Recently I upgraded the injectors in my BMW, it's a 1991 535i M30B35 that used the green bosch design 2 injectors, which appear to be exactly the same injectors used in my '99 disco.

The new injectors are the Bosch Design III injectors which have four hole holes in a flat disc instead of the single pintle design of the older injectors.

I was able to buy 6 of the new injectors for $69 on ebay, which were pulled from a 2000 model Jeep of some kind, the new injectors are yellow.

The difference was dramatic, stunning actually. My BMW is getting better mileage, starts much quicker, and idles smooth as silk now.

This got me thinking, that maybe there would be a direct (newer design) swap for the injectors in my Disco. Admittedly I have yet to look that the injectors that are currently installed, but now I'm curious.

Has anyone else investigated this? I'm currently looking up the Bosch part numbers for the '99 4.0 injectors, so I can compare them. Seems to me like it would be a cheap upgrade that may yield a little better efficiency if not a tiny bit of performance.

Edit: Apparently the injectors used in the Rover 4.0 with the Bosch system are already the 4 hole design. Feel free to dump this thread due to it's lack of value.

 

you could still be on track, search the threads, there are members upgrading their injectors with what, I can't remember.

 

The disco 1 guys do the same upgrade, but with Mustang GT injectors. Our D2s already have 4 hole 19# injectors. I've looked extensively into upgrading. The best bet is a set of 24# injectors off of an 03 Ford F150 or similar. It would likely require a tune because that will really just dump more fuel and the spray pattern would stay the same. That's pretty much the only option. I was going to buy a set and throw them in just to see what happened, but I haven't the cash.

If you follow the link in my signature, scroll close to the bottom of the first post, click the link that says something like 24lb injector upgrade. There should be a part number in that post.

 

The injectors in the D2, are those Bosch EV6? I'm more interested to move to the updated EV14. Same connector, I believe?

 

I was mostly excited about the newer designs, compared to the single pintle design. If I were going to do forced induction I would consider the 24# injectors, but as Alex_M says the stock motronic would simply be unable to adjust the mixture lean enough to compensate.

At this point I need to focus on other issues, like back flushing the heater core, and cleaning out the rest of the cooling system when I replace everything.

Gripen, I'll need to look up the difference between the EV6 and EV14 injectors. I'm not really interested in more fuel, just improved spray patterns. To be honest, I would probably see the most benefit from simply installing new stock injectors. I have no idea how many miles these injectors have on them, because I'm assuming they were installed with the last engine.

 

After a brief investigation, the EV14 Injectors are all much higher in flow rate and pounds. Many of the EV14 injectors are 580cc at 52lbs.

I think the Rover/Motronic would freak out over the amount of fuel these injectors can deliver, however there are a myriad of options, so there might be one EV14 out there that would offer the right combination.

They may also be worth their weight in gold, but if the right match can be found they might be well worth it from an efficiency stand point.

 

The most important thing is that they're the same length from inlet to outlet. The way the fuel rail is designed, If they are longer or shorter even by a mm or two then the other side will not seat.

 

The stock injectors are 19lbs. if I recall correctly? That's nearly 200cc/min. Bosch does make an EV14 injector at 219cc/min in standard length (48.65mm going between where the injector seats between the fuel rail to the lower intake runners). However, this "production" injector (versus their high flow motorsports line) is a narrow 2-spray design rather than a conical spray. I figure with the EV14 to be the lastest port injector to be designed, it would have improved fuel atomization.