Exhaust - Headers, Collector, Pipes

[elspanishgeek]

I sound like a broken record with my posts but again after spending considerable time reading every thread I could find on my question, I find myself needing some clarity before moving forward, this time with the exhaust components. I'm gonna break it down in 3 parts, A, B, and C, which match the picture I'm attaching:

vnue9qZh.jpg
For reference, I have a 347 SBF from BluePrint and the 302 SS 4-port headers from FFR with ball collector (FFR Part 16757)

A) Engine to Headers
Seems like this one is truly a divisive topic, with 49% of people doing gasket and no RTV, 49% doing RTV no gasket, and 2% going gasket and RTV. I felt pretty good going with the Remflex #3028 gasket and not RTV, but after testing the Mr. Gasket ones that came with the FFR kit against the BluePrint engine, I'm worried if the shape of the ports just won't give me a good seal and I have to go with RTV.

Here's a picture of the gasket placed against the exhaust port. Is this difference in shape OK and can I proceed with the Remflex gasket?
PGni4VRh.jpg

There also seems like most people had issues with the bolts here and that the best options are from Stage 8, Percy's Vibe Lock, and ARP. I can't find Percy's anymore and too many people complain about the pain in the *** that Stage 8s are. One of the things I'm trying to understand is if the PITAs are the half-moon ones and not the tear-drop ones. Does anyone have any experience with these?

Lastly on this, what type of anti-seize or thread locker to use on these header bolts. The engine has aluminum heads and looks like Stage 8s and ARP bolts are stainless steel, do I use anti-seize or RTV or thread locker on these? If anti-seize only (which is what makes sense to me), can I use the standard Permatex #80XXX or is a nickel-based one needed?


B) Header to Ball Collector
I believe I saw some people also using Stage 8 here and not the FFR hardware? Any recommendation on bolt and thread sealant?


C) Ball Collector to Pipes
Similarly to A, I'm finding the same debate whether to use Remflex #8023 gasket, or RTV, or both, which bolts to use, and finding conflicting comments on anti-seize vs thread lockers. Some have also mentioned doing a double nut with one of them being brass to have different thermal expansion.


I know my posts are long and with many questions, but thank you to all that take the time to read and answer.

[rich grsc]

Throw away the gaskets. Use the high-temp copper colored RTV, same for the bolts going into the heads, use the bolts FFR provided for the ball flange. For the side pipe bolts, again use what FFR gave you, except use brass nuts there, in fact use brass nuts on the adjustable ball flange too.

[Jeff Kleiner]

I don't really have an overwhelming preference for gasket vs high temp silicone; I've used Percy's laminated gaskets (pretty much the same as Remflex) at the head on some and RTV on others. Same with the pipe to headers; gaskets on some, RTV on others. I haven't had a leak at head or pipe on any of the cars I've built. I am a fan of deep, coupler length, brass nuts and throw the deformed stover nuts in the trash.

So with that non-definitive answer I will say this...I suggest that you make a front hanger for the sidepipes because you can tighten the ball flange until the cows come home and over time, miles and use the weight of the pipes will still tend to allow that joint slip causing the front of the sidepipes to droop. It's basically the same issue that occurs with J-Pipes. Here are a couple of pics of the front hangers I make for J-Pipes to supplement the rear hangers. They are the same for ball flange headers & pipes. It's all just a few bucks worth of hardware store turnbuckles, nuts and bolts and a generic Mustang style double donut rubber tailpipe hanger.





Good luck,
Jeff

[rich grsc]

Jeff, good idea with the support hangers and ball flange. And the coupler length brass nuts

[AC Bill]

Can you no longer purchase the BBK headers for the 302's that FFR used to offer as an option? They were sure a lot more simple to install.

Remflex exhaust manifold gaskets work great. Are the Percy lock bolts a victim of the supply shortage plaguing us, or simply no longer in business?

[maclonchas]

Jeff,

As always you have great recommendations and opinions based upon build experience. I want to put this thread into my exhaust folder so I do not forget the parts that you suggest to replace and the modifications to the exhaust hanger system. Being more of a list guy, I like to put down all the information in one area and not hope I can find it again. Could you please be more specific on these items.

I have a Boss 347 being built up by Forte that should be ready sometime in August and the standard SS 302 Headers and side exhaust from FFR. Now let's go through each part here.

Headers Bolts to Boss 302 Block - Do not use FFR, but which header bolt do you recommend and what length?
I see you have used both RTV and gaskets for the header, but which do you recommend?
Ball Flange - Use FFR bolts but replace stover nuts with brass nuts -- size?
Hanger configuration - Can you state the parts like you did for the Kleiner Mod.

Thanks as always for your insight and help.

Bill

[CraigS]

I used rtv at the head w/o gasket. But first I spent some quality time w/ a huge flat file and palm sander to get the header flange flat. I used plain bolts but w/ small heads w/ old school lock washers w/ no antiseize. Turned out that whatever slight galvanic steel to aluminum stuff happened helped keep the bolts from loosening. That and retorqueing them 5 or 6 times in the first couple months after install. My thinking on the no gasket is this. The gasket crushes down to a certain thickness. Say it ends up at .050". When it blows out a 1/4inch wide chunk, you have a 1/4 x .050 inch hole for a leak. OTOH, RTV ends up at zero to maybe .005" (how hard did you work to make the flange flat) so it doesn't blow out a chunk but, if it does leak, it may be at that .005" spot. A much smaller leak.

[Its Bruce]

If I may...

I live in the LSx world, where I've used MLS gaskets for cylinder heads and headers with great success. Is there a reason why no one is suggesting the use of MLS gaskets for the SBF application?

[elspanishgeek]

Throw away the gaskets. Use the high-temp copper colored RTV, same for the bolts going into the heads, use the bolts FFR provided for the ball flange. For the side pipe bolts, again use what FFR gave you, except use brass nuts there, in fact use brass nuts on the adjustable ball flange too.

Thank you, Rich. Adding the brass nuts.

I don't really have an overwhelming preference for gasket vs high temp silicone; I've used Percy's laminated gaskets (pretty much the same as Remflex) at the head on some and RTV on others. Same with the pipe to headers; gaskets on some, RTV on others. I haven't had a leak at head or pipe on any of the cars I've built. I am a fan of deep, coupler length, brass nuts and throw the deformed stover nuts in the trash.

So with that non-definitive answer I will say this...I suggest that you make a front hanger for the sidepipes because you can tighten the ball flange until the cows come home and over time, miles and use the weight of the pipes will still tend to allow that joint slip causing the front of the sidepipes to droop. It's basically the same issue that occurs with J-Pipes. Here are a couple of pics of the front hangers I make for J-Pipes to supplement the rear hangers. They are the same for ball flange headers & pipes. It's all just a few bucks worth of hardware store turnbuckles, nuts and bolts and a generic Mustang style double donut rubber tailpipe hanger.

Good luck,
Jeff

Thank you, Jeff! For the first start I'll hold them with pipe strap while I make this contraption.

Can you no longer purchase the BBK headers for the 302's that FFR used to offer as an option? They were sure a lot more simple to install.

Remflex exhaust manifold gaskets work great. Are the Percy lock bolts a victim of the supply shortage plaguing us, or simply no longer in business?

I ended up going with Remflex, and I'm guessing Percy is out of business. Luckily the teardrop-shaped Stage 8 worked well so far. They are bolted but will hold off from installing the clips until a few heat cycles. I did test all clips before mounting them and I had enough clearance, so feeling good there.

[Papa]

I'll offer my experience and you can take or leave it as you wish for what works for you.

I have installed and removed headers on my car more times than I care to recall. The first install, I used copper RTV. It was great until I had to remove the headers and install a different set. I spent hours cleaning up the RTV and decided to go with gaskets from that point forward. The headers I was using were from Gas-N and I had issues with the driver's side hitting the motor mount. Georgie bent over backwards to try to get a set to fit, and I just didn't want to wait any longer with the back and forth. He even sent me a set of the FFR BBK headers to try on the car, and they actually fit pretty well, but I was already working with GPHeaders and I had custom headers made by them which fit better, but had issues with the exit on the driver's side that I just wasn't happy with. Set four I bought from FFR when they came out with the new ball flange and these work better than anything I've had on the car so far.

For bolts, I originally used Stage 8 bolts and they are a PITA to set the clips, but once they are in place, they do what they are intended to do. The difference between the tear drop and the half-moon are the distance of the bolts to the header pipes. If you have less clearance, the half-moon tabs may be a better option. I use a small amount of simple anti-seize on the stainless bolts going into my aluminum heads to prevent galling. I do the same with spark plugs.

And, after doing this so many times, one simple trick I discoverd late in the game is to remove the valve covers! You'll have very easy access to all the header bolts on both sides of the car.

Dave

[Jim1855]

In the past, for many miles, I've run the SCE copper header gaskets and have been happy with them. A fresh set is ready for this build.
https://www.summitracing.com/search/...ord=sce%204736

I've run many other types and each has their own issues, from my experience the fiber ones are my least favorite.

I've also run without gaskets using just RTV and the concerns outlined by others run with my experiences. If you can get the header flange surface flat, really flat, things should work well. But getting the surface flat takes work. I have friends that sent their headers out for Blanchard grinding and I've done similar on a large horizontal mill.

I've had more problems with the header to sidepipe gaskets and mating surfaces ultimately making my own with soft copper of about .060". Also using a square Superformance type flange with 8 holes and 5/16 hardware.

Someday I'll be running and will be able to comment on how it all works.

Jim

[Cutter 54]

I'll offer my experience and you can take or leave it as you wish for what works for you.

I spent hours cleaning up the RTV and decided to go with gaskets from that point forward.


Dave

Dave, what gaskets were you most satisfied with? You did not elaborate on this.
Any comments on bolts (grade, material) or nuts for the header to side pipe (SS, brass, steel)?

Thanks. Ed K

[Cutter 54]

Jeff,

As always you have great recommendations and opinions based upon build experience. I want to put this thread into my exhaust folder so I do not forget the parts that you suggest to replace and the modifications to the exhaust hanger system. Being more of a list guy, I like to put down all the information in one area and not hope I can find it again. Could you please be more specific on these items.

I have a Boss 347 being built up by Forte that should be ready sometime in August and the standard SS 302 Headers and side exhaust from FFR. Now let's go through each part here.

Headers Bolts to Boss 302 Block - Do not use FFR, but which header bolt do you recommend and what length?
I see you have used both RTV and gaskets for the header, but which do you recommend?
Ball Flange - Use FFR bolts but replace stover nuts with brass nuts -- size?
Hanger configuration - Can you state the parts like you did for the Kleiner Mod.

Thanks as always for your insight and help.

Bill

Hey Bill, any luck with composing a detailed list based on Jeff K's post??? Please share with others. Ed Klein

[Papa]

Dave, what gaskets were you most satisfied with? You did not elaborate on this.
Any comments on bolts (grade, material) or nuts for the header to side pipe (SS, brass, steel)?

Thanks. Ed K

I used Remflex gaskets and have not had any issues. I'm using header and side pipe hardware provided with those components and have not had any issues with those either. I have had to tighten the ball flange bolts several times and continue to deal with the pipes drooping.

[Cutter 54]

Thanks Dave. You might consider the Kleiner "anti-droop modification" posted above. I am filing his post for possible future application.

[Papa]

Thanks Dave. You might consider the Kleiner "anti-droop modification" posted above. I am filing his post for possible future application.

My issue isn't droop at the front of the pipes, but rather the end of the pipes. I don't think the hanger will help with that, but if someone says it will, I'll give that a try.