21 turbo injectors

hello,ive got a 2.5 v6 turbo
and ive been told i can fit 21 turbo injectors,will i need the ecu mapping,
or will they run ok,
thanks for your time!
steve.

[stephendell]

Post a private message or email to Tony Smith. I think he's planning on using them in his new engine.

Ive tried this on my GTA. The standard injectors are around 185cc per min and the R21 injectors are around 285cc per min. My car made 13% co at idle with these injectors! The standard injectors on the 25 are nearly at 100% duty at around 240bhp, and with the 21 injectors you cannot turn the fuel pressure down enough to compensate, to the point where you start losing atomisation and combustion. The old 25 ecu cannot be properly remapped unless its a Baccarra Turbo model with a CAT. You can try running slightly more fuel pressure through the standard injectors with an adjustable regulator, but youll be lucky to see a 10% increase in flow, even with lots more pressure. A decent mod would be with Saab 2.3 injectors, around 215cc and run a bit more boost.

[stephendell]

Bit smoky was it or just deadly if you happened to breathe in a bit deeply!

It ran so rich, the RR tuner advised taking off the pressure feed to the regulator, so it didnt run any more fuel pressure when it came on boost.........or run about 40psi turbo boost to compensate!

I am using 21 turbo injectors in my new engine but it is 20% bigger at 3 litres. They flow virtually identically to A610 injectors and I am going to have mappable fueling so should be able to avoid any over fueling. I have read that you shouldn't run injectors too near their maximum capacity as it can cause problems and if this does happen cause one cylinder to run really lean - potentially disasterous when running alot of boost

One for David I reckon........

Given that the normal injectors are a bit on the small side once you start to tune the car - as Tony said they shouldn't be run at 100% anyway, I just wondered about David's suggestion of Saab 2.3 injectors.

Looking at the specs it would appear that Jag XJS 4.0 and 4.2 injectors run the same 214cc flow and appear to be the same configuration as GTA injectors. They are part no. 0 280 150 157 (GTA's are 0 280 150 100)
The advantage is that it'd be easier to pick up 6 together from a 6 pot Jag.

Are they low impedance like the GTA injectors though?

And would they be a direct and easy swap?

Im one step ahead! I measure the injectors on my 4.0 a few weeks back and they are 4 ohms, but ive always had dirty injector problems with this car even with new filters etc, so I dont know if its a common problem on Jags?

Truthfully, even these injectors are too small for really decent power. Rule of thumb is divide the flow rate by 5 and thats the maximum power the injector can make. So the standard GTA injectors are only really good for around 230bhp, and the saab injectors around 250bhp. The way the engine can make more power than this is by running lean, but obviously this is unsafe,

I have a new product coming soon, a fully self learning ECU that will map fuel and igntion itself, even if you change components in the engine, and will fully release the full power potential of the engine. You can then choose what size injectors you like and pick a boost level. The ignition can also be mapped to get rid of all the lag.

David, Christmas is coming so I'll be looking forward to your next update on these fully/self mapable ECUs. I'll then be planning what needs doing to get to 150 as quick as possible.

Had a 25 Baccara V6 in today, non turbo, and its got bigger injectors than the GTA turbo, by 5cc!

I think they designed the turbo engine on a Friday afternoon...