Not a dumb question at all. And a big discussion point.

Coating will help two important things and one less important thing.

1) It keeps some of the heat from the primaries inside the primaries and not in the engine bay. That's a win all around, because the car will make more power and it's less thermal stress on nearby components like the starter, plug wires, and various sensors and wiring nearby.

2) It helps keep mild steel headers from rusting. It will help lower grades of stainless steel too, but that's probably less critical.

3) It helps keep them pretty. Coated headers look pretty to start with and stay pretty. You can get them done in different colors and whatnot too. This doesn't matter at all.to me.on my race car, but it's a factor for some people.

I did Eastwood internal header coating. It's an internal coating (most are applied to the outside), and it's very DIY friendly. I've used it twice and it's functional at reducing thermal transfer to the outside of the headers. This time.i used a header paint for the outside... Largely to hide my ugly welding, lol. But also partially because I was thinking about header wrapping them at first, and I wanted a layer of paint to protect the headers from trapped moisture if the wrap gets wet. Almlat all these coatings require a thermal cure (I think cerakote has an air cure coating too, but it has to be sprayed via a paint sprayer), that's not a big deal.on the Eastwood coating because it's inside and you can cure it with exhaust heat after being installed without any real issues with it coming off during install.

I decided against wrapping them because it's a race car, and the risk of the wrap getting soaked in oil or fuel was a fire risk. Also, the amount of wrap needed for them was more expensive than the Eastwood spray. So it was more work, a fire risk, more money, risked getting obnoxious wrap shards in my clothes and skin... But admittedly it does seem like the wrap rejects heat even better than a coating.


All that to say, yes, getting them coated is a good idea. Either inside via an Eastwood kit or outside via cerakote or jet hot or similar.

 

Since we're spending your money more, here's a few other things you buy.

ARP exhaust manifold bolts, get the 12pt stainless ones.
Starter blanket -helps keep heat off and make the starter last.
Better manifold gaskets, usually the ones that come with headers are the cheapest crap you can imagine.
Stainless lap clamps for the slip joints and high te.p exhaust gasket rtv.
Spark plug thermal boots or ceramic end spark plug wires
New spark plugs -since you're in there, may as well put some new ones in for $30 for NGKs.
A stud/bolt and spacer for the alternator and accessory support braces
Flexible Stainless steel dipstick tube, so you can move it as needed
A tune from PCM of NC or your tuner of choice will unlock more of your power gains.

Expect to either be draining and filling the coolant to remove the temp sensor, or buying a new temp sensor, possibly wire, and draining and filling the coolant to replace it when you break the sensor trying not to remove it.

 

I installed my OBX headers about 15 years ago and they still look great. My engine compartment stays noticeably cooler now than it did with the coated mild steel headers I had before them. I don't see any need to coat them.

 

I'll at least coat the inside. Thanks for the heads up on the Eastwood kit.

Will probably get a lot of what you suggested as well.
What part number for the 12 point arp bolts?

 

I bought ARP 400-1209 based on forum recommendations. They look like they'll work but I haven't gotten that far yet. Maybe Friday? I'm going to pick up 2x 3" stainless bolt at Lowe's, as well as the 1" spacer for the support brackets. Maybe 3, one for the oil dipstick as well.

One other thing I forgot to mention.... Heat d o2 sensors. Again based on forum recommendations I bought a set (because they were the same price as replacement 1 wires and appear to have no downsides other than needing to find.a switched power source in the engine bay). The claim.is the regular ones don't warm up to operating temperature with headers.... I dunno how true that all is, but that's the claim. I would think they'd get hotter with headers but maybe the increased scavenging means they don't get a chance to soak the heat in or something. I dunno, it was a no brainer vs buying new single wire ones though.

 

Thanks man!

I'm assuming I should buy 3 inch exhaust clamps?

Working very slowly. Got the exhaust and cats off. Started to loosen some of the passenger side header bolts.

My car has new spark plugs in it. Is it necessary to remove the spark plugs for header removal and install?

 

I would take them out so you don't risk breaking them. They're kinda in the way, and it's WAY more of a hassle to deal with the bottom half of the plug threaded into the head and broke off at y the nut than to just remove them, lol.

 

Good point. Can't believe I didn't realize that.

 

More slow progress.
Plugs are out
All but 1 passenger side manifold bolts are loose/out.
I found cylinder 8 manifold bolts easier to get to under the car.

 

How do we remove the oil dipstick? I had to force it out of the way. Hopefully that wasn't a mistake.

 

Bolt (well, stud and nut really) on the manifold, then twist and pull. It's just kinda wedged in there with an o-ring.

You're gonna want to take it off, lol. Ask me how I know...

 

Thanks, it came out.

Both manifolds off. Novice questions. Should I buy new oem gaskets and see how well it lines up with the obx LT's?



And of course, I won't reuse old gaskets.

 

I bought copper gaskets, I am less impressed with them than I was the MLS gaskets for my TBSS. The LS motor community says to trash the fiber style gaskets more headers come with (they have a thin foil puter layer that's perforated and black fiber cores). So imagine my surprise when I took my factory manifolds off to find exactly that. The OEM gaskets on my TBSS were several pieces of thin steel laminated together to make a great sealing gasket (I used the other gasket underneath it to ensure plenty of thickness for a good seal -the flanges on headers are often not perfectly flat and are sometimes slanted, so extra thickness is good).

The copper gaskets are decent. Two thicket layers of copper foil sandwiching a fiber core. I couldn't find any laminated steel gaskets like my Delco gaskets for the TBSS. So i stuck with the copper ones.

I really don't want to have to redo the gaskets once everything is installed lol. Getting the headers into position with the full exhaust system on them still sounds like a nightmare to replace the gaskets.

Side note, it's nice having a headers install buddy, lol. I'm like a couple hours of progress ahead of you, lol.

 

Man, loving the progress Question, this looks to be a LT4? Do you still have the OEM exhaust?

 

Thanks. Only the manifolds and cats.

@FAUEE Thanks again my friend

 

@James93ILT1 Hey, do we re use the brakets on the sides of the bell housing?


Also, do I test fit the headers with the stock bolts or the ARP bolts?

 

I would use the ARP bolts. The last thing you want is to over tighten the stock bolts and crack the heads or something wild. Plus if you get them in and more or less right, you're not gonna want to take them back out, lol.

My 92 didn't have any brackets on the bell housing, so that was nice. Based on that I'd probably skip them.

That said people acted like I was crazy when I asked about the spring mounts around the mid muffler, so if you don't have those mounts I'd probably want more support than just the header bolts and the two mounts in the back for the tips.

 

Those brackets are a pain to remove! Especially the upper bolt on the driver side. But I'll get it out. And yes, I do have those spring holder things for the exhaust.

 

I did not reuse the brackets on the bell housing. I removed it, when I had my bellhousing off.

I test fitted my headers with the header bolts that I bought.

 

Excellent, thank you very much!