anyone ever tuned a GRA setup, i'm needing to richen up the WOT part of the metring rod, how ever i have no idea how much to take off the diametre of the metreing rod.
any tips?

Arn't they done by jetting.

the idle and progression (cruise) circuits are.
the midrange and WOT settings are controlled by a machined rod that moved with the throttle.

Ring Swifts up and ask them...failing that, start machining up your own metering rods.I got a couple done at work. 1 is a beast, hardlu idle with it but can pull 123hprw, the other is a bit of a softie but evens the afr out from idle to 5Krpm, good for 110hprw. the original is the one I use though as it richens the idle afr up a tad but stays near stoic all the way thru to 4200 which is where the power drops off anyways, 115.3hprw.

We`re talking relatively stock engine here- highway cam, extractors and 2-1/4" system. GRA440, B2-opened up (?), big gas line and lock-offs. If I go for a dyno day with my car club or a quick bash `round the city, I chuck the big rod in. that only happens now and again.

You can start experimenting by removing the rod and placing a shim in before it, small copper washer works, with the original rod and 2 shims, mine went harder under throttle and richened up a bit up high but did`nt "feel" right in real world conditions...cold starts were no good, idle was crook...but it loved WOT though

JAIKAI

If it works on the same principle as the SU carbys, with a metering rod and jet/ fixed oriface. If the needle was moved away from the oriface, this would allow more fuel to flow. If WOT is all your interested in, then simply machine down the end of the metering rod/needle. Even filing a flat on the needle should suffice. What you are after, is to increase the area of the opening. A metering needle does not have to be round.
http://www.gasresearch.com.au/gratus.pdf

Good information, I did the same thing really...once I knew what was what. shim behind the rod is still the easiest nonpermanent way...

JAIKAI

yeah i had a read of the GRA tuning guide, i only plan on machining down the very end of the metreing rod.
WOT seems to be the main part that needs changing, cruise is good.