Thread: Let's talk exhaust housings for a bit

how long till the calum realtime gets there?

When calum isn't busy. lol.

I am 90% sure the housing is the restriction. It would work amazing on the VET cams, but the .78ar when you look at the area of the housing, the insides look way smaller than the single inside of the .63ar. The .78ar would work great on a DET motor, but VE cams don't like exhaust bp.

I need a 1.06 divided housing, or a .82 single housing to make the power I want. Not sure how much response is going to suffer, but the bigger (undivided) housings do make a lot more power. In the area of 30whp or more on lower boost pressures. The divided .78 is just choking the motor. Oh well, I will get some dyno results of my weaksauce setup and go from there. But it will require a lot more boost to make the power I would like, I just hope response doesn't suffer too much because the response on this housing is freakin insane.

IF/When I get the new housing, I will do a before/after dyno comparison to see what the gains are. I should make ~420whp on 16psi or so.

i do agree that even with the other housing your numbers are relitivly low considering the mods and the boost that you are running. when you get the realtime and a good tune to support all those mods i think thne and only then will you see the power that you should actually see. its all in the tuning, you can throw the best mods possible but if the tune isnt to par with the mods that is where you will start to see problems

I now subie guys retune for differant turbo's and they are MAF also , they dont trust an off the shelf generic tune for all the mods on there car ....I think the the more complicated it gets the harder it may be for the JWT to compansate ....

I understand where the tune is. It leaves some room on the table for sure. But 40whp? No. I'm sure the turbo would spool faster, and make maybe 15-20whp on a pump gas tune. But my timing table and fuel maps are pretty decent, though I'm not always happy with them.

The tune will automatically change timing based on airflow. If I were flowing more air, the car would make more power, but it isn't. The housing could very well be the restriction in the system with the big VE cams. Is there anyone else out there running twin scroll setup besides me and JP? I've only seen a few, but you need a larger housing or a lot of boost to make big numbers.

Tekkie, it's easy to forget Coheed lives on the moon. Not much air up there.

i use to run a GT3076R with .63 exhaust housing
swapped over to a GT3076R with .78 divided exhaust housing with matching twin scroll exhaust housing
the response is noticeable

cylinders 1 and 4 are merged together and divided from 2 and 3





but neva got to get the .78 fully tuned because i ripped of the cylinder head for a ve head conversion

i'd do a bit bigger housing if your really concerned about it, but not too big. I had a 1.14 split housing on a t3/t04e 60 trim. i'm going to a normal .63ar housing now because my mods just don't support a housing that big and be fun(stock head and cams). Man that thing would hold boost solid to 15000 rpm i bet though, much different feel then the t25 lol.

this is with it's original t3ish compressor housing. S4 RX7 turbo

Coheed now that ou are going to put the open housing use this time to make and adapter and measure backpressure it will make your life a lot easier.You need the right tools when there is no support for this motor.
I just bought the Garrett (turbo speed) gauge , egt and backpressure with this is ok to know what its happening in your turbo (setup).
regards