Pressure Reg RV8
darrens - 2/8/07 at 09:09 PM
Hello,
Has anyone got a pic or can tell me does the vacuum pipe for the pressure regulator come from the side of the plenum chamber (near the air bypass
valve). My misfire has returned, it's almost like there's a rev limiter at 4000rpm, but sometimes (not vey often) it's ok. I'm
beginning to think it may be fuel restriction/pressure, but the O2 reading is around 13.4 AFR on acceleration at WOT so it's a bit confusing.
Looking at the cheap things first 
cheers
[Edited on 2/8/07 by darrens]
[Edited on 2/8/07 by darrens]
mark chandler - 2/8/07 at 10:39 PM
Usual culprit will be the distributor being worn, or rotor arm breaking down on these, the ignition amps are also dodgy and have the same effect.
As long as the fuel pressure regulator goes into the pleneum it does not matter where, I think they use a drilling low down in the middle but vacumn
is vacumn.
If you pull the pipe off the block end with the engine running suck on it the revs will alter which proves it does something, if its screwed petrol
will come out of the tube as a diapham is knackered.
regards Mark
[Edited on 2/8/07 by mark chandler]
froggy - 3/8/07 at 03:17 AM
13.4 is a bit lean for wot i would try for nearer 12.5 afr. i ran my last weber set up at 5.0co at full throttle for best power.
darrens - 3/8/07 at 04:50 PM
quote:
Originally posted by froggy
13.4 is a bit lean for wot i would try for nearer 12.5 afr. i ran my last weber set up at 5.0co at full throttle for best power.
thought about that, so tried upping the amount of fuel so it ran at nearer 10-11, still did it.
Have changed dizzy cap and rotor arm, no change.
So I'm left with either, dodgy second coil (have tried another), distributor or faulty aldon ignitor. Distributor doesn't seem to have allot
of play in it, I suppose it could start and scatter the timing but I'm unsure what play in the shaft would cause that. The other option is a
faulty aldon unit, not sure how to prove this tho without replacing. Have checked the sleeve for correct No. of magnets.
Can't see MS cauing this as it has run fine. Thinking about it I can poss discount the coil as the rpm signal stay's pretty stable in MS and
on the tacho so shouldn't be the coil, unless it's not charging quick enough, but isn't that set by the aldon unit. (fixed dwell)
just think aloud!!
[Edited on 3/8/07 by darrens]