Recommended headers for sbc in my '72
 

I put a set of Flo-Tech headers on my truck years ago. The gaskets have failed (for about the 10th time) and I need to replace them. It has always been a nightmare to replace the spark plugs on the right side. I would like to know if there are any headers that have enough clearance to be able to remove/install the spark plugs? Any recommendations? Thanks!

Re: Recommended headers for sbc in my '72
 

Whether you replace them with a new set or reseal the existing ones them you really need to make sure the gasket mating surfaces are completely flat and in plane across the all four ports. Just hitting them with a file won't do it. Ideally you would want to use a belt sander large enough to sand all 4 ports simultaneously thus ensuring they are all true to each other. (Photo #1)

If you don't have access to such a sander then gluing some 60 grit sandpaper (You can start with 36 if the surfaces look really bad) to a flat sturdy bench and holding the header mating surface perfectly flat while moving it back and forth is the next best option. After doing an initial sanding If you find a seriously high spot you can knock it down some with a hand file. Then do another round of sanding. The idea is to get a perfectly flat surface across all four ports.

Slowly work your way until all four ports are flat with a minimum of 1/8 of sealing surface. In a perfect world all the sealing surfaces would be the same width across around every port. That way you would get equal crush pressure all the way around the port.

There is no way that just tightening the bolts down will achieve equal pressure around every port unless the surfaces are fairly equal in width and true to each other.


As far as spark plug clearance it isn't a problem to dimple the header tube so a socket can pass by. Photo #2 shows how my PO dimpled mine using the BFH method as opposed to the heating with a welding torch and massaging the clearance with a socket or short piece of pipe.

Unfortunately buying new headers doesn't guarantee the mating surfaces are flat and true across the entire four ports. The same is true for spark plug socket clearance. I actually prefer using used headers as they have taken a set from all the heat cycles over time and usually are more stable.

Taking the time to do these steps will give you much longer gasket life. I've had headers on daily drivers for decades getting 30k plus miles on gaskets. Doing a quick check of the bolt tightness every oil change will help keep those headers sealed.

https://www.mcmaster.com/products/ad.../grit~60-grit/

Re: Recommended headers for sbc in my '72
 

I have an alternative recommendation. When I put in my new L31, I ditched my headers and went with 2 1/2" rams horn manifolds. They flow just as well, and I don't have all the headaches that come with headers.

Re: Recommended headers for sbc in my '72
 

OP, while you do want header flange flat, sometimes they are not dead nuts. Remflex gaskets are quite thick and work well for headers that are not perfect flat. Obviously, there are limits but try a set. They also note retightening is not needed.

For plugs make a slotted socket out of a donor plug socket. Also using open end wrench can access tight to tube headers.

cut some off the wrench end and remove 1/5 of the side so the socket comes in sideways, then down towards head. Use box wrench on the socket to loosen plug. Remove socket and take out plug by hand

Re: Recommended headers for sbc in my '72
 

I put these on my ‘70 C10 with a 350.
Fit perfect with a great finish.
Zero problems changing plugs.

I used the gaskets with thin layer of copper gasket maker.
Been on 5 years now with no issues.

https://www.summitracing.com/parts/s...ckup/year/1972

Re: Recommended headers for sbc in my '72
 

I’m not a header guy, but I know good customized tooling when I see it. Sweet!

Re: Recommended headers for sbc in my '72
 

Agree.... cast iron on my Big Block... under hood heat is also reduced.

Re: Recommended headers for sbc in my '72
 

Have you tried the thicker gaskets that will compress to take up uneven surface conditions. I had sealing issues with a cheap set of summit headers to a cheap set of Edelbrock heads because there was a pretty close edge of the header opening to the port. This gasket fixed my problem. Remflex 2007 D-Shaped Port Exhaust Header Gasket This is a D port cut but they make other configs to match your head. Also, be sure to match header and head port shape or you will struggle to keep things sealed. Quick free shipping on Amazon for this product.

Re: Recommended headers for sbc in my '72
 

I have no experience doing this, but a friend told me he used to cut the flanges between cylinders 1 & 3 and then 5 & 7 on the drivers side....2 &4 and then 6 & 8 on the passengers side. This allows the flanges to be tightened down individually for each cylinder except for 3/5 and 4/6.

Re: Recommended headers for sbc in my '72
 

Well, I replaced the header gaskets, valve cover gaskets, and spark plugs over the last couple of days. NOT a job for an old man like me! The next time, I will probably change back to "Ram's Horn" exhaust manifolds. The removal of the A/C compressor and the fact that the header bolts were difficult to line back up was ridiculous. I just need to finish up the driver side (the "easy" side) today. Hopefully she'll run a little better, now. Without oil leaks.

Re: Recommended headers for sbc in my '72
 

Exactly! Here's a link to the Remflex gaskets... https://www.summitracing.com/parts/rfl-2006

Re: Recommended headers for sbc in my '72
 

+1 on the Remflex gasket. Fixed my issue with some cheapo summit headers.

Re: Recommended headers for sbc in my '72
 

Same for me!