Hi guys,

for james and everybody who wants to fit a R kit under the bonnet , you'll find the Installation instructions here:

http://quentinazau.free.fr/R%20Kit%20Installation/

And the owners's manual here:

http://quentinazau.free.fr/R%20Kit%20Instructions/

I'll soon add an internal note from volvo france on the settings.

Quentin - THANKS!! That's EXACTLY what I need.

Just one thing - I think page two of the manual didn't upload correctly.

cheers

James

Its a shame you're not closer to me cos I've got a vacuum gauge and a CO analyser to set that up a treat!

I think the carbs are actually fairly well balanced - the biggest problem from the point of view of everyday use at the moment is the idle speed. The adjustment is fully wound out, yet it still idles at 2500-3000 with the correct (by ear) mixture. I'm not sure if that's due to a vacuum leak (being corrected by my manual enrichment), badly sealing throttles, or a bad linkage...and I don't really have the time to investigate at the moment. I need to get that sorted before getting them jetted though.

There is a problem with the throttle return spring, so that's favourite. My spares pair have extra springs on the carbs themselves, but you can't really exhange them - I've already rendered one of my spares unusable trying! Ho hum, I guess I'll just keep working on them

cheers

James

sounds like the choke is badly adjusted??

It doesn't have a choke, it has an enrichment circuit.

The problem is that (effectively) the throttle is partly open all the time - the car will hold a steady 30 in 4th...the question is why. Is the throttle literally partly open (badly adjusted, broken linkage, etc), or is there an air leak?

cheers

James

When you look inside to the carbs, can you see if it is open? There is this tool which is used for checking valve clearance, you can check with it if throttle plates are really closed. Then you know if it is vacuum leak or not?

Absolutely - that is my plan. However it's a matter of finding time to do it!

cheers

James

I would say that def the throttle linkage is incorrectly adjusted. You don't get that much adjustment on an idle speed circuit.

Is your throttle pedal adjustment/cable allowing the thing to return to closed? I bet its not. Have you tried running the car with all the linkages, choke, throttle etc disconnected and manually closing them? If that cures the probs then just a matter of adjusting the balljoints.

I would think that the choke/enrichment circuit will have an air bleed to give increased idle speed, you need to get this running without the choke before you start trying to get the idle speed down.

Thats a good point, I didn't realize you were still using the choke to keep it going.

If the mixture's so weak without choke its simply cutting straight out, I would suspect a BIG vacuum leak, ie I bet the PCV system hasn't been correctly connected and is drawing air in through the hoses.

PCV? What PCV Currently venting to the atmosphere.

You'd be amazed how small a vac leak needs to be to totally screw things up (although I've been told that throttle-body setups are more susceptible than single-throttle-point setups) - my 'big' leak wasn't visible, but it was certainly there.

I popped a pair of gaskets between the rubber spacer/isolator and the carbs, and that cleared it up a lot. I guess I ought to try one in the same place on the other side of the spacer.

As for the enrichment circuit...I'm totally in two minds. What Husky said makes a lot of sense, but then if it was bleeding that much air it wouldn't richen up as much as it does.

I've adjusted the linkage, but not recently. When I first fitted them you could press down on the linkage at idle, and the speed would drop right down. That doesn't happen any more. Maybe the rubber bands I put on the 'auxilliary spring' locations are working. Me? Ghetto?!

Another wierd thing - the 'spare' pair of carbs with the extra springs would drop back and idle correctly (no need to push the linkage, as explained above), but they would hang onto their revs for ages....probably taking 5s to drop to idle from 3k. The current 'main' pair of carbs will drop instantly to their elevated idle. Odd - maybe due to that vacuum leak (at that time unfixed)

As I said to Husky when we were discussing a RR session, the worse it runs at the moment, the less likely I am to drive it when I'm not insured with these mods declared (policy renewal at the end of the month!). That gives me time to drop the K cam in, do some work for my finals, and stop being a car nerd for a bit

cheers

James

foggyjames wrote:Another wierd thing - the 'spare' pair of carbs with the extra springs would drop back and idle correctly (no need to push the linkage, as explained above), but they would hang onto their revs for ages....probably taking 5s to drop to idle from 3k. The current 'main' pair of carbs will drop instantly to their elevated idle. Odd - maybe due to that vacuum leak (at that time unfixed)

according to the document here http://quentinazau.free.fr/R%20Kit%20In ... el0004.jpg

5 seconds for 3k-> idle is right..

try using a blowtorch to see if any air is being sucked into the carb from below. it does sound like maybe a leak, but that doesnt explain everything..

why not just put the 'spare' set on?

Putting the spare set on would seem sensible, but my main set are so much cleaner (incl internally), I decided to go with them. I've since disassembled one of the spares, and I don't think it's going back together

Very true about the 5s thing...but it sounds / feels damn stupid in reality.

cheers

James

Right, well I've added the other set of gaskets, and it seems a little smoother...maybe needs a little less choke? Very much marginal though. I'll take a can of carb cleaner to the joins and listen for it having an effect. The idle is very nice and smooth, but any leaks could be being compensated for by my use of the enrichment circuit - explaining the raised idle speed.

I also took out the venturis and chokes to look for throttle alignment. As far as I can tell, they're closing correctly, so no obvious leaks there. I adjusted the throttle balance to a more central position, and the idle is now 3000-3500....ie: not even funny any more. I'll probably set that to one extreme...it might mis-load the engine for a week or two, but a redblock can take that marginal inbalance from a strength point of view, and I can't live with a 3500rpm idle speed!

I can only assume that this is coming from the cold-start enrichment ciruit as Husky suggested. I'll take one of my spare carbs apart tonight to investigate further.

cheers

James