Thread: CFM mod
01-04-2010, 11:48 AM #1
guys i have just done the riva manifold upgrade and like the way it runs with the stage 1 kit with riva 13/22 dyna
then i now find out about the cfm spacer...(after putting it together)
have searched and found three threads regarding the R&D cfm spacer and nobody had posted any real world gains i.e rpm gain( R&D claim 100rpm)
before i go pulling all my good work off i would like to hear some gains from you guy of which i trust rather than a claim of 100rpm off the maker
what the score guys is this worth fitting cant do a upgraded intercooler as the ski is under warranty and i'm not doing any more mods at this time but will go balls out late 2010...
01-04-2010, 12:52 PM #2
01-04-2010, 01:02 PM #3
I would say don't bother. The gains would be minimal. Just ride it and have fun until you decide to go crazy on it.
01-04-2010, 02:14 PM #4
Paul, I've been using the CFM spacer for a year now but can't tell you exactly how much difference it made since I installed it at the same time as the manifold upgrade. It's easy to install...you only have to pull the IC, not the whole manifold again. It basically just makes the size of the housing a little bigger. The only issue is it's necessary to remove the rubber diverter piece that help push air through the core because it will no longer fit once the spacer is in place.
Here's what the instructions from R&D say:
"Removing the rubber separator will allow a small amount of air to short circuit or short cut the intercooler core which will create a vacuum on the core's outside which will help air flow through the intercooler & relieve some airflow restrictions."
I'm not sure if this is true or if it was their justification of removing it since it would no longer fit. After installing the R&D core upgrade they sent me a replacement metal diverter & it made a BIG difference in improving the cooling efficiency of the IC...my IAT's dropped 5-10*C afterwards. Here's a pic of the housing with the replacement diverter installed...it's necessary to drill a couple holes in the lip that previously held the OEM rubber piece to mount the metal replacement.
Bottom line...IMHO, installing the spacer will make a slight increase in performance by increasing airflow, but unless you fabricate a new diverter the extra air will be going straight through the housing without passing acrosse the core.
01-05-2010, 09:45 AM #5
So R&D sent you a metal diverter? Could you give us dinensions (width and height) so I could make my own?
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