Thanks for the info, will be doing bits in stages, will be interesting to know how much the Boulekos Engineering manifold cost, I know that running more than 4 injectors will mean much higher costs due to needing an ECU that can handle more injectors. I think I know where I can source an OEM 8 injector setup, will do some research into it to see if it would bolt up.
I am going to see if I can get to the project goal with 4 injectors with water/meth injection - previous project car had Bosch 1680cc injectors, direct injection isn't really new with petrol cars - there was a Mitshibishi GDi engine decades ago, I guess DI tech for petrol hasn't come along that quickly yet.
Reading up about injectors, someone found some DI injectors used by GM which flow better and fit, Bosch number 0 261 500 112 from a 2.0 Ecotec engine.
I will be buying IE rods, so will probably buy a few more of the IE parts - as you said most seem to be US based - need to work out how to fit the larger turbo and get a downpipe fitted at the same time to be able to drive it.
Hi there....
The Boulekos will cost about the same as the Stg2 HEP,and would be around £1200.
Your best bet on injectors up to around 500+bhp would be the RS3 injectors,maybe driven at a higher rail pressure,if you don't use a dual setup.
Those,and your GM injectors would need specific mapping.
DI has come quite a long way,if you take into account stratified injection and different spray patterns etc etc,plus higher injection pressures.
WMI is easy enough to fit,and would allow higher boost and lower temps,but Andy is considering removing the WMI on mine and using the ECU to deal with the rest of it.
He has another S3 running a Syvecs ECU,with a smaller GTX3576 turbo and lesser headwork than mine that turns around 630bhp,so we're hoping for at least the same on mine,with the bigger turbo,and more advanced headwork.
When it comes to the exhaust side,you'd need to consider V-band vs bolted fittings,and then you can start looking at manifolds.
Most of the good aftermarket offerings are V-banded,and the Nortech whilst not cheap,is well worth a look.
I am pretty sure that Rick@Unicorn may have something for the stock ECU and 8 injectors,but whichever solution you go for,the extra four will be on a separate LP fuel rail running at 4 bar or thereabouts.
Mine runs a set of 8L S3 injectors for the LP rail,and stock S3 injectors for the HP rail.
One other thing that was pointed out to me the other day relates to the HPFP....it's run off the inlet cam,via a tri-lobed cam,and thus runs at 3 x the engine rpm,and there are a few reports of failures at 8000rpm plus apparently,which would be 24 000 cycles/min for the HPFP.