Megasquirt Spark Cut Launch Control In Car 2800rpm

[preludefan]

hi there, i am running megasquirt in my prelude but cant seem to get the spark cun working right- what settings are you using for launch? to clear any confusion, im using mitsubishi coilpacks fired off megasquirt directly, no edis

[jaxx751]

amazing how fast EGTs climb

[freshmakerr]

How many degrees did you delay the ignition to get the missfires ?

[dan6600]

Brilliant insight, my GTs new engine is 'planned' to be ran with Megasquirt and all these little features just make the wait even harder lol. Nice one!

[M3MN0CH6]

me too

[rb26xs14]

not to sound like a noob or anything but do the injectors still inject fuel into the cumbustion chamber during spark cut?

[unluckykid256932]

During a regular rev-limiter ECU cuts fuel and your engine runs leans and slows down. With a spark cut the spark is retarded while the fuel is injected.

[rb26xs14]

thanks man i've always wondered about that and i finally got the answer

[antifactionprogman]

@unluckykid256932, spark cut is spark cut, not spark retard. They are different things.

[Gruelius]

yes, so it doesnt lean out but i think the fuel is reduced a bit too

[merrittrs]

hi mate car sounds the nuts just wondering how you cut the spark? as ime useing megasquirt with launch control on a fiesta turbo but mine just revs no poping and banging thanx chris

[garyworthing]

Hi to get spark cut on a fiesta turbo you have to run a megasquirt with 2 coil outputs and drive the coils direct, no edis module.

[unluckykid256932]

How about wasted spark?

[zteklur]

Hi i would like a schematics of it im just installing MSnEDIS in my Ford Granada MK2 2,9 24v turbo. from what i understand the edis module jumps to limp home mode when ignition cuts= no pop or bang no fun. would be grateful for a schematic hove you wired it

thanx

[cpdask]

@garyworthing what is best with edis module or without?

[h4inf]

very nice! :)

[tony4790]

Spark cut is a good way of creating "anti lag" on a turbocharged engine which can be ideal for a good fast launch . As gary said he only uses it for a short time . WRC cars which run this for long periods of time have had millions spent on engine and turbo development and use materials which are out of economic reach for most of us for our own vehicles . I embrace users of the megasquirt as it is an affordable and adaptable method of engine tuning .

[monkeymatt2]

@tony4790 Spark Cut Rev Limiters do not create any anti-lag, anti-lag is done by squirting fuel directly into the hot exhaust manifold, causing it to explode there keeping the turbo spinning. WRC teams also do not use any super expensive turbo or engines, but have the money and resources to constantly rebuild the engine's after the wear that the race and race systems put on the engine

[foundsoul9]

@monkeymatt2 It's a bit different than anti-lag, but pre-spooling the turbo a bit on launch is possible. By retarding the ignition significantly, yet still spraying fuel, the charge burns late in the cycle and the still burning mixture spills into the exhaust when the exhaust valves open, and pre-spools the turbo. The popping is the combustion event partially occurring in the exhaust pipes, instead of wholly in the cylinders.

[Rsspecial1]

@monkeymatt2 ACTUALLY... You're 100% wrong about everything you said. Petrol is NOT injected into the exhaust manifold - thats from back in the early 80's. What it ACTUALLY is is simple air bypass, and massive ignition retard - more air passing through the head the more the turbo spools. The backfires are from the retarded ignition. WRC cars have turbo's with a maram shaft to take the heat and shock, and have 13:1 compresino ratio turbo engines... sorry but you know nothing about WRC or engines

[jusanthrday]

that just sounds like it cant be too healthy.has the spark cut off proven any long term issues for you?

[garyworthing]

No ive not had any problems from it.

It probably wouldnt be healthy to run an engine with it on all the time, but you dont, its only used occasionally for a few seconds.