6 speed vs. 5 speed acceleration comparison

[trabbic]

^ I've been referring to the 06 Spec.B that has the 5MT.

 

I was using the 06 as an example of how lower gearing does not always yield faster acceleration times.

 

Don't blame the R92s for yet more poor performances. OEM LGTs aren't lighting up the fronts on hard dry pavement acceleration.

 

DID YOU NOT READ WHAT I POSTED EARLIER?!? A STOCK 5MT GT WITH RE92'S WILL SURE AS HELL LIGHT UP THE FRONT TIRES. EVEN ON A PREPARED DRAG STRIP, I HAVE DONE IT SEVERAL TIMES!!!

 

The 06 Spec. gets quicker times despite being heavier and having taller gearing (the 18"s). What might account for that? Could it be greater power? That could definitely account for it.

 

It could be greater power, but show me a dyno of an 06, or get one done yourself the one dyno i can find shows 10 hp more from a cat back exhaust, exactly what you would expect: http://legacygt.com/forums/showthread.php?t=51953&highlight=spec+dyno This is an 07 with a direct overlay to a 05, and it shows gains consistent with a cat back exhaust.

 

Tires can make a big difference, as I have stated several times to you.

 

It is pointless to argue with you, you don't listen to what people say and you just keep spitting out the same BS that you believe to be true. I will no longer reply to you.

[mccorry]

Great post, Trabbic!

[mccorry]

Hmm - looks like if this turns into a car I keep for another 10 years or so, it may get a full 6spd swap just to knock off 1000+ rpms while cruising. It'll be interesting to see if tuned 6spd's net noticably better highway gas mileage.

 

Note that gearing like that nets 90 mph cruising at 3k rpm -- again, very useful and much improved over the 5spd's interstate manners.

 

 

Am I missing something here? I thought the final drive on the 5MT and the 6 MT are BOTH 1:1 ?????

 

How can the 6 spd. give you lower RPM's at speed?

[mccorry]

@ Vimy the troll!

[moviemadness]

1. If redlining every gear is not ideal for the best acceleration on the 05 LGT MT, then when should you shift?

 

2. what is the rpm speed on a 6MT @ 65mph?

[trabbic]

Am I missing something here? I thought the final drive on the 5MT and the 6 MT are BOTH 1:1 ?????

 

How can the 6 spd. give you lower RPM's at speed?

 

The 5th gear on the 5MT is .74 coupled with a 4.10 final drive (or rear end for you muscle car guys ) With 215 17 45 rims and tires 90 mph is at about 3700 rpm. (this is an estimate calculated by my program YMMV)

 

6th in the 07 Spec B is .707 with a 3.9 final drive and 215 18 45's so @ 90 is about 3200 rpm, give or take...

 

Both high gears are overdrive gears, but the 6 speed overdrives more.

[trabbic]

1. If redlining every gear is not ideal for the best acceleration on the 05 LGT MT, then when should you shift?

 

That depends on your car, and what hp you are making, if you are stock a redline shift is probably the best bet.

 

Give me a dyno and I can plug in the numbers and see when my program says to shift.

 

You can also calculate when to shift by graphing the hp or tq at rpm times gear ratio times final drive (i think), and you should get lines on a graph, shift when they intersect and if they don't intersect then shift at redline.

 

2. what is the rpm speed on a 6MT @ 65mph?

 

Should be right around 2300 rpm.

[moviemadness]

how about TDC stage one?

[Vimy101]

I was using the 06 as an example of how lower gearing does not always yield faster acceleration times.

 

 

 

DID YOU NOT READ WHAT I POSTED EARLIER?!? A STOCK 5MT GT WITH RE92'S WILL SURE AS HELL LIGHT UP THE FRONT TIRES. EVEN ON A PREPARED DRAG STRIP, I HAVE DONE IT SEVERAL TIMES!!!

 

 

 

It could be greater power, but show me a dyno of an 06, or get one done yourself the one dyno i can find shows 10 hp more from a cat back exhaust, exactly what you would expect: http://legacygt.com/forums/showthread.php?t=51953&highlight=spec+dyno This is an 07 with a direct overlay to a 05, and it shows gains consistent with a cat back exhaust.

 

Tires can make a big difference, as I have stated several times to you.

 

It is pointless to argue with you, you don't listen to what people say and you just keep spitting out the same BS that you believe to be true. I will no longer reply to you.

 

Here is the thread that seems to have gotten the excuses started:

 

http://www.legacygt.com/forums/showthread.php?t=49189&highlight=Spec.B+dyno

 

This is form the thread that adds credence to more hp and torque which would explain the faster Spec.B times: http://www.legacygt.com/forums/showthread.php?t=46379&page=4&highlight=SPEC+dyno

 

http://www.avoturboworld.com/images/stories/avostories/rallitek_dyno/specb_dyno_001.gif

 

Stop throwing a hissy fit and deal with the evidence.

 

Here is the OP from that thread:

 

Preliminary results are in from a big first day of dyno testing. One of the first vehicles up was the stock '07 Legacy Spec B with the 6-speed manual transmission. After finally running out the tank of the gas it had come with, which we suspect was *not* high octane, it was running much better and smoother. Up on the rollers it went, and we did a total of 5 runs to get everything squared away.

 

Intelligent mode has a definite slowing effect on the car. That is easy enough to tell by the seat of your pants, but it was nice to have confirmation. Maximum boost reached was 9 psi, well under the normal boost levels. Which explained why the power was well under max figures at 159 hp at the wheel. Next up was the normal Sport mode. Normal Sport mode was a surprise, as it also showed the best graph of all modes.

 

I had suspected this. When I attended the first Spec B briefing in Japan, buried in all the facts and figures was the graphs for the throttle response behavior of each mode. Intelligent mode was locked down to a maximum throttle opening of 40%, a large reason for the gas savings. Sports Sharp mode felt livelier because they increased the ramp-up rate of throttle response. What that means is that by the time the actual gas pedal has reached about 50-60%, the throttle is opened to 98%. However, it does not go beyond 98%! The only mode where it does is the normal Sports mode, which was shown on the dyno. Sports mode showed the highest figures, 214whp vs 208whp in Sports Sharp mode. It reached these figures at 15.8psi of boost, vs. 15.5psi in Sports Sharp.

 

Baseline for a new Legacy GT wagon 5-speed which was done today, one day afterwards, was 195whp. Which matches Ralliteks original figures, and is just about right given Subaru's official figure of 250hp at the crank. What is interesting is that the Spec B, while being listed as having the same power as the GT, does indeed have nearly 20 more hp than the standard GT. Given that it is running pig-rich, there is a lot more to be had there with some basic tuning.

 

I'll post the dyno charts a little later today.

 

http://www.avoturboworld.com/images/stories/avostories/rallit_day2/rtek_d2_005.jpg

 

Cheers,

Paul Hansen

www.avoturboworld.com | www.sevenphotos.com

[trabbic]

how about TDC stage one?

 

Here you go, Stage One shift points...

 

I can't remember what my stage one redline was set at, but I put it at 6900 for this test, and you should really shift there for all shift points, except possibly 4-5 shift, which is around 6800 (to close to tell the difference).

 

1 or 2 hundred rpm is not going to make a huge difference. Just shift as close to the limiter as possible.

 

Here is the tq to wheels mapped out by gear to see what I was talking about earlier.

Stage 1 tq graph by gear.pdf

[douglas751]

You guys are all pissing and moaning about nothing, a moot point. Any of these Legacy are fast as hell, comparable to Supercars from the 1980's and they will smoke a muscle car from the 1960s. Why would a second here or a hp there matter anyhow? These are 4 door Japanese cars, these are not race cars. Get real.

 

Go out on the freeway, keep the car in top gear, cruise about 90. Slowly depress the throttle without donwshifting and I bet that very few cars will stay with you up to 130 mph. I have a 1989 C4 Porsche, I am pretty sure that the Legacy is faster in the real world.

 

What more do you want? What more could you want? If you want that anoying woshing sound, then screw around with your intake and I bet your car will be slower.

 

It would be nice to have a sxth gear that is an overdrive so that when driving at 90 mph or so the engine is quieter. That would be nice. Is that not what this thread was about?

 

Good luck.

[trabbic]

You guys are all pissing and moaning about nothing, a moot point. Any of these Legacy are fast as hell, comparable to Supercars from the 1980's and they will smoke a muscle car from the 1960s. Why would a second here or a hp there matter anyhow? These are 4 door Japanese cars, these are not race cars. Get real.

 

Go out on the freeway, keep the car in top gear, cruise about 90. Slowly depress the throttle without downshifting and I bet that very few cars will stay with you up to 130 mph. I have a 1989 C4 Porsche, I am pretty sure that the Legacy is faster in the real world.

 

What more do you want? What more could you want? If you want that anoying woshing sound, then screw around with your intake and I bet your car will be slower.

 

It would be nice to have a sxth gear that is an overdrive so that when driving at 90 mph or so the engine is quieter. That would be nice. Is that not what this thread was about?

 

Good luck.

 

Thank you. Although I don't agree with everything you said. I race my car and a second here or there is a big difference (hell a couple of tenths of a second is a big deal to me).

 

You are correct however this topic is about the 6 speed, and what it will do to acceleration. I was just trying to point out that the acceleration difference between the 6 speed and 5 speed will be minor if it exists at all, and that there are only benefits (minus the cost) to the extra gear, like a better cruise rpm.

 

A lot of posts have been made recently about how the 6 speed will be slower, because of the extra shift. So I just wanted to actually post up some information that had some mathematical backing.

 

Unfortunately this topic was pulled off topic by our friend Vimy... And in my ignorance I fed the troll.

 

But... but... the spec b is the fastest!

[mccorry]

@ Vimy the troll!

 

Still

[deimos]

^ I believe the fastest published OEM 06 Spec.B 1/4 mile time is 13.9 which is quicker than the fastest OEM LGT time if I recall correctly. Lower gearing will get a car into its power band more quickly. The Spec. with its larger diameter wheels effectively has higher gearing and still runs faster times.

 

No.

 

R&T got 5.1 to 60 and 1/4 in 13.7 with the 06 spec. Most other mags got 5.3 and 14.0 1/4.

 

Autoweek got 5.23 to 60 and 1/4 13.9x with stock 05 GT

 

Magazine racing FTL!

[Vimy101]

^ If being labeled a "troll" for poking holes in this site's conventional wisdom using the facts in evidence in this site then so be it. I take it as a compliment.

 

The funniest thing is that once again the LGTs tires are made the scapegoat.

[rudy]

Here is the thread that seems to have gotten the excuses started:

 

Did they dyno a 2007 SpecB vs. a 2007 GT? Again, I think any differences, if there are any, are more likely to come from the minor, 2007 model year changes to the engine versus one car being a Spec and one a GT. Either way, it's moot once it's chipped.

[Vimy101]

No.

 

R&T got 5.1 to 60 and 1/4 in 13.7 with the 06 spec. Most other mags got 5.3 and 14.0 1/4.

 

Autoweek got 5.23 to 60 and 1/4 13.9x with stock 05 GT

 

Magazine racing FTL!

 

13.7, eh? That's pretty impressive. So you are saying that the fastest published times were posted by the 06 Spec.B despite its effectively higher gearing and increased mass.

 

I just wonder why there is such resistance on this site to the idea that the Spec.B is OEM tweaked. It is the simplest explantion after all and we all know how easy it is to do.

 

Another possible bit of anecdotal evidence for OEM tweaking might be that fact that the 06 was a limited run production car. I'm just guessing but perhaps that might mean SOA could tweak the model and not have to report emmissions data.

[deimos]

13.7, eh? That's pretty impressive. So you are saying that the fastest published times were posted by the 06 Spec.B despite its effectively higher gearing and increased mass.

 

I just wonder why there is such resistance on this site to the idea that the Spec.B is OEM tweaked. It is the simplest explantion after all and we all know how easy it is to do.

 

Another possible bit of anecdotal evidence for OEM tweaking might be that fact that the 06 was a limited run production car. I'm just guessing but perhaps that might mean SOA could tweak the model and not have to report emmissions data.

 

It could have also been a ringer as no other 06 spec b test came near the times listed in that test and Im sure subie wanted to fare well in an "awd sport sedan shootout"

[mccorry]

I really don't want to be drug into this RIDICULOUS argument... but I will ask this question...

 

VIMY.. when you take your car in for service.... ask for the part #'s for the ECU for a GT and a Spec B.

Are there different part #'s? I would bet a dime for a dollar that they aren't.

[Vimy101]

I really don't want to be drug into this RIDICULOUS argument... but I will ask this question...

 

VIMY.. when you take your car in for service.... ask for the part #'s for the ECU for a GT and a Spec B.

Are there different part #'s? I would bet a dime for a dollar that they aren't.

 

There wouldn't have to be a part # difference if the ECU base map is OEM altered.

[Vimy101]

It could have also been a ringer as no other 06 spec b test came near the times listed in that test and Im sure subie wanted to fare well in an "awd sport sedan shootout"

 

That could be the case but following your line of argument why then weren't LGTs tweaked for their tests? Why not all OEM offerings regardless of builder? Why not simply program a little more oomph into SOA flagship sedan line? After all, it is almost insanely easy to do.

[mccorry]

There wouldn't have to be a part # difference if the ECU base map is OEM altered.

 

Dude... a different MAP is a different ECU. Do you think that they flash them at the dealership?

Maybe the guy that installs them on the production line has an accessport in his pocket!

 

Hell.. SOA has different part No.s for Carpet hooks!

 

 

Wow... I hope that the next time I take my car in for any type of electrical service... they "accidentally" flash my ECU with the "top-secret Spec.B only" base map! Bwahahahahahaha!

[Vimy101]

Dude... a different MAP is a different ECU. Do you think that they flash them at the dealership?

Maybe the guy that installs them on the production line has an accessport in his pocket!

 

Hell.. SOA has different part No.s for Carpet hooks!

 

 

Bwahahahahahaha!

 

Correct me if I'm wrong but as I understand it an ECU is basically a computer that can be programmed. Quite an easy procedure I'm told.

[deimos]

That could be the case but following your line of argument why then weren't LGTs tweaked for their tests? Why not all OEM offerings regardless of builder? Why not simply program a little more oomph into SOA flagship sedan line? After all, it is almost insanely easy to do.

 

The oompf covers off on extra weight bigger wheels and gearing differences. Maybe the spec is a tenth or two faster, id hope so for the extra cash they charge.

 

And I would bet that many a manufacturer sends out ringers, possibly regular LGTs too.

 

Havent we beat this dead horse 1000 times in like 18 threads?

[mccorry]

^^^^

 

Answer - YES! We have!