Ok...so I took my 07 automatic tC to the track when it was stock, right out of the factory, and ran a 16.3 1/4 mile at 84. Now, after this list of mods my car is slower (16.6 at 82) and I am troubleshooting this problem as we speak. Any help or suggestions would be much appriciated, thanks.

Mods:Weapon-R short ram intake, House of billet throttle body spacer, Weapon-R intake manifold, DC Sport Header, Invidia Downpipe, Tsudo midpipe no cat with resinator, Greddy Evo 2 axel back with bigger muffler, house of billet crank pulley, radiator air diversion plate, back seats removed, passenger seat removed, spare tire and accesories removed, carbon fiber hood, 18" light weight wheels, kuhmo spt tires.

The car is not tuned and I do have software coming in the mail that will allow me to tune the car so there is no limits to troubleshooting.

Apparently you need to keep your foot on the throttle.

I keed. I keed.

9 times out of 10, it would be the driver, not the car. No matter how many mods you have, you're better off improving your driving first.

throw the throttle body spacer out it does jack for the tc and two it could possibly be from your rims. although they are light weight you did just up the rotation mass that the tc is used to (17 ") so that could play a part in it

Ditto on the TBS. Worthless.

What wheels are they anyway? Like, how much is "light weight" for an 18? The OEM 17s are about 21 lbs or 23 lbs. Could definitely go with some better tires as well.

Ur number 1 problem there is you have an automatic!

yes sell it get a 5spd

The TBS is pointless..also..isn't the intake manifold meant for boosted aplications? And don't you have to be tuned to run it properly?

The TBS is pointless..also..isn't the intake manifold meant for boosted aplications? And don't you have to be tuned to run it properly?
I think you can use the manifold for NA... but ya, you won't get crap out of it unless it's tuned. Not to mention the auto part.

Why people think it is worth taking an auto to a track is beyond me... I mean, I've seen very few people even autox an auto. Sometimes you can get away with it there more than some other types of racing... but damn.

9 times out of 10, it would be the driver, not the car.
Normally, yes... but since he has an automatic, all he has to do is press the 'go' pedal when the light turns green.

Unless they're OZ or something, I kinda doubt your 18" rims are lighter than the stock 17s. Your tires are garbage, too. These two things effectively cancel out the diet you put your car on. One thing that could be causing time discrepancies is fuel load, too. What's your tank looking like when you run?

Oh, and I'm bringing in my crusade against aftermarket pulleys. Take yours off if you like your block.

like most people here said 1 st issue and auto....cant do much with them..not meant too be...you did all that work to improve your performance even though you know its and auto...ive read many threads on here people mods auto which is fine but you wont see a big difference as you would a 5 speed...i say trade it in get a 5 speed if you know how to drive one...more control on the car and escpically your speed

1. Stock wheels are 19lbs
2. The fact he has an auto is irrelevant


what are your 60ft times?

also try cleaning your MAF and check to make sure your spark plugs aren't fouled. I just had this same issue and spent all of Saturday trying to figure out why i couldn't break 11 sec in the 1/8. Turned out one of my front calipers was not operating properly and was getting stuck from where the brake pistons were dirty and my ceramic pads were dragging :doh:

you should be in the mid 15s or so. maybe even slighty lower

Intake manifold and throttle body spacer will not do much unless you get your car tune and even after that the TBS might not do anything at all, it might evem hurt you, they are meant for boosted applications.

What were your 60' times

Also take off TBS
Make sure your rims are actually light weight
Good tires
Take off intake mani
Send back whatever you just bought to tune your car
Put your passenger seat back in
Try it again, Its probably just your 60' that sucked.

remember, even if your rims are "lighter weight" you put on bigger tires that probably weight more than the stock tires, so it wasn't a big deal.

Ok so I know the 18" rims may slow me down a little thats why I posted it to show everyone all the facts but they shouldnt slow me down that much. They are motegi ff7's, is that lighter, im not sure?

Why are kuhmo spt a bad tire and what do you suggest?

Dont make me laugh when you say bad driver, it's an auto you brake launch and hold the throttle to the floor, not rocket science.

Stock 60 FT:2.4933
New 60 FT:2.5111

Steventc07: I recently cleaned and oiled the intake, when you say clean the MAF do you mean the actual sensor or did you just mean the intake? Also, how did you come to the conclusion that your caliper was getting stuck and whats the best way to check the spark plugs?

I have read that the throttle body spacer and the crank pulley are both bad ideas. But, with the tune will that help the throttle body? Also, I put my car up on a couple stands yesterday, took off the passenger tire to get to the crank. I was going to take off the crank and put the stock back on but I couldnt find any place to rent an impact wrench on sunday.
:nope:
I am going to find one though and test my car in a 0-85 mph run with and without an aftermarket crank pulley to see the difference if any. But, the results may no be accurate for all tC's seeing that something is wrong with mine.

On the stock run my car was at a 1/4 of a tank maybe a little lower on 93 octane. On the new run I did a couple runs on 93 octane at 1/8 of a tank then mixed race gas with that to a 1/4 of a tank. Never broke 16.6 either way.

Reguardless if the car is automatic or standard there should still be an increase in performance. I am trying to figure out what is hindering this performance not that this performance could be better if the car was standard.

What is TBS?

Sorry I feel dumb TBS = Throttle Body Spacer

lol, why did you put race gas in an automatic tC?

I put race gas in for fun.

Update, Not sure if this is of importance or not but I went to Auto Zone and got an OBD II scan and came up with these results.

1) Catalyst system efficience below threshold (well this is obviously because I have no cat).
2) Evaporative emission control system incorrect purge flow
3) Evaporative emission control system pressure leak detected - large leak

I know what is wrong in #1 but can someone enlighten me with #'s 2 & 3, and would it have any effect on acceleration?

#2 and #3 are from having a loose gas cap, most likely.

Hehe race gas in an NA auto that recommends 87. It's useless to run any higher octane than 87 until you are boosted or nitrous.

Track temperature can affect performance as well as the power your engine can produce. Just weigh the old tires and rims and the new tires and rims and see which are lighter and also check the circumference - smaller is better for drag racing. Definately lower the octane back to regular or plus at most. Also if possible figure out the weight of the vehicle or the weight of all the stock stuff you swapped out for the "high performance" stuff you added to see if you increased the car weight.
At some point the ECU will be adjusting the A/F mixture with the cat missing and that can affect the power levels of the engine too. Maybe a ECU reset is in order.

If it is not a loose gas cap could it be a more serious problem?

I have to go to class now but after I will check into the ecu reset and also check for any new suggestions. Any help is much appriciated!

Steventc07: I recently cleaned and oiled the intake, when you say clean the MAF do you mean the actual sensor or did you just mean the intake? Also, how did you come to the conclusion that your caliper was getting stuck and whats the best way to check the spark plugs?

Reguardless if the car is automatic or standard there should still be an increase in performance. I am trying to figure out what is hindering this performance not that this performance could be better if the car was standard.

The MAF (sensor) can get dirty and lead to improper readings thus throwing off your Air to Fuel ratio. Go to Napa, get some Mass Air FLow Sensor cleaner.

Again take the throttle body spacer off. it is not needed.

Nor is the race gas. Higher octane fuel is only needed if you are advancing the timing and/or increasing compression via different pistons, porting, boost, Nitrous, etc to prevent detonation/knocking. 87 burns faster than 93 and is entirely appropriate for your car.

How do you check the spark plugs? You take them out and look at them....
http://www.theultralightplace.com/sparkplugs.htm

I also checked my compression as I may have popped the head gasket from where I had the turbo on my car (don't right now), but this is prolly not necessary for you.

Your O2 sensor could be fouled as well.

How did I figure out it was the brakes? I went through every system that I thought could be causing the issue as well as I could.

The car should at least run what is stock. Were these passes made at the same track? What was the temperature and humidity each day? These two things can vastly affect your time.

W/O any diagnostic gauges i.e. wideband, intake temp gauge, etc it is much harder to determine the problem. not telling you to buy any, just saying

Ur number 1 problem there is you have an automatic!

Worrd!

Hey! I run race gas in my auto!!! lol :) I ran 108 (I think thats what it was - whatever the highest unleaded sunoco has) and i pulled 0 (full factory advance) timing on 8 psi and i ran .2 faster and 2 mph higher on the top end :D:D:D Gah I wanna go to e85 so i can run more timing daily :). But back on topic - dont run race gas in your n/a car it will actually make it worse- i promise - higher octane = harder to burn = better when you want to avoid pre-ignition in a boosted car with further timing advance = worse when you are running n/a with a car that already has a really safe timing curve and dont have to worry about pre-ign. Go back to 87 i promise the car will actually run better - as for your other mods - dont know what to tell you except ditch the tbs - also did you weigh your car before and after? Most tracks have a scale at the end of the track... Mines sitting around 3350 lol - thats with my fat ___ in it and full sound system :) As for the crank pulley its a heated discussion technically you should see a small gain from it - many say it improves throttle response - but on the flip side theres a possibility of it doing long term damage to the motor. I wont pick one way or the other - ive never personally seen said damage so i cant testify one way or another. Also an important factor most are leaving out, what was the temp on the first run and the second? Itll make a big diff - also I hate to say it, but its something with your setup, highly doubt its driver error - i dont see driver error in an auto being able to caus e a 2mph diff in trap speed unless you let off or something :P

Saw a bone stock auto run 16.2 four consecutive times one night... girl driving too :)

Yeah my auto ran a 16.4 consistently with catback exhaust when i first got it - reminder this is at the worst track ever - in the heat of an Oklahoma summer :P so it was always 90+ on the track when I ran it n/a. Also I dont believe a catback exhaust really does much of anything performance wise so I doubt it made any real diff other than the sound :P

Get new plugs, tune it for 87, and run 87. After that you should be fine. My auto tC ran 15.8 w/ intake, exhaust, and crank pulley...

9 times out of 10, it would be the driver, not the car. No matter how many mods you have, you're better off improving your driving first.
+1 and i am living proof of that....

I remember when i got my tc back in 05 i went to the track and hit a 16.0 flat bone stock(im 5sp)

then I modded the tc (still in 05) with dc header, weapon r cai (i just added a extension to the short ram), injen axle back, and crank pulley....Then i hit a 15.4 and i was so impressed with myself


....well years later and a lot less mods I hit a 15.2 with just a tsudo catback and ebay intake....

so leason is that the driver makes the car go and not the mods....

I seriously doubt there is that much too learn with an automatic.

Get new plugs, tune it for 87, and run 87. After that you should be fine. My auto tC ran 15.8 w/ intake, exhaust, and crank pulley...

Do you have a timeslip for this? Just curious, unless you have some factory-freak tC I'm going to raise the B.S. on this one.

To the original OP:

Your 60 ft. times need to improve. My best is 2.399.

ppl how many times do i have to say, tracks are different......stop telling him he sucks at driving. He ran a pretty consistent 60ft but experienced a lower trap speed and higher time. With an auto all he really can help is the 60ft, the rest is the car

ppl how many times do i have to say, tracks are different......stop telling him he sucks at driving. He ran a pretty consistent 60ft but experienced a lower trap speed and higher time. With an auto all he really can help is the 60ft, the rest is the car

yup yup