calbrit561

So I had an 03 vert with a 6sp and now I have a 99 vert 6sp. My 99 just feels like a dog compared to my 03.even with a blackwing and street tune my car felt slower than my old 03. I recently have just installed headers and a bb prt cat back and now my car feels just a tad bit faster than my 03.


I am also not the only one who feels this way as my father and brother both agree with me. I have yet to get the car retuned since the header install but I plan on trying to find a ls6 intake manifold for a reasonable price before I get a mail order time from ECS. Any thoughts as to why I feel this way

calbrit561

Also before anyone mentions it I have done a full tune up. Also I forgot to mention my 99 had run flats currently done they came on the car my old car had real performance tires just can't remember which ones I had.

Pounder

If you have the TC on and the tires lose traction the TC will apply the brakes to the tire which is slipping and will retard the timing !!!!!!

calbrit561

Abs unit went bad in my 99 so I don't have tc/abs just those dam yellow lights

El original

I also have a '03 Vert and recently drove my friends 99 vert, I also felt it was slower than my Corvette, don't know why either?!?

motomanvette

The 03' does have 25ft/lbs more torque, stock vs. stock.

02general

Don't the 03's have a bigger cam and better heads than in 99? That would explain the increased torque and HP numbers.

Vetteman Jack

GM specs did have the '03 faster than the '99 - so what you were feeling was the way it was designed to be.

calbrit561

You think 25 ft lbs of tq can make that big of a difference

Sonny71

5 less HP should not make a big difference, did the '03 have the performance axle?

Gordy M

A couple of items to check, does your 99 have the Pup Cats? Does the 99 have the original the O2 sensors? The only real test was if you happen to have some time slips and check the trap speed and 60ft times.

98C5P

Did you have the same size rear tires on both?
The run flats will be heavier.

ronwc

2.73 to 3.15

98C5P

^^^ all 6 spd C5s were 3.42?

blackmachdown

03 had the ls6 intake, 99 did not

RSbeast

Read the FAQs guys. Those cars are miles apart drivetrain and electronics wise. One is basically a z06 with 241 casting heads and slightly less gear; the 99...pretty much the opposite with early gen everything.

Very important to read up before you buy.

calbrit561

Yup i learned this after the fact i didn't think 25ft lbs would make that much of a difference

RSbeast

People get way too caught up on peak figures. It's how it acts over the entire rev range.

Those cars don't even share the same block/guts. After 01, GM started carrying over more and more from the Z06 into the standard C5. Not to mention normal yearly improvements within the drivetrain, the latest in the stability control etc etc.

It's literally shorter to just list the differences between an 03-04 Z51 car and a 03-04 Z06

Once you swap the exhaust out it starts getting fun. That's not to take a damn thing from a Z car; but 100-150lbs (most of it from losing the runflats and the exhaust), unported 243s are like a 20hp bump and the slightly extended rev range is nice at 6000 vs 6500 - but that's where the big split is. Touch more gear down low and a little more rpm goes a long way.

Just because C5s look the same, doesn't mean they have the same.

grantv

As RSBeast noted, AFAIK the later LS1 had a better torque curve. "HP sells cars, torque wins races" holds true here...
So your HP figure may be pretty much the same, but the newer engine has more power thru the RPM range.

DOUG @ ECS

I would consider data logging the car with any common scanner and see if the car is holding proper timing, does not have excessive knock and so on.

A 99 can be really carboned up by now, I have seen it many times. It kills the power of the car substantially.