What about making long tubes??? any possibility on those?

 

....just thinking outside the proverbial box here. I wonder if we could 'start' with shorty headers from a different vehicle, then make our own flanges?
I'm not thinking of the Tundra necessarily, but a more compact engine compartment like a 4.6L Mustang GT. I wonder if their Cat's are in a similar position??

 

I was thinking of the ls1 engine...

 

https://www.clublexus.com/forums/sho...eapon+r+intake

Does this header from austrailia work with usdm sc400s?
I'm sorry if this was mentioned before in this thread.

 

FINALLY...

Just heard from the fabricator. He is finally ready to begin work. He is going to build basic jigs from the GS400 manifolds to locate the head and catalyst flanges. He will then build a manifold for each side that will fit roughtly within the confines of the stock heat shielding. Once these parts are built we will find a car to test fit them on. If all goes well production can then begin.

I have contacted a member in the Phoenix area to see if he can bring his GS400 to the shop for some basic measuring. If there is any other GS400 owners in the Phoenix area please PM me.

Now, all told it is hard to say how long all this will take but this project is FINALLY starting.

 

 

These will possibly still fit the early SC400 right? And If I / I mean when I go Turbo will these still suffice? Man I been waiting to do my exhaust until these came out. Time to start saving again.

Philly

 

WERD!!!!!!

 

maybe a mod this winter after all

 

Those headers from Australia have the wrong cylinders paired up on the (U.S.)driver's side I noticed, that's what makes it such a challenge to fabricate headers for these cars. The passenger's side is relatively easy, but the driver's with the steering, pairing the front/rear cylinders, and the center cylinders, makes for a tight bundle of tubes.
Dinan had some pics on their site showing the M5 headers they make, very nice, but very complex.

 

let me know when you need a 92 SC400 as a donor vehicle.

I don't need the SC until next march or april.

dennis

 

I'm IN don't care about price or how loud i have the dual greddy evo's and i can't wait to hear them with headers

 

Any updates yet? I would be interested if the install for at least the passenger side is fairly easy.

 

Trust me, U don't want that!

I think something might go wrong if only half your motor breathes.

 

Making uneducated statements like the above serves NO positive purpose.

Consider that an engine has 8 exhaust ports. If you study the stock exhaust manifolds it is obvious that all 8 have different flowpaths / restrictions. The stock manifolds have 3 decent ports and 5 very poor ports. 3 of these poor ports are on the passenger side. If you replace just that side with a design that gives 4 good ports you now have an engine with 6 decent to good ports and 2 poor ports.

If you understand that each improved port creates both more power and less heat, blowby, valve wear and parasitic loss... it makes sense to do whatever you can.

On a stock engine you have 300hp so each cylinder makes an average of 37.5 horsepower. In truth this is not the case. The cylinders with better ports make more while the ones with poor ones make less. Here is a theoretical chart:

Piston # - power output
1 - good port 42hp
2 - good port 42hp
3 - good port 42hp
4 - poor port 35hp
5 - poor port 35hp
6 - poor port 35hp
7 - poor port 35hp
8 - poor port 35hp
Total = 301hp

After
1 - good port 42hp
2 - good port 42hp
3 - good port 42hp
4 - good port 42hp
5 - good port 42hp
6 - good port 42hp
7 - poor port 35hp
8 - poor port 35hp
Total = 322hp

Now, the above is for example only as we do not yet know what we will get... but, it should be obvious that ANY improvement is a GOOD thing.

Otherwise, you would want to restrict all ports down to the one with the worst flow... now that is something that a comment like
"Trust me, U don't want that! "
would apply.

Sorry, no updates yet, maybe soon.