FI+gearing

[Cronic]

Here's a good link to an explanation as to WHY longer gears are NOT better for turbo. My tuner John(Vapor) explains it well here.

http://www.tamparacing.com/forums/sh...threadid=96302

This should dispell all myths as to WHY long gears are NOT better.

[PWMAN]

Still trying to ''educate the masses'' huh? Well you and your buddy are WRONG. ME and SHHHH_BURN_ have track times to prove it. Give me this guys Email address, I want to talk to him.

[Neutrino]

well i could not access that link since my university's firewall has issues with it....i hate it services.....


anyway...a car's gearing should be designed to keep a car in its strongest part of the powerband......so a car wil a super short optimum power would benefit from shorter gearing....while a car(as a viper for example) with torque all over the place will not benefit as much from shorter gearing since you'll have to change gears way less....so i say the best setup is to make the gearing as long as alowed by the engine's optimal powerband......


just saying that FI and longer gearing are bad togheder is overgeneralising...it really depends on the type of engine....


another factor that should be taken in consideration is the type or racing you do....some circuits with many tight curves will ask for short gearing....while courses with long stretches will favor long gearing.......so overgeneralising is no good......

[Cronic]

Nice explanation.

[ssshhhh (_burn_)]

soo....


if a turbo car has a powerband like a n/a car. it uses short ratios to get it down the track faster.
if a turbo car has a nasty powerband like mine then it uses a long ratio tranny to get it down the track faster.

[Cronic]

No. You want the gearing (weather short or long, it's irrelevant) to drop you right at the top of your power curve. Therefore making the most power throughout the run.

[civicgsr_T4_60-1]

Ok here we go, i'm another guy here that believes in shorter gears for higher reving cars like our honda's. It's very simple, there isn't that much good info over here on this board about tranny and gearing selection. Honda-tech, is a much better place for this info. But all in all if you have a stock rev limiter, You might as well just go with your stock tranny. But if you have a higher rev limiter, if you have a b series motor, the B16 tranny would be your best choice. It will get you to higher rpms, where you will make your power. This is for drag racing only. If you want to do top end runs, yes, you will obviously want to run longer gears.

"if a turbo car has a powerband like a n/a car. it uses short ratios to get it down the track faster.
if a turbo car has a nasty powerband like mine then it uses a long ratio tranny to get it down the track faster."-shhhh burn

Well, if you have a nasty powerband that's your fault for not tunning it properly or running the right fuel setup. You would do much better with a shorter geared tranny.

"Still trying to ''educate the masses'' huh? Well you and your buddy are WRONG. ME and SHHHH_BURN_ have track times to prove it. Give me this guys Email address, I want to talk to him."-PWMAN

What are your track times, have you tried a shorter geared tranny, if so, what was the difference in time, was it the same track, and what was the difference in the whole drive down the track.

[PWMAN]

Originally posted by civicgsr_T4_60-1

What are your track times, have you tried a shorter geared tranny, if so, what was the difference in time, was it the same track, and what was the difference in the whole drive down the track.

In my Daytona the stock tranny is an A525 (turbo I, non intercooled, 146 HP stock) with this gearing-
1st-3.29
2nd-2.08
3rd-1.45
4th-1.04
5th-.72
final drive-3.87
The 525 was not beefy at all, very weak and was not meant for more than 225 HP.

The tranny I put in (from a turbo II, 174 HP engine) has this gearing-
1st-3.00
2nd-1.89
3rd-1.28
4th-.94
5th-.71
final drive-3.85
The 555 tranny is the best and most sought after tranny for Daytona's, now I wonder why Chrysler put in a taller gearing tranny in their performance cars. Maybe because longer gearing is better for turbo's????? No that can't be it, yeah those idiots that make over 100K a year don't know what their doing. Is that it? No I don't think so.

I went from running a 15.2 to a 14.8. No other mods were made but the tranny. Since then I've done a few things to get to a 14.5. Next step is a full turbo II conversion, then I might break 13's. Mostly because the setup of a turbo I has no intercooler, a turbo II does. But I'm going to put a huge front mount on so it will be better than a stock turbo 2 intercooler.

You might want to ask SHHHHH_BURN_ about his times. He did 11.8 on his B16 tranny, then swapped to an LS and went 10.8. Then he did some more tuning and is down to 10.3.

[Cronic]

I seriously can't believe your still tryint to argue this... Please end yourself. It has already been established. It's not about how long or short your gears are. It's about the powerband. STFU now.

[edman24]

i say you people who are fighting over this should just build your damn motors the way you think is best. my car is an NA LS/Vtec. i have a b16 tranny. it kicks ass for me. so i suggest build your own motors and then race to see who is faster. then you can have bragging rights and talk all about your wonderful tranny.

[ssshhhh (_burn_)]

Originally posted by civicgsr_T4_60-1
Ok here we go, i'm another guy here that believes in shorter gears for higher reving cars like our honda's. "if a turbo car has a powerband like a n/a car. it uses short ratios to get it down the track faster.
if a turbo car has a nasty powerband like mine then it uses a long ratio tranny to get it down the track faster."-shhhh burn

Well, if you have a nasty powerband that's your fault for not tunning it properly or running the right fuel setup. You would do much better with a shorter geared tranny.

"Still trying to ''educate the masses'' huh? Well you and your buddy are WRONG. ME and SHHHH_BURN_ have track times to prove it. Give me this guys Email address, I want to talk to him."-PWMAN

What are your track times, have you tried a shorter geared tranny, if so, what was the difference in time, was it the same track, and what was the difference in the whole drive down the track.

i wasnt talking about nasty as in bad. nasty as in it starts reaching for 500 at around 4500 very quickly. and....my car isnt a very high reving engine imo. it stops making power at 8500. it CAN rev to around 9500 now but i usually dont get it there. it just depends on the weather that day. and as i stated in another thread like this. yes i have run a stock ratio b16 tranny on my car. i had a best time of 11.8@122. i ran a whole second faster with the same motor 2 months later with a 91 ls tranny. the track conditions were better but not a second better. the ls tranny pulled better early on but DID slack a little bit in fifth of course. now im running a rebuilt ys1 and im prefectly happy with it.

[ssshhhh (_burn_)]

Originally posted by Cronic
I seriously can't believe your still tryint to argue this... Please end yourself. It has already been established. It's not about how long or short your gears are. It's about the powerband. STFU now.

exactly!! WE established that point .we said from the beg that it depends on your powerband. and i havnt seen too many n/a cars with powerbands like turbo cars......

Originally posted by Cronic
Alright after a lot of thought, and theory on the subject I decided to post some findings. Being as gearing is not a subject Ive touched on a great deal. I figured it was a good opportunity to learn stuff, and I think I have.
This is the reason that people say shorter is better for n/a: Your powerband usually is very broad, starting say at 2 or 3k RPM, and carrying over to 7-8 or even 9k RPM, You will want to take the mechanical advantage and get the highest tq multiplier possible for this, IE, shortest gears. Now You don't want to go too short, because you'll end up running out too soon. If you go too long, IE drop below your powerband, you'll never go anywhere because it's taking too long to get back into the powerband.

Now. FI cars _GENERALLY_ have very steep and high powerbands. Say my powerband starts at 4200rpm goes all the way to 8k RPM, I will want a tranny that will drop me just after that 4200rpm, any higher and I'll not get full use of the powerband. Hence recieving a slower ET/MPH. This will also put some crazy stress on the drivetrain components :P but that's a different story.

So what Im basicly trying to say is that Longer isn't always the best solution for FI, and shorter not always the best solution for N/A. It all depends on your powerband. You don't want your tranny to drop you below your power curve. You want to be right smack dab in the middle of it, or at least a good portion of the way in it.

I believe burn said he went from a B16, to an LS tranny... that's a HUGE difference in ratios. I bet all things remaining equal, if you put a GSR tranny in there, and maybe even an ITR final drive, you would drop another 2/10ths off your ET. Effectivly shortening your gears slightly, but NOT as short as the B16.

and you just agreed with what we have been saying for the past 2 days....just in your words. AND i agreed with you. in fact.....i do have a shorter final drive on my ys1.

[civicgsr_T4_60-1]

agreed, the powerband does make a huge difference. But shorter is better

[ssshhhh (_burn_)]

Originally posted by civicgsr_T4_60-1
agreed, the powerband does make a huge difference. But shorter is better

yep...just not too short. i consider a type r tranny (or b16) too short for my application because of the lower gears.

[civicgsr_T4_60-1]

That's my problem right now. I want a B16 tranny for when i bump my rev limiter, but i'm afraid i'll be in 5th gear before i cross the traps. I'll see how my gsr tranny does this weekend. If I get into the 10's, i'll stick with it.