• The site migration is complete! Hopefully everything transferred properly from the multiple decades old software we were using before. If you notice any issues please let me know, thanks! Also, I'm still working on things like chatbox, etc so hopefully those will be working in the next week or two.

No More ZZP Z7 Turbo Kits...

Blacknitews6 said:
Just my opinion, but the Z3 crossover looks a little restrictive and not as efficient. The Z7 crossover had separate banks that only merged right at
the turbo inlet. I can see the Z3 is less effective since both banks, all 6 exhaust ports, will actually have to share the same space, in the crossover pipe itself, which can cause the exhaust pulses to hit eachother which will cancel out some of their energy. That might hurt exhaust velocity. I;m sure the Z3 kit will work fine on a mostly
street setup, but i'll always wonder how much more i could make with the Z7 crossover at the same boost level.:th_shakinghead2:
Click to expand...

It makes basically no difference on most of these setups. You don't have 6 cylinders worth of air trying to get into the same space at the same time. It's more like 2-3.

Pre turbo exhaust size makes almost no difference.
 


What size is the Z3 crossover? 2 inches correct? So all 6 exhaust ports have to share that small 2 inch pipe?
And there's no smooth merge, the exhaust gases will fight eachother when trying to enter the turbo. The flange is just welded to
the side of the crossover. There's no way that crossover will be as efficient as a Z7 crossover or the Cartuning Kit. Meaning at the same boost
level the Z3 crossover will make less power than a Z7 crossover or Cartuning crossover. Since all the exhaust pulses are forced into 1 pipe
could cause more boost lag?
 
GTPpower said:
It makes basically no difference on most of these setups. You don't have 6 cylinders worth of air trying to get into the same space at the same time. It's more like 2-3.

Pre turbo exhaust size makes almost no difference.
Click to expand...
So you think the Z3 crossover should make about the same power as a Z7 crossover at 15psi-18psi?
Then thats not so bad. But does it effect spool time at all? Sorry i'm a worry wart...lol.
 
GTPpower said:
It makes basically no difference on most of these setups. You don't have 6 cylinders worth of air trying to get into the same space at the same time. It's more like 2-3.

Pre turbo exhaust size makes almost no difference.
Click to expand...

x2 the power level that you're doing wont be hampered by the size of the exhaust ports.
 
Most of the crossover pipe sizes are close to the same, that's not really the issue especially since the turbo is an exhaust restriction anyway. That said I would never install a Z3 crossover. Short of dyno results proving it, I simply cannot believe that a Z7/CT style crossover will not flow and spool significantly better than a Z3. The Z3 kit is the only one that doesn't have smooth merged crossover, and I feel there was a reason for that. Of course, to each his or her own...
 
I appreciate your help. I just freaked out when i saw the Z7 was discontinued. So now i'm looking forward
to the Z3 and other mods.
 


That's what i was concerned with. The Z3 crossover i knew had to be somewhat less efficient than
a Z7 crossover. But i'm only looking to run 15psi and with heads, cam and catback i'm hoping to make
380whp+ I don't want the Stattama kit, so the Z3 in my only choice. I like the Cartuning Kit to, but i'm trying to stick with
ZZP for my parts. But i have time to think about it.
 
Blacknitews6 said:
So you think the Z3 crossover should make about the same power as a Z7 crossover at 15psi-18psi?
Then thats not so bad. But does it effect spool time at all? Sorry i'm a worry wart...lol.
Click to expand...

Power is far more dependant on the turbo than anything else. With the same turbo, you probably won't even pick up a difference on the dyno.

Spool time is dependant on pre turbo exhaust volume for the most part. If have to do some measuring with each crossover to find which is better.
 
Blacknitews6 said:
That's what i was concerned with. The Z3 crossover i knew had to be somewhat less efficient than
a Z7 crossover. But i'm only looking to run 15psi and with heads, cam and catback i'm hoping to make
380whp+ I don't want the Stattama kit, so the Z3 in my only choice. I like the Cartuning Kit to, but i'm trying to stick with
ZZP for my parts. But i have time to think about it.
Click to expand...

Don't overthink any of it....any kit will make more power than you can effectively put to the front wheels. I have one of the original Stattama prototype kits on my Park Avenue. It uses stock manifolds with a 2" crossover and a 50mm turbo with internal wastegate to a 3" downpipe. Stock motor with blocked off M90 case went 113mph with a race weight over 4,000lbs. Little turbo was all in and couldn't keep up.
 
i'm not sure if it's been said, but the cartuning turbo kit with the intercooler is like 3700, and if memory serves, the z7 ran about that with an intercooler
 
You must log in or register to reply here.
Back
Top