GR Yaris What do we think is the "sweetspot"

I'm running all the usual bolt on's and EZ cams. Dynos typically show this as about 300 wheel hp or 350-360bhp. It does feel like a sweet spot. You can pin it in any gear and the chassis can still handle all the power and torque fine. Makes the little Yaris into something that truly surprises.

The only other thing I would consider is a hybrid turbo for another easy 30hp. After this point you are spending a great deal of money for any kind of longer term reliability.
 
Similar to boosted but a slightly different path. Maximise everything this engine and turbo has to offer. Modified intake from air coming in all the way to the cylinder head. Modified exhaust from the turbo back with HJS sports cat and then remapped on the road to maximise everything that’s there. Standard cams to maintain the best possible low end torque and mapped to maximise that low to mid range hit. Before the road tune it was tuned on the dyno. Without the HJS it was 353bhp and 430 nm at 4300. I have not had it on the dyno since the road mapping but it’s a significant improvement with the HJS and remapping to suit. I would conservatively say it’s 365 and 430 plus at 3700. It’s enough, the chassis can handle it but you cannot just floor it, you need to feed the throttle in and if it’s damp you are feathering it. I really cannot emphasise how much the car changed after remapping with the HJS. I am concerned that if I went to cams or a hybrid turbo I may loose some of that low to mid range at the expense of top end. Bodywork wise the sweet spot is OEM with coilovers, real carbon mirror caps and……….and that’s it, stop there.
 
If it helps to eliminate worry, I have collected before and after data using 50-130kph 3rd gear. This is roughly 2000-6000 rpm depending on your wheel size. Before cams 5.09s, after 4.94s. This suggests that there is no loss outside the high rpm range (rev limit is now 7400)
 
That’s good to know. So no loss of mid range but more up top too. Litchfield do mine too. I think the ECU TEC has opened up more tuning possibilities. Before ECU TEC and early on they said I would low end response with cams. Good to know it’s evolved. The third remap I had done was so so much better than any that came before it. Maybe it was the individual tuner or maybe this time I did not get the standard Litchfield remap but whatever they did it bought together all the other hardware mods and transformed it.
 
GJR said:
That’s good to know. So no loss of mid range but more up top too. Litchfield do mine too. I think the ECU TEC has opened up more tuning possibilities. Before ECU TEC and early on they said I would low end response with cams. Good to know it’s evolved. The third remap I had done was so so much better than any that came before it. Maybe it was the individual tuner or maybe this time I did not get the standard Litchfield remap but whatever they did it bought together all the other hardware mods and transformed it.
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Kelford make (at least) 4 different cam profiles for the G16E. The EZ cams are the least aggressive, providing top end gain but negligible (if any) power/torque loss down lower. The more aggressive cams for making high end power do lose lower end power/torque compared to standard.
 
Still waiting on my Kelford A Cams. They should also perform ok in terms of low and midrange torque and release some power above 6k rpm.
 
I'm running around 374 with stock turbo, intake, DO88 intercooler, EZ cams, Valve springs, HJS sports cat and HKS Spec L II exhaust, tuned at litchfield.

plenty for me, mainly road car and I can still go full throttle and not feel like I'm going to kill myself, I'm reluctant to go bigger turbo as some dyno graphs I've seen the turbo doesn't spool up fully until 5k revs which personally I would hate, a decent hybrid like the GCG28R turbo I might consider but for now I've got grown up things to sort having just bought a house.
 
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AK10TOY said:
I'm running around 376 with stock turbo, intake, DO88 intercooler, EZ cams, Valve springs, HJS sports cat and HKS Spec L II exhaust, tuned at litchfield.

plenty for me, mainly road car and I can still go full throttle and not feel like I'm going to kill myself, I'm reluctant to go bigger turbo as some dyno graphs I've seen the turbo doesn't spool up fully until 5k revs which personally I would hate, a decent hybrid like the GCG28R turbo I might consider but for now I've got grown up things to sort having just bought a house.
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That sounds like a nice spec, have you had many or any cel's thrown at you 🫣
 
Stock is fine for me, I've had faster cars, tougher cars, better track day suited cars.
I guess I have started to hate the modified car scene, the idiots who want to sell their bullshit products and the idiots who buy something they can mod for their socials.
Id rather spend the money on fuel and other cars, and in my "underpowered" stock car, use more of the throttle more of the time?
 
AK10TOY said:
I'm running around 376 with stock turbo, intake, DO88 intercooler, EZ cams, Valve springs, HJS sports cat and HKS Spec L II exhaust, tuned at litchfield.

plenty for me, mainly road car and I can still go full throttle and not feel like I'm going to kill myself, I'm reluctant to go bigger turbo as some dyno graphs I've seen the turbo doesn't spool up fully until 5k revs which personally I would hate, a decent hybrid like the GCG28R turbo I might consider but for now I've got grown up things to sort having just bought a house.
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I recall in the ECUTEK thread seeing your Dyno output at 305 wheel hp. That's exactly in the range Whifbitz described as expected for all similar spec cars they have tuned (300-310 whp). Nice and strong, firmly in the sweet spot.
 
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