The V8 Owners Forum -

I'm after some advice,I'm building a 4.6 twin turbo with the 3.9 inlet manifold and megasquirt
I'm needing a set of 36lb 3bar injectors.my question is,is there a car I can get these out that run them standard???

I would think they may be too small, I run Bosch 440cc 42lb injectors on mine and the duty gets close to maximum at times.

Ah, right it's the guy that making me the megasquirt set up that said about 36lb.....I'll go back and ask him about the 42lb.
Where did you get yours from if you don't mind me asking?

Bosch 'green giant' 42Lb/Hr injectors seem to be the default infector for boosted Rover V8's

Bosch Part number 0280155968.
Can get then all over the place, just google to find the best price. I think they were originally our of a Volvo.

Plug straight into the Rover V8 (hotwire - not flapper different fuel rail) and have a much better multi hole design than work better over different fuel pressures than the older pintle type.

Tom.

Note also the hole shape for the injector in the manifold varies between flapper and hotwire injectors, as the seals are different.

Thanks guys I'll have a look at them..its hotwire version iv got so that's not a problem

If your using a Hotwire inlet manifold the world is your oyster with inj choice, for example you can use Ford & GM V8 USA inj etc for those bigger flow rates I am using 2.0 Vauxhall Vectra inj at 3.0BAR on a RV8 to give you an example (better spray pattern higher cc) this crowd get good feedback https://www.fiveomotorsport.com/fuel-injectors/

this is interesting as my engine tuner has advised me to ditch my 440cc bosch injectors and go for some slightly smaller ones as they were over kill for my supercharged v8
now using these.
Bosch EV6 long 412cc injectors, part number 0280 155 968 (Green giant) injectors

Obvious problem with too large injectors is getting a decent idle.

Coops wrote:this is interesting as my engine tuner has advised me to ditch my 440cc bosch injectors and go for some slightly smaller ones as they were over kill for my supercharged v8
now using these.
Bosch EV6 long 412cc injectors, part number 0280 155 968 (Green giant) injectors

I would not listen to him. Even more so given such a small change, just daft.

Even for 500hp at typical pressures running at 80% duty, the calcs will recommend near 500cc

https://www.rceng.com/technical.aspx

Obviously there is room for play with those figures, but it just seems bonkers to go smaller than what you had.

Do you have any datalogs from before it all came apart ? What sort of injector duty cycles were you seeing ?

DaveEFI wrote:Obvious problem with too large injectors is getting a decent idle.

And 42's in no shape or form would be considered large, let alone too large.

Depending on his power goals they may not even be large enough.

my old 4.6 TT didnt make huge power, but I still needed to move up to 57lbs as the 42's were too small.

And whilst my LS is obviously different I run around 130lb per cylinder and have no problems at all with idle.

Quick update after all that iv gone for the Holley terminator 4 barrel efi kit

capriandyb1 wrote:Quick update after all that iv gone for the Holley terminator 4 barrel efi kit

Interesting route. Let us know how you get on.

What manifold do you intend to use?

I have found that a crossover type manifold gives better distribution with a 4 barrel tbi. ( I had 2 AFR gauges on the engine to check it)
Single plane manifolds like the Offenhausser 360 gave poor distribution on my engine. It seems to be that you are squirting fuel in rather than sucking in what the engine actually needs as in a carb set up. It could be something to do with the cylinder 5 & 7 firing sequence.

You may find that the 80lb injectors in the Terminator are a little large for an ideal tickover mixture, unless you have a chunky cam in there of course.

Thanks for the advise,I'm looking at the offenhauser 360 dual port its probably best for the low bonnet of the Capri..if you know of any other I'm open to suggestions?..theres only offenhauser or edelbrock these days thats readally available I'm finding
The engines a 4.8 rv8 forged pistons,and looking at getting the crower 50232 cam,stage 1 heads to start with
All designed to Going twin turbo in future