Header Designs?

[zmoore54]

We have a 2012 Kawasaki ZX-10R engine going into a 1977 LeGrand. The car is going to be used for autocross and probably wont see anything higher than 90mph. So torque is important to us and more specifically lower end torque. We are going to have the header custom made but aren't sure about the details for stuff like primary lengths, 4-1 or 4-2-1, primary sizes, if we should have all three Ys connect to each other or have some pipe separating the two from the third? if there should be a step in there or anything like that? we also currently have supertrapp muffler and were planning on using it for at least this season (2.5" diameter) However, we do have 100db limit at 75 feet at full throttle and this is actually enforced.

Zach

[JJLudemann]

We have a 2012 Kawasaki ZX-10R engine going into a 1977 LeGrand. The car is going to be used for autocross and probably wont see anything higher than 90mph. So torque is important to us and more specifically lower end torque. We are going to have the header custom made but aren't sure about the details for stuff like primary lengths, 4-1 or 4-2-1, primary sizes, if we should have all three Ys connect to each other or have some pipe separating the two from the third? if there should be a step in there or anything like that? we also currently have supertrapp muffler and were planning on using it for at least this season (2.5" diameter) However, we do have 100db limit at 75 feet at full throttle and this is actually enforced.

Zach

I'm going to be looking into that soon myself. The obvious thing to do is to copy the stock design's primary diameter and length, the diameter and length after the 4:2, and the diameter after the 2:1. From a fluid dynamics perspective, 4:2:1 works better than 4:1 because you get reflections from two junctions instead of one, and the dual reflections can be tuned to arrive at the right times. In my case I'd like to just do dual exhausts, a single Y going to each side of the car, but my buddy who ran bikes in the IoM TT says that will be down on power and hard to tune the air/fuel ratios. Also, if you run exhausts around both sides of the engine, the second Y or crossover tube will be too far downstream. So that leaves us with a 4:2:1 header that goes to one side of the engine and splits into a dual exhaust after that. This makes one side's path longer than the other side, which in certain cases can be relevant.

-Jim

[glenn cooper]

Jake Latham has a used header from a Stohr listed in the FB 4 Sale section.
It is a right side exit and may work for your application.
I think you'd be hard pressed to find a "torque header", or someone who could promise you they could make one that produces "more torque than brand x"

[provamo]

point it straight up

[David Ferguson]

If you are serious, I have found a fellow that can design a proper header system. He will ask for significant details like cam profiles, a current dyno sheet and details on the exhaust system used to produce that. A design will cost about $500. If that works, PM me for his contact info..

[zmoore54]

This is how it turned out.

[provamo]

or should i say hoTTT..........you might want to shield that cylindrical tank

[zmoore54]

or should i say hoTTT..........you might want to shield that cylindrical tank

These pictures distort the true dimensions slightly.. we are 3 or 4 inches away from the oil tank, our major concer is how close to the airbox it is. Keep in mind, the car will only see competition use for a minute at a time. Runing for no more than 3 or 4 minutes.

[10rmotor]

What dimensions are the primaries and secondaries, and how did you come up with them? I see a step in the first primary also. I build headers similar to these, though I pair the cylinders one and two together, and three and four together. Why the different layout here?

And why the cobbled together third collector?

[AEA_Team_Lotus]

Looks very similar to the Radical SR3 design, interested how it works for you? Any intentions of putting it on a dyno?

[RobLav]

Burns Stainless algorithm derived header primary length at 13.5" with 4:1 for me for the racing ZX-10R.

[10rmotor]

Burns Stainless algorithm derived header primary length at 13.5" with 4:1 for me for the racing ZX-10R.

Have you run this setup on the dyno? Thats pretty short. I'd imagine that would be pretty peaky.

[David Ferguson]

David, If the firing order is 1-2-4-3, why would you pair 1&2 and 3&4 in a 4-2-1 design? Wouldn't the first cylinder in a pair have a different flow than the second cylinder due to the interaction with the previous exhaust stroke? If you pair 1&4 and 2&3, then the first collector see the same pulse for each cylinder (ie. 1 engine revolution from it's sibling), making it easier provide the correct air/fueling as it will be the same for each cylinder.

I think EFI tuning is challenging enough without having to account for different flow in every other cylinder.

[Jnovak]

Make sure that you read the FB rules for the exhaust height.

[JRMarchand]

Jay, the owner is not going to exceed 90mph, I don't think he needs to read the FB section on exhaust height, all of eight inches from the ground, what a great rule, do we go 8 or 6? lets do 6, no lets do 8 inches, done and done.
Good seeing you at Grattan

[JRMarchand]

I'm curious to what comments on this exhaust I had custom made for my bike engine, the work order was meant to produce a 4-2-1 "slip style" ,but lost in translation and magically a 4-1 piece is produced. I tried to talk the fabman into chopping some off and please redo into a tri-y, well that's not gonna fly, I get a 4-1 for a discounted price. Maybe the 4-2-1 will be next and keep this as a spare. I'm pretty sure it was his first time doing a bike engine header, but I also gave him a factory exhaust to study and pictures of other tri-y like rilltech's or vance hine's sidewinder stuff.
The dimensions are not top secret, 1-5/8 off the head flange, stepped twice up to a whopping 1-7/8 before the hand made collector, looks pretty, looks not like a tri-y, yes I'm a little sad that it isn't what I asked for.

[Brandon Dixon]

I'm curious to what comments on this exhaust I had custom made for my bike engine, the work order was meant to produce a 4-2-1 "slip style" ,but lost in translation and magically a 4-1 piece is produced. I tried to talk the fabman into chopping some off and please redo into a tri-y, well that's not gonna fly, I get a 4-1 for a discounted price. Maybe the 4-2-1 will be next and keep this as a spare. I'm pretty sure it was his first time doing a bike engine header, but I also gave him a factory exhaust to study and pictures of other tri-y like rilltech's or vance hine's sidewinder stuff.
The dimensions are not top secret, 1-5/8 off the head flange, stepped twice up to a whopping 1-7/8 before the hand made collector, looks pretty, looks not like a tri-y, yes I'm a little sad that it isn't what I asked for.

At first glance, it doesn't look like those primaries are all that close in length....

[JRMarchand]

Brandon, yes for sure, the lengths are way off, could that be dangerous for the engine as much as it makes the design ineffective? Cylinder 1 and 4 vary almost 100%, That can be fixed, it wont hurt to ask. Thank you

[Jnovak]

Jay, the owner is not going to exceed 90mph, I don't think he needs to read the FB section on exhaust height, all of eight inches from the ground, what a great rule, do we go 8 or 6? lets do 6, no lets do 8 inches, done and done.
Good seeing you at Grattan

The exhaust height must be between a minimum of 20cm and a maximum of 60 cm. this is equal to a min of 7.9" and a max of 23.6"

[10rmotor]

Seeing as how this guy is going to auto-x the car, I don't think he needs to follow the FB rules.

If you don't have the primary lengths at least fairly close to each other, your fueling is going to be all wrong from cylinder to cylinder. If the fab guy didn't know what he was doing, as apparently he didn't if he didn't know what a 4-2-1 exhaust was, I'd have told him to eat the cost. JR, what motor is that?

I can get my primary lengths just about equal, within a 1/4 inch without too much trouble these days. But it took me a while to get that good.

[Jasonrmbell]

10rmotor are you In the Buisness of making headers I need one

[Rick Kean]

Seeing as how this guy is going to auto-x the car, I don't think he needs to follow the FB rules.
...

JR, what motor is that?

itza Bimmer

[10rmotor]

10rmotor are you In the Buisness of making headers I need one

I don't know that I'm quite in the business of building headers, more like general fab stuff, but I do seem to be specializing in them. I've made headers for stohrs, cheetahs, A-Macs, Reynards, and zinks. Mostly suzuki powered of course, but I've made a few for R1s, and a ZX14RR in the Zink. My two oddball headers were for a turbo nitrous injected VW VR6 drag race motor out of 321 stainless, and a complete exhaust for a McLaren F1GT 3 seater with the BMW V12. Wish I had pictures of that!

I primarily make 4-2-1 stepped headers out of 304 stainless. I've got lots of customers that will vouch for my work

If you'd like, PM me your email address and we can discuss further.

[sportech]

These are out of 304 for Mike Devins. Pretty much copied the design of the bike header, including the transition between the primary and secondary collectors. I'm sure BMW spent some dyno time designing their header.

Dave
Piontek Engineering Inc.

[10rmotor]

I'm building a header for a GSXR in a cheetah, and my layout is very similar to that. The main difference is my third collector has some distance between the first two collectors. I'll post some pics later.

[JRMarchand]

Dave, I think those will fit my NovaD, call you after I sort out the problem with my fab man.

[glenn cooper]

BEEMer

[glenn cooper]

Check it.

[10rmotor]

Here are some pics. Not the one currently under construction, but its pretty close.

[Jasonrmbell]

Check it.

What car is that Glenn.

[glenn cooper]

Mine.

[Gary Slahor]

Very slick Coop.. Who did the work ?

[glenn cooper]

Some fella north of me one hour - works out of a converted chicken house.
Motorcycle guy, does a lot of high tech, precision military contract stuff.
No more info available w/o signing a release!

[Rick Kean]

BEEMer

You say potAto, ...

[Bob Wheless]

Dam Glenn that looks like welding on a nuclear reactor,,,,,,,,,,,,,, niceeeee!

[JerryH]

There are some really cool and/or strange goings on in the hills of Georgia. I once had the broken bell housing on my can-car welded up......after midnight.....by a guy a short distance from Road Atlanta......who looked like a farmer....but when you entered his very old barn, there was lots of very sofisticated welding and machine equipment. He had an inert gas welding chamber to weld the bellhousing in.....then machined it square again. He tried to refuse any payment.....saying he was glad to help......gotta love the south.

Jerry Hodges

[glenn cooper]

You say potAto, ...

Almost Kean-san, but you must remember...
"Bimmer" is car,
"Beemer" is bike!

Now that I think of it, it's a bike engine in a car...
My brain just melted down!

Jerry, I don't know for 100% certain if it's a southern thing, but I'd bet on it!

[Rick Kean]

thaza Bummer no?

[Jasonrmbell]

Sexy