CST4 Exhaust

[poe0]

Looking to upgrade my stock 2012 Speed to a CST4 and having trouble finding information online. Planning to do an intake + intercooler to support it. As far as exhaust goes, will the stock exhaust flow enough? My power goals are ~280-300 whp.

Thanks!

 

[Easter Bunny]

why are you upgrading the turbo for that power goal? you can get there on the stock turbo

 

[Enki]

Stay stock as long as possible.

 

[poe0]

K04 died. My understanding is that power goal is on the upperend of what the K04 can handle. Buddy gave me his CST4, high flow TMIC, and cobb 3.5 intake.

 

[Easter Bunny]

ok that is a different scenario than what your post seemed like

would you make more power with an upgraded exhaust? yes. is the stock exhaust going to stop you from easily hitting your goal? no.

 

[poe0]

Perfect, I'll keep the stock exhaus

Thank you!

 

[Enki]

It would be a good idea to get a flow map of that turbo; if you run the pressure too low, the boost temps could be excruciatingly high and possibly overrun the TMIC. It's the same as running too high a boost pressure or running the flow past efficiency via RPM.

 

[Easter Bunny]

Cts4 is similar to bnr s3 in flow no?

 

[Enki]

No idea, I really only know the EFRs and G series and I'd need to take another look at the maps to determine if stock boost levels are within some semblance of thermal efficiency or not.

 

[kayarepea]

CST4 is a TD05H-18G with a mazda shaped flange on the turbine inlet. Just find a flow map of that turbo and you'll be extremely close to the map for the CST4. Though IIRC corksport does actually have a flow map of it's turbo's out there somewhere, just can't recall where

 

[Phoenix]

I have cst4 with external wastagate, cpe tmic, full aftermarket exhaust, the downpipe is allegedly from ebay, it came with the car. Corksport exhuast the rest of the way. No catalytic convertor. Corksport Cams. E tuned by Justin at freektune. He estimated I am making about 315hp, I don't know a dyno anywhere near by to check or do any further tuning. My k04 started smoking so I upgraded. I probably should've got something bigger for future power but the cst4 spools quickly. Mine has the larger a/r exhaust housing, same as the cst5. Boost noises are more noticeable than stock. It was loud with just exhuast on stock turbo, with the external wastegate its much louder.

 

[Awafrican]

Cts4 is similar to bnr s3 in flow no?

yes they're fairly similar, the bnrs3 v5 is a 2867 with a .63 A/R while the cst4 has an 0.66 A/R when using the IWG