How much power would they make?

http://www.z1motorsports.com/product...75cfb4c51d288a

 

For that price it does'nt matter...

 

for the price they better make some substantial(sp) power

 

They don't even show pictures of the port work, vavles, springs, or anything.....

 

maybe its a secret so nobody will copy their idea. or it doesnt do diddly squat. i dont think that port work will do much, crawford tried it and i dont think they got the numbers they were looking for. They didnt even break 300 whp from what i remember. Or they did and it wasnt worth it for the amount of power they lost below.

 

thats almost the same setup richie from australia went with..he doesn't expect power but he expects high RPM, bigger power band and no piston float.

 

do you mean piston slap or valve float.....i am unaware of the term piston float.

 

well it includes more than the nismo heads does, so i think its a good deal. in the end it only cost you 3750+ shipping which isnt bad for what you get.

 

RIP OFFF... damn thats alot of money... I can get my entire engine rebuilt for that...

 

I think Z1 should ask you to bend over along with the $4500. You can get your stock heads ported and get forged internals for MUCH less than that....

 

even if it does make a lot of power, its all gonna be up top. unless u increase the rpm limit substantially (7500rpm+) its def not worth it.

 

yea, theres always little drawbacks like that. well i thought id post it for the na junkies.

 

These are not stock heads which are ported so i wouldnt compare these to them plus your getting another set of heads so its always going to cost more than just porting the ones you've already got.

The power these make will not be all up top as it also increases your compression ratio to about 12:1, these gains will be seen everywhere.

 

would anyone know about how much the gains would be?

 

^^ valve float sorry I'm a nubb.

 

Are you sure it raises your compression?

 

from that link

Z1 VQ35 Reworked performance Head Package includes:

- Z1 performance cams/springs
- Substantial FI portwork
- Ferrea 1mm Oversize Valves
- Ferrea dual Coil valve springs
- Ferrea Titanium Retainers
- Ferrea Spring Seat Locators
- Completely Reworked VQ Heads

There is a refundable $750 core charge added to the price of the heads. To recieve the core charge back we must recieve a complete set of reworkable heads assmbled with cams and all cam caps in the factory location.

looks like its for forced induction to me because it says substantial FI portwork. it's just the stock heads rebuilt and you have to return yours unless you wanna pay the core charge

 

Apologies, I thought you were referring to the Nismo heads. My bad.

These would be FI heads as they have 1mm oversize valves. The stock valves are rather large already and going 1mm oversize may actually reduce air velocity on an NA motor. The Nismo heads are actually 1mm undersize but they flow alot more than the stock heads.

 

Murray,

The Nismo spec 1 heads don't give a lot more flow in terms of air (that was why I don't understand why would nismo bother to release it)... but Spec 2 heads are a lot better though!!!

Here is the flow test from Nismo with their heads compare to the standard ones.



cheers,

richie

 

hmm