swap headers design, please help!!

[ka-t4u]

hey everyone, exactly what the topic states is the matter at hand here, i am ready to perform a vh45 swap on my s13, i already have the engine and transmission, also the ecu and wiring harness, now it's all down to cleaning stuff up and getting conversion kits and such, now we are all well aware of mazworx headers which are obviously a high quality product and it has been proven to work, but the price tag doesn't really fit me, lol i dont think it fits many of us, so given that i am in a tight budget and i take a lot of pride into what i make, i would like to make my own headers using one of those kits from jegs, i can weld, not too pretty but i can practice, my one and only concern is the design of the things, anything special i need to worry about?? or just make them as close as possible to the engine?? so they pretty much "hug" the engine and transmission?? or do i need to make a runner curve out and form a loop to run the steering column thru?? any help is greatly appreciated!! i should also add that these will be the first set of headers i make!! lol

[flyingbrick]

hey dude.

From personal experience I can say this.

After buying the pipe, flanges, equipment and supplies you wont be saving as much as you think.

It will be harder than you think.

You will give up and wish you had bought finished headers in the first place.

Headers are not a good first welding project.

All In my opinion.

-Nathan

[EMK]

Please don't find yourself discouraged by the previous post simply take it as a notice that there are some who would much rather not do the custom fab work it takes to build a set of headers. It takes some serious time and effort to do this not to mention BALLS!!!

But let me clear a few things up.... you won't save money by doing it this way??....
You'll need flanges and some other things if you don't already have them but $800 vs. this

http://www.jegs.com/p/JEGS/JEGS-Header- ... 5/10002/-1

Welding isn't so easy a caveman could do it but it it fairly easy to do with steel as long as you don't burn all the way through what you're welding you can always go back and fix it. Penetration is good and on some things essential but on exhaust that you want to hold a seal and not crack it's not gonna ruin it if you're not right on the edge of burn through. If you're using a MIG welder and are following the recommended settings you should be great.

As for design.... that's the best part of fabrication... its up to you. If you don't like it rip it apart and do it differently. That is honestly the best part about doing custom fabrication is that if something doesn't work with this or later on in the future you have the skills and tools to go and fix it instead of pick up the phone and whine to the people who sold you something that's not working the way you want it to. So think of this project in a way as an investment the return being the money you save in the future from the lessons and skills you learn in the swap.

Welcome to the family of VH swaps whether they be finished or in progress (ME)
Do it how you want because at the end of the day it's your money and time and effort

[ka-t4u]

Thank u guys for your input, discouraged.....am not am all in for it, I really want to do it, like I said my worries its the fit inside the car, in order for them to fit in the car, do I just makethem fit as close as possible to the engine???I will be fabricating them on the engine stand that's why I'm so concerned about the design....and for flanges I'll just cut off the ones from the stock manifolds.....

[klh6686]

I agree with both of the first two responses, If you are confident in your ability and have the means to properly perform all the cutting and welding required for headers as well as dealing with space constraints, go for it! Just make sure you understand what you are getting into and the fact that most people get in over their heads with a project such as headers. Let us know what you decide to do!

[EMK]

I didn't know you meant engine on stand. Best advice for something like that is to try to look at a build thread of someone who's done it te way you want it and see the route they took. Everything could change whether they fit or not depending on the chassis or the mounting position and even the accessories you use.

Although I do believe most everyone has tucked the primaries together before the steering shaft.

Look at the threads by gsracer and crazytrance they show a pretty thorough writeup of their headers

[ka-t4u]

yea am gonna be making them on the stand am just gonna go for making them fit as tight as possible to the engine block, thanks for the advice i'll look for those threads!!

[scir16v]

If you are going to build them on a stand, you might want to bolt the engine crossmember in place. It will help you gauge where the pipes need to run.

[ka-t4u]

awesome idea!!! i'll just wait till an s13 shows up at the local u-pull and snatch a crossmember with a rack!!!

[flyingbrick]

I agree! great idea

Get the thickest head flanges possible- 12-14mm thick as this will reduce the amount things distort during welding.

You will need to get the flanges machined flat once you have finished, so budget for this too.

[jalinar450]

Make sure you allow room for the big a$$ 300zx starter , I already made that mistake lol

[DRFTBLD]

not sure if you have finishe4d these already but I would build them in the car for the most part if you can. It is easier to get the right path the first time round IMO.

[brainfood]

What size primaries is everyone using? 1 5/8"?

[DRFTBLD]

1 3/4inch/ Fits perfectly inside the opening of the Mazworx flange. These engines need to breath too so the additional size is good.

[EMK]

1 5/8" is the stock size. I believe gsracer did his both ways and has dynos of both the engine with stock size and then with mazworx headers. I don't believe there was any difference in power.

[DRFTBLD]

The stock size is 1 5/8 but if you use the mazworx flanges you will need to use the 1 3/4 size to fit in the opening the best. the 1 5/8 just doesn't fit right and you will have a lot of space to weld/fill.