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Re: decipering MAP log

Posted: Thu Jul 08, 2021 12:18 pm
by stevieturbo
As you already ahve a dizzy....no doubt it has components that will offer you a viable cam trigger for sequential injection anyway.

Although for such an application, I doubt sequential would be essential anyway. Crank trigger alone would be fine ( with petrol anyway....gas might be better suited to sequential ? )

AFR measurement is an essential though

Re: decipering MAP log

Posted: Tue Dec 07, 2021 1:51 am
by ignitionautosport
Was there any result to this?
LPG needs more timing. It loves it. We use the diaphram mixers in forklifts, and they're basic to tune. Turn the knob until it's happy haha. And add timing over petrol; it's a pain when folks run both, as if you set the timing for LPG it knocks its arse off on petrol. I am guessing LPG burns slower.
Oh, I read up and saw impco mixer; I assume that model has an idle adjust knob on it and a power valve inline with the supply to inlet. I'd sit at 3k or whatever and fiddle until it's happiest, then crank in more timing. A pity I hadn't seen this sooner.

Re: decipering MAP log

Posted: Thu Sep 21, 2023 6:03 am
by landychris
It turned out that the "professional installer" did it wrong and it was their installation that was causing the issue.

I ended up getting rid of the petrol side of it and ran it LPG only, used an impco 425 mixer fixed to a holly 4 barrel throttle plate added a TPS & connected the MAP sensor and IACV. Plugged that into the original ECU so it would still control the ignition timing and advanced the timing a few degrees.

After I'd done that it ran like a beast :) Then someone wanted to buy it off me.

Now on the new boat I've got to replace the sequential LPG (prins) with something a little more accessible to the home mechanic.

Re: decipering MAP log

Posted: Thu Sep 21, 2023 11:01 am
by stevieturbo
There are lots of "professionals" out there indeed