bigger injectors question

[Martin_172]

hi, ive got a mate who does a lot of work on older engines and engines that dont run with ECU's etc and he was telling me i should get injectors from a 1.4 16v for my 1.2 16v but what i was wondering is will this give a performance gain without touching the ecu (a remap)

we've already built an airbox for it to let a lot more air in (modded a standard one and modded an HKS pannel filter to fit it)

cheers

 

[Daz Clio Cup]

you can put bigger injectors on it, but your lambda sensor will detect it and get the ecu to turn the fuel down again. so no extra power i'm afraid.

 

[16v_jon]

The ECU will open the injectors so many times per second to let a specified ammount of fuel into the engine so it runs as near as possible to the 14:1 ratio, if you were to fit a larger injector (bigger holes) it would let more fuel in and run rich the oxygen sensor would realise this and tell the ecu to slow the injector pulse's down so you would be wasting your time really without a re-map.

 

[Martin_172]

right cheers guys, but worth it if i was going for a remap?

 

[BenR]

only at closed loop would it correct, and it has a max/min correction factor it can run at. On full throttle, it'll just be injecting in open loop mode with no feedback, so most likely just run rich has hell (if 1.4 injectors are a higher capacity than 1.2's).

 

[Daz Clio Cup]

right cheers guys, but worth it if i was going for a remap?

I would say that the 1.2 injectors were probally the same as the 1.4's and the 1.2's are more than likely good enough for any sensible power increase (zorst, air filter, mild cam, head work, that sort of thing) after that it's TB's anyway.........

 

[Martin_172]

na 1.4 has the same injectors as the 1.6, and 1.2 runs lean after 3,000rpm with just induction mods im told.

 

[sh33n]

Surely there's better way's too increase power, I very much doubt you'd need bigger injectors unless you had some serious mods in the first place!

 

[Daz Clio Cup]

na 1.4 has the same injectors as the 1.6, and 1.2 runs lean after 3,000rpm with just induction mods im told.

that's probably because the ecu can't cope and needs a remap. most manufacturers use the same injectors to save money and let the ecu sort out the rest, but don't quote me on that!!!

with old school carbs just an air filter meant a re-jet for more fuel but modern fuel systems should have a certain amount of flexibility built in.

 

[stan*]

better of just re-mapping to 0.88 (or there-abouts) on full load.