GR Yaris Finetuning the original for driving fun and reliability

Now after driving few miles with HJS and Wagner IC competiotion combo have noticed that less boost is better - engine pulls much smoother, and especially how engine reacts from 0-1bar boost, pickup is smooth and linear. More effortless driving which feels nice.

Sometimes less boost is more.
With or without pipes?
 
Actual implementation is allowed to take its time.
And.... all is implemented and, bit uneventful, works as expected.
- HJS cat
- IC with boost pipes
- Forge inlet duct
- JB4 with very conservative map6 and with some added top-end power.

With summer temps, car is now a joy still and now it's fun to rev it all the way out too, all the while when stress on the engine should be similar or even less than OEM. It is a bit faster instead of slower compared to the original during winter, roughly 5% lower time on 50-130km/h 3rd gear pull.

JB4 is a bit rough as a Beta but for my goals here, it already works well.

Note, these changes aren't a critique of the original car, more a general limitation of all modern turbo cars.
20220614_124354.jpg
 
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Are you still running OEM filter and the cloth panel in the air box?

Given your heat is the enemy approach would you consider a turbo jacket or Zircotek coating your DP?
 
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Are you still running OEM filter and the cloth panel in the air box?

Given your heat is the enemy approach would you consider a turbo jacket or Zircotek coating your DP?
Still OEM filter, at these power levels there is zero restriction there.
Turbo Jacket would help, bit of a pain to put in on and actually haven't seen any advertised otherwise would have gotten one when the DP was installed. DP is HJS cat and already has a heat shield.
 
And.... all is implemented and, bit uneventful, works as expected.
....
- IC with boost pipes
For clarity, I actually wanted reduced lag with the IC but felt forced to go with bigger pipes and they didn't reduce lag as I expected, more here

@Tralien
 
do you plan to change to the Kelford EZ camshaft with the stock turbo?
 
do you plan to change to the Kelford EZ camshaft with the stock turbo?
That would be fairly far outside the scope of this thread about making small improvements more or less within the original reliability/emissions window, which is 300hp/400Nm at most (GR Corolla Morizo) and unopened engine with simple breathing mods. Top end boost never seen more then 1,1bar @7k rpm (vs ~0,9 stock) so far from valve spring/camshaft territory.

For plain good old tuning though, it is a mod I would consider over a hybrid turbo, simply for reliability and some better top end breathing without compromising spool. Maybe after warranty expires and I have nothing better to do...
 
Dynos
Same day baseline, other car, with GPF back exhaust and intake MST was 267hp/367Nm

Screenshot_20220924_101159.webp

With HJS cat, Wagner IC with boost pipes and Forge inlet duct is 280hp/400Nm ('stock')

JB4 map1 and map6 almost identical, map6 made by me, basically rampup to 0,2bar boost add at 4,5k and upwards, while map1 is 0,35 add up to 5k, to no effect and worse driveability
 
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My own map6, conservative with top end (keeping back at 5,5k rpm to keep power raising to redline), should look something like the blue line
20220925_080357.webp
 
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Some updates.
- I've learned that EGT's are most probably calculated and not measured, so low EGT's may be based on false low boost readings when using a box, long term too high temps may lead to turbo failure. @DeanoC
- JB4 programmable box I use has received new firmware with GRC input, update in the jb4 thread here
 
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