Thanks that's the thread I was talking about. Looks like a set of PPE headers is going to be installed on an HR soon.

 

They're nice but I like the F.I.'s a bit more, the PPE are step long tubes which I was told gives you more top end but the F.I. gives you more well rounded power.

 

The PPE's fit without modification to the body (hopefully we'll find out for sure about fitment soon) and can be ordered in stainless like the FI. From the other thread it sounds like they were designed on for a VHR then some changes were made in the step design because when tested on an HR it lost serious bottom end, steped primaries shouldn't mean a huge loss in low end and I'm thinking that's why this set that the member here got were redesigned. Once I get rods pistons and cams I will start making calls about the headers. I still need to finish off my suspension build before I start gathering parts for this. Then I'll call an engine builder to see what cams they recommend for my goals and go from there.

When do you plan on starting with yours?

 

Well right now I'm stationed in FL and this summer I should be moving back to WA, once I get settled in and a new DD (make the Z a project/weekend warrior). Then I'll start looking for an HR block and then build it.

 

both those headers are designed for stock cams... anyone who builds engines for a living know that the headers are matched to the cams... pretty much everything starts from your cam selection... properly paired parts will produce more power than adding up each individual parts... long tube headers are not neccessary for HRs the reason why they are sold is to mate up to the Y-pipe location... and people are suckers for the sound
at the end of the day there is only 3.5 liters of engine (214in) divided by 6 cylinders= 35square inches per cylinder per exhaust stroke or 583ml... any more than that in your primarys and it is not needed, there is other tricks of step bore, even triple step bores... do a google search for header calculator and you will need alot of numbers that are needed from the cam and volumetric efficiency
http://lmgtfy.com/?q=header+calculator
if you want maximum performance from your $$$ engine than you don't buy off the shelf parts... and the people that make custom stuff charge a shiney coin

 

Ever think of destroking the motor? Just my .02.

 

Why would anyone want to do that?

 

These motors are already oversquare, so destroking wouldn't accomplish much of anything. The r/s ratio is not the limiting factor in these engines ability to rev. If you do the calculations, you'll see that piston speeds aren't that bad, which is the "problem" that destroking would "fix". The problem is that the cams just don't make power that high, so there's not really a point.

 

The DE's rpm limiting feature is intake flow correct? I wonder what the HR's is. Rod bolts maybe.

 

Cams & heads. The internals can spin to 8k, but it doesn't make power that high. Even with all the breathing mods and a tune. No choice but to swap out the cams and possibly bump compression and/or do some headwork.

 

in stock form HRs spin to 8K and make power still!!! AM performance cars don't have "headwork" just some cleaning up in the runners, I know for a fact that 3.7liter bottom end (custom rods and pisons for +13:1 comp) with HR heads (semi stock) plus N10 Nismo cams will spin to 10,000 RPMs, the rev limiter is set at 9,500 and it pulls right on through the revlimiter! these engines make more than 400whp NA!

 

I would love a 9000 RPM redline. With the right cams and high compression do you think the stock intake manifold on the HR could flow to support power at that RPM? do you have any specs on those N10 cams, and I know you said soon but when do they become available?

I hope to start buying parts toward march timeframe. Hopefully we can get some really good info in this thread before that time.

 

We've seen with bolt-ons many hit and clear 300whp. The Japanese guys have been hitting 300whp with their DEs!

http://www.jdm-option.com/eng/featur...2/z33_v35.html

Now if DEs are breaking 300 with engine builds.

 

SG motorsport makes nearly 370whp on a DE... so what is your question??? are you asking why doesn't an HR make more power??? for one it is still 3.5 liters of displacment and for two it is not all about horsepower numbers... toque under the curve is what is needed in a race car, or street car, an HR produces a V8 "style" torque curve due to the air flow and air veolocity achieved from the heads

 

300 HP with bolt-ons is old news. It's time someone seriously builds an HR.

 

I found nothing on these nismo N10 cams.


Please respond.

 

Found this in the nismo catalogue.

13020-VQHRK 07/08 4

2007-8 HR NISMO grind cam kit. Ground on new billets, micro polished, will
work with stock ECU. Includes 4 cams. +12 whp with no other mods.
Needs our valve springs (13203-RSZ3R).

 

in cam language
S- street
C- competition
N- prototype
N10 cams are still not available yet, and just like 380RS intakes are not in a "catalogue"... when made available it is going to be a "race team part" and only certian people can get them since they need 12.5 compression, spin to 9,000 rpm bottom end, and run race gas... won't fit alot of peoples build plans

 

4.2L BC stroker. 13:1 comp pistons, ITB's, Your choice of big cams, LT headers.
i want to see what that will make ^

 

problem with BC stroker kit is you have to loose oil squirters...
here is a video of "stroked" 3.7L (not a VHR)with big cams...
<iframe width="560" height="315" src="http://www.youtube.com/embed/1L4U3coPR8U" frameborder="0" allowfullscreen></iframe>