GR Yaris HJS Downpipe with ECE-approval

Thank you Helmut. I have an appointment with Hasler now, I'll let him install the downpipe and the intercooler. I'm curious.

The Air Intake is already ready to install.
 
If the hjs sports cat down pipe gives say 10bhp more and the gpf/opf delete pipe gives say 10bhp more.. can you run hjs down pipe with opf delete or would it throw eml lights up on the dash ..??
 
Thank you Helmut. I have an appointment with Hasler now, I'll let him install the downpipe and the intercooler. I'm curious.

The Air Intake is already ready to install.
Wagner ic? Love to see a dyno. Greetings from berlin
 
If the hjs sports cat down pipe gives say 10bhp more and the gpf/opf delete pipe gives say 10bhp more.. can you run hjs down pipe with opf delete or would it throw eml lights up on the dash ..??
I try it in this config....
 
Im a little concerned about the lag that might come with the bigger pipes. Some guys say they would install the ic without bigger pipes to have bigger cooling but not that much bigger air volume to move. You need to tell exactly before and after ;)
 
Im a little concerned about the lag that might come with the bigger pipes. Some guys say they would install the ic without bigger pipes to have bigger cooling but not that much bigger air volume to move. You need to tell exactly before and after ;)
Depends on your goals. If the goal is max power gain for track and other mainly WOT applications, then the Wagner is probably the best option if not a core that is full height (that will lag even more).

If the goal is improved response with lower IAT, maybe look for options that both flow well but have not too big internal core, tank and pipe volume. E.g. modern M-cars and AMG cars etc, nowadays turbo, use liquid cooled intercoolers to keep air volume down and response up as that is where expectations lie from previous NA models...

I'm in the latter camp and probably going for the Pumaspeed one on stock pipes with stock boost levels.

BTW, the HJS will also improve response as the turbo will spool sooner with less backpressure, while keeping everything legal/quiet.
 
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Hjs comes first...+ exhaust (opfback)....i would love to stay with wagner and not choosing another brand, so I am looking for someone that can tell the difference of using the big pipes or not. Theoretically the wagner must be little more responsive with oem pipes and a little less with its big pipes. Dont know how much lag comes from pipes and how much comes from ic itself....that needs to be sorted. I come from a Honda Integra fully tuned which was very very responsive when hitting the gas. Intake, exhaust, ecu tuned, light flyeheel, hard engine mounts ect...I need to find the best of the two worlds

Goal is to boost hp but not for peak numbers. Flat curve, decent gain, road use, no track.
 
For me, response is very important and what gives me most enjoyment and even seemingly small improvements matter. Power matters too, but on the road I also enjoy using ALL the power available as often as possible, so then current power levels, 6s in 3rd 50-130km/h, are quite good really.
 
Hjs comes first...+ exhaust (opfback)....i would love to stay with wagner and not choosing another brand, so I am looking for someone that can tell the difference of using the big pipes or not. Theoretically the wagner must be little more responsive with oem pipes and a little less with its big pipes. Dont know how much lag comes from pipes and how much comes from ic itself....that needs to be sorted. I come from a Honda Integra fully tuned which was very very responsive when hitting the gas. Intake, exhaust, ecu tuned, light flyeheel, hard engine mounts ect...I need to find the best of the two worlds

Goal is to boost hp but not for peak numbers. Flat curve, decent gain, road use, no track.
Nothing is going to beat NA for response, however have a read of this for whether longer (not wider, but the theory is the same) pipes give more or less lag.

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Sure that you wont get n/a response. I just dont want to make it worse than stock...better to not gain 10 hp than make the pedal laggy

like tuning the car with heavier rims makes it less fast...I dont want to tune the car with ic and make it more laggy....thx for the link.....
 
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Sure that you wont get n/a response. I just want to makemit worse than stock...better to not gain 10 hp that make the pedal laggy

like tuning the car with heavier rims makes it less fast...I dont want to tune the car with ic and make it more laggy....thx for the link.....
I have Eventuri intake, Pumaspeed intercooler (with std pipes as they didn't have bigger ones in stock), and HJS downpipe. I cannot notice any increase in lag, it's much nicer to drive throughout the rev range.

I don't think you can go wrong with these (just make sure the pressure pipe is installed correctly! 😑)
 
Nothing is going to beat NA for response, however have a read of this for whether longer (not wider, but the theory is the same) pipes give more or less lag.

With all respect, but that was a pretty useless article. One good point though, a good IC with long pipes beats a shit one with short pipes. But different IC designs definitely influences lag and it is something that engine engineers measure.

That a racecar with lag can win a race is besides the point, many very quick racecars have utterly terrible driveability on anything but full attack mode.

EDIT: I made a big calc but I realise this is going off topic so I moved it to a new thread: https://www.gr-zoo.com/threads/intercooler-performance-and-lag.611/
 
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On-topic: the HJS and all exhaust mods, but especially the HJS - pound for pound versus not so cheap cat back exhausts or vs the illegal/hassle/backwardness of OPF removal, reduce backpressure which helps both spool and lag. Because basically there is a bigger pressure difference between the manifold and after the turbo turbine (backpressure), meaning that the turbine will spin up earlier (spool) for a given manifold pressure, or quicker as the manifold pressure comes on (lag).
 
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I'm liking the look of this:

FB_IMG_1644133283231.webp
 
Looks like a big bore turbo back (cat delete) downpipe. Track slag?

Edit: actually looks like it has a same diameter cat on closer look.
 
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