1JZ VVTI vs NON VVTI flow battle! 

The vvti head has smaller ports because thay wanted drive ability at low speed and variable timing makes up for power losses up high , it's a compromise, out right the vvti head would be the best for after mods and power, looking Luke a large port opening would change things dramatically I think. 😊

You are the first person to do this comparison! Thank you! I wouldn't put much effort into the non vvti head because they aren't even making them anymore! If you want a new 1jz cylinder head, you have to go with vvti.

I would like to see you do something with a 12v vr6

I get that people love the sound of the 1JZ but from a purely bang for your buck value standpoint, you can get a late model VVTI 2JZ-GE for $1500-1900 whereas the 1JZ is around $4000 and can’t make the power of a 2J. You’re already putting forged internals in a 1.5JZ that has less port flow than a 2JZ-GE. It all makes no sense to me, but I’m just a Nissan guy so what do I know.

Great comparison.. thanks for share information ❤❤❤ like

the real question will be once ported with bigger valves, how's the flow and velocity.

1.5 J that's what I got make an over a thousand horsepower me personally do not like the vvti head the cam gears make a lot of noise I can see and understand his flow test but but I don't know for some reason 1.5 J non vvti makes a lot of power and this is stock head with valve spring and retainer 264 cams

Great video. Thanks for the knowledge. Could you please do a comparison test with the sr20det from s13 and s14/s15, both the na and turbo versions.

This is an awesome video! I think 2JZ-GE VVTi vs 2JZ GTE VVTi head flowing and port design comparison would be fantastic. Even GE non-vvti vs GTE non-vvti

Circle

With the exhaust manifold is another reaction with the back pressure? I have a teacher that tries 5 different exhaust manifolds on natural aspirations and the expensive one gives less hp because it maybe for not ported but the cheapest from eBay was in most horse power gain the other 4 was custom made work better or similar to the expensive.

Can you please test to see what the combustion chamber cc difference is ? They must be different as I’m reading the non vvti 1jz has 8.5:1 comp vs 9.0:1 comp on the vvti 1jz

🇦🇬 ⭐️⭐️⭐️⭐️⭐️. 🙇🏾‍♂️

I'm building a non-vvti1jz at the moment, and as I already have all the manifolds and ancillary staff, I don't want to change that - so I would be very interested in seeing how the exhaust ports could be modified to flow better. However, as I'm going to be using this as a road car, I don't want to lose any bottom end power. Would increasing the flow on the exhaust ports have a detrimental effect on low-end torque?

not sure if i saw correct but the up coming video you are doing with the stock vs oversized valves on the 1jz, you are leaving the ports stock with just an oversize valve? no pocket port

what work is needed to make a 1j flow as much as a stock 2j also, can we see the benefits of a back cut over stock? or show us 6 different levels of work..make every chamber a little better than the one next to it-from stock too all-out (and everything in between)

I want to know how does both of those heads being ported compared to each other?

I assume the TOYOTA UZ V8 VVTI heads flow better over the non VVTI.

what if rb 26 valves were used in a 1jz?