I'm thinking about upgrading to LS6 intake on my 1999 Corvette, but have questions.

Do I need the injectors or just use the 1999 injectors?

So far the car is stock, but planning to add long tube headers, LS6 intake, just put on Borla cat back.

Thought with long tube headers and maybe catless X pipe(not sure if I can go catless or not emissions testing in Phoenix area), the Borla stingers, LS6 intake and maybe a cold air intake, mail order tune from ECS it should be a nice upgrade.

Could always get into heads and cam, and/or supercharger down the road, but thinking try the little stuff first.

I just need the LS6 intake and reuse my injectors and fuel rails right?

 

I did this on my 97 and it was a nice upgrade. You can reuse your injectors and fuel rails, however the steam tubes that exist under the intake manifold on the earlier LS engines either need to be swapped to the later steam tubes, or I’ve heard you can file groves on the underside of the new LS6 intake, creating a channel to make the stock steam tubes work.

When I did mine, I purchased the newer steam tubes for an LS6 engine.

 

I never changed my steam tubes OR filed the manifold for clearance. Just bolted the intake down. With an LS6 intake, 25% underdrive pulley, 160° stat, a non-dyno tune, no cats, through stock exhaust manifolds, Flowmaster mufflers, a Blackwing air filter, and a Granatelli MAF, my A4 2000, G92 3.15 axled Vert ran a best of 12.89@109.97 1/4 mile. It was always in the high 12s from then on.. These were all bolt-ons/take offs, and I never even checked the spark plugs. I think just about any C5 can duplicate, or better these figures. I eventually bought some Billy Boat shorty stainless headers, and a 3200 stall Yank converter, and got down to a 12.50@114mph. I say go for it........

 

Intake is definitely worth it.

While you're in there - get the LS6 valley cover too.

https://www.improvedracing.com/2004-...-swap-kit.html

Your injectors and fuel rail will bolt right up. I would personally keep your earlier four-corner steam tube. Some say you have to file the grid down off the bottom of the LS6 intake to make it fit, but it's been done.

 

12.89 with a 3.15 gear and stock heads and cam is very impressive.

 

Thank you. It was a pretty strong running car for a stock A4 C5. I later learned that the 2000 models had the highest lift along with the tightest LSA of any factory LS1 cams. That didn't hurt. I also think the Blackwing and tune did a lot, too. I never ran in the 13s again, always 12.90s, and that 1 12.89. I got blackflagged at Lapeer Dragway by the owner at the time, Ed. He was going by NHRA safety rules in 2004, and that meant any convertible running quicker than a 14.00 second et must have a rollbar! He asked me what the car ran, and I said I'd never raced it there before. My other runs had been in Ubly, and Milan, Michigan, so I was kinda/sorta honest. Well, I made about 3 or 4 runs before he came running up to the staging lanes!! He had that black flag rolled up so he could shake it at me like a pointer!!! And he did!!! Guess it didn't help that I skipped right through the 13 second bracket, as all 3 or 4 runs were in the 12s, including the 12.89!!!! He yelled "You're outta here"!! I used to race a drag bike there, ran high 10s-low 11s. I argued with him saying "Ed, I raced a dragbike here that ran 125mph+, and all I had were leathers and a helmet. This car is 15mph slower,, and is 10 times safer"!!! He says "You're right, but it's my track, and you're done here with this car setup like it is"! Oh well.....

 

Sounds like it's a good upgrade.

What should be the max price for a used LS6 intake, I see some for sell asking $400-600.00, seems too much, for that price range I think about just going for a new FAST 92, but that's probably overkill without heads and cam.

I see LS6 intakes for sale that seem like trash, ad says it needs repair on back and in pictures see pieces missing, maybe damaged in a wreck, or why the seller is replacing it.

MIssed out on one here for $200.00 which seemed like a great price.

 

They go for $3-400 used. Still half the price of a FAST92, and no need for a throttle body or an adapter harness.

I myself have sold two, relatively quickly, for $350.

 

Get the LS6 intake - it is a nice upgrade over what you have now.