rcwilbur

I have a 99 C5 and am going to install LG Street Headers sometime over the next week or so. I looked at the bolts on the stock exhaust manifold and they are rusted but don't look too bad. Any suggestions about removing them to make sure they don't break? I assume lots of PB blaster and some heat?

Also are they bolts or studs and does anyone know what size? As long as I have them off I would like to replace them with new bolts/studs.

Thanks

rnelson11

My Kooks headers came with new bolts. It says on the bag 'M8X25 Flange Bolts'. They are for a 2004 LS1 but sould be the same.

rcwilbur

Thanks. I'll wait to see if the LG headers come with bolts. Did you have any diffuculty removing the stock manifold?

Bill Curlee

Ive reused mine dozens of times and never once had a problem removing them or reinstalling them. Just buff them up with a wire brush and they will clean right up. Just make sure that the engine is cold before you remove any dissimular metal threaded fastener.

rcwilbur

Thanks. Did you have to use any heat? I've heard horror stories of having studs break and then trying to get them out. Was a little worried abou the bolts.

NukeC5

Where are you located? Bolts are horrors to deal with in cold wet climates as they are prone to rusting and can become brittle from constant hot and cold fluctuation. Down here in southern cali and dryer warm climates, people find bolts to be a piece of cake. Not the case for me growing up in Oregon. You knew, any bolts coming off the exhaust where going to be toast. (At least on older cars).

rcwilbur

Central Illinois. I just bought the car this summer, but it has been in Illinois virtully its entire life. Bolts don't look too bad but don't want to break them and end up with a project I can't complete.

tentuna

Replaced mine with Allen key more clearance around the headers than socket heads and it looks cleaner.

Bill Curlee

I have never had any issues at all. They just came out with out any problems. No heat, No corrosion, no issues and I live on the coast in southeast CT and drive my car in the winter (when the streets are clear)

rcwilbur

Thanks Bill! I guess I was a little leary after disconnecting the h pipe at the manifold flange and the very first stud snapped at the flange. But I understand those are much softer bolts. Thanks again.

rcwilbur

Bolts came out without a problem. I thought about replacing them with new bolts until I called the dealership and they wanted $2.50 a bolt. Old ones are fine.

mighty mousd