Jump to content
SAU Community

Recommended Posts

I am looking at an rb26 cylinder head for the rb30 twin cam head conversion.

I noticed that a place can do CNC head porting on the head, here are the flow figures,

FlowTest.jpg

Number 1 = modded intake

Number 2 = stock intake

Number 3 = modded exhaust

Number 4 = stock exhaust

I haven't seen any other figures to compare it with, if someone has them could they please let me know so I can compare.

Link to comment
https://www.sau.com.au/forums/topic/284384-rb26-cnc-head-porting/
Share on other sites

  • Replies 40
  • Created
  • Last Reply

Top Posters In This Topic

Wow, that does look amazing ! Wonder how much they charge !!.

I have a word doc with all their prices etc it is not that unreasonable.

Interesting they remove or "condition" both pads in the combustion chamber.

I think you'll find that 1 is stock intake, 2 stock exhaust, 3 modified intake 4 modified exhaust. An RB exhaust will never outflow the intake except at very low lifts. Later Mitsubishi Evo heads do for part of the range though.

They're good numbers, That looks like Audie flow software, who is the head from?

I'm confident it would be @28".

You see above #1 it says CCFM, that is calculated cfm which with Audie software is either at 10" or 28" water and if the head is flowing those numbers at 10", multiply them by 1.67 to get flow @ 28" and you have a head that flows 511cfm @ 28" intake @ .5" and 392cfm on the exhaust at the same lift.

That's in the range that a 500cu/in pro stock head flows @ .8" lift and makes around 1300hp naturally aspirated @ over 9500rpm. On an RB26 it would have a sweet spot around 20,000ish rpm..

They are very good exhaust numbers, what sized valves is the head the data is from using?

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Purchased a NC MX5 a while ago Basic suspension mods done, BC coils and Whiteline sway bars  New DBA calipers, discs and pads Added some 17 x 8 Konig Decagrams with PS5's Added some typical NA bolt on's, i.e. full exhaust and intake  Added 0.5ltrs with a MZR2.5 swap, nice bump in torques  Found a detachable hard top which is locked in for a colour match with my local paint shop in Feb 25 The little thing is awesome, I drive it everywhere, it handles like a dream whether I'm up it or just cruising  But now,  because I'm a idiot, I keep looking at turbo kits....... did I mention I'm a idiot Why is dose so appealing 
    • I would not be surprised if you are the only person on earth that has the interest/desire to do that lol.  The Haltech base map is a really good starting point, the car will fire easily and drive very well, even on mild boost levels. To me, following your advice sounds like some sort of ancient Chinese water torcher lol (this is not an insult Josh, never change <3)
    • Those car show concepts from the 2000's and 2010's like the Floria and IDx were brilliant and should've gone ahead, at least one of them. But neither Honda nor Nissan are thinking about affordable performance any more, which is truly sad.  Even if Toyota's liquid hydrogen ICE development reaches the point where it's commercially viable and the infrastructure to support it, Honda/Nissan would have to wait until Toyota allow fee access to their patents to offer it with any smaller performance models they released to take advantage of it.  
    • A sporty manual RWD coupe with a IL4 Honda engine would only be a good thing I assume we won't see anything released for a few years though, unless informal talks and designs have been going on for a few years,  and due to the current, and future, emmisions and safety requirements, I assume anything "sporty" they would do would be at least some hybrid thingie And hopefully anything they are thinking of has nice lines, without lots of plastic and fake bits hanging off it like that horrendous FK8 that looked like it was designed by a 13 year old The other issue of course in the current market is cost, currently the type R is around $70k, a twin is around $50k Meh, I'm old and grumpy and would rather buy a older model car and waste my coin on that than buying anything currently available new  
    • Nissan needs to forget about building SUVs in every size possible and bring back the damn Silvia/200sx duo to compete with the 86/brz. Maybe with the Honda type r motor pointing the right way
×
×
  • Create New...