Welcome chris, I’ve enjoyed watching you slay the track the last few years. I can’t help but laugh thinking how fast the pst guys are now in comparison to the top fuel bikes. All that tire and wheelbase, and y’all are within a second of those guys now on a dot tire.
I myself started to do a video very similar to the one you just posted going over the detailed info on the revisions to the new engine. Then interpreted it to what it means to me in the aftermarket world. Just like you said in the video, I’ve been telling guys on here, and on all busa fb groups that I’d bet money that the G3 will have a high percentage of hp gained vs a g2 with the same mods.
So since you made that video, I may as well cut loose All the things I noticed about the new engine. I apologize in advanced but it’s not too often I get to geek out with a fellow advanced builder and tuner. And the guys on this site really appreciate really technical stuff. So with that said...
You covered servals of the same things I was thinking. But let me toss this out there. So suzuki came out with a redesigned set of cases to improve oiling 53%. Aside from dips in oil pressure from fast 60ft’s, and lack of oil returning back to the oil pan on land speed bikes, I’ve never considered the oil system on the other generations to be a weak point. Speaking from my automotive side of experience (mostly LS, SR, and 4G63 stuff) typically you don’t see excessive oil system mods unless the engine is going to turn unusually high rpm... hmm
So, major oiling improvements, and then the crank, pistons and rods have all been lightened up as well. We know that a lighter rotating assembly will spin up faster/be more responsive. Yes a, lighter rotational mass won’t wear bearings out as fast. But all that also lends its self to being able to rev higher as well. (I swear I’m going somewhere with this lol)
Im really interested in the new exhaust camshaft. It has more lift, and both cams have been retimed to reduce valve overlap. I’m excited to mess with that cam in boosted applications as when you look at aftermarket or customs cams designed for turbo applications you’ll typically see they generally have more lift and not as much duration as you’d see in a NA or nitrous combo. I’m willing to bet those cams will be worth their weight in gold in a few years on psychobike when guys start wrecking and parting out G3’s. As far as the new cam timing “that has been updated to reduce valve overlap and boost low to mid rpm range engine performance” I think we can revert back to previous generations to see what this means, and how it affects the G3’s hp numbers.
So suzuki constantly brings up the low-mid rpm improvements with the G3. Looking at the dyno graph suzuki posted you can clearly see it has a much broader torque curve, but peak HP happens sooner in the rpm range, and falls off faster then the other generations. This interests me very much as I’m betting simply re degreeing the camshafts on the G3 is where we’re likely going to find a big power gain.
For example on the previous generations you can replicate that same dyno chart by advancing the exhaust cam and either leaving the intake cam alone, or retarding it a few degrees. (Referred to as spreading the centers) That will decrease valve overlap. When you do that, you’ll see the engine produce a much broader tq, and hp curve, but with the sacrifice of overall peak power. Definitely going to be some big gains there I would think.
And for what it’s worth I’ll add this in. From tuning cars through their factory ecus that have variable cam timing you’ll notice that they’ll “spread the centers” sometimes for fuel economy, but mainly do it for emissions reasons. See what suzuki did there?
Lastly, the improvement I’m most excited for is the new cylinder heads combustion chambers.
pic from suzuki Australia:
The “updated twin swirl combustion chambers” is basically something called un-shrouding the intake valves. Reworking the chambers like this is common practice in the LS, and Leads to 5-10hp gains just by doing that. Doing that allows for the fuel/air mixture to stay conical as it flows over the back of the intake valves and reduces the turbulence created when the mixture bounces off the cylinder wall. This helps keep the fuel atomized and a more complete burn is the result of that. But if you look a little harder you’ll notice some other changes. There’s more chamber work done to the area between both the intake and exhaust valves. It may not be so obvious in that pic, but the area around the spark plug is recessed in to the head more as well. It will be neat to see the gains from the chamber improvements in conjunction with addressing cam timing, exhaust, tune etc.
But now look at a pic of the actual head vs the G2, and you’ll see the chambers are vastly different.
You can see the chambers on the new head have a much more pronounced spherical shape to them. Does Doge Hemi come to mind? The new head should really shine in nitrous/boosted applications.
The G3 has the same 12.5:1 compression ratio. We know the bore and stroke are the same between the G2 and G3. But assuming the cylinder deck height is the same as the G2, the compression ratio would be a lot lower with the g3 head, on less the pistons are different. And they are. Any time you remove material in the combustion chambers you’re effective making them bigger. (More volume) the only way to get compression back up is to have a taller piston, or one with a smaller dish. You can see the difference between the two here. On the sides of the piston that run in lone with the wrist pin, you’ll notice the areas that are more pronounced in comparison to the G2.
If I’m correct in my observations then that would mean the chambers are bigger. In boosted applications the bigger the chambers, the more air that can squeeze in, which means more fuel can be added which means greater power potential. This engine is gonna love boost... I think.
Again Chris, sorry to write a book here, but I geek out of this stuff. I’d love to hear your thoughts on my speculations and maybe add to them. And my explanations here were intended for the members as I’ve found over the years they eat up real technical stuff. They’re not intended as me trying to big bobo you, or anything of that nature.
My pipe dream assessment of the G3 engine is this. With all the lighter, stronger internals that more suited for a higher revving engine, cams that just so happen to be very well suited for turbos, and larger, more efficient combustion chambers, lead me to think maybe. Just maybe is suzuki setting the stage with this generation for a factory turbo model? Again, that’s a pipe dream that I generated since studying this new engine.