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1974 Road Runner 400 Big Block Headers Help!


Well-Known Member
Local time
3:31 AM
Nov 24, 2022
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Cape Coral, FL
Hey guys I have been trying to inquire from other owners what is the best and easiest headers to install with the least amount of impact. Some require to drain radiators, take out head bolts remove motor mounts, etc. I have heard some owners state they have TTI headers or Doug Header and all they did was jack the car up and install from underneath no clearance issues just need to buy a mini-starter. This sounds good to me but When I look at the instructions from the companies that is far from the truth, it requires removing tons of things or modifying welding of things etc. I am contemplating keeping the HP Manifolds on it and just rust treat and high temp paint them. Anyone have any insight to assist me?
Welcome to the world of hot rodding your car. Its not like changing the oil in a new Hyundai, its work that takes time and patience and skill to make things work and fit right. stock parts bolt on easy aftermarket parts are another story. No matter who makes them. Get the best stuff you can afford and dig in . You have to do what you gotta do. its not always easy.
Part of the fun is learning how much work goes into making these cars so much fun to drive and deciding what’s in the budget for either dyi or taking a gamble on a shop. My Charger has the 400 motor from a 78 Cordoba that was purchased for that swap. The headers were a pain even with the swap involved. Headman headers fit decent in the car with a mini starter which still required dents for clearance. The collectors are snug with good ground clearance underneath.

No leaks or issues in around 7 years now but be prepared to do it right the first time and there will be minor issues. Then the smiles are always bigger when you drive around laughing.






Direct answer - factory manifolds will be way, way, way simpler for long term maintenance of the car. Headers get in the way of everything and are a PIA to install. However, I do run headers and have run several different types. If you're #1 priority is "ease of installation", then you might want to consider some "race style" headers with "slip tubes".
I have TTI headers on both my cars and they fit with NO denting for clearance but you gotta work to get them on. If you have stock cast iron heads you will have to drain the coolant below the exhaust ports.
As said, stock manifolds are much less trouble!
Good luck with whatever you decide.
Unless you've done performance modifications to your 400 or you definitely plan on them I would stick with the hp cast iron manifolds.
Hedman 78030 fit in my A body 383 with only minor tube denting on the drivers side. I bet they would be a cinch in your B body.




Yes but you have a manual box no column and I don't see a starter. So not really an apples to apples.
Yes but you have a manual box no column and I don't see a starter. So not really an apples to apples.
It’s an A body, it’s not Apple to apples at all. Y’all have way more room though.

Stock starter fits no problem, mini starter fits with a ding in one pipe. Steering column is being rebuilt, otherwise it fits right in.
Thanks for all the help guys with advice im just going to rust convert the surface rust and ceramic high heat the HP manifolds
One other think no one mentioned is… is this a factory Big block car with the engine in and running already? If not there will be a need of some trimming of the passenger inner fender as small block inner fenders and big block inner fenders are different…