Lots of threads on Headers, but how about one more quick one!

[burrpenick]

It seems headers are just a pain to install on our cars, and the cheaper ones (Hedman/Dynamax/Hooker/Jegs et al) are worse since they thread thru the suspension. So, my question is: I was under the impression that fenderwells made more HP, but in reading the threads it seems like they dont? I liked the idea of possibly easier installation of this type, but worried that cutting the inner fender would weaken the chassis. COMMENTS????

 

[Leadfoot]

At the risk of saying anything dumb, I suppose if there were any benefits over the alternative, they'd be the preferred option and they'd be all over the place. There's got to be a reason that you rarely see them

 

[72bluNblu]

The fender well headers have pretty significant wheel/tire and ground clearance limitations. You end up with some pretty skinny front tires to clear the pipes. Kind of an old school drag race item.

And cutting the fender wells out definitely has chassis strength implications. It depends on how much metal you take out of course, but if you take a look at the US Cartool inner fender braces you can see they think there's a reason to strengthen that area further, not cut holes in it.

 

[cawley]

TTI or SCHUMACHER is the way to go. Schumachers have been put to the dyno test. They made more than manifolds. They are more expensive but worth it.

 

[AJ/FormS]

IMO,
you would be hard pressed to prove One "style" of header having more or less power than another. The performance of the header is mostly governed by it's length, The install, and the ability of the tuner to get all she's got out of the combo, with maybe,the number of bends in the pipes playing some small role. But even if you could, as an average and expressed as a percentage over the powerband, it would be very very tiny.

As an aside, I ran a fenderwell set in a 65 V100 with a 340.And she was a streeter. And A straight-line streeter, cuz turning it sharp was OUT! And when you park it, make sure the wheels are mostly pointing straight ahead.
I would not ever do that again,lol
But they sure looked cool!

 

[rumblefish360]

Everyone hit the nail on the head head and the posts are a GREAT testament to some of the pit falls of fender well headers.

It is very true that the style of header (pipe routing) isn't the tell tale sign of making big power, but, more on the combo and tuner of the combo.

Fender well headers we're developed due to the lack of space in cars like the early A bodies. Other examples can be seen in larger engine bay cars BUT you also have to look at the pipe diameter sizes used. While I can not explain every issue and reason of fender well headers away, they do not denote instant mega power.

TTI are full length headers and Schumacher are tri y headers of medium length which still make very good power. Ether are an excellent header for useage.

The bennifit in going to a fenderwell header is (or should be) a larger diameter primary pipe size that is to big to sanely use under chassis. Fitment issues come into play. Then when you fit them, you can not remove the starter or change plugs very ez.

 

[Leadfoot]

I was(or used to be) under the impression that equal tube lengths were thought to be part of the criteria for header design and the fender well header made this a little more feasible.

 

[AJ/FormS]

Equal length is great......If you can fit it into your chassis, and when the engine is operating in the rpm band that the headers are tuned for, ie at the race track.
On the street it all goes up in hot air, cuz the engine is rarely operating at the tuned rpm.
IMO, on the street, I see no issue with several different lengths of pipes, especially some longer ones. The longer ones tune for a slightly lower rpm while the shortest for a slightly higher rpm. So perhaps you give up a few hp at the upper rpms, where you seldom go, but gain some at the lower rpm, where your engine goes all the time. I am a very big fan of power at 30 mph, and my car is geared to be snappy right there.If I could see a header that would get me 5% more torque at 30 mph, then I could take 5% torque multiplication out of the rear gear, or 5% torque out of the cam. The performance at 30 mph would not suffer any at all, yet, there are advantages to less gear and less cam. Now 5% at 30mph, is probably not possible in a typical chassis, but you get the idea.
For a streeter,equal length is not the be-all/end-all.Getting the pipes to last more than 1 year, to me, is like a thousand times more important, especially as I get older,lol.

 

[SpeedThrills]

I built a 69 big block Dart in the 80's. It had Hooker fenderwells, I think they were the only ones available.
Yeah, they limited front tire size.
One great thing though, was the easy access to everything underneath without those damned things in the way.
In general, I remember reading that fender wells were used because you could get a nice straight tube from each cylinder before they curved, which apparently helped power.