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The answer to get you to the RWHP you want is a Vararam, a mild cam, long tube headers, AND A PROPER TUNE (very important). That will put at 400 + to the rear wheel.
I'm in Kaulifornia, and long tube headers are hard to smog. For the same money(I had it installed), I put in a 3.90 rear axle from DynoTech Engineering.
HP is the same, but the low end torque is unreal. I did a before and after 10-60mph test and it went down .9 secs. That's HUGE.
But there's nothing like the sound of a good exhaust with LT headers.
Good luck.
absolute is possible. The GOOD tuner will get more out of stock set up then all the bolt ons.
When the bolt ons are there as well, that may be good for an additional 10.
LS6 with the RIGHT tune, ~ 370-375 hp, with 100 octane 380-385 hp
LS6 with all the bolts on the world, No turbo or N2 and not going inside the engine, with out tune 350, with tune 380-385.
all rwhp.
wont see 400 rwhp with out a cam and head work
for an LS1, take out ~ 30 hp less, do the LS1 cam and valves
On an LS6 it might be possible. I think the thread starter has an ls1. I would be very interested in seeing a STOCK c5 LS1 dyno sheet showing a gain of 42.5rwhp off of just a tune. This would equal 50 at the crank. It would of course need to be realistic. I dont know anyone running 100 octane other than FI cars.
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No need for bigger injectors unless you get a Cam change and Heads!
Then I would do Long Tube headers with Hi-Flow Cats and a Dyno Tune!
This would net you the most and is cost effective
Thanks,Matt
which will give me better performance, a CAT back system or long tube headers. Obviously both would be the best, but let's assume I only have budget for one or the other.
I run 100 octane. Just about all the road race corvettes run 100 octane. In the SCCA the LS6 and LS3s must be stock, but can run 100 octane and can be tuned.
What are the most cost effective performance mods to get a 345 hp LS1 to about 400 hp? Assume my time to install parts is worth something too, about $50/hr. Also assume I don't have a lot of free time. NOS is not something I would consider.
What mods should be performed to pick up about 50 hp?
-Cold Air Intake?
-Larger Injectors?
-Aftermarket Programmer?
-Ignition Controller?
-High Flow Cats & Mufflers?
-Other Suggestions?
I appreciate your suggestions.
Cost effective PERFORMANCE Mod would have to be a set of 4:10 gears.
I am counting the day's until I order a set ( 5-600.00 ) and get them installed ( 800-1000.00 ). I was just in the same car as mine 2002 vert with 6sp and those gears felt like another 100 hp at the wheels.
For about 1600.00 its the best money for the WOW factor!
If you're going to buy headers, get a header & x-pipe package
American Racing
Kooks
LG Motorsports
All make quality stuff.
As far as a Cat-back, get what ever sound you like to hear. The stock Z06 Ti performs very well and you can buy used sets here. For that matter, you can buy any brand used here if you are patient.
Also get a vararam air intake (or what ever you personal choice is.)
There are several good shops that you can send your computer to and they will retune it and send it back to you. Not quite as good as a dyno tune, but pretty darn close. It's usually about $150 -$200 for the service
If you're considering headers in the future, just be careful which catback you get. I went with Corsa Xtremes which sounded great with the stock manifolds/cats, but are borderline obnoxious with th AR longtubes and x-pipe. Idle is only slightly louder, but once you get into the powerband, they can wake the dead.
which will give me better performance, a CAT back system or long tube headers. Obviously both would be the best, but let's assume I only have budget for one or the other.
If it's the budget then your best bet is to go with Cat Back first - you will need it eventually anyway - why run stock restrictive exhaust on LT's, Hiflow cats and X-Pipe
Get yourself a good set of mufflers and start building from there it is a perfect starting point
You looking for top end or the occasional stop light Gran Prix? For top end, do the things outlined. If for the latter, put in a 3.90 or 4.10 rear end and have the car tuned. You'll need good rubber and probably need to relearn launching to hook up and avoid laying down lots of $ every time you get on the loud pedal hard.
I think that you have a great place to start. However I added the x-pipe and high flow cats to the header package, and highly recommend them.
Here's a better price for a tune at a place that has more C5 experience. (link)
If you wanted a budget cat-back, you could always pick up a titanium Z06 system for ~$400 that will also save you several pounds and last forever.
Good luck!
Just get a custom tune and don't waste your money on a Mail Order or Hand Held.
I have installed a few LG Streets and IMHO its the best header for the money. Fit and Finish are great. You should include the X pipe for a 100% bolt on install. If you do the off road pipe you'll need to have the rear O2s tuned out.