Right basically i'm thinking that with the kind of pwer i'm going to be running with my new 1242 8v spi I may well need to upgrade the injector?

So basically anyone done this before or know which one could fit...

I also have a set of 4standard injectors from a 1372 Uno Turbo anyone have any idea if one of those would do the job?

jamie86 said:

Right basically i'm thinking that with the kind of pwer i'm going to be running with my new 1242 8v spi I may well need to upgrade the injectors?

So basically anyone done this before or know which ones could fit...

I also have a set of 4standard injectors from a 1372 Uno Turbo anyone ave any idea if one of those would do the job?

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You've just said it yourself.... SPI= Single Point Injection which means you have only 1 so you can't fit MPI injectors to your engine.

StiloSport said:

You've just said it yourself.... SPI= Single Point Injection which means you have only 1 so you can't fit MPI injectors to your engine.

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Ok didn't mean it that way meant just using one of the injectors

an injector is an injector though, it won't care if its running with friends or not. hes on about uprating the injector that is already there

arc said:

an injector is an injector though, it won't care if its running with friends or not. hes on about uprating the injector that is already there

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Think i confused things by putting "injectors" instead of "injector" now edited

I still can't see how it would work. The SPI injector is having to run 1242cc's on its own, an MPI injector only has the flow rate of a quarter of 1372cc's to deal with if you see what I mean...

StiloSport said:

I still can't see how it would work. The SPI injector is having to run 1242cc's on its own, an MPI injector only has the flow rate of a quarter of 1372cc's to deal with if you see what I mean...

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But they can handdle a lot more power than a cinq one..

i see his point though, if ur talking two 1242 engines - one mpi, one spi - the mpi injectors only be 25% of the flow rate of the spi one

jamie86 said:

But they can handdle a lot more power than a cinq one..

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But I can't see just 1 of them supplying enough fuel on its own to feed the engine. You will have to find out what the flow rates are on the injectors and go from there.

arc said:

i see his point though, if ur talking two 1242 engines - one mpi, one spi - the mpi injectors only be 25% of the flow rate of the spi one

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Thats it! Couldn't get my words out!

Yeah I get that point as well...


So maybe finding a car that has 4injectors and is a 5.0ltr and has roughly 400bhp should do th trick nicely.lol

would a single MPI injector have the same fittings as the SPI one?

yeah, fink so

http://www.sdsefi.com/injectors.htm if u wanna have a read around l

http://www.sdsefi.com/injectors.htm


http://www.megasquirt.info/v22manual/minj.htm

i believe the spi and mpi injectors are totally different. if you want an uprated injector tho it will make no difference unless you map the ecu otherwise the ecu will still only open the injectors at the normal cycle rate!


instead of uprating injectors, find a specialist who will "bore out" and clean ur old one, costs lot less than buying new ones!

Bore out your injectors? haha thats the good one!

Seriously though, why do you think you need an uprated injector? You will only need one if the standard one can not cope. Get an A/F check at a dyno to check. Replacing the injector is probably more involved than you think. It will have no benifets at all unless you need it.

SteveNZ said:

Bore out your injectors? haha thats the good one!

Seriously though, why do you think you need an uprated injector? You will only need one if the standard one can not cope. Get an A/F check at a dyno to check. Replacing the injector is probably more involved than you think. It will have no benifets at all unless you need it.

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Basically the injector can't cope with anything over 100bhp and mine will at times (Gas) be running more than that so it's either a larger single injector or get an MF2 and fit a 2nd injector in preparation for turbo conversion at some point in the future...

Well 100HP requires around about 500cc/min of fuel. Does it have 1 or 2 injectors? Either way an Uno turbo injector is way too small, its only around 200cc. I doubt they will fit either.

If you fit a larger injector you need to tune it somehow or it will run super rich most of the time.

jamie86 said:

Basically the injector can't cope with anything over 100bhp and mine will at times (Gas) be running more than that so it's either a larger single injector or get an MF2 and fit a 2nd injector in preparation for turbo conversion at some point in the future...

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You've just answered your own question.

Don't use a 'dry' Nitrous kit - i.e. just injecting gas, use a 'wet' kit - one which has a nitrous and a fuel nozzle which open at the same time. The standard ecu will always struggle if you stick a shot of nos in with no extra fuel, chances are you'll run weak - and that's when you start to have problems.

fixitagaintomorrow said:

You've just answered your own question.

Don't use a 'dry' Nitrous kit - i.e. just injecting gas, use a 'wet' kit - one which has a nitrous and a fuel nozzle which open at the same time. The standard ecu will always struggle if you stick a shot of nos in with no extra fuel, chances are you'll run weak - and that's when you start to have problems.

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Hmm yeah maybe I should just invest in an MF2 with 2nd Injector set up....