HEADER
What my goal is here is to make a header that is a direct replacement for the original front exhaust manifold. Thats all I'm going for here. Why just a front header? The main influence is Franz knocking about .3 seconds off his 1/4 mile with the headers he has made. Check out my links section for a link to his sites. Headers have also been dynoed on many different applications for proven performance gains over and over as well. Plus if it's a direct replacement then the odds of more people wanting to buy one are higher. More buyers in a market makes for more suppliers. In this case one supplier would be nice since there are none.
Will this give any noticable gains? On a Z26, yeah, I think it will very nicely if you were to put it on along with the new style rear manifold off of the 3400. I first saw this here at ZZracing.com.
If you go to my exhaust mod section on this website you will see a picture of what the rear manifold looks like on a Z26. I'm the furthest thing from an expert, but just a glance at both of those and it looks like a safe bet that the 3400 manifold will flow better. I know it will bolt up to the head. I dont know if it will bolt in with the rest of the 3100 exhaust system. You would think it would, but I'm not sure yet. Heres the 3100 exhaust manifold in a similar position:
It looks like the crossover pipe should bolt up the same but the obvious difference is where it bolts up to the down pipe. I'm sure you could make it work though, and a junk yard would probably be very willing to hack off the downpipe from a grand am for about $30 or so.
So how am I going to make the header? Well, all I have to show so far is this:
This is the flange that will bolt up to the cylincer head. All the holes line up nearly flawlessly with the exhaust manifold gasket, which is what this was made to. It's 5mm thick steal, very strong stuff. Once the header was made, this flange would have to be cut into three individual pieces to fit properly onto the normal exhaust manifold gasket.
The next thing after getting the flange perfect is to make a fixture that the original exhaust manifold bolts up to perfectly. This shouldn't be too big of a job. I just have to have one more peice special cut for the outlet on the manifold. Then bolt them onto the manifold and then use some strong scrap to weld the two peices together. Presto, I have a fixture to make the header to.
Then I have to bend the tubes, after I find some tube to bend. A collector is next. Easier said than done. I personally think these two steps are going to be the hardest, for me anyways. I don't even know if I'll make it this far. Either way, I'd like to get atleast the fixture made and the tubes bent. I'll be using the following 5 Design Specs to make the header to.
Design specs 1 Design specs 2 Design specs 3
(These were taken from http://www.gmpowertalk.com/ )
If I get one made and the results of track testing are good then I would be very willing to send the fixture along with the header to a manufacturer for full production. I would like to test it out on a bone stock Z26 too along with mine. Odds are getting this manufactured wouldn't be too hard since it looks like it would have a wide application if it also bolts into the 3400 exhaust system, not to mention the new 3100 exhaust system. That would be a good majority of GM's FWD cars. And with the attention the newer Grand Am's are getting from the aftermarket scene I think the outlook would be good. ... I'm getting way ahead of myself.
