Jason,

Will the valves be the same size? It's hard to tell by the pictures.


DaveO

 

Jason is more optimistic than I am!! I'm hoping for about 275+ on the dyno. SOME of the other mods we'll do at the same time include.... Nismo oil cooler, Nismo T-Stat, JIC Y-Pipe, JWT Pop Charger, AEM wide band A/F gauge, and dyno tuning by T/S. This is about as far as we can go with bolt on parts (other than a plenum) and we want to see what happens. After this project is up and running for a month we will start the new Forged motor for my car and throw on the Turbo kit as well. DAMN, I LIKE WORKING HERE!!!!

 

Good lord...your car will be a beast!

 

Enthusiasm and haste can breed disaster.... knowledge and experience are golden.

 

This is why we test the products on my car first. It will give us a much better understanding of what happens if.......

 

I think Nathan already has posted the problems you will encounter with these heads.....from his own experience of course. But I guess some people have to try for themselves.
Damn those Aussies.

 

but those were not THESE heads... different part numbers can mean a huge difference...

 

Then I am curious how many variations of the RZZ head Nismo lists.

 

so far we have 2... left side and rite side... all thats availble for heads from nismo...

 

They are THESE heads.
The part # I mentioned ( 11091- RRZ30-1) was a # that was texta,d on the box the left hand head came in.
I have had these heads ( RRZ 46cc ) since June 19 2003 but was unable to mention them as they were supplied to us on a confidential basis for racing use.
We race in a Production based series here in Australia & our sanctioning body have not yet cleared these heads for use.
We are in the process of getting the blank cams ground to suit the new heads & with new pistons, applying to use the combination in this years championship.

 

I kind of missed where this was going.... So my car is in the shop out back and the heads are almost off. Are you saying my Nismo Cams won't go into those heads? HUM... this can't be good...

 

Yeah he said that on the first page.

 

ya' guess I should have read Jason's whole thread. Missed that. Well, guess we'll confirm or prove it wrong on Wednesday..... I'm not feeling too good about this anymore. On the bright side, if that's the case then I'll pull the motor out and work on the forged bottom end instead...

 

hey since the tomeis have to be shimmed and adjusted to fit the stock head maybe they will fit this head without adjustment. call sgpracing and see if kyle knows.

 

will you still be able to run 93 octane with these heads? i think a PnP job would be a better money value personally.

 

Jeff will soon be able to confirm or refute what I have been saying about these heads.
But hears a little Math
Swept area + unswept area divided by unswept area = CR

Swept area: 3498cc devided 6 (cyls) = 583cc
Head CC 46cc + Head gasket area, aprox 5cc : total unswept area 51cc

583 + 51 = 634cc devided by 51 = 12.43 CR

 

Cool, we can deal with that.. Now if only the cams go in.. Even our race team manager is watching to see what happens. He's whining because he has to run stock cams and heads and is in the process of getting that changed as well with the racing officials.

 

hey jeff...just wondering....if u use these heads, will your stock ones be for sale? or are you gonna use them on a different engine?
thanks

 

you can run 93 with these but you will have to compromise some timing just like FI guys are having to do. also, you may be right that a P&P job will be better value especially if you have to custom grind cams to fit these heads!

This head may just be a high performance version of a stock piece intended just for the racers (as mentioned) like a Chevy "Bowtie" block that is thicker and can handle more power. These parts exist and it sort of sucks that they aren't compatible with other stock pieces. However, we shall see as soon as Jeff fits them.

 

The deck height is 0 on this engine?