It wasn't intended to you, it was intended to the original poster.

 

Then *I* took it wrong. Sorry.

RACE ON!!!

 

It probably sounded pretty bad. It's easy to take things wrong when you have strong feelings about a subject. No harm no foul.

 

You're preaching to the choir.

RACE ON!!!

 

1 5/8 for mild to wild 350 -406 is a smart move we did a test on my 406 last yaer and my 434 this year it was only worth 6 hundruds of a second that would be .06so it would look like this in the qtr
11.12 or 11.18 thats it on a pretty wild setup if you error on the big side you will give up way more than you will ever make up
if you error on the small side you will still be happy and really never give up anything worth mentioning


so pick what you want you can go with the tried and tested method or the the dyno fairy method you be the judge

 

From http://www.burnsstainless.com/TechAr...ry/theory.html

"There are many ideas about header pipe sizing. Usually the primary pipe sizing is related to exhaust valve and port size. Header pipe length is dependent on wave tuning (or lack of it). Typically, longer pipes tune for lower r.p.m. power and the shorter pipes favor high r.p.m. power."

Well we often have these discussions about diameter, how about length.....per this site, if I understand the above, length effects the rpm range of a header more than diameter....

So how long should are headers be????

 

I'm in complete agreement with Corvette Kid NC. I too value both and others opinions, also lately some of the threads have been nasty but I do hope common civility pervails. You could always wait for Darth Vader to POST again! This is my corvette internet family and friends that one day I hope to meet some of!

 

And in with the personal shots. I understand that you don't agree with my methods but you really don't have to be like that.

 

I agree from what all I have read. But most headers for street cars are compromised in this area for practical (fitment) reasons and since optimum length is so important to a certain RPM range anyway, it can only be within a practical range for a street driven or multi-purpose car. Equal length is generally a secondary concern as well in such applications so without that being very close, it doesn't matter to a great extent.

 

Sorry guys, didn't mean to start a war.
I guess I should have given a better description of the application.
Here goes, (hope I don't get kicked off the Forum or locked out for this for this)
I sold my LT 4 in November :o when I moved back to Germany. But I will soon be coming back to the States and and will be building a Lister Corvette replica (www.dragonmotorcars.com). I will be using a ZZ4 GM crate engine (355hp, 400 ft lbs tq @ 5000rpm, alu angle plug heads) and TCI Comp TH350 auto trans, mainly for fun street driving and the occasional blast down the drag strip. The exhaust components supplied with it are 1 3/4" headers. The manufacturers say this combo will produce in the 2100 lb car, 0-60 times in the around 4 seconds and 1/4 miles in 12 sec. range. I was wondering if 1 5/8" headers would be better for the street driving.
When I sold my LT 4, it was one of the saddest days in my life, but, I am really looking forward to this build and having fun driving the Dragon.

 

ZZ4 would love 1-5/8 ! Pics of the "dragon"-Cool kit car.

 

For an engine / cam that peaks at 5000 RPM you might want to consider 1 5/8 headers, but then again the kit comes with 1 3/4.... So why not tweak the engine a little bit to take advantage of them. A more aggressive cam, better heads. Bring that power band up to the 6k+ range.

 

Picture can be seen at www.dragonmotorcars.com/craigs007.html or just browse through the whole site at www.dragonmotorcars.com .
I am getting the Series II model, that has a few changes from Series I shown on the site, like "no paint" gelcoat finish(yellow), no doors, Camaro rear end (10 bolt works fine for engines under 400 hp because the car is only 2100 lbs) and it can be built considerably cheaper without the "expensive to rebuild" Corvette parts. I shouldn't have much more than $20,000 in it with all new parts. I love to work on my cars, but I have limited mechanical skills (but, my nieghbor is a super mechanic and loves to help me with my projects) and limited tools, plus after I had Optispark problems and saw what one of the Forum members was going through just to change out his heater core , I decided I needed have something a little simpler than a C 4. This is an extremely simple car, very easy to work on, much room under the clamshell type hood to get to everything and only the basic electrical systems ( a poor mans super car).
I had kicked around the idea of going to the GM Fastburn crate engine with 385 hp (its only $500 more than the $3,800 brand new ZZ4 355 hp engine) but the Dragon manufacturer assured me that in such a light car the ZZ4 engine, with over 400 ft lbs torque, would more than meet my needs ( you know, Mustangs and Ricers).
So, I guess I'll go with headers that come with the car, later I can add a Hot Cam, etc, if needed.
As usual, you guys are great. Will keep you posted on the build, but I will probably have to sit in the corner next time, you know, "Off Topic" Forum. Glad the moderators let me slip this on in, after all, the car can use C 4 drive train. And a couple have been built with LT-4 donor cars, they are real show stoppers from what the manufacturers say!

 

Man that's sweet! A nice alternative to the Cobra too. Nothing against them but there are 50 times more of them now than were ever produced. That thing has beautiful, classic sports car lines. It oughta be a blast when it's ready.

 

That's the sort of thing I'd like to build someday when I've got the money. As simple as can be, an engine, trans, differential, and 4 wheels.

I'd probably even make it simpler by putting a carb on it! Naturally though too much power is not enough so I think I'd be looking at the GM 572 cubic incher, so long as we're dreaming right?

 

Its based on a 1958 Lister a british racer that had jaguar engines, but they made a few with 327 Corvette engines and Sterling Moss kicked butt with one. Whats funny is I almost was ready to build a Cobra replica (with a SBC engine, of coarse )when I stumbled on their website. These guys are not hung up on that "period correctness" crap like alot of the Cobra guys, you know, the ones that use Lucas (Prince of Darkness) parts and those really awkward shifters. They are into building a super car that most people can afford.
Whats really funny is, I discovered a few days ago that in my hometown Villa Rica, Georgia(where I will soon be moving back to), Avanti Motors ( www.avantimotors.com )has their plant now and they are also building the Lister Corvette ( www.listercars.com for history, performance specs and pix) replias in kit, turn key minus and turn key. I think I will stick with the Dragon because of the changes they have incorporated in their cars.

 

I looked over and read a lot of their website. I almost don't see how they do it at that price. I've never seen more bang for the buck in a kit car. Very impressed with their approach and it seems to be very well thought out. I think you'll have a very fun and unique car, good luck!

 

Kid
Did you visit the Avanti site?
Under "SVO" they list their kit packages, supplied with rebuilt C 4 components, coil overs, shortened Dana 36 (3.06) C 4 rear end, everthing needed except motor & trans. I spoke with a sales rep the other day and he offered the complete kit for $17,500 or a turn key minus car (completely built car, paint and everything, except motor and trans) for $25,000. Not a bad price!! Needless to say, I am very excited about these cars!
What I like about the Dragon is they will soon be working on a removeable hardtop, that and A/C will be welcome during those brutally hot Georgia summers.

 

That sounds a lot like the problems with camshaft selection. Too many people go right to the bottom of the page. The old, "If some's good, more's better" mentality, kicks in. In the end, it's the COMBINATION of parts that make the best coordinated package.

RACE ON!!!

 

I have now. It was interesting to see that a Studebaker SUV is coming out. That oughta freak a few folks out when they see one on the road!