Why do 1UZ heads suck soo bad, what can we do.

[4000GT]

http://www.youtube.com/watch?v=-HwSZSdCczI

Here is me

 

[SuperRunner]

Not side by side, but on the same bench. Numbers won't be much different if I had done it side by side.

That is at 28" with a nice radius port.

 

[ed_ma61]

.100 92.3
.200 155.5
.300 199.1
.350 206.7
.400 214.3

yup, corresponds almost exactly with my data on a stock uz head (within 1-2%) perhaps you should be checking your data john dont let me pull out the vvti ported figures now eh?

 

[4000GT]

Ed, what did yours do ported? We maxed out 260 on the inlet side with stock valves, going larger now though...

 

[ed_ma61]

got up around 285 @ .500 28" h20

 

[ed_ma61]

and i should say too, thats not a hogged out port. its an NA port, and i wanted to keep the velocities up a bit, so peak numbers might not reflect what the port "can" flow outright, just what mine did and furthermore, at 11,000rpm and about 530bhp there was no indication that the ports were chocking

 

[Arnout]

Stock Cam timing 1UZ-FE

Sorry wrong post

 

[djr48312]

I know this has been somewhat discussed before, but I wanted to know if there has been any progress on getting better flow, and what needs to be done to achieve this. So that is what this thread is for:

After doing a little research on the 1UZ head, it seems to me that this is the biggest problem about the 1UZ engine. I have been working a bit lately with the 2JZ heads, and they flow way better than the 1UZ

Stock 2JZ heads get about 90cfm at .10" of lift, and 180cfm at .30" of lift, where as the 1UZ only gets 51cfm/120cfm respectivly.

With some mild port work, is there any way to get even close to these numbers? I have a ported 2JZ head that I have been able to get 210cfm at .30" utilizing stock valves, which are basically the same size. I think it is rediculous how bad these heads flow...what were they thinking?

The 120CFM Peak 1UZ non-vvti flow rate is almost hard to believe. Almost no cylinder head is that bad even pushrod heads with tiny ports and tiny valves.

 

[djr48312]

The 120CFM Peak 1UZ non-vvti flow rate is almost hard to believe. Almost no cyllinder head is that bad even pushrod heads with tiny ports and tiny valves.

From my recollection 1UZ was like a 1MZ with two extra bores. The cylinder heads and ports are similar on similar size bores. So they should be somewhere between 2jz and 1mz or (220-260cfm peak).