RiceBurner

What is the current wisdom for the most efficient type of shifting when "hypothetically drag racing" on the open road. It seems that gate shifting is the norm for the track??????

peiqinglong

Gate shifting if you know what your doing and have lots of practice since this method has the highest chance of damage to your engine. On the freeway, you can only downshift one gear via the gateshifting method...I would rather go with teh SS on the freeway if you need the power. On the other hand, drag racing on the streets, gate shift only if u know what ur doing. Practice it first, get a feeel for your car.

Disclaimer: Street racing should be kept to a minimial as possible and the above post does not reflect the poster's attempt to justify street racing or encourage it, but rather to answer the question posed

asiankidd

ss is the worst invention i have ever seen atleast on the 5speed tl, with no use of 1st gear i find it a epitome of pos slushboxs, whenever i get the need to race i use the gate method, as a follow up on wat peiqinglong said, you will CAN cause more wear on your engine as you will be pushing it harder, near redline, but you certainly cant!!! damage your engine unless you mean to but even at that its hard, the engine has its own rev limiter, and lets say you were crusing the freeway at 80 and gate shifted into 1st it will ONLY DROP to the LOWEST GEAR it can with OUT over revving the engine, in other words IT WONT GO INTO 1ST!!!, i think its just as safe to use as auto, but if you wanna be revving at 6900rpm in first for 15 mins of course you might do some premature wear and damage, none the less thats your bad.....

JON

PeterUbers

iTrader: (1)

it's not the engine you need to worry about ...

the Type S engine is very comfy revving at 6000 rpms for a modest amount of time.. it's your auto tranny that can't drop into a low gear when it doesn't want to... it's not built like a manual... there are many more parts and viscous couples/clutch packs .. that are involved in ONE shift...

SS at least is intelligent enough (supposedly) to mitigate your input so as not to overstress the tranny....

power3dfx

i said it before and will say it again. the entire car is built to prevent you from damaging. the tranny design is one of the best, if it wasnt for the failures, i would definately take it over lexus trannies. its overall response and shifts are excellent. the ss mode is actually very intuitive.
have any of you guys driven another tiptronic tranny. almost all of them suck. they dont get as much control as we do.
1) Many "manumatics" will shift if you hit rev limiter, ours doesnt
2) We dont get control over 1st gear, but the computer will shift close to redline in ss mode anyways
3)The car stays in the gear you tell it to go in next. Some sportshifts will downshift if you floor it, defeating the purpose of the gear selection i.e. lexus e-shift
4) Other than SMG, this is almost closest to a manual.
For straight drag racing, i would say that gate shifting may or may not help.
If you look at the power curve for the type s engine, above 6800 rpm, the power really drops. I think it may be better to just leave it in ss, you might not hit the rev limiter or even rev up to it in 1-2 shift, but you also avoid the "dead" area.
Who ever made the theory "shift at redline"??????

PeterUbers

iTrader: (1)

buddy, the reason you wanna shift at 7100 rpms in gate-shift mode is so the tranny'll drop you at a higher rpm at the next gear... hence why most *shift* points in n/a cars are AT redline. It varies w/ cars that are turboed b/c of the variance in rpms of the turbo to the rpms of motor. You're quite right that the last couple hundred rpm's on the tach are pretty useless in terms of accelerating the vehicle anymore, but it's more valuable to be in the sweet spot in the next gear to make up for the time it took to shift.

ShaguraTL

That's why god blessed the world with close ratio gearboxes. Unfortunately Acura only puts them on the RSX-S and CL-S 6spd.

power3dfx

peterubers, you are right in one part about the higher rpm in next gear. after some thought, here is my final conclusion:
1) When shifting at WOT from 1-2-3, i think we shouldnt exceed the 6900 rpm. Since the gear ratios are closer in 1-2-3, i think it is more beneficial to shift *earlier. This will still leave you in vtec range, and you can start from a better rpm range and work way up.
2) Now, this is where you are absolutely right. When you want to shift into 4th, you need to prepare! Therefore, this is where you would want to maximize rpm's before shift.
Good observation nonetheless peter.

PeterUbers

iTrader: (1)

Power --

Check out the ratios of the Maxima ('97-'03) 4-spd auto.. the first 3 gears are laid out nearly identically to ours (final drive is also very similar) .. though, they don't tout the Max as having a close-ratio auto tranny. It's interesting about the TL-S tranny, mated to this engine, the TL-S auto has more "barK" than bite.. i.e. .. it's revs high and is loud, but you're really not going as fast as you may think. Consider this also... the achive the PEAK performance of the CL-S 6-spd.. (an even CLOSER ratio gear box as you'd have to agree) .. the max performance is still achieved by shifting at 7100 rpms... just food for thought, but I like your thought process.

SimTypeS

Learn to gate shift. That is all.

edgalang

Almost...but not entirely true.

Given these values...

4800 = VTEC engagement
6900 = Engine max RPM
215/50/17 = Tire size

4.428 = Final drive ratio
2.563 = 1st
1.551 = 2nd
1.021 = 3rd
0.653 = 4th
0.470 = 5th

Shifting @ redline (6900 RPM) will leave you in...

1->2 = 4.17k RPM @ 44.6 mph
2->3 = 4.54k RPM @ 73.8 mph
3->4 = 4.42k RPM @ 112.1 mph
4->5 = 4.97k RPM @ 175.2 mph

* Please note...mph does NOT account for aerodynamic drag! (actual speeds are slower)

So...back to my point...there's no gear shift that will leave you in the high VTEC range. The 4->5 shift doesn't count since you'll be topped off at ~147 mph anyways.

PeterUbers

iTrader: (1)

Sorry man, but the point you were initially trying to make w/ your mathematical logic isn't helped by your mathematical logic. The variances that you guys are considering are way too slight to notice on the tachometer (i.e. VTEC "range") and what not .. I suggest those who disagree w/ gate-shifting do several runs w/ and w/o gateshifting at the track as I did to realize the difference in your ET. Until you run your car at the track, these numbers are meaningless .. nothing more than another reason to argue a technicality on the forum -- peace

(ed & power -- i don't know if you've run your cars w/ both methods .. shifting at 7100 vs. 6900 .. and if you have, no offense .. so pls. don't come back w/a flame.)

edgalang

Your response does NOT make sense. Perhaps you misunderstood mine, but all I was trying to say was that no matter where you shift (6.9k vs 7.2k), technically you won't be in "VTEC" since it engages @ 4800 RPM. I was merely correcting what power3dfx was saying on a previous post before newbies start believing it.

As for "my" mathematical logic...it's FACT. I cannot take credit for anything that is simply...is. I am not here to debate the topic of "gate shifting vs SS"...I was merely presenting FACTS, which is already given to us by Acura.

You guys (PeterUbers & power3dfx) can debate all you want...but my point still stands.

PeterUbers

iTrader: (1)

Ed .. trust me, I meant no offense -- but practically speaking, the torque band on the Type S begins at 3500 rpms... so VTEC or not, you're still better off, IMHO, being dropped into a higher rpm to be in the sweet spot of the torque band.. I apologize if I mistakenly stated "sweet spot of VTEC" .. b/c obviously, as your information DOES prove .. our gearing is not nearly that close so as to drop us in VTEC by redlining in each gear. I don't even think the 6-spd will let you do that.

Our torque band is 3500-5500 .. correct? The higher we are in this, my theory, the better off you are in terms of peak acceleration. Just a theory, and it's bound to be refuted.

edgalang

OK..so after re-reading both our posts, it's clear to me that we are still not on the same page. I'm not discussing the topics of "SS vs GateShifting" nor am I even involved in the topic of "which RPMs we should shift at". I'm mearly stating facts.

But, to clarify all other confusion, let me restate my example in english (maybe the arrows and #'s were too confusing).

Say you are stopped at a light and you floor the car at first gear (SS or gateshift...it doesnt matter).
Engine RPMs are going up fast and you basically redline each gear.
By the time 6900 rpm hits (still at first gear) you are going about 45 mph.
2nd gear catches and your engine drops down to 4.2k rpm (still going 45 mph).
You continue to floor through second untill you reach redline again (6900 RPM), but now you are going 74 mph.
You shift to third and your engine drops down to 4.4k rpm (still going 74 mph). And so on and so on.

My point had NOTHING to do about which RPM you should shift at...nor did it have anything to do with using SS or gateshifting.

I was mearly stating...if you shift at redline (6900 rpm ONLY) through EACH gear, that your RPMs would drop down to XYZ after each shift. Thus...correcting what power3dfx said earlier about gears 1-2-3 dropping you in the "VTEC" range after each shift.

Which...if you look at the numbers given, the strongest shift would be between 2nd and 3rd. But...even then, that would only leave you @ 4.6k, which is STILL below the VTEC engagement point @ 4.8k. Again, my posts were only meant for power3dfx.