Notices
C5 General General C5 Corvette and C5 Z06 Discussion not covered in Tech
Sponsored by:
Sponsored by:

Why is my C5 slow?

Old 12-09-2006, 02:14 AM
  #1  
jah
Intermediate
Thread Starter
 
jah's Avatar
 
Member Since: Nov 2006
Posts: 28
Likes: 0
Received 0 Likes on 0 Posts
Default Why is my C5 slow?

At the track today, I did the 1/4 mile in 15.1 sec. with the car loaded with full tank of gas (I weigh 230lbs). It's all stock '98 coupe with 49,000 miles. What are some areas I can look into? Change the air filter? Check/change the spark plugs? What else?

Thanks all.
Old 12-09-2006, 02:23 AM
  #2  
01yellowc5
Drifting
 
01yellowc5's Avatar
 
Member Since: Dec 2004
Location: Woodlake,The hill is without the king, California
Posts: 1,455
Likes: 0
Received 1 Like on 1 Post
St. Jude Donor '08
Default

what was your 60'
Old 12-09-2006, 02:29 AM
  #3  
urwtdrm
Pro
 
urwtdrm's Avatar
 
Member Since: Feb 2003
Location: Sacramento CA
Posts: 747
Received 0 Likes on 0 Posts

Default

I would guess a fuel problem
Old 12-09-2006, 02:29 AM
  #4  
Mpwr
Drifting
 
Mpwr's Avatar
 
Member Since: Jul 2005
Location: Franklin Square Long Island NY
Posts: 1,694
Likes: 0
Received 3 Likes on 2 Posts

Default

Somethings terribly wrong.. what were your #'s...please post all of them
Old 12-09-2006, 02:32 AM
  #5  
jah
Intermediate
Thread Starter
 
jah's Avatar
 
Member Since: Nov 2006
Posts: 28
Likes: 0
Received 0 Likes on 0 Posts
Default

15.1,15.2,15.4,15.1

not sure about 60 times, but that part seems OK, my top end is where I lost - top speed always 91mph.

How can I check the right fuel delivery?

What other things can I check?
Old 12-09-2006, 02:45 AM
  #6  
BaneZ06
Supremacy 1 car at a time
Support Corvetteforum!
 
BaneZ06's Avatar
 
Member Since: Jul 2006
Location: West Chester Pa
Posts: 1,682
Likes: 0
Received 0 Likes on 0 Posts

Default

Holy crap! did the car always feel this slow? When did it feel like it lost power.
Old 12-09-2006, 02:49 AM
  #7  
VetteHunting
Safety Car
 
VetteHunting's Avatar
 
Member Since: Apr 2004
Location: We cant stop here... this is bat country
Posts: 4,813
Likes: 0
Received 2 Likes on 2 Posts
Default

Need 60 foot times.
Old 12-09-2006, 02:53 AM
  #8  
jah
Intermediate
Thread Starter
 
jah's Avatar
 
Member Since: Nov 2006
Posts: 28
Likes: 0
Received 0 Likes on 0 Posts
Default

I just got it. What should the 1/4 times be like? low to mid 13's? Top speed - should be in the 100's right? What can I check to help me locate the problem(s)?
Old 12-09-2006, 02:56 AM
  #9  
Cobra4B
Team Owner
 
Cobra4B's Avatar
 
Member Since: Mar 2001
Location: Virginia Beach
Posts: 25,889
Likes: 0
Received 5 Likes on 5 Posts
CI 3-5-6-7-8 Veteran

Default

A bone stock MN6 w/ the 345 hp LS1 should run low 13's @ 106ish mph. For reference I piloted my mom's bone stock '99 MN6 to a 13.1 @ 107.
Old 12-09-2006, 03:09 AM
  #10  
Jersey_C5
Racer
 
Jersey_C5's Avatar
 
Member Since: Jul 2006
Location: Eastampton New Jersey
Posts: 410
Likes: 0
Received 0 Likes on 0 Posts

Default

What is your 60 ft? Stick or auto trans? Where do you live? My bone stock auto 2004 went 12.92 @ 107
Old 12-09-2006, 03:34 AM
  #11  
jah
Intermediate
Thread Starter
 
jah's Avatar
 
Member Since: Nov 2006
Posts: 28
Likes: 0
Received 0 Likes on 0 Posts
Default

Thanks guys, I can see that somethings wrong. I live in El Paso, TX and was told that this stock Auto Vette belonged to some doctor before he traded it in w/49,000 mi.

What steps do I take to check out problem areas. I think it might be the fuel or air delivery - change filters? Sorry, I didn't get 60' times, but I seemed to do well there. The other cars would pass me after we got half way down the 1/4 mile course.

Thanks
Old 12-09-2006, 03:48 AM
  #12  
JTE
Melting Slicks
 
JTE's Avatar
 
Member Since: Feb 2002
Location: Coal Valley IL
Posts: 3,179
Received 13 Likes on 6 Posts
CI 4-7, 9 & 10 Veteran

Default

We still need to know what your 60" times were. Also, did you run the car in 3rd gear since it is an automatic? If you ran it in 4th, that is part of the problem. You also likely have the 2.73 rear end and not the optional 3.15 available for automatics.

If your 60' times are too high, this will also explain some of the low mph.

Do you have heavy aftermarket wheels on the car? Is there added weight such as subwoofer box? Full tank of gas also doesn't help.

The DA or outside temperature also is a factor. Elevation is also a factor but not likely in Texas.
Old 12-09-2006, 04:05 AM
  #13  
jah
Intermediate
Thread Starter
 
jah's Avatar
 
Member Since: Nov 2006
Posts: 28
Likes: 0
Received 0 Likes on 0 Posts
Default

wheel are stock. Temp out side was around 50F.

I used overdrive. Should I use 3rd all the way down?

I had the traction control on. Should I turn it off?

Also, how can I check the transmittion oil? I think I saw leaks on the driveway before I left to the drag races? This alone might be the cause - no?

Last edited by jah; 12-09-2006 at 04:10 AM.
Old 12-09-2006, 04:11 AM
  #14  
omarcoolguy
Burning Brakes
 
omarcoolguy's Avatar
 
Member Since: Oct 2006
Location: HANOVER PARK IL
Posts: 1,140
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by jah
wheel are stock. Temp out side was around 50F.

I used overdrive. Should I use 3rd all the way down?

I had the traction control on. Should I turn it off?

put the competitive driving mode on.....hold the T/C button down for 8 sec....while ur stopped.....and i leave it in drive....??.......it seems the be the fastest when i do that....ive never ran down a real track b4....go to a private closed road and practice....u will be able to feel the car urself...u dont need a clock telling u good luck
Old 12-09-2006, 04:18 AM
  #15  
JTE
Melting Slicks
 
JTE's Avatar
 
Member Since: Feb 2002
Location: Coal Valley IL
Posts: 3,179
Received 13 Likes on 6 Posts
CI 4-7, 9 & 10 Veteran

Default

Yes, use drive all the way down the 1/4. Turn the traction control off.

The tranny fluid level is not simple to check. It is easier on a lift since the tranny is in the rear of the car.
Old 12-09-2006, 04:41 AM
  #16  
jah
Intermediate
Thread Starter
 
jah's Avatar
 
Member Since: Nov 2006
Posts: 28
Likes: 0
Received 0 Likes on 0 Posts
Default

I will turn the traction control off next time (I can't believe I didn't think of that there!). Could this make that big of a difference?

What else can I check? Fuel/Air filters? Should I have a shop check it out? Will a diagnostic test tell me anything or do they have to do a dyno on it? About how much is that (incl. vette tax!)?
Old 12-09-2006, 05:39 AM
  #17  
Herringchoker
Burning Brakes
Support Corvetteforum!
 
Herringchoker's Avatar
 
Member Since: Nov 2005
Location: "Man been singin' the Blues, since he began to till the ground"...Vancouver, USA WA.
Posts: 1,053
Likes: 0
Received 2 Likes on 1 Post
Default

Fuel filter! S/B replaced at 30K.

Get notified of new replies

To Why is my C5 slow?

Old 12-09-2006, 06:00 AM
  #18  
Jersey_C5
Racer
 
Jersey_C5's Avatar
 
Member Since: Jul 2006
Location: Eastampton New Jersey
Posts: 410
Likes: 0
Received 0 Likes on 0 Posts

Default

There has to be something wrong. I've left the traction control on while bracket racing and I still cut 2.1xx 60s in 85 degree heat and went 13.6 letting off. I also have 2.73 gears and was still stock when I went 12.92 @ 107. There might be something going on there with your car.
Old 12-09-2006, 06:05 AM
  #19  
frckid
Advanced
 
frckid's Avatar
 
Member Since: Oct 2005
Location: California City CA
Posts: 76
Likes: 0
Received 0 Likes on 0 Posts
Default

Make sure you're pushing the pedal all the way down
Old 12-09-2006, 07:43 AM
  #20  
Gannet
Safety Car
Support Corvetteforum!
 
Gannet's Avatar
 
Member Since: Mar 2006
Location: Sarasota Florida
Posts: 4,448
Received 4 Likes on 4 Posts
St. Jude Donor '06

Default

It doesn't matter what his 60' times are, what gear he was in, what driving mode he was in, etc. If he's only trapping 91 mph he's WAY down on power. Like something on the order of 100 rwhp down. The car needs attention from a good Corvette mechanic. If it otherwise runs well (not rough or smoking) it has to be something relatively simple. That or somebody swapped in a L-48 while he wasn't looking!

I bet this guy is going to get the cheapest 100 rwhp boost on record.

Last edited by Gannet; 12-09-2006 at 07:51 AM.

Thread Tools
Search this Thread
Quick Reply: Why is my C5 slow?



All times are GMT -4. The time now is 05:07 AM.