Have some Kooks on the way...hopefully it will be my project for next weekend. Can't wait to get'em in and go for a nice long drive.

Any tips from those that have already been there done that? I've done several searches but I believe most of the posts are contained in the archives that aren't back online yet.

Thanks in advance!

 

Remove starter, Alternator, ,oil filter (only a little oil will come out, no need to drain), coolant temp sensor (have a plug handy to minimize coolant loss) and steering shaft. Tape off the brake booster with several strips of duct tape

Remove old manifolds: Easy

Start with the passenger side removing the lower 18mm engine mount bolt on the bottom and loosening the drivers side mount bold with only a couple threads holding it on. Jack the motor up from the passenger side as far as you can without risking cracking the windshield.

Repeat for the drivers side (remove the drivers side mount bolt, replace passenger side with a couple threads) You will need a helper under the car to pull the header in place while you use a 2X4 or 2X3 to insert between the frame rail and alternator bracket pushing the motor over even further.

Watch out for the oil pressure sensor, bolt them up replace all you removed and your done. MAKE SURE TO TIGHTEN BOTH STARTER MOUNTING BOLTS TO 38FT/LBS BEFORE TIGHTENING THE PASSENGER HEADER.

 

get ready for a 10+ hour pain in the ***. if i was u id pay some1 to intall them.

 

Went through the same thing recently. One note. You need to have the passenger side header hanging down while you reach up in and install the starter. This is before you bolt the header to the head. Otherwise you won't be able to get it in there.

In my case, I also removed the alternator bracket as well as the Alt. To do so, it's much easier to use a power steering pulley removal (and install) tool (Advance Auto or AutoZone). There are 3 (13mm) bolts that hold the power steering pump to the Alt bracket. I removed these and the 4 bolts holding the alt bracket on. It made life much easier.

 

HurricaneZ,

Thanks for the input.

I'm a little confused on this jacking the motor idea. Doesn't this torque the crap out of the drivetrain in the rear of the car as well, i.e. via the torque tube? So what exactly should I look out for regarding the windshield issue. Is there a place where it shouldn't be allowed to touch? Any tips on the best place to put the jack when jacking the motor?

Sounds like you installed the drivers from the top, is that correct?

Thanks again....

 

S1K C5,

Yeah, thats what I've heard but since this is a hobby the DIY part of it is half the fun. Gonna "try" to have fun doing it.

 

I installed both sides from the top. With jacking the motor, I placed a hydraulic jack under the engine and used a 4x4 that was about a foot long and put it between the jack and engine (vertically). I then jacked up each side of the engine until the rear of the engine (looking down at the intake manifold) just comes up to the top of the firewall overhang. Stop!

The engine tilts no problem with the mounts removed from the bottom. Leave the bolts on just a few threads. They are accessible directly from underneath. I think they were 18mm and with a deep socket you can get them pretty easy. You probably want to remove or loosen the air bridge also so as not to put any stress on the front.

It sounds like a lot, but it really wasn't that bad. And air ratchet really cuts down the time. The biggest PITA to me is the drivers side rear header bolt. I have found it easier to have someone hold the header up from underneath and then start the rear bolts first. Then stick a bolt in the front to level the headers. Then the rest of the bolts. Snug them all first, then work in a pattern to tighten them all down.

With kooks headers I have found that you need to use paper gaskets to seal properly. The ones that come with it work ok. I have found steel gaskets to leak.

 

78,

Factory gaskets are steel, right? LAPD says they like the factory gaskets better. I guess it may depend on each car, header flatness tolerances etc. - thanks

 

well keep at least 2 or 3 days open, if you dont have a lift your gonna be in trouble

 

I paid to have it done, it wasnt worth the headache

 

read and follow directions...use factory steel gaskets

 

Other than a new set of factory gaskets do I need to buy anything else?

 

You can use your old factory manifold gaskets if you want. I used the ones supplied by Kooks. I had to drop the headers about a month later and the Kooks supplied gaskets not only cracked upon removal, chunks were burned onto the heads and header flanges. I had to scrape it all off and put my old factory gaskets back on. You may want to pick up a water temp sensor and an oil temp sensor. They are pretty easy to break when trying to muscle the driver's side tubes in. Also, put duct tape on your brake booster canister, and take the alternator bracket off. I didn't, and it added a lot of extra time, broken sensors and busted knuckles (and swearing), trying to fit them in. Also, pick up some aluminized high heat foil wrap, about 2" wide. The clamps that fit over the xpipe to rear pipe connection are a slip fit and don't clamp all that tight. I wrapped it under the clamp a few turns and that helped.

 

Installed mine as part of a H/C package. Great fit and no ground clearance issues. A very good product in mho.

 

I've installed many sets of Kook's headers on C5's - although I've always done a H/C swap during each of them so of course this made the job much easier.. Even with the heads off I had to jack up the passenger side of the motor to get them to go in. I had to do this whether it was a set of 1 3/4" or 1 7/8". All installs were done from the top with the car on jackstands. I never had to remove the starter, but then I've never done an install with the heads still on the car..

I agree with someone above, do NOT use the Kook's supplied gaskets. I never even thought of using these because of the example above.. I just knew that would happen sooner or later. In every install I've done I've always reused the original metal GM gaskets with no problems what so ever.. Why they even supply these junk gaskets with such a nicely packaged header kit I have no idea.

You'll be happy with them at any rate. They fit perfectly in every one of my installs and I'll be getting ready to order another package this week for a client. They make great power

Here's a video clip of my 1 7/8" Kook's through a rather "free flowing" exhaust

http://66.230.217.253/videos/vette.WMV

 

Thanks for the info 99....that video is sweet.

 

You'll need the folowing gkts.
(2) GM#10276792 cat back flange gkts.
(2) GM#12558573 exhaust manifold gkts. These are from a older LS1, I believe 1998 and have the round exhaust ports. Do not use the newer LS6 or LS1 gkts #12576221 as these are square port and will leak!
(2) Gm#12553617 air tube gkts.

Remove the following; FRC's, coil packs, alternator, spark plugs, old exhaust parts, oil filter and steering shaft( Just take the one bolt out and move it to the side,Make sure you use Loctite on the bolt when you reinstall the bolt on the clamp), undo the starter and let it hang til the pass. header is in place , not bolted, and then reinstall.

Also, I wouldn't chance it and would remove the oil temp. sending line from the oil filter housing. It is a 2 bolt flange with an o-ring flange gkt and reuseable. Takes seconds to remove and reinstall.

I have done both Kooks and LG and did not need to remove the alternator bracket. I used it to pry the motor over when installing the drivers side header. Use a 2x3 approx. 3 ft long.

I also only unplugged the coolant sensor and left the fitting. It is not really in the way, just be carefull.

I have done both sets from the top with the cars up on Rhino ramps and jack stands at the rear body lift points. put another set under the rear suspension for safety. You won't be able to get the rear cat back off without cutting but if its not a Z06 Ti, no big loss.

Take your time, help may be needed for the drivers side. Take the nut off the drivers side motor mount(from the bottem) and leave the pass. side nut on a couple of threads. Jack up the drivers side as far as it will go, the cowl will start to lift once the intake makes contact. Gently pry the motor over towards the pass. side with a 2x3 between the frame and the alternator bracket. Have someone under the car to guide the header in while you work it from the top. It will go. Repeat for the pass. side. It is easier and you won't need a 2x3. Any questions pm me and I will get back to you. I have digital pics if you want them.

Have fun, its not about the money, its about working on your own car and having a better understanding of how these things work after. It's only nuts and bolts.

 

Hey 99blackfrc, what exactly do you mean my free flowing. I listened to them and they sound awesome. I wanted to go the 1 7/8 inch and without the cats. So if I go with that will it be that loud with say Borla quads. Thanks, Josh

 

Sounds like straight pipes to me...and some serious ponies.

 

It's the Borla XR-1 tail pipes bolted up to the Kook's 3" X-pipe with no cats.. I no longer run that setup though as the resonance was unbearable for daily driving. I now run mufflers with electric cutouts..

97vette,
One of the installs I did was with the Kook's 3" (no cat) X-pipe and the Borla quads. It sounds really nice.. Not too loud with a deep rumble. Sounds scary at WOT Exhaust tastes vary from person to person though so I'd recommend listening to it before making the plunge..