GR Corolla vs GR Yaris Exhaust Valve Spring Rates 

I guess anything about gearboxes, cables, linkages, internals. Maybe flywheel? Does it also have this funky two mass flywheel withiut springs?

And my biggest concern is how to get a throttle response adjuster like facelifted GRY has , but guess it's a future question.

I like your thinking. Will look into it and see if we can report back on any findings.

​@@romka_ind there is already aftermarket throttle response tuner its called pedal box there are others

Thanks for the heads up @tonyw2960. Have you had a chance to try it?

That's an interesting idea and would make a cool deep dive if we did a full metallurgy comparison of the alloys. When we last did our research, it was rumoured the pistons were forged and a stronger alloy was used for the GRC. Do you know of any more recent information that has come out? Referring to our short we made here: ru-vid.comS87hXoSNhWg?feature=share

Yep! A winning combo - Kelfords and a set of our rocker retainers. 👌

Do you have upgraded springs and retainers?

We don't make upgraded springs and retainers ourselves but we're an official distributor of our friends across the ditch that you mentioned 👍 Looking to upgrade yours?

Just clarifying we don't make valve springs and valve spring retainers but we do make rocker retainers: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-V4IDYBl5LaE.html

Do you mean all of the engine differences?

Yes! @@denstoj

A few people in the comments are keen to see further videos so we'll look into it for sure. If you haven't seen it yet, our short video does talk about the rumoured differences when the GR Corolla came out: ru-vid.comS87hXoSNhWg?feature=share

Thank you! I'm glad you found the video informative. A little different diving into the equations/educational part. Yes, making a generalisation, stiffer valve springs mean an engine can achieve higher RPM without suffering from valve float, but it's a bit more complex than that because the valve is slightly heavier too on the GR Corolla.

Thanks! Just clarifying you mean running GR Corolla exhaust springs in a GR Yaris?

You caught me! The whiteboard is a dead giveaway. @EngineeringExplained

Appreciate that! 👊 Check out the video on the end screen, Daniel shows a part number break down of what’s different in the head including intake valve springs. Hint: They’re the same. 😉

Good question. They're new. We opened them up in our previous video where we unboxed everything and compared the rest of the different parts in the head: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Dfj-3-q7BSI.html

@denstoj Then it is a proper test, good job. Could it be that GRC springs are stiffer cause GRC valve is also heavier, which basically equalises the difference in springs?

Thanks. Yes, great pickup. You're on the money. After recording the video we realised that would have been good to mention but I'll do it here instead - As shown in our previous video, the GRC exhaust valve is 2.35 grams heavier than the GR Yaris at 45.24 grams. This ~5% increase in weight offsets our measured ~3% increase in stiffness. The video I'm referring to where we show the valve weights is here (if you haven't seen it): ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Dfj-3-q7BSI.html

@denstoj I think I watched all of your GRY vids today. Your channel deserves much more attention! Great job!

Thank you! Will keep it up. Please feel free to share with anyone you think would find the information helpful.

Sure thing. It will be more difficult to measure but we'll do our best to capture any differences. Might throw in a Kelford spring too and do another little video. 👍

Thank you 🙏

No worries, planning to measure it up next week

Any updates?

Apologies, will get back onto the engine shop to borrow their spring tester and report back

Yep, sure does. Lucky it’s got extra hp 😎

​@denstoj same soon with the mk2 gr yaris.

Got yourself in the lottery for one? 😎

@denstoj I live in Australia and my cousin works for Toyota. Haven't really thought about getting one. Thinking of buying a gr supra.

Very nice. Can’t go wrong with the picks from Toyota at the moment!