So my dad is building a '92 Civic hatch for a drag car, and he's planning on running a HUGE turbo in the bumper. Well I decided to design a custom header for him so that I could get some more experience with AutoCAD (I've been doing it for 4 years, but any experience helps) and this is my first time messing with 3D Modelling. Check it out and let me know what you think

 

New updated design and collector

 

Interesting. In the design can you do any calculations for air flow / back pressure?

 

Not on AutoCAD because its just used to build it, but I'm working on getting another program that I could do flow testing.

 

Have you read anything related to 4-2-1 headers versus 4 into 1 designs?-Bob

 

I like this design alot better

 

No I haven't, but what are the benefeits of 4-2-1 as opposed to 4-1?

Yea I got rid of that stupid double 90 bend and simplified alot of bends. It's still not perfect, but we're getting there

Hopefully when I graduate (My last year of high school :') June 2nd BTW) I can go to school for mechanical engineering and get to play with this kind of stuff a lot more. I'd really like to find someone to take me under their wing and show me the ropes, kind of like an internship.

 

Some people say that the idea behind headers is to line up the exhaust pulses
one behind the other in such a way that the pulses "pull" the exhaust out the pipe.

That's why most headers will merge four non-competing pulses into two non-competing
pulses that will merge into one pipe so that all four exhaust pulses are traveling down the
pipe on the way to the exit.

Some people say there is a formula related to engine displacement volume per cylinder
and pipe size for each cylinder.............as well as the pipe size for when two cylinders merge their
exhaust pulses behind each other. There is also a certain distance between each merging
point so that exhaust pulses don't "hit" competing pulses and slow down the flow. With cast iron
stock headers, the exhaust pulses bang into each other and that's why racers
put headers on their car.

A car engine is a wind-machine and the faster air goes through the engine, the faster
the engine runs......more horsepower.......so to speak.

The people who say that headers should have "back pressure" going back up the
pipe are usually making excuses for poorly flowing headers.

If a person is making headers for "show" instead of function, I guess all they
have to do is make them look nice.

If I have it right about the engine your headers are going onto, it looks like the exit
is going out the side of the car. Did I get that right?-Bob

 

Under pressure,
We are not talking about you and I here.
At car meets I talk with people about redesigning and "re-engineering" things.
Engineering is mostly about mathmatics.

Some observations about people.......
When smart people don't understand something, smart people will read, research,
learn, ask for clarifications and educate themselves. They get smarter.

When stupid people don't understand something, they will laugh at it, ridicule it, people-bash,
and they don't get one bit smarter. In General Car Chat and Pit Road the threads are littered
with closed threads where what I have called "brain-dead kids" have chosen to remain
stupid. Most of the time I don't even respond to them. Their words have shown what type
people they are.

There are plenty of jerks who will always try to discourage you from success at anything.
Always act to please yourself and not to please someone who wants to see you fail.
If the failures in life can discourage you from trying, the failures have won
.....and in the process have made you fail also.-Bob

It's fortunate that you posted your design here instead of where the brain-deads
could get to it.... LOL

 

What software did you use to design these headers ? Just wondering im trying to get custom made headers also.