i've been studying up on the multi-ram system to see if it was worth removing in place of a direct air system, but it looks like i would actually loose power and torque if i did, but while running the engine to see how it all works i noticed that the plenum switchover valve isnt working at all!!!

My understanding is that is should be open on tickover and closed on throttle up to around 4000rpm when it opens again.

From what i can see all the vacuum pipes are connected and ive traced them around the engine bay, i do know that the plenum has been off the car before i got it but ive no idea if the vacuum pipes are correct.

1 more thing that may be connected is that i always get a punch of power when accelerating hard at about 4000rpm so i would have thought this might be a effect of the valve stuck open

Sounds like the front valve is not working as a step at 4k is symptomatic of exactly that.

There are two m rams. Other on the rear of the plenum. Main one on bag pipes between Maf and plenum. Revving the car aggressively will make them visibly move.

the one on the inlet is working fine can see it operating at around medium revs, shouldnt the plenum one operate just after idle i thought?  :-/

Squidy wrote on 09. Sep 2011 at 20:57:

the one on the inlet is working fine can see it operating at around medium revs, shouldnt the plenum one operate just after idle i thought?  :-/

Nah, got a rev the Tats of it to get that one to move. Don't blink either.  :)

Here's a nice contribution from Marks DTM Calib:

http://www.omegaowners.com/forum/YaBB.pl?num=1153840176

And another snip from TB:


TheBoy wrote on 25. Jul 2006 at 21:42:

Tech2 can prove the valves are working - it can manually actuate them without revving the nuts off it.

HTH

To check the rear ram is working I attached a thin wire to the plunger and fed it through one of the closes clips and left at a certain length and drove at various speeds. It will move at low revs in a higher gear 2 or 3. Drive into 3rd gear drop revs and put pedal to the metal and found that the rear ram always get activated by checking the the wire has now popped out of its clip. I could not move mine by just using the throttle.

ok cheers, think ill try the wire idea, seems a simple way of checking! thanks guys!!!