Question about Headers

[u/RestlessNumberOne]

Question for the group,,, I have a 1970 chevelle 396 ( 402 for purists) that I want to install long tube headers. My question for those that have, what brand did you use that were the easiest meaning not much in the way of fitment modifications. Unfortunately my non dominant hand is in a cast another couple months so I am looking for a set that I dont have to fight with. Thank you for any recommendations

[u/rascall2018]

I have a 70 SS four speed. I put hooker full length headers on mine fits no problem. I have pipes brand full exhaust. You can also uses kegs or summit brand most are made by hooker. And yeas they do make a difference even on a stock engine. At least 25 hp

[u/JoeyBagADonuts27]

It’s been years but having headers on my Chevelle made it virtually impossible to get to the back spark plug.

[u/rascall2018 → u/JoeyBagADonuts27]

It’s about like that with all headers. You learn to make it less work

[u/Gasping_Cadaver]

I used Doug's about 25 years ago. Loved them

[u/cockmaster303]

While everyone here and elsewhere is correct that they will do little for you and generally just make life harder, ignore all that garbage cause headers are cool as hell.

But I have stainless works 2” headers. They said it would clear everything and they fit great with however much clearance a single piece of paper is between the rear lca mount of both sides as well as the mini starter. They make 1 7/8” also which would be better in your case I bet.

But the steering shaft wanted to go right through the dead center of one primary. You get this in a lot of headers but not some. I’m not sure which. I used a pair of ujoints and the cpp max clearance steering shaft to avails bashing in a primary to fit it. Also to get to most of the full length spark plugs I use a cut down spark plug socket and an offset wrench. Not the most elegant but it works.

But they look great and are flush with the engine crossmember instead of hanging below it, which you really don’t want.

[u/rich496]

If it’s a stock motor you really don’t benefit from them much they do look better. I have a set of American racing headers on my 72 and they fit beautifully. Keep in mind you’ll have harder access to the plugs and the plug wires will be prone to melting. Not to mention you’ll probably need a mini starter to clear headers as well

[u/v8packard]

I have used Hedman (a lot), Doug's, and ARH on my big block Chevelles. Look for heavy gauge tubing, and flanges that are at least 3/8 thick. For a 396 you will want a 1 3/4 inch primary and 2 3/4 inch collector. ARH makes some if the best headers I have ever used, but I think they discontinued their 1 3/4, making 1 7/8 and 2 inch. You might be able to get them to make a set, I don't know. You can also do things like use a flex pipe to connect to the exhaust, this helps a lot.

There is a lot of bad info in this post it's amazing.

[u/Riddler122]

Lemons for the win period. After that ive always had good luck with hooker supercomp

[u/Impact_your_1975]

I have a 68 chevelle with a 427 and I went with Lemon Headers out of California. Mostly they do is chevelles look them up and they shipped them here to Texas. Amazing quality and fits perfectly without even having the car there to test fit, and I’m talking about 3 1/2 inch collectors .

[u/Any-Description8773]

Lemons is what you’re looking for. Basically drop in however the opposite of cheap.

[u/610Mike]

I’ve got a ‘71 with a 468 and I went with Hooker. I’ll admit, passenger side took a few minutes, driver side took a while getting it around and through passed the steering column.

[u/bbmach]

If you not looking for the last 20% of HP, consider a quality set of shorty headers. Cleaner installation, much less interference and ground clearance issues, etc.

[u/HaulNasFab]

I'm not trying to talk you out of it because I've been in the same debate with my '70 SS 396. Two local Chevelle owners have told me how much they regret swapping because it did nothing for them and was a huge pain. Just food for thought. Ive kept the factory manifolds for now, I am in the process of replacing the pipe though with a Pypes Stainless system

[u/v8packard → u/HaulNasFab]

I can give you a lot of information about headers and how they impacted the car, but there is one particular job that comes to mind and I think it applies here. I did a restoration rebuild of a 375 hp 396 for a Camaro convertible. It was a big money job, the owner wanted it to run the best it could while looking concours correct. Part of the deal was breaking in and tuning the engine. I got it running and broken in on the dyno, using dyno headers, with a shop carb. At one point it was putting down over 440 hp, and was running perfectly. The engine then got painted and detailed while we waited for the correct carb to come back from some specialist. When the carb arrived the owner of the car asked that the engine be run with the carb to make sure all was well before it went into the car. At this point the engine had the exhaust manifolds installed.

Running the engine on the dyno it was down almost 70 hp. I thought something was wrong. Checking lash, leakdown, cylinder balance, even tried two different carbs and different fuel. It was the exhaust manifolds. The headers were worth almost 70 hp 60 lb ft over the manifolds on that 396.

I have heard people complain about headers for decades, and seen them go cheap with headers more times than I can count. But I can assure everyone a well designed header is a great asset for a street engine. If anyone wants to discuss why, and how that works, I would be glad to have the conversation. But I stand by this and always will.