Ebay Headers Question

[Bearcat91]

I would suggest getting new hardware to go from headers to y-pipe, as well as new hardware for securing headers to the engine, the ones I got seem pretty cheap-o and I have decided I won't be using them.

what hardware did you get?

 

[jcoatswo]

I didn't get new hardware for the y pipe, still using what came in the kit. I just went and bought lock washers and put them on the 6 bolts to each head from the headers.

 

[94Sierra4x4]

what hardware did you get?

Will be going with Stage 8 locking header bolts, I'm not sure if I can use my exhaust springs/bolts/nuts for y-pipe to header, but I have new ones set aside at home anyways.. waiting on parts before I start..

You'll probably end up retorquing them soon. And for the y-pipe you should most definitely double nut it.

Also some information I heard about "Cheaper Headers" .. Do not over torque the bolts around the center 2 pipes, it will cause the flange itself to warp and will leak through the gaskets.
Something to keep in mind anyhow.

 

[jcoatswo]

Thanks for the info!

 

[zilverado71]

Step 1 remove headers
Step 2 grind down the sloppy weld they left on the mating surface in the manufacturing of the headers.
Step 3 buy cheap "drop on" gaskets. Good ol' tin colored drop on gaskets.
Step 4 clean head surface perfectly with "cookie wheel"
Step 5 Brakleen all surfaces
Step 6 use HIGH TEMP RED rtv silicone on your header surface. make a 1/8inch tall bead all around it. smear nice and pretty with finger, without lifting your finger off till your done, so you don't make bubbles.
Step 7 use silicone on heads, now.
Step 8 with silicone still wet, put two bolts through header and install it with gasket smeared to the HEADER, laying on the RTV, inline with the bolts so it is lined up.
Step 9 using 3/8 standard header bolts (buy them from oreilly auto parts) tighten in a middle to outer pattern. try not to fumble around too much with the silicone when you do this
Be sure when you tighten, to hold your finger from the gasket lifting up. They sometimes lift when tightened.
Use ANTI SIEZE on your header bolts. This will prevent them from vibrating out, and also seizing and corroding. LOCTITE however useful at times, will not work for this. You can start your engine immediately when your done. but do NOT hit the throttle. let it idle till the engine is warm, (195 degrees warm) then shut it off. When your temp comes down to room temperature (not warm enough to show up on your guage) you are completely done.

Your welcome.

 

[jcoatswo]

Great guide thank you! I do have one more issue, I've been driving around for about 2 weeks now (to make sure I'm not just crazy and what I see on my gas gauge is actually happening) and it seems that my gas mileage is between 6-10 mpg... even on the freeway!! This is killing me! I can literally watch an eighth tank disappear on my way to work, 17 miles all highway... Granted I'm only used to about 12-14 mpg, this is a HUGE dent in my pocket. I will be following zilverado's steps next weekend when i have some spare time and cash. Does anyone know what this could be? Would I need a new/different o2 after this header install?

 

[94Sierra4x4]

You sure you don't have any exhaust leaks?

 

[jcoatswo]

I know I have a leak at the header to head. But its not bad enough to cause this kind of a problem. I double gasketed the header for the time being, there is no visible gap, but you can feel exhaust leaking if you put your hand near it. I see no reason for a tbi motors gas mileage to halve by a small exhaust leak.

 

[94Sierra4x4]

Losing power, not as free-flowing, more gas to get you going, it will hinder gas mileage

 

[jcoatswo]

Ok, thanks. Ill try to fix is right this weekend and come back with an update.