3.5 injectors

[THE 109]

anyone know how much standard injectors flow on an 86 rangy efi?
i need bigger ones but don't know where to start looking,and what's available without going too big.

[Maggot4x4]

I could be wrong as I have never owned an EFI Rover, but I seem to remember reading that V6 Commodore ones work well.

[PSI250]

i'm pretty sure they'll be
18lb/hr / 190cc/min

[Scouse]

You might find it difficult to find replacement injectors for the '86 RR.
86's & 87's have injectors with a hose "tail" on the upper side rather than the common O ring connection.

The 88 changed to the regular type injector so you might have to hunt around for a fuel rail off one of those in order to fit replacement injectors.

[THE 109]

your right about finding injectors to suit as no shops can give me any info on flow rates,they just have a listing for the engine and a part number(sometimes they have a pic of the injector).been told that holden camira and nissan skyline(RB30) are the same style,but no figures again.what do others do,buy one of each injector and get them flowed against each other to compare?surely there must be someone out there who knows more.

[PSI250]

hopefully this helps -
part no's, flow rates etc.

http://users.erols.com/srweiss/tableifc.htm

[Philip A]

I do not think that the 3.5 injectors are on that list.
The main issue is that they are the old type with pipes on top.
you would be better off with somehow getting a 3.9 rail as you can fit just about any modern injector of the correct length. the latest mod is to fit Bosch /Ford Mustang "yellow" which are 4 hole 23.5 lb. I have bosch 4 hole "pink" in my 3.9, and the idle is much better .

I may be wrong but I vaguely recall that the old 3.5 injectors were 14.5lb per hour.
The Commodore ones whether 6 or V8 are 18 lb and 3.9-4.6 "green band" are 23.5lbs per hour.
Unless you can get a pipe type injector equivalent to the old 3.5 ones, you will have to use an aftermarket ECU, as even 3litre Nissan ones would probably be a bit bigger.
So start with a 3.9 rail and you can do just about anything.
regards Philip A

[disco95]

I've got a 1991 disco with a 3.5, and a 1995 disco with a 3.9. Now I'm going to have to check, but I'm pretty sure that the rail looks the same but the injectors themselves look different. Both have a green "stripe" and connect directly to the rail. The 3.5 injectors are a lot " fatter" than the 3.9's, now I don't know if they'd be interchangable or not.
My guess is a great big MAYBE

[Philip A]

The 91 disco 3.5 has the same rail as a 3.9.
But "the 109" is referring to an 86 3.5 with flapper and these have the pipe type injectors.
AFAIK the change was in 89.
Regards Philip A

[THE 109]

thanks for the tips,keep them coming.i'm already running a haltech E6X fuel and ignition management computer because of the powerdyne super charger.the reason for the larger injector is at 4300RPM the current injectors are maxing out.do the new style injectors have the same sealing arrangement in the intake manifold?do they still use the same clamp to retain them in position?how does lb per hr convert to CC per min?what is the 4 hole injector(4 spray holes in the injector pintle)?

[Philip A]

1 yes
2 Not sure but I think the clamps on the rail will be pretty close. The injector holes must be in the same positions. On the Thor the bolt holes are in a different place,but it was near enough to fit the 3.9 rail to. the bolts do not have to go through the holes in the rail, just overlap enough to hold it down. BUT I think you will find them exactly the same.
3 Dunno but there are conversions on the net
4. 4hole ( now I think up to 8 hole) is latest tech to give better atomisation. Only became possible with laser hole drilling as compared to nozzle on old injectors.

The 23.5 Lb will be big enough as they are the same size as on a 4.6litre Mustang.
see this site
http://www.fiveomotorsport.com/Injector_SetsENGLAND.asp
Regards Philip A

[nottie]

just looked at my 86 3.5 injected engine and my 97 3.9 engine and there diffrent style injecters as stated above.
But a question for the gurus Is it possible to bolt a 3.9 manifold onto a 3.5 block and heads? or 3.9 heads onto a 3.5 block?
Just thinking it may be another way old mate can get the 3.9 style injecters onto his engine. Or it looks like the 3.9 injecters will go into the 3.5 manifold but the fuel rail is the problem

[Philip A]

Yes and yes.

But the 3.9 fuel rail should bolt on to the 3.5 manifold anyway.
There may be a difference in the way the 3.5 fuel line attaches to the 3.9 rail but this should not be insurmountable.
Regard sPhilip A

[RangingRover]

So, does anybody have a definitive spec for various rover injectors, or readily available upgrades? I had a look at the link earlier, and from what I can see, 4 litre and 4.6 injectors are actually rated for less flow than the 3.5 injectors (at 3 bar, my fuel pressure).

Quick burst with the megasquirt tonight, and the duty cycle gauge has left a nice little red telltale pinned to 100%.... Haven't got the oxy sensor hooked up yet, but i'd imagine it'd be leaning out at this point, so I'm guessing bigger injectors should go onto the to do list.... Although I probably don't need to rev it past 5,000rpm anyway

[Philip A]

If you are talking the short "green" injectors from Thor 4.0 and 4.6 .If my memory serves me correctly they are 23.5 Lb per hour at 3bar.
The long "lucas green band" on pre Thor 3.5, 3.9, 4.0, 4.6 are 23.5 Lb per hour at 2.5 bar.

Look if you fit long "green band " , (which you have to if you use a 3.9 rail, as the short Green injectors do not fit) you will have plenty of headroom.
To find flow rates of Bosch injectors, just quote the number to Bosch technical help.
The site that I detailed above has cheap NEW injectors that are direct swaps.
A commonly used cheap/used alternative that fits are Holden 007? injectors. Ie Commodore V6 or V8 injectors but they are smaller than 3.9 ones at 18lb per hour at 2.5 bar.
Regards Philip A

[THE 109]

after talking with some more fuel injection places i've decided to use standard vl turbo injectors,they flow 245cc as opposed to 185 for the rover ones.will get it dyno tuned soon.

[muddydigger]

Im told Jaguar 4.2 injectors will fit too.