Decent header exhaust gaskets or rtv?
Decent header exhaust gaskets or rtv? Doing final assembly of my 5.3 in my 87 TA clone with a torqstorm supercharger. I got the racing innovations SS long tube headers which come with gaskets. They seem to be the thick old school graphite gaskets and I'm not trying to install and get a leak. Since I have to tune this thing myself and will be having new 02 sensors in each collector as well as my WB02 in the driver collector and I want to tune without leaks lol. Do these cheap gaskets seal well? The header flanges are thick like 3/8" and seem to be flat against the head with only 2 bolts holding them in. Since mine is superchargered I should have about 10psi and don't want to worry about blowing out a gasket etc.
So do I run the gaskets they came with? Pick up another style like dead soft aluminum or should I just rtv them right to the head? I was sick of exhaust gasket leaks and heard u could rtv the flanges to head for a perfect seal every time and did this a lot on my 521BBF and it worked great every time. PITA to get off and redo but if I don't plan on taking the headers off a lot it's a great idea and it's cheap.
What's a good not expensive gasket to use or should I just bite the bullet and use RTV?
So do I run the gaskets they came with? Pick up another style like dead soft aluminum or should I just rtv them right to the head? I was sick of exhaust gasket leaks and heard u could rtv the flanges to head for a perfect seal every time and did this a lot on my 521BBF and it worked great every time. PITA to get off and redo but if I don't plan on taking the headers off a lot it's a great idea and it's cheap.
What's a good not expensive gasket to use or should I just bite the bullet and use RTV?
Thanks, yea I won't use paper gaskets. I pulled the MLS off the motor with the original manifolds And thought about reusing them. Are the graphite style perforated core ones considered paper? I don't want one that will stick or leave residue if I go with a gasket vs rtv. My only though of NA vs FI is that FI will have a hotter exhaust charge.
How does cramping 10psi of atmosphere and a butt load of more fuel into the same cylinder space then fire a larger more powerful bang not equate out to higher exhaust temps? Specifically this reason is why Holley doesn't recommend Bosch 02 sensors in forced induction applications as they say u will be replacing them frequently. They recommend NGK bc they handle the higher heat better. Just saying... More fuel and air going in has to go out. Turbos are different as they actually hold and pressurize the headers etc going into the turbo with hot exhaust gasses so it's a ton more heat but for a different reason.
All of the headers I have installed leaked at the flange at varying degrees with stock MLS gaskets. Even the good ones like Kooks and ARH. The stock MLS gaskets are very thin and will not seal up imperfections. If the header flange is true, then they are fine.
Remflex is the way to go. One time use, but will never leak. They were the only gasket to seal my current ARH headers.
Remflex is the way to go. One time use, but will never leak. They were the only gasket to seal my current ARH headers.
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How does cramping 10psi of atmosphere and a butt load of more fuel into the same cylinder space then fire a larger more powerful bang not equate out to higher exhaust temps? Specifically this reason is why Holley doesn't recommend Bosch 02 sensors in forced induction applications as they say u will be replacing them frequently. They recommend NGK bc they handle the higher heat better. Just saying... More fuel and air going in has to go out. Turbos are different as they actually hold and pressurize the headers etc going into the turbo with hot exhaust gasses so it's a ton more heat but for a different reason.
I used graphite gaskets exclusively for a long time & will still do so.
I have ran none & RTV. That makes a mess & will burn eventualy at 1500+ EGTs on a regualr basis. I've used layered copper as well. (PITA in my diesel) Decent but more expensive & I have worn those out.
The graphited steel mesh ones would handle 1700+ EGT's for about 6-8 months or so of street driving & track use every weekend... & were cheap.
It is more important how the clamping force on the port flange is placed on the gasket than the EGT.
Last edited by gtfoxy; Jan 17, 2016 at 04:30 PM.
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All of the headers I have installed leaked at the flange at varying degrees with stock MLS gaskets. Even the good ones like Kooks and ARH. The stock MLS gaskets are very thin and will not seal up imperfections. If the header flange is true, then they are fine.
Remflex is the way to go. One time use, but will never leak. They were the only gasket to seal my current ARH headers.
Remflex is the way to go. One time use, but will never leak. They were the only gasket to seal my current ARH headers.
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I used graphite gaskets exclusively for a long time & will still do so.
I have ran none & RTV. That makes a mess & will burn eventualy at 1500+ EGTs on a regualr basis. I've used layered copper as well. (PITA in my diesel) Decent but more expensive & I have worn those out.
The graphited steel mesh ones would handle 1700+ EGT's for about 6-8 months or so of street driving & track use every weekend... & were cheap.
It is more important how the clamping force on the port flange is placed on the gasket than the EGT.
I used graphite gaskets exclusively for a long time & will still do so.
I have ran none & RTV. That makes a mess & will burn eventualy at 1500+ EGTs on a regualr basis. I've used layered copper as well. (PITA in my diesel) Decent but more expensive & I have worn those out.
The graphited steel mesh ones would handle 1700+ EGT's for about 6-8 months or so of street driving & track use every weekend... & were cheap.
It is more important how the clamping force on the port flange is placed on the gasket than the EGT.
Well the gaskets that come with the headers are aluminum Coated steel mesh graphite I believe. http://vi.raptor.ebaydesc.com/ws/eBayISAPI.dll?ViewItemDescV4&item=400579050475&cat egory=33666&pm=1&ds=0&t=1453131245141
I'm thinking i might give these a whirl, only because the flange doesn't look bad at all, the gaskets seem thick to make up any difference. Worst case is I'll have to pull it off and rtv it.
Like I said the flanges look pretty good. I bought some new header hardware, went with 12.9 12pt over cheap stainless for more clamping force so hopefully it seals up nicely.
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Well taken, Kudos.
Those look like ***. I would not run an aluminum based gasket, ever.
I ran these on my turbo 5.3 for 6 years & never had an issue... never changed them. Not even once. They were between headers I made myself for the turbo system. This was my DD & I kept EGT's down around the 1500deg (max) mark.
http://www.jegs.com/i/Mr-Gasket/720/...62#moreDetails
Ulta Seals are what I have found to work best over 20yrs of trying stuff. No sealeant, just good even torque around the port & all is good.
I checked out those Remflex's mentioned above. They look like they would be decent. Little more expensive, but worth a shot on my next turbo build.
YMMV
Those look like ***.
Graphite Coated Aluminum Core Laminate
I ran these on my turbo 5.3 for 6 years & never had an issue... never changed them. Not even once. They were between headers I made myself for the turbo system. This was my DD & I kept EGT's down around the 1500deg (max) mark.
http://www.jegs.com/i/Mr-Gasket/720/...62#moreDetails
Ulta Seals are what I have found to work best over 20yrs of trying stuff. No sealeant, just good even torque around the port & all is good.
I checked out those Remflex's mentioned above. They look like they would be decent. Little more expensive, but worth a shot on my next turbo build.
YMMV
Last edited by gtfoxy; Jan 18, 2016 at 12:21 PM.
How does cramping 10psi of atmosphere and a butt load of more fuel into the same cylinder space then fire a larger more powerful bang not equate out to higher exhaust temps? Specifically this reason is why Holley doesn't recommend Bosch 02 sensors in forced induction applications as they say u will be replacing them frequently. They recommend NGK bc they handle the higher heat better. Just saying... More fuel and air going in has to go out. Turbos are different as they actually hold and pressurize the headers etc going into the turbo with hot exhaust gasses so it's a ton more heat but for a different reason.
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I have set up turbos in the past to run low 1400's EGT on pump. There's more to the heat thing than just adding turbos to the mix. Compression ratio, cam timing, water inj., etc all have their place in where it ends up.
I'm still using the factory '98 exhaust manifold gaskets and bolts that came on my car from GM. Two different motors, 3 different sets of headers, 3 different sets of heads. One setup was a 12:1 compression nitrous motor with a 250 shot and now it's a 900rwhp twin turbo motor. Never had a single leak!
I am not FI, but have not had any problems with Mel's gaskets. I have had the problems with the header flanges themselves. I always take a large flat file and go over the entire mating surface. Low and high spots will show up for sure. Some headers were pretty bad with how uneven the surface was. If you can mount and hold it steady on a mill, I don't see why you couldn't take a few .001-.002" passes and make sure that around all primaries is flat and equal.
Thanks guys. I ended up getting a the ultra seals off ebay for like 1/2 price. When they arrive I'll try them out. Flanges look pretty flat honestly so hopefully sealing won't be an issue.
Car will be about 10psi, 160Tstat, high flow pump, HOWE 28x19 dual core radiator and I run a new Mark V 2 speed fan with controller. IATs will be controlled with snow performance stage 1 meth/water kit on a vacuum/boost switch to help keep the temps down.
Car will be about 10psi, 160Tstat, high flow pump, HOWE 28x19 dual core radiator and I run a new Mark V 2 speed fan with controller. IATs will be controlled with snow performance stage 1 meth/water kit on a vacuum/boost switch to help keep the temps down.