,500 RPM's
Gear 4 : Shift @ 6,500 RPM's
Through 1st and 2nd gear there is no need to scream it past your peak TQ. Your car won't be making any torque past that number. Keep in mind it's the torque that makes your car accelerate. With that being said, I wouldn't start holding it to my peak HP until the last two gears. At that point your car should be going pretty good and you will need the horsepower for top end.
FYI: I created those shift points off the peak HP/TQ ratings for my car:
Peak HP: 6,100 RPM's
Peak TQ: 4,500 RPM's
Raceway Park Track Tech.
iTrader: (1)
Joined: Jun 2001
Posts: 2,693
Likes: 0
From: Old Bridge, New Jersey, US
Rep Power: 329
Originally Posted by Tuning 101
Here's how I would do it:
Gear 1 : Shift @ 5,000 RPM's
Gear 2 : Shift @ 5,000 RPM's
Gear 3 : Shift @ 6,500 RPM's
Gear 4 : Shift @ 6,500 RPM's
Through 1st and 2nd gear there is no need to scream it past your peak TQ. Your car won't be making any torque past that number. Keep in mind it's the torque that makes your car accelerate. With that being said, I wouldn't start holding it to my peak HP until the last two gears. At that point your car should be going pretty good and you will need the horsepower for top end.
FYI: I created those shift points off the peak HP/TQ ratings for my car:
Peak HP: 6,100 RPM's
Peak TQ: 4,500 RPM's
Gear 1 : Shift @ 5,000 RPM's
Gear 2 : Shift @ 5,000 RPM's
Gear 3 : Shift @ 6,500 RPM's
Gear 4 : Shift @ 6,500 RPM's
Through 1st and 2nd gear there is no need to scream it past your peak TQ. Your car won't be making any torque past that number. Keep in mind it's the torque that makes your car accelerate. With that being said, I wouldn't start holding it to my peak HP until the last two gears. At that point your car should be going pretty good and you will need the horsepower for top end.
FYI: I created those shift points off the peak HP/TQ ratings for my car:
Peak HP: 6,100 RPM's
Peak TQ: 4,500 RPM's
With the way you guys shift it no wonder why your times suck. 
You must use all of the rpms in each gear so when you go into the next gear your either at peak power or almost there. Also practice at your local track. Safer then testing it out on streets. 
Registered!!
Joined: Jul 2003
Posts: 51
Likes: 0
Rep Power: 0
Originally Posted by LazyDog01
This is great if your driving around your grand parents around. With the way you guys shift it no wonder why your times suck. You must use all of the rpms in each gear so when you go into the next gear your either at peak power or almost there. Also practice at your local track. Safer then testing it out on streets.
With the way you guys shift it no wonder why your times suck. You must use all of the rpms in each gear so when you go into the next gear your either at peak power or almost there. Also practice at your local track. Safer then testing it out on streets.
right ......i always shift at 6800 ( max rpm) 
. But you get the idea 
cuz my rpm seams to reach his max at 6800 
well, i always thought you redline every gear!? but for some reason this VVV sounds interesting.
(quote)
well i went out to the races and beat a 98 integra gs and 94 hatch both with bolt on's
and i shifted 1 & 2nd at 6gs and 3 & 4 at 6500. i was pulling nicley too so i am sure that earlier shifting at peak tq and hp works.
(quote)
well i went out to the races and beat a 98 integra gs and 94 hatch both with bolt on's
and i shifted 1 & 2nd at 6gs and 3 & 4 at 6500. i was pulling nicley too so i am sure that earlier shifting at peak tq and hp works.
take the time to floor your car and feel for the power. and listen to the exhaust. after about 6500 it's gonna start to feel the same and alot less pull and shifting becomes harder.i used to run every gear to redline for a long while and now that i tried this method i noticed a difference and I think 6500 is the money shot
Registered!!
Joined: Apr 2004
Posts: 178
Likes: 0
From: Clearwater, Florida
Rep Power: 0
Originally Posted by HyaBoosta
take the time to floor your car and feel for the power. and listen to the exhaust. after about 6500 it's gonna start to feel the same and alot less pull and shifting becomes harder.i used to run every gear to redline for a long while and now that i tried this method i noticed a difference and I think 6500 is the money shot
Raceway Park Track Tech.
iTrader: (1)
Joined: Jun 2001
Posts: 2,693
Likes: 0
From: Old Bridge, New Jersey, US
Rep Power: 329 ok let me explain into more detail. Reason why you should go to redline.. Is to use all the hp and torque you can in each gear. So when you go into the next gear your either at max hp and torque or almost pushing it. For you quatermile guys. If your driving a stock civic. Use should be only using gear 1-3. If you cross over 1/4 mile line and your in 4th gear. Your time gunna suck. Reason why you should not go into 4th, 3rd gear redlines around 86-89 mph. Stock ex goes to about 84-88 with a good driver. So if you waste more time to drop it into 4th. Your gunna add time to your ET. If you have any questions go nuts and ask. or seek 
never said you don't redline 3rd. If you redline 1st or 2nd then when you go to the next gear your out of the peak tq. so all thats pushing your car is mostly hp. in third gear i would redline it too. but in 1st and second to get the car moving , you need tq and by mid 3rd you've got good speed going so hp all the way from there. ya feel me?
Autocross Junky
Hey! Look At Me!! I'm a Supporting Member!!
Joined: Oct 2002
Posts: 7,211
Likes: 0
From: Las Vegas, Nevada, US
Rep Power: 380 The thing you need to look at is the torque curve and your gearing. that will tell you your best RPMs to shift.
I'll make an example for ya.
Evey engine has a torque curve, and it is just that a curve. meaning it will peak at a certin RPM and then begin to drop. As the Torque curve drops, you begin to acclerate at a decreasing rate (Your still accelerating but at a lower rate). Once your torqe curve has droped to the point where your accelerating in this gear = the accleration in the next highest gear then that is your best shift point. WHy? Because if you leave it in the current gear you will be accelerating less then if you were in the next gear, and being in the next gear allows you to go back throuhg that torque curve to get maximum acceleration.
Where is that on our cars..... I dont know, you need to get your car Dynoed, and figure out the gearing on your car. That will tell you where you should shift for best acceleration.
I'll make an example for ya.
Evey engine has a torque curve, and it is just that a curve. meaning it will peak at a certin RPM and then begin to drop. As the Torque curve drops, you begin to acclerate at a decreasing rate (Your still accelerating but at a lower rate). Once your torqe curve has droped to the point where your accelerating in this gear = the accleration in the next highest gear then that is your best shift point. WHy? Because if you leave it in the current gear you will be accelerating less then if you were in the next gear, and being in the next gear allows you to go back throuhg that torque curve to get maximum acceleration.
Where is that on our cars..... I dont know, you need to get your car Dynoed, and figure out the gearing on your car. That will tell you where you should shift for best acceleration.
zzxzx I've been trying to say this the whle thread. thank you for making everyone understand. Redlining every gear is not the fastest way to drive.
From most bolt on ex's i've seen average tq peak off at about 4700-4900rpm
and peak hp at about 6500 rpm.
Last edited by HyaBoosta; Jul 8, 2004 at 05:23 PM.
Why is my vagina bleeding?
iTrader: (1)
Joined: Mar 2004
Posts: 3,582
Likes: 0
From: Montreal
Rep Power: 304 Would it be best to change gears between 4800rpm(114@4800) and 6300rpm(127@6300)?
Zzyzx. I found a graph from AEM' website
http://aempower.com/pdf/dyno/24-6100...Civic%20Ex.pdf
could you check it out? Does have any info that can tell us when we should shift?
Zzyzx. I found a graph from AEM' website
http://aempower.com/pdf/dyno/24-6100...Civic%20Ex.pdf
could you check it out? Does have any info that can tell us when we should shift?
