Upon borrowing a friend's G-Tech last night, I did a few 0-60 and 1/4 mile runs in my TSX last night. I know my 5AT is not a fast car by any means, but I ended up getting times like 0-60 in 9.6 seconds and 17.1 1/4mi times. Keep in mind too that I am not stock(i/h/e). How do I make this thing get better readings, because I know my car isn't a 17 second car. Could the passenger in the car have made that big of a difference?

 

what are the conditions of your run? Did you do it in SS, or full auto? Full tank? What are your rims? I don't know much about Gtech, but does it have to be calibrated in some way?

By my own non-scientific runs, I consistently get a little under 8 seconds with I/H, and thats not trying hard by any means.

 

When it comes to acceleration:

Corvette Z06 > Lexus IS350 > BMW330i > Accord V6 > Acura TSX

Accept life, move on.

 

It was a little windy outside and was ~72 degrees. I'm not exactly sure what way the wind was blowing. I ran it in SS with VSA off. My tank is almost full. I have 18" OZ Ultraleggeras(which are supposed to be lighter than the stock wheels).

There is no calibration to really do, except calibrate the RPMs.(which I did)

 

I know that. But last time I checked, even the 5AT TSX was not a 17 second car. Especially a bolt-on one.

 

Take it to a track and see how close it is before you start tweaking it. I found mine was pretty accurate with only the basic specs of my car plugged in (weight, rollout, etc.). You should be going for accuracy, not just better numbers.

 

No track around me for at least 200 miles

 

I had someone on the way home the other day box me in and then walk away from me...the guy was/is a complete ass. I wasnt overly trying to get around him, but I couldnt have even if I had tried as it was a 350Z track edition. This clown actually lives a street over, which I did not know until I saw him on Sunday rolling down our street. I asked if he wanted to try that shat again with my TSX's mean older brother, which I was washing at the time. He declined.

 

Did you calibrate the driver?

 

^^ and here I was blaming the TSX.

 

Nah man....I forgot to mention that I missed 3rd gear, granny shifted the whole way, and had massive wheelhop. [/sarcasm]

Not exactly rocket science to drive "sport shift" in the 5AT.

 

Even though your wheels are lighter than the stock ones, their larger circumference places a majority of the rotating mass farther away from the hub than the stock wheels. The resultant flywheel effect decreases acceleration as the wheels take more energy to get up to speed, because the bulk of their mass has a higher linear velocity at a given RPM than a smaller wheel with the mass closer to the hub.

Plus-sized wheels really don't offer that many performance advantages aside from the fact that they sometimes can increase the handling potential by increasing tire width, while decreasing sidewall thickness and flex during cornering. Mostly they're just for looks.

Look at a race car sometime. They run the smallest wheels that will fit over the brakes. Especially on drag cars, where straight-line acceleration is paramount.

 

Did your G-Tech stop counting when you got to 60mph? Sometimes mine has had trouble with automatic transmission cars. The launch screws it up somehow and it can't properly figure the rate of acceleration and when the car actually hits 60mph.

How did you launch the car? I don't know what the stall speed is on the stock torque converter, but I'd imagine it's no more than 2500 RPM.

 

How do you know he has changed the rolling diametre by changing to 18"?

You are assuming he has changed to a larger rolling diametre which is not necesarily the case. Almost everyone who upsizes rims also changes to a lower profile tyre.

 

I'm not talking about tire OD, I'm talking about wheel OD only.

 

18" wheels and a passenger can definitely hurt your times.

Not sure on how exactly to launch an AT TSX, but did you try raising the RPMs prior to launch?

 

I know. What I am suggesting is that if the overall circumference is the same what you are stating regarding acceleration is incorrect.

If you have a 17" tyre and rim package weighing 18kg with the same rolling diametre as an 18" tyre and rim package weighing 15kg -- according to your logic the 17" package will accelerate faster?

 

Yeah I brake torqued it as much as it would go(~2200 rpms if I recall correctly) and VSA was off. I'm hoping at least some of it is because of my passenger(who wasn't a small guy). The TSX tends to respond to weight badly. Other than that, I don't know. I think I am gonna borrow it again some time and try it without him in the car.

I was also reading on the website about the conditions affecting the timer. I don't know how flat the road was that I was on. Thanks for all the input you all

 

What I do is hold the brakes while applying enough throttle to reach the torque converter's stall speed, or slightly above. This way when I release the brakes the transmission is transferring power, while multiplying engine torque at whatever the maximum stall ratio is. As long as there isn't any wheelspin, the car will accelerate as fast as the driveline can get it to, from the moment the brakes are released. Basically, this removes the element of lag between when you press the pedal to when the driveline spins up to speed and pressurizes the torque converter.

Yes, that is what I'm saying. It sounds weird, but when you think about it, it makes sense. A greater proportion of the mass of the larger rim is farther away from the hub than on the smaller one. So, at a given RPM, it will be moving at a higher linear velocity than it would with the smaller rim. In order to accelerate the larger wheel to the same RPM as the smaller one, and thus the same vehicle speed, a majority of the wheel's mass needs to be accelerated to that higher linear velocity. All of this takes energy; energy that should be instead contributing to accelerating the vehicle. It's all dependent on how the wheel's mass is distributed around the rim.

Now, if the 18" wheel/tire is lighter than the stock 17" wheel by a huge margin, this all becomes a moot issue because its much lighter weight compensates for its inferior mass distribution. I'm not sure how many wheels out there are all that much lighter than the stock ones, though. The stock 17x7s are 23lb. My set of SSR Competitions are lightweight forged 18x8s, and weigh 16lb. each. Once you add tires, the differences can become negligible depending on which tire you choose (mine are within a few lb. of stock with tires). In any case, the 18" tire's sidewall will be thicker and stronger than the 17", and thus weigh more as well. All of this extra mass is at the outermost diameter.

So obviously there is no hard and fast rule to support this, but generally speaking it does hold true quite often. Thus my original example of how virtually every race car uses wheels that are as small and as light as possible.

 

Now you tell us. How much does your passenger weigh?

 

Like I said before, the driver needs calibration = user error

 

^^

 

lol..good statement~

 

Sounds correct to me...

As for the passenger, I think the general weight rule is for every 100lbs = ~.1 second in the 1/4 mile. Of course, this varies per car, motor, etc...

 

do you mean a TL?

 

I'm not sure your mods are helping you either. The Injen CAI is proven to rob the TSX of low end torque, and its worse on an AT. You're losing precious launching ability. The header isn't helping any without a high flow cat and/or hondata, and there isn't any gain from such a big exhaust as the GReddy. Again, with the AT, you're probably losing low end torque with that exhaust. The bigger wheels aren't helping either.

Whatever top end gains your mods are giving you, I believe they are equally robbing you (or more) in the lower and middle revs, which is what counts here to get you started.

 

7g accord groups once had a member who ran his nitrous k24a4 accord at the dragstrip with a 160 lb passenger and he mentioned regardless of NA or N2O, the passenger was worth about half a second vs empty.

also find out if your location is altitude and use an nhra correction table to find equivalent sea level time.

 

no, a vette...I dont think the TL could get the job done. (thats why I was agreeing with jlukja )

 

With 2 wheel-tyre packages with the same rolling diameter but one with 17" and the other 18" rims, the one with more weight centered on the outside (18") ring diameter will have higher inertia.
So the 18" package will have higher inertia that has to be overcome in order to increase the wheel RPM.

 

^^ I retract that statement. I just read your original post and you did mention a passenger.

I think it was a combination of factors including having an almost full tank, a passenger, and the 18" rims.

 

In addition to calibrating the RPM, you have to enter vehicle weight so I'm assuming you did that and it's correct (including your weight and your passenger's). You also have to make sure the G-Tech is mounted solidly, you can't let it move around at all during acceleration or it'll throw the accelerometers off.

Plus, doing a good acceleration run takes a fair amount of practice. The first few runs I made (with a mod'ed 6mt) came up 7.8 sec, 8.2 sec, stuff like that. I learned how to launch, etc., from trial-and-error, and my best run so far is 6.5 sec. A one-second difference is not a lot in terms of stuff you can not do exactly right accelerating a car.

Get rid of your passenger, make sure your Gtech is properly calibrated and absolutely securely mounted, make sure it reads "0g" when you're parked on level ground, and make several runs on what you know is a level (and empty) street with a minimum of wind. I'll bet your times drop.

 

Thanks for all the help everyone. I'm gonna try some more runs when my friend gets back from vacation.

 

Bring a spirit level so that you can make sure that the road is truly level.

 

the nsx?

 

No no no. Do it by yourself. You'll get better times without a passenger.

 

Oh yeah I know. But it's his G-tech so I gotta borrow it from him when he gets back.

 

I just got a new G-Tech RR.
I did 4 runs today. The outside temp was 30 degrees the road was flat (and i ran it in both directions).There was no wind. My 2006 TSX 5AT has Hondata as it's only performance mod. Here are the results. (Note these times incude rollout.

 

sadly my 5at didnt die by the 330... i lost by maybe 1 1/2 cars with my 06 with an intake... and he was an at with 18s and a dnon chip (which in my opinion he wasted his money on it)

 

You're going to need to hit the top end of 3rd gear to get peak numbers out of the car, no? It looks like you're posting the data from your reving of 1st gear, from 2.5k roll on.

Nevertheless, I love how linear HP / flat TQ is after hondata. Those lines look great.