Thread: where did my rpms go???
08-29-2006, 06:17 PM #1
- Join Date
- Dec 2005
where did my rpms go???
April 8400 15/20 78.7
May 8380 15/20 77.5
2 Days Ago 8200 75.1
Today No Changes 8000 15/20 73.5
It Has Racing Cam, Rr Level 1, New Rr Sc Impller, Ported Head, Nils Springs, Seat Hight In Front On One Valve Is High But Valve Was Cut To Cominsate. Boost Is At 9lbs At 8000 Today
Compression Front 115 Middle 125 Back 125
Can My Cam Be Off 1 Or 2 Teeth I Also Know Humidity Is So Vital But I Need And Have To Be At 8400rpms
What Will Take
08-29-2006, 07:05 PM #2is it safe to asume with those mods you have ditched the ceramic SC washers??? You posted that you are seeing 9psi, is that normal for 8k with your setup??? This smells of SC troubles....
08-29-2006, 07:31 PM #3
Your boost is a little low for the RR SC impeller, so my first thought would be to check the clutch slip moment. Might need a shim. After that, then the cam timing might come into play, but since you have seen 8400 RPM in the past, I would doubt that is your problem. Of course, heat is the obvious variable. What prop are you running?
08-29-2006, 09:17 PM #4
i think your RPMs went out the exhaust pipe with all the oil and blow-by bc yo chit is gone bye bye just playin, i hope
weird tho... nothing unchanged and just a steady loss of RPM? or have u been tinkering with things?
08-29-2006, 09:21 PM #5
08-29-2006, 10:05 PM #6
Definately sounds like it's time to shim the SC clutches (if they are the metal ones) I had the same problem, and the slip was on the low side. 1 more shim and it's back on the limiter.
08-29-2006, 11:16 PM #7
- Join Date
- Dec 2005
i think its the cam timing sincei have just put the head back together. it may be off 1 tooth im going to change the slop first and see if i get higher compression.
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