Nice Charlie,
Thanks all,
I'm relatively excited by the design, but damn I hope they work well given all the effort that's going into these.
Header Design NotesA couple key differences and the though process why I didn't just by JTR 1 7/8 (assuming I could have talked Mike into making me a set):
-All stainless steel, including flanges. Flanges came from Extreme Perfomance Sandcars (
http://stores.ebay.com/Extreme-Performance-Sandcars?_trksid=p2047675.l2563 or (909)887-8000) and are 1/2" thick but also use a design tucked quite tight to the bolt pattern. All bends came from Performance Tube Bending (
www.performancetubebending.com) which had by far the best prices I found anywhere and also happened to be relatively local; they're just up the street from Jordan Innovations.
-Big bends. 7 of the 8 primaries use 3" CLR bends coming off the headers instead of the more typical 2 or 2.5 CLR bends. The big bends in the body are 6" CLR, nested against 4" CLR. The whole thing was designed in CAD so tangencies are very good (some of the JTR joints are 5+ degrees off).
-True equal length headers looked about impossible to package without massive body cutting but I'm at least closer than other readily available options in terms of getting both the length I want and lengths as close to each other as possible. David Vizard's point that it's "more important to have lengths correct than to have lengths equal but wrong" makes a lot of sense to me.
-Merges came from Burns Stainless and ran about $400 each (more than my last headers did!). I justified the expense because Burns runs analysis software with every merge order to spit out an "optomized" header design. That was a helpful validation of the research I'd been doing. Plus it's fun with Jack Burns (legend) turns out to be this kindly grandfatherly figure who's makes googley eyes at my 3YO daughter and makes her giggle.
-Probably the biggest single debate I had was whether to run with Burns recommendation on primary sizing. I finallly did but I struggled since pipes too big is at least as bad--if not worse than--pipes too small... I was curious it anyone would spot it in the pictures but in case you didn't, these headers o' mine are
1.875 -> 2.0" stepped headers. Engine is a 429 ci but they're still massive compared to what I'm used to.
-Bonus good news. Passenger looks like it will install from below (something I was concerned about, having no real way to check that in advance). I have a few minor rubbing points but they're mightly close to fitting how I want and I think I can adjust what I have to work. Driver I haven't checked yet but I knew I'd be clearancing floorboards to keep ground clearance already so I'm less worried about that.
Anyways, that's the philosophy. Brismo7 stopped by and took a mug shot for me... Gives a better idea of scale.
What do you think? Too much or just right for a 429? I'm more or less committed at this point.
-Joel
