My 79 L82 previously had the cats removed and new 2.5" dual exhaust added from the ramshorn manifolds back including high flow mufflers; I'm doing an EFI swap this winter so I decided to buy headers and just have the O2 bungs welded in to the new headers before they get installed.


I bought the FlowTech 1 5/8" ceramic coated 31106FLT headers today and the AC bracket for them; not sure what else I need... -Bought them from Advance Auto Parts because they're having a 15% off sale right now so they're only $274.66.

What else do I need?
-Do these usually come with bolts to connect them or do I need to buy header bolts? (Initially they'll be installed in the stock heads- and aluminum replacements later)

Do I need a gasket? They say they come with orings which seems very odd...



Adam

 

I've already got the Steeroids rack and pinion set in the garage, too; so I bought the FlowTechs because they're supposed to fit perfectly with the Steeroids. If anyone has any reason to believe this is NOT the case, please let me know ASAP.


Adam

 

You will need the reducers that go from the headers down to the 2 1/2" exhaust that you have.
I have a spare set of stainless ones you can have for $15+USPS flat rate shipping.
You can have the bungs welded into the reducer instead of the collector of the header. Keeps the header from rusting out.
I need to find my old pics or take a new one.

Let me know if interested by PM.

Txs
Dennis

 

Pics of reducers

 

The headers that I have purchased new usually have the installation bolts and gaskets included. The gaskets that are included usually aren't the best quality imo. I use the 1444 Fel Pro gaskets. They are steel core laminate over gasket material. There is a variety of opinions here on the gasket that should be used. Some use soft copper gaskets. Others use two gaskets etc.

 

@#$%^#@$^!!!! I hate it when I make newb mistakes like this... I thought that meant that the collector was 3" long for some reason -which would've been better for perf, technically right? (I wrote down somewhere that a longer collector is better.)

I guess it's not a terrible mistake and like you said it does mean I don't have to have the O2 sensor bung welded into the header and compromise it's rust-free coated nature, so maybe it's a good thing.


Are you sure those adapters are stainless? -They're pretty black in color. They screw into the end of the headers and then have to be welded into the existing exhaust, on the downstream exhaust side, right?



Adam

 

On the exhaust bolts issue: I thought I remember there being special considerations when using aluminum heads as the difference in the rate of expansion between aluminum heads and iron/steel manifolds causes the bolts to work themselves out.


On the gaskets, I don't really want to wade into the controversy too much; any real-world 10+ year experience with a gasket and bolt combo that doesn't leak is good enough with me.

I'd also really like a recommendation for a gasket solution that I will be able to get installed in the next month or so, and then have a good chance of being able to remove it and transfer it onto a set of new heads without damage about a year from now- if such a thing is possible.


Adam

 

Whatever type of gasket you choose to use, it is very important to retighten the bolts that attach the headers to the engine after a few heat cycles. Doing this ensures leak free operation. I also tighten the collector bolts as well.

 

Shockingly enough, I actually knew that, but I do appreciate the reminder and capturing all the recommendations here in one thread for future readers.


I'm guessing that using Loctite would be a bad idea as I AM going to need to actually remove the bolts after a top-end swap roughly a year after installing the headers... (Just figured I'd explicitly ask the question, because when I assume I make an *** out of me; as evidenced by my misread of "3 inch collector"...).



Adam

 

Also, with the coated headers, will I still need heat-resistant boots for my spark plugs or does the reduction in heat from having coated headers make that a non-issue?


And, hopefully my last question for a while: As I'm planning a full new top-end (heads, retrofit roller cam, new lifters and intake), what do I do to ensure that I don't let the engine assembly lube destroy the headers' ceramic coating? -I've read that assembly lube will destroy the coating and cause them to rust and lose their heat insulating abilities to a certain degree. Do I just keep the original iron ramshorn manifolds around and then when I do the top-end swap unbolt the headers and bolt back on the rams horns and just let them dump exhaust straight out and into the engine compartment for a few miles and then swap back on the headers? How many miles should I wait to "burn off" all the assembly lube with the manifolds on before putting back on the headers?

Hmm... My current planned order of modifications is to do the headers now (and plug the O2 bung hole with a spark plug until I do the EFI swap), then do an EFI swap this winter with the stock L82, then next fall->winter do the top-end, but if I have to swap for the ramshorn manifolds to avoid the assembly lube destroying the header's coating I then don't have a place to insert the O2 sensors while running back on the manifolds... -What the heck do I do there? (The EFI won't even work if I disconnect the O2 bung, right?) --Am I going to have to switch back to the Quadrajet and old-school fuel pump while running the manifolds? -because that would be super painful...

CRAP... I seriously don't know what to do- even if I just bolted a small adapter to the end of the manifolds that wouldn't work because the O2 sensor would still be exposed to air coming in from the back of the tube and it would totally throw it off... I wonder if these have some sort of "safety" mode that they can run in without the O2 sensor for a while... (I'm planning Holley Sniper but it's not released yet so it's hard to say what it does and doesn't support but a stripped down version of the Holley options is highly likely.)




Adam

 

I agree with ss here, you need to check the tightness of the flange bolts after the first 3 or 4 heat cycles and should do this just as the flange gets cool enough to touch with the bare hand. Be super careful not to overtighten as thus can warp the flange and make containment of the exhaust gas at the flange a bitch. A stud kit for the flange at the head is the way to go and you can double nut the stud, preventing accidental loosening.

They throw the disclaimer out about the break in and destruction of the ceramic coating, but I've broke in two engines with them and have had zero issues, one of the break ins was a flat tappet camshaft, were once it's started its imperitive to run it in for 20 to 30 minutes at 2k to 3k rpm which generates a s4it ton of heat as the lifters are pumping up and the timing slightly off, you'll be fine, if your going flat tappet camshaft having everything right you can be fore start up is key. I'd also sand a small spot and put the o2 sensor in the collector.

 

I just looked at ARP header studs; what's the diff between the black chromoly and chrome? -Just aesthetics? Hex vs. 12 sided?

I'm going to ask Summit / Jegs support about breaking in a new engine and ceramic header coating and just how long they want you to run with manifolds on before switching back to the headers.

I asked on the Holley site and found out that their EFIs do support running in a non-feedback loop mode and just "locking in" the current tune- it's mostly designed to allow you to keep running ok when your O2 sensor gets screwed up, but it would work for this scenario EXCEPT THAT when I switch from the stock top-end to the new top-end the EFI tune would be completely in appropriate for the new heads, so I think I WILL have to for 5 minutes or so run the new heads with the headers and normal exhaust on to get my EFI retuned for the new top-end (and do the cam/hydraulic roller tappet break-in). THEN I can shut everything off and set the EFI to just "hold" the tune without EFI, take the headers off, and then put the stock manifolds back on for the 2,000 miles or so I'm guessing they're going to tell me to run with manifolds to avoid ceramic coating damage. (I can rinse out the headers then if that'll help at all.)

I could be living with this car for another 30 years so I just don't want to chance it.


Adam

 

So Summit said it's really the first 30 minutes / couple of hours that's the most critical and when it'll pass the most engine lube gunk through to the headers so I guess the process would be to just assemble the new heads with the stock manifolds on it and do the cam break-in procedure for the 30 minutes or so (and hope that the original EFI calibration will allow it to run "good enough" to get up to RPM for 30 minutes), then let it cool down and do the initial oil change and put back on the headers and then recalibrate the EFI.


My initial best guess was totally wrong to try and do the EFI tune and cam break-in with the headers on; it's the first few minutes that are the most critical and when getting the headers off would be most important.


Adam

 

Hi Adam
Just going by the side of the box. These were never out of the box until I opened them for pics. Good questions though.
These do attach to the header flange with the gasket shown, the sliding flange holds the reducer and of course the bolts clamp it together.
Make sure to semi assemble them before adding the bung for the O2 sensor or you will not be able to get the sliding flange on.
You can have them welded to the existing exhaust after assembly or go with clamps...your choice.
I'll double check the steel but at this price they are pretty cheap. You can see how thick the reducer pipe is. And unless you have stainless steel exhaust all the way back, these will match what you have.
Good luck with your project.

There are no stupid (newb) questions, only unasked ones....so ask away.
Better to find out now than later.

Dennis

 

There should be no assembly lube coming out of the exhast port, if there is there is something wrong. I researched this very thing like 7 years ago and all I could find was in association with the heat of break in and running in a flat tappet cam. How would assembly lube come through? It's not like you rub the cylinders down with it.

 

Figured out why the exhaust parts are blackened -400 series stainless. (I'm so used to the non-magnetic, shiny 300 series.)

Adam

 

I don't know but every header company and major reseller has warnings all over the place about exactly this so I am still mildly concerned...


Adam

 

Hi Adam,
PM sent about reducers.
Dennis