hi guys me and a good friend of mine are pulling my 1.2 8v engine out to re build it because it will be good lol but we got thinking is there any bigger injector that can go in my spi engine to give me a bit more power and is there another engine with taller pistons to higher the compression so we can run a high comp engine were getting it ported n polished and ecu chips are there any you guys can recommend that really work thanks
General fueling options
- Thread starter cinq55
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General fueling options
Bigger injector is not needed.
Forget polishing -- does faff all. A decent port will cost you £500+.
If you really want to run higher compression, skim the head (best done after porting as the mating faces usually get damaged). There are "skim limit" marks on the head mating surfaces -- go past those and it becomes an interference engine.
McCritch chips work. (Here, I'm assuming SPI engine.)
40mm TB, Uno 45 inlet mani, P75 cam.
Forget polishing -- does faff all. A decent port will cost you £500+.
If you really want to run higher compression, skim the head (best done after porting as the mating faces usually get damaged). There are "skim limit" marks on the head mating surfaces -- go past those and it becomes an interference engine.
McCritch chips work. (Here, I'm assuming SPI engine.)
40mm TB, Uno 45 inlet mani, P75 cam.
what fingers said...
if you want more power think of the engine as an air pump, the more air you can get to flow through it the more fuel the ecu will chuck in - you can take it along way before the injector needs upgrading as the ecu just opens the injector for longer to compensate.. Such are the wonders of electronic injection
if you want more power think of the engine as an air pump, the more air you can get to flow through it the more fuel the ecu will chuck in - you can take it along way before the injector needs upgrading as the ecu just opens the injector for longer to compensate.. Such are the wonders of electronic injection
if you want to run turbo first thing i would say is forget high compression, you want lower compression if you want to run any kind of reasonable boost really.
And yes an mf2 would work running a second injector as proven on many turbo cento's, couldn't say I would recommend that setup at all if you are starting from scratch however... Its very rudimentary way of fuelling with very little control and its not cheap either!! Run either proper aftermarket ecu or a decent piggyback like the EMU DET3 which take over all the fuelling, timing and ignition. I would also swap out the spi system for a sei mpi or P75 mpi setup and just have uprated injectors on that controlled by the aforementioned ecu or piggyback.
And yes an mf2 would work running a second injector as proven on many turbo cento's, couldn't say I would recommend that setup at all if you are starting from scratch however... Its very rudimentary way of fuelling with very little control and its not cheap either!! Run either proper aftermarket ecu or a decent piggyback like the EMU DET3 which take over all the fuelling, timing and ignition. I would also swap out the spi system for a sei mpi or P75 mpi setup and just have uprated injectors on that controlled by the aforementioned ecu or piggyback.
:yeahthat:
In essence the problem is that there's no simple way of getting the stock ECU to understand boost, and only Woj has come up with a complicated way!
In essence the problem is that there's no simple way of getting the stock ECU to understand boost, and only Woj has come up with a complicated way!
i emailed a company that sells the DET3 (digital ecu tunner 3)
and they want to no the size of the map sensor i require to turbo my cinq its a 1.2 8v spi if anyone can tell me that would be great
does anyone no any prices for the det3 's
thanks
and they want to no the size of the map sensor i require to turbo my cinq its a 1.2 8v spi if anyone can tell me that would be great
does anyone no any prices for the det3 's
thanks
3 bar map sensor will do fine
and price wise expect to pay 130-180 delivered for a new one. Bargain really.
and price wise expect to pay 130-180 delivered for a new one. Bargain really.
3 bar will allow you 2 bar = 30psi of boost. The chances of you being brave enough to run that are remote (the chances of the engine surviving in anything like one piece even remoter).
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Well, you have to take off atmospheric pressure = 1 bar. Then you have the amount of boost you can run.
So 1.5 bar = 22psi give or take
3 bar gives 44 psi or so.
Unless you're running a T jet bottom end (ideally with forged pistons) 22psi will be more than enough to destroy the engine.
So 1.5 bar = 22psi give or take
3 bar gives 44 psi or so.
Unless you're running a T jet bottom end (ideally with forged pistons) 22psi will be more than enough to destroy the engine.
If you are not going over 1.5Bar of boost, then a 2.5Bar sensor is fine.
Can't see any advantage going to a 4bar sensor.
As already said, 1.5 Bar of boost is already more than enough to have a spectacular failure.
If you go for high compression, then you will need a very low boost setup.
It makes no difference unless you're running more boost than the map sensor can interpret. All the map sensor does is measure boost (or vacuum) in the inlet manifold.
The car will need mapping to set the fuelling.
If any of this is a puzzle, you need to get a book or two on turbocharging. It's not rocket science, but neither is it simple.
Fingers I ran over 2bar ;-)
As for map sensor you want the lowest you can get away with because you lose resolution be bigger you go! (They all output 0 to 5v. 0v being total vac and 5v been the highest pressure the map sensor can register!)
Also if you say wanted a max of 1 bar boost you can't use just a 2 bar map sensor!
All turbos overshoot when they come onto boost. If you only had a 2 bar sensor and ran 1 bar of boost the turbo might boost to 1.2-3-4 for a second or so!
All fueling need to take this into account otherwise you will end up with a huge lean spike.
This is why they sell a 2.5 bar map sensor because that's the standard sensor for a turbo engine that will typically run 1 bar max
As for map sensor you want the lowest you can get away with because you lose resolution be bigger you go! (They all output 0 to 5v. 0v being total vac and 5v been the highest pressure the map sensor can register!)
Also if you say wanted a max of 1 bar boost you can't use just a 2 bar map sensor!
All turbos overshoot when they come onto boost. If you only had a 2 bar sensor and ran 1 bar of boost the turbo might boost to 1.2-3-4 for a second or so!
All fueling need to take this into account otherwise you will end up with a huge lean spike.
This is why they sell a 2.5 bar map sensor because that's the standard sensor for a turbo engine that will typically run 1 bar max
