Performance increase
Thread Starter
Advanced
Joined: Jun 2009
Posts: 97
Likes: 0
From: Gallatin Tennessee
Performance increase
Here's some performance upgrades I've done and some numbers from a Dyno.
I installed the Vararam intake with the Power Duct. I had my car set up on a Dyno and tuned. Along with these changes I also had the 2.73 diff swapped out for a 3.73 diff (DTE).
Let me say, before I give you my numbers... these changes have really livened up my car. It's a thrill to drive now. I was pretty disappointed with the performance when I first got it.
Rear wheel HP = 305.32
Rear wheel TQ = 304.97
How does this sound for the changes I've done so far?
I'm still not real happy with the holeshot. It'll spin the tires now as before it wouldn't even chirp the tires. But it's still a little sluggish coming out of the hole. I know this car is way more powerful than the 85 Vette I had, but that 85 would light the tires up when I smashed the gas. I mean they would fry! No power braking needed. It was a riot to drive.
Let me know what you think.
I installed the Vararam intake with the Power Duct. I had my car set up on a Dyno and tuned. Along with these changes I also had the 2.73 diff swapped out for a 3.73 diff (DTE).
Let me say, before I give you my numbers... these changes have really livened up my car. It's a thrill to drive now. I was pretty disappointed with the performance when I first got it.
Rear wheel HP = 305.32
Rear wheel TQ = 304.97
How does this sound for the changes I've done so far?
I'm still not real happy with the holeshot. It'll spin the tires now as before it wouldn't even chirp the tires. But it's still a little sluggish coming out of the hole. I know this car is way more powerful than the 85 Vette I had, but that 85 would light the tires up when I smashed the gas. I mean they would fry! No power braking needed. It was a riot to drive.
Let me know what you think.
Le Mans Master
Joined: Dec 2001
Posts: 5,707
Likes: 555
From: St. Peters MO
C7 of Year Finalist (stock) 2019
2018 C7 of Year Finalist
Here's some performance upgrades I've done and some numbers from a Dyno.
I installed the Vararam intake with the Power Duct. I had my car set up on a Dyno and tuned. Along with these changes I also had the 2.73 diff swapped out for a 3.73 diff (DTE).
Let me say, before I give you my numbers... these changes have really livened up my car. It's a thrill to drive now. I was pretty disappointed with the performance when I first got it.
Rear wheel HP = 305.32
Rear wheel TQ = 304.97
How does this sound for the changes I've done so far?
I'm still not real happy with the holeshot. It'll spin the tires now as before it wouldn't even chirp the tires. But it's still a little sluggish coming out of the hole. I know this car is way more powerful than the 85 Vette I had, but that 85 would light the tires up when I smashed the gas. I mean they would fry! No power braking needed. It was a riot to drive.
Let me know what you think.
I installed the Vararam intake with the Power Duct. I had my car set up on a Dyno and tuned. Along with these changes I also had the 2.73 diff swapped out for a 3.73 diff (DTE).
Let me say, before I give you my numbers... these changes have really livened up my car. It's a thrill to drive now. I was pretty disappointed with the performance when I first got it.
Rear wheel HP = 305.32
Rear wheel TQ = 304.97
How does this sound for the changes I've done so far?
I'm still not real happy with the holeshot. It'll spin the tires now as before it wouldn't even chirp the tires. But it's still a little sluggish coming out of the hole. I know this car is way more powerful than the 85 Vette I had, but that 85 would light the tires up when I smashed the gas. I mean they would fry! No power braking needed. It was a riot to drive.
Let me know what you think.
As for breaking the tires loose from a dead start. Have you tried it with the traction control off? I would suggest Competitive Mode as this will disable Traction Control but leave Active Handling on. If you have a 99 Active Handling was an option that year so you may not have it and therefore wouldn't have Competitive Mode.
Melting Slicks
Joined: May 1999
Posts: 2,365
Likes: 0
From: Vancouver BC
You should easily be able to spin the tires without traction control, even without any mods...the gears will make the most difference in acceleration in your case...intake and tune make more hp, but you won't feel a huge difference...but going to 3.73 will be a whole new driving experience. 
Advanced
Joined: Sep 2009
Posts: 50
Likes: 0
2.73 to a 3.73 and the off the line power still disappoints? Sounds like you need to get a new stall converter. I would recommend either a Yank or Precision Industries. With those 3.73s and a 2800-3000 rpm stall converter you'd likely shave .5 seconds off your 1/4 time. Not sure if you drag race, but that kind of give you an idea of what a difference those mods make on an auto.
Drifting
Joined: Oct 2002
Posts: 1,774
Likes: 66
From: SoCal
That's what I did. Now I can't seem to get any traction. 
Another reason why you might not be able to fry the tires is Torque Management on your C5 auto trans. Disable that and then you should be able too. With a 3.73 diff, I would think you should be able to with traction control turned off. If not, take to a shop and have a tune done and have them turn off the Torque Management as well.
Then you should be able to make the tire companies happy.
Another reason why you might not be able to fry the tires is Torque Management on your C5 auto trans. Disable that and then you should be able too. With a 3.73 diff, I would think you should be able to with traction control turned off. If not, take to a shop and have a tune done and have them turn off the Torque Management as well.
Then you should be able to make the tire companies happy.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
5 Best & 5 Worst Corvette Daily Drivers
Joe Kucinski
The Headlights of Every Corvette Generation Explained
Joe Kucinski
5 Best & 5 Most Overrated Corvette Track Packages of All Time!
Joe Kucinski
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
Thread Starter
Advanced
Joined: Jun 2009
Posts: 97
Likes: 0
From: Gallatin Tennessee
I don't drive with the traction control on. That's one of the first things I do is take that off ( a single button on the console). The torque management control is off. DTE turned that off when they installed the 3.73 gears, and Vettesport comfirmed the torque management was off when he performed the tune on the dyno. I thought about a new stall converter, but I've been told by enough people that I should be able to fry the tires now, I thought I should find out why I'm not, before I add more parts.
Burning Brakes
Joined: Aug 2009
Posts: 945
Likes: 8
From: Olympia WA
I don't drive with the traction control on. That's one of the first things I do is take that off ( a single button on the console). The torque management control is off. DTE turned that off when they installed the 3.73 gears, and Vettesport comfirmed the torque management was off when he performed the tune on the dyno. I thought about a new stall converter, but I've been told by enough people that I should be able to fry the tires now, I thought I should find out why I'm not, before I add more parts.
Administrator
Joined: Mar 2001
Posts: 368,636
Likes: 24,868
From: In a parallel universe. Currently own 2014 Stingray Coupe.
C7 of the Year - Modified Finalist 2021
MO Events Coordinator
St. Jude Co-Organizer
St. Jude Donor '03 thru '26
NCM Sinkhole Donor
CI 5, 8 & 11 Veteran
Not bad numbers now, but what were the original hp and torque numbers? With the new rear gears, you should feel a heck of a difference in take off.
Banned Scam/Spammer
Joined: Jul 2006
Posts: 2,911
Likes: 10
From: Simi Valley CA
The difference you feel is from the rear end change, not the intake. You should either put headers/cam on it, or just go FI. 
FI goes from "excitement" to "down-right scary" real quick.
FI goes from "excitement" to "down-right scary" real quick.
Race Director
Joined: Aug 2003
Posts: 16,270
Likes: 30
From: "It's 106 miles to Chicago, we've got a full tank of gas, half a pack of cigarettes, it's dark, and
St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16-'17-‘18-'19
NCM Sinkhole Donor
I am a believer in the following:
1. Better breathing (intake improvement) requires better exhaust. If you can take more air in - you need to be able to get more air out. That means long tube headers, high flow cats and a cat-back exhaust.
2. Improved intake and exhaust requires a tune from a professional tuner to take advantage of the improvements.
With intake, headers, cats and a tune - you should expect something in the area of 35 rwhp gain, that plus your gear swap, you should be able to absolutely melt the tires.
Personally - I like the Kooks system with their high flow catted x-pipe.
1. Better breathing (intake improvement) requires better exhaust. If you can take more air in - you need to be able to get more air out. That means long tube headers, high flow cats and a cat-back exhaust.
2. Improved intake and exhaust requires a tune from a professional tuner to take advantage of the improvements.
With intake, headers, cats and a tune - you should expect something in the area of 35 rwhp gain, that plus your gear swap, you should be able to absolutely melt the tires.
Personally - I like the Kooks system with their high flow catted x-pipe.
Instructor
Joined: Aug 2008
Posts: 137
Likes: 0
From: Wallingford Ct
Performance
I have the same mods as you but a couple in addition. Chuck C.O.W. talked me into a 2600 stall and later on he put a set of AR long tubes. You can lite the tires at will. I really like his work! Car really performs well. Its so much fun but Its hard to keep your foot out of it! Give him a call. I'm sure he'll get you pointed in the right direction.
Thread Starter
Advanced
Joined: Jun 2009
Posts: 97
Likes: 0
From: Gallatin Tennessee
The tires are Michelin ZP Pilot Sport A/S zero pressure 245/45 zr17 95y.
They were on it when I bought. And they're pretty new.
I just went outside and warmed up my car. In my driveway... I left TC on and nailed it. It started out not really frying the tires but spinning just enough to leave marks on the pavement and it felt a little doggy. A second or two. As the RPM's built it started to cut loose more.
Now... with TC off. Almost the same thing. At initial takeoff the tires were barely spinning. Just enough to leave marks and it felt doggy. Just like with TC on. The difference though, once the RPM's built the tires really cut loose and I left a cloud of tire smoke. But, I'll guess that
started to happen about 15 or 18 feet down the driveway.
It's hard to describe but that's the best I can do. What do you think?
They were on it when I bought. And they're pretty new.
I just went outside and warmed up my car. In my driveway... I left TC on and nailed it. It started out not really frying the tires but spinning just enough to leave marks on the pavement and it felt a little doggy. A second or two. As the RPM's built it started to cut loose more.
Now... with TC off. Almost the same thing. At initial takeoff the tires were barely spinning. Just enough to leave marks and it felt doggy. Just like with TC on. The difference though, once the RPM's built the tires really cut loose and I left a cloud of tire smoke. But, I'll guess that
started to happen about 15 or 18 feet down the driveway.
It's hard to describe but that's the best I can do. What do you think?
