Finally doing bolt-ons after 2 1/2 years of ownership just order a set of speed engineering 1-7/8in long tube headers. Should i change spark plugs and spark plug wires when adding headers?
If so what do you guys recommend? Also adding flex fuel kit if that matters. Doing the install myself so any advice that will help would be appreciated.

 

https://www.corvetteforum.com/forums...s-to-help.html

That thread has some good advise for doing the install.

 

Yes, I would change them while installing headers because it will be apart now. In regards to which plugs it depends on the motor. Do you have a lt1 or lt4?

 

LT1 oem plugs. Changed them about 20k miles ago

 

I would change plugs and also get the insulated plug wires due to the increased heat rejection of the headers. Chances are you have to remove the plugs and wires for access to the exhaust manifolds anyway, so just change now, instead of later. DEI makes nice insulated socks for the wires.

 

unless you have some what over 50,k miles on them I wouldn't not chg them. Robert

 

I had to use Acel ceramic boots because my wires laid directly on the header pipes just insulation wasn't going to work

 

My #1 recommendation: Use an ARP header stud kit

 

This ^^^^^^^ stock wires are fine and unless you have high milage on your plugs they are fine also , all I did was put the heat resistant spark plug boots over the wires

Dave

 

• Use ARP bolts with Anti-seize, torque properly
• Use MSD plug wires, do not reuse the factory plug wires
• If low miles and the plugs look god you can re-use, but while you're there why not just replace with a good set of NGK iridium or factory plugs. Keep the stock heat range.
• Fit everything on the car loosely, then tighten front to back. Headers first.

 

when using anti seize on the header bolts should i be reducing the torque values or stick with OEM numbers?

 

Don't use a lot of anti-seize and maintain the torque specifications within 1-2 lbft

 

The shop that did mine recommended to keep the OEM wires, they run them on all of their builds including the 900+ hp LT4s they've put together so I have the stockers with my 2" LTs. They changed the plugs to a step colder because I was also upping boost via upper pulley change at the same time as the headers but normally they would have left the plugs alone also. The heads on the stock wires will get looser the more you remove/reinstall them and you need to make sure you have them snapped on all the way when you reconnect them after the headers are done. The MSD wires are very nice with headers though because they have a flexible head so you can angle them away from the headers a bit easier. Either way, I'd do the DEI lava sleeves as suggested above to protect the wires from touching a runner and from the heat generated. I think it's up to you but with 20k miles on the plugs I'd probably swap them for a new set. Wires are up to you, the MSDs aren't that expensive and neither are the sleeves. If the plug wires are close to the runners you may want to swap them so you can angle the wires away for more clearance.

 

I’m doing mine now also. There is a nut on each of the cat down pipes that are a pita. They are the ones connected to the manifold. I couldn’t get them loose using all the tips people said. Finally I took off the manifolds with the one nut left on each one. At that point I was able to manipulate the down pipe enough to get my impact on both of those nuts.