Quote:
Originally Posted by Cruger
Hi all,
I did a quick search on how to adjust the ALDA to get a bit more power off the line, but came up with nothing on how to do it properly. 
All I'm really after is for a bit more scoot when taking off so I can maneuver in traffic a bit easier/safer.
Any help?
Thanks.  |
First check your air and fuel inputs and exhaust output for no restrictions - air and fuel filters are fresh, and cat converter not plugged, before you mess with ALDA. When that's good, proceed...
by removing the ALDA off the IP completely first (yes), to see if any adjustment of it would help. (See other threads on its removal.) Just loosen it off the IP, leaving it connected to all its hosework, but not riding the injector pump.
Go for a drive with it off.
If you get immediately noticeable better off-the-line performance without the ALDA, then adjustments will yield expected improvement.
Otherwise with no extra power, then no amount of playing with ALDA (at this stage) will help your more immediate issue (whatever it is - solve that first, e.g. fix your dragging brakes, or hoist that anchor you are towing).
There are 2 ways to adjust an ALDA: shim it up, or play with the screw.
Playing with the screw risks destroying its atmospherically tight enclosure, and aneroid capsules within.
I recommend shimming the whole ALDA up where it meets the IP, or total removal and leave it off.
Note that shimming too much is equivalent to total removal, so you can fool yourself by seeing the ALDA there, yet doing no function. The "sweet spot" of a functional ALDA that you're looking for is where you still get best off-the-line performance without blowing black smoke. Start the shimming process with black smoke, then use thinner shimming to reduce smoke. You drop the shim into the nut holding the ALDA down to the IP, the type I used were copper crush washers. (I seemed to have a lot around I think from oil filter/kits you get from Benz, each one comes o-ring and crushers for the drain plug and oil canister center plug.)
A lot of people remove ALDA completely and reduce smoke with careful input of the right leg. i.e. press less on the pedal.
Black smoke is excess fuel making no extra power, ie. wasted fuel. Either YOU can modulate it with your muscles, or try to let the ALDA modulate it on your behalf. That is all it really does.
And you know that turbo is not in play off the line. You have to spool up to 2500 to make meaningful use of it. So at low speed low RPM launch stuff, that's when the ALDA is "doing its job" (of limiting your power). Worry about tweaking your turbo wastegate etc if achieving top-end power / speed is your issue. Ignore turbo things until you are scooting off the line and smiling.
I'm not a big fan of ALDA's usefulness, that is why mine sits on the bench, not on the car.
Read past posts and endless debate of pro's / con's of what else the ALDA might do in an overboost situation. My stance on that was to install a boost gauge with alarm in the car. At my altitude it's a real treat to see 1 bar / 15 psi boost under hard pressed conditions.