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ITB's and mapped ignition or bike carbs and mechanical dizzy
goodall - 24/8/09 at 01:46 PM

For my audi engine im not sure which to do, either way it would require buying two sets bike intakes
however what would be the likely prices of either method, megasquirt seems a very hard item find a 'normal' price for, also im not sure if it can run a 5 cylinder? i also have the issue of being too cheap to go to a rolling road, so how hard is megasquirt to map.

thats pretty much the reasons why im considering carbs, since as long the jets are about right the air going in meters how much fuel also goes in making it dead handy


omega0684 - 24/8/09 at 02:41 PM

if you run carbs your going to have to get the car set up on a rolling road to get the best performance anyway, so either way your going to have to put the car on a RR at some point,

if you are concerned about whether or not MS will run on your engine set up why don't you e-mail phil who runs the extraEFI web site, see HERE for more details.


whitestu - 24/8/09 at 03:01 PM

You don't need a rolling road to set bike carbs up. Obviously in an ideal world it would be best, but they can be made to work very well without.

Mine's been nowehere near one and goes great.



[Edited on 24/8/09 by whitestu]


MikeRJ - 24/8/09 at 03:27 PM

Megasquirt can run fuel and spark on 5 cylinder engines using the 'Extra' firmware. The limitations are that you can't run a wasted spark system with an odd number of cylinders, so you have to either run a single coil+distributor (locking the advance weights in the distributor) or use a separate coil per plug (which will require either coils with inbuilt drivers, external coil drivers or 5 drivers within the MS).

Using a coil per cylinder also requires two trigger inputs, one from the crank and one from the cam since the ECU needs to know when any particular cylinder is on it's compression stroke. A wasted spark system doesn't care if a cylinder is on the exhaust or inlet stroke, so requires only a crank sensor.


goodall - 24/8/09 at 09:45 PM

the dizzy on it is a fixed type i think, as the ignition was/is ecu controlled so should be able to be linked up there ok somehow
i know the turbo versions of this engine used coil on plug, but looks rather expensive to buy the coils

im still not 100% decided on itbs or carbs for that matter may just locost it and mod the stock system