General ET/HP Database-What's your 1/4 mile time?

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Table of Contents

• OEM HP/TQ Ratings: Y Body, Fbody, 4.8, 5.3 and 6.0

• General

• How much power am I making?

• What will I run?

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OEM HP Ratings

The ls1 is underated from the factory. This is proof of just that. Also note there is no significant difference in power between an ls1 corvette and any other ls1 powered vehicle. GM did this for marketing purposes.
All times are driver specific, such as if you can't drive you won't be pulling these times.
The corvette differs from the F-body in a few things. It is lighter, weighing in near 3200lbs (empty) [zo6 is around 3100lbs (empty)] vs. the F-body's 3600lbs (empty). It handles better, due to less weight, lower center of gravity, and better suspension (IRS). IRS makes launching a Corvette more difficult that is why they pull similar times at the strip. In a roll race or a top-end race the corvette *should* win, given equal drivers. Basically if you are buying one of these cars solely on performance to price ratio, there is no question an F-body is for you. Find the least optioned F-body (cheaper and lighter) and go to town. If pleasure and the factor are for you get a Corvette if you can afford it. Some people prefer F-body's over Corvette's in looks so basically get what you want for your specific purpose.
Don't let someone persaude you into getting something you don't really want; because they aren't going to be spending the money for it, nor are they going to be driving it!

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General

Let me start off by saying that different combo's will have different power outputs when paired correctly. You can't just add A(15rwhp) and B(20rwhp) together and get C (35rwhp). This is especially important when buying cylinder heads and a cam. These two things are very important to do a lot of research.

To make things easier here you go:

Pay special attention to the posts made by Jrod if you aren't into reading a whole lot.

• Cam Guide

• Cam Discussion I

• Cam Discussion II

• Cam Discussion III

All Intake/Exhaust mods can be viewed Here as well as a description of each one and what you should look for when choosing one.

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Intake

Free mods - 0-5rwhp

Lid - 5-10rwhp
Install

Big article on lids and dyno comparisions here

Filter - 0-5rwhp

MAF -
Very controversial as to any real gains, may even show negative numbers due to the fact it will be tricking the computer to run lean due to the larger diameter of the housing (good for stock, since you will gain a few hp by running a little leaner than the factory slightly rich setting; however, bad for modified vehicles). Stock MAF's are good to 500+hp. Once you are beyond that I suggest you contact your tuner (or local speed shop if you are doing your own) to find out what they recomend. Some will suggest taking the maf out and doing a speed density tune, which relies solely on the front O2 sensors.

Lid, MAF, Filter Install

LS6 (ZO6) Intake Manifold - 10-15rwhp
Install Graph

Holley Intake Manifold - 15-20rwhp

FAST 78mm Intake Manifold - 15-20rwhp

FAST 90mm Intake Manifold - 20-25rwhp

Sheet Metal Intake Manifold - 25+rwhp
Mainly for all out race engines or bigger CI engines.

Testing of Intake Manifolds Here
Also note that these hp figures can vary greatly due to cam size and head flow.

Ported Stock Throttle Body 5-10rwhp
Install

Cold Air Induction (CAI) - 5-10rwhp

Nitrous - Typically the size of the jetting will be the horsepower increase. Some company's rate it in flywheel and some to the rear wheels.


Exhaust

Listen

Cat-back - 10-15rwhp

Duals - 15-20rwhp

Catted y-pipe 5-10rwhp

ORY y-pipe 5-10rwhp

Shorty Headers 5-10rwhp

Mid-Length Headers 10-15rwhp

Long Tube Headers 15-20rwhp

Misc.

Underdrive Pulley 5-10rwhp

Tune 10-20rwhp

Electric Water Pump 5-15rwhp

Please DO NOT take the maximum number for everything and add it together and think you will gain this by adding these mods.

Your average full bolt-on (Intake/Exhaust) Should net you around a 50-70rwhp gain, depending on how well your car responds to the mods that you do. I believe the highest bolt-on dyno is upwards of 380rwhp 390ft/lbs.

Stock dyno's range from 290rwhp-315rwhp. Automatics will dyno considerably less than a manual. Also such things as lightened flywheel will free up some hp as well. A bigger rear-end such as a 12-bolt or a 9" will show negative gains on the dyno. But you won't be breaking anything and you will run a faster e/t due to the better launch you can have.

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What will I run?

1/4 mile Calculator

Enter in weight (3600lbs stock) and enter hp number. It takes flywheel hp to be accurate so adjust manuals by rwhp * 1.15 = ~flywheel hp. For automatics - rwhp * 1.20 = ~flywheel hp.

To be even more accurate look at this database and find the times closest to yours. Then look at the modifications they have by clicking on the model of the vehicle (blue). Keep looking around until you find a car with similar mods. Then you can have a fairly good guess. Do not just go and find the fastest time that has your mods. Make sure to take in consideration the weight (reduced) and the tires (drag radials/slicks). These can drastically affect the way the e/t will be. Just try to be honest with yourself and you should have a good idea of what you should run at the track.

If you want to know for sure take it to the track!

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A section for cams and possibly heads may come along later, I figured I'd get this up ASAP. If you have any information to add, notice errors and/or incorrect info, links dont work, or you think this is of no use to the site PM me. Thanks.

LS1Tech Staff Member,

Kevin