Diy Log Manifold

[Crans]

Hey guys looking at welding up my own log manifold for my R33. I have a Hypergear ATR43G3/ATG28G4 that is internally gated.

I don't want to buy an ebay manifold, and really can't afford a 6boost type manifold.

Looking at learning to weld(I have some welding experience) and creating my own.

Found this site that sells the needed parts http://www.expressparts.com.au/manifoldmaterials.asp

Was planning to buy the rb25 exhaust flange, 4 buttweld tee's,2 90deg elbows, 1 straight pipe for all the little joins and 1 T3 Flange.

Should i be using the 1 1/4" or 1 1/2" piping?

I have a spare stock exhaust manifold to make up a jig to get the turbo sitting in the stock position. Also plan on getting a dead head to help with construction.

Just wondering if any one on here has done this before and has any helpful hints.

I also plan to hake provisions for an external gate. Any tips on placement?

[paulr33]

why try and re-invent the wheel? the stock log manifold is fine and will be ok for your turbocharger

[KiwiRS4T]

How much power are you looking for?

I have bought a Sinco Customs manifold similar to the 6Boost and looking at the work that has gone into it even though I can gas and electric weld I wouldn't even think of trying to make one.

Stocker is good for 300kw or a bit more at a pinch. No need to make provision for external w/g as you can run it off the exhaust housing of the turbo when you get around to it.

[Crans]

It's not re inventing the wheel. Its all about the tinkering and learning.

Stock manifold is good for 300rwkw my goal is around the 350rwkw mark.

[SimonR32]

As other have mentioned it would be pretty pointless, you will probably end up going backwards...

Plus you will almost surely end up spending more money and time than just buying a 6boost, but realistically... I would just stick with the stocker

PS. You can make 350rwkw with standard manifold, that turbo on the other hand might struggle

Edited January 10, 2011 by SimonR32

[R31Nismoid]

It's not re inventing the wheel. Its all about the tinkering and learning.

Stock manifold is good for 300rwkw my goal is around the 350rwkw mark.

you won't make 350rwkw with that turbo.

and that turbo won't max the stock manifold

[Crans]

Pretty sure the turbo will reach 350rwkw.Its not a high flow and the housings aren't too far of a gt35r with the .82 housing(Think thats the correct housing).

I was only considering building my own due to everyone on this forum saying the stock manifolds max out at 300rwkw.

My brother is a 1st class welder so i have the welding support if needed.

Edited January 10, 2011 by Crans

[yogibear]

i would be much more worried about the design and the way it flows more then the welds.

you could end up wasting alot of time and abit of money and make a complete useless pos car because it doesn't flow right

[Crans]

The cast HKS manifolds seam to do an OK job. Parts would only come up to $300. Was just an idea, lots of 4 cylinder cars seam to use log manifolds.

If everyone thinks its a bad idea i might just stick with the stocker for now and get a gate welded onto the housing

[urtwhistle]

I would be inclined to think that if your using but welds, I'd use the biggest I could physically get in there to make up for the poor flow you will get from using 90 deg bends.

[wasnt me]

Why is it that everyone says the stock manifolds can only flow 300rwkw???

here is a dyno sheet of my stock manifold flowing well over that. granted its a hub dyno but would still

be making 350-360rwkw on a chassis dyno

[R31Nismoid]

Cubes and a few others did back to back - just manifold.

There was like 20rwkw in it.

[wasnt me]

Cubes and a few others did back to back - just manifold.

There was like 20rwkw in it.

i wouldnt think i would be able to do that though,

my turbo has no more to give hahaha

[Adriano]

If oyu are going to have a crack at making your own manifold, why not rotate the exhaust housing, but keep the turbo in the same location. That way you will be ablt to do a proper merge collector, but will not need to change intake piping or oil/water lines.

[jangles]

The cast HKS manifolds seam to do an OK job. Parts would only come up to $300. Was just an idea, lots of 4 cylinder cars seam to use log manifolds.

If everyone thinks its a bad idea i might just stick with the stocker for now and get a gate welded onto the housing

why when it is an internally gated turbo?

[SimonR32]

Why is it that everyone says the stock manifolds can only flow 300rwkw???

here is a dyno sheet of my stock manifold flowing well over that. granted its a hub dyno but would still

be making 350-360rwkw on a chassis dyno

Jesus! Whats the settup on that? So much mid range but then falls on its ass at 5500rpm

[wasnt me]

Jesus! Whats the settup on that? So much mid range but then falls on its ass at 5500rpm

its not really falling on its ass its just the boost dropping off from 32psi down to 27psi

its a 3076 with a .82 rear

[SimonR32]

its not really falling on its ass its just the boost dropping off from 32psi down to 27psi

its a 3076 with a .82 rear

E85? That a lot of boost as well, stocker motor?

[hypergear]

Looks like 3rd gear maybe?

Make sure you clean up the inside of the manifold before using it, had seen people with ebay or back yeard manifolds fallen to bits that chipped the turbine wheel. With the current turb you will need a .70 com housing with a 58 trim comp wheel to get upto 350rwkws at about 28psi on ron 98, which I can get that modified pretty cheaply.

You will find slightly cooler EGT with bigger manifolds and external gate for about 1~2 degrees of extra timing.

[Crans]

Stao,

I though my Turbo already have the bigger compressor housing, expecially with how laggy it is. How much to get this done and how much to make a new exhaust housing with an external gate on it?