GR Yaris HJS Downpipe with ECE-approval

I'm hoping now that the ECU has been cracked it'll tempt a few more manufacturers to bring sports cats to the market.
Not much in the way of choice currently.
We'll see.
 
Fitted mine today without a lift- right pig - in about 3.5 hours. I think spent about 2.5 hours to get the old one off and 1 hr to get the new one on. However I had some issues with the pressure tube as supplied by HJS.

How did you guys connect the HJS pressure time to the factory pressure tube? Was there a back to back barb in your box? I had to cut the end off the factory pressure pipe to make it work. I'm not impressed that I had to cannibalise the factory setup!!

FLCwSFf.jpg

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There was new hard pipe bend in the kit so not maybe need to cut original?


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You still need to cut the original. Or take another pipe with that diameter
Otherwise it‘s too short, will have too much tension on the rubber pipe and it will fall off.
Sent your feedback to HJS? And a bill for doing their work ;)
 
Got the HJS installed. initial impressions is that response and torque has been improved slightly, in addition to improvement in top end.
Engine note also little louder but not much. Referring to our dear former ice hockey coach mr. Kurt Lindström, lite bettre.

Mech said that HJS cat is clearly less restrictive (he could clearly see through it with a torch, with factory OEM it was more difficult).
The lower gasket clamp didn't align perfectly but they said it will adjust itself when driving few kms which seems to be true as it didn't leak anymore once got home.
 
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Got the HJS installed. initial impressions is that response and torque has been improved slightly, in addition to improvement in top end.
Engine note also little louder but not much. Referring to our dear former ice hockey coach mr. Kurt Lindström, lite bettre.

Mech said that HJS cat is clearly less restrictive (he could clearly see through it with a torch, with factory OEM it was more difficult).
The lower gasket clamp didn't align perfectly but they said it will adjust itself when driving few kms which seems to be true as it didn't leak anymore once got home.
As i know - the Stock Cat has 800 Cells, the HJS only 300.
 
Personally I find this to be one of the most reasonable exhaust modifications, but I haven't pulled the trigger yet.

- How involved is the install?
- Any change in exhaust note/noise-level with stock OPF-back exhaust system?

Please discuss.
You need to come for a exhaust concert to hear the difference!
 
This is one of the mods I have in mind, and was wondering if HJS has made any tweak on their package to avoid cutting the OEM one (something I do not want to do), I’ve checked their manual and this is what they say and show,

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What is the problem, that the bended metal tube they show on the image is not long enough so there is not enough engagement with the rubber hose and it ends up disconnecting and creating issues and warning lights?
 
Got the HJS installed. initial impressions is that response and torque has been improved slightly, in addition to improvement in top end.
Engine note also little louder but not much. Referring to our dear former ice hockey coach mr. Kurt Lindström, lite bettre.

Mech said that HJS cat is clearly less restrictive (he could clearly see through it with a torch, with factory OEM it was more difficult).
The lower gasket clamp didn't align perfectly but they said it will adjust itself when driving few kms which seems to be true as it didn't leak anymore once got home.
Have you had any issues with the pressure pipe as reported by some users? Thank you. It seems that providing a larger bended pipe and larger hose will resolve the issue -If I have understood it correctly- and that should be an easy fix from HJS by just adding those. Maybe what you showed on the image before is already different from the initial batches.
 
Have you had any issues with the pressure pipe as reported by some users? Thank you. It seems that providing a larger bended pipe and larger hose will resolve the issue -If I have understood it correctly- and that should be an easy fix from HJS by just adding those. Maybe what you showed on the image before is already different from the initial batches.
Have driven it so far only 50km (of which 20km were happy km's) due to Easter stuff so not good test drive though initially worked ok. Will test more tomorrow..
 
Drove 70km this morning and works fine - not sure if the resonation sound has increased (if exhaust is well fitted) but overall everything works well and car pulls nicely especially with bigger gears. Did 50-130km/h test on motorway but not record run so not worth posting..
 
Drove 70km this morning and works fine - not sure if the resonation sound has increased (if exhaust is well fitted) but overall everything works well and car pulls nicely especially with bigger gears. Did 50-130km/h test on motorway but not record run so not worth posting..
It's hard to get consistent 50-130 times... And 10-15hp is quite difficult to measure, maybe easier 150-180 in 4th...
 
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