Injector swap

[hotrodjacko]

Hi all,

Been talking to a mate with a MG ZS diesel recently abd he was saying how the MG boys like to put the injectors from the older SDi engines in the later ones for an extra 20hp or so....

And it got me thinking. Has anyone ever put the injectors from the 1.8 (or 1.9 non turbo) in their XUD? I guess they'll have a lower break pressure so can deliver a bit more fuel.

Curious,
Ross

[andyyy]

Na injector's don't fit.

But Lucas ones are lower pressure than the Bosch ones and everyone swaps go Bosch injectors as Lucas ones make less power AFAIK. Lucas are 135 bar and Bosch at 175bar

[hotrodjacko]

Thanks Andy.

What about XUD7 turbo Bosch injectors? Or are they the same as the XUD9?

[zx_volcane]

totally different injector technology in the rover engines

standard xud9 injectors are good for a fair bit of power

[andyyy]

Thanks Andy.

What about XUD7 turbo Bosch injectors? Or are they the same as the XUD9?

Those are 135 bar don't think much testing has been done with them but I can say my xud7 ran and went better with 175 bar ones out of a xud9 but could be due to the xud7 ones having 180k miles on them and the xud9 ones were fresh rebuilds from bosch. As zx_volcane says the standard ones flow more than enough. 

[hotrodjacko]

Great thanks for your help guys.

I'm aware the L-Series is DI anyway, found it interesting how the older engine injectors gained quite so much power!

Cheers,
Ross

[r3k1355]

I'm aware the L-Series is DI anyway, found it interesting how the older engine injectors gained quite so much power!

because Rover owners are cocks and can't be trusted to tell the truth?

or the stock injectors are so shit they can't provide any more fuel to make more power with.

[Ruan]

The reason you gain power from them is because of how they work... I need to do a guide video on the differences between IDI injectors and DI injectors...

IDI injectors near enough cause no restriction - especially when combined with a VE pump, you're not limited by how much the nozzle will flow, rather the ramp rate of the camplate inside the pump - remember that a VE pump can only increase injection duration it cannot and will not affect how much fuel it puts in over a given amount of time, that is a constant - you only build the line pressure up to the break point and that's it...

DI on the other hand has a cover over the nozzle and you end up building more line pressure due to the more aggressive ramp rate on the camplate, so you can turn up the pump as much as you like, but all that will happen is you extend the injection duration past the injection window of it actually able to burn the fuel properly and just end up with it burning as it goes out the exhaust valve... OR you end up with high line pressure as always, but the profile of the camplate ends up dropping before you managed to finish the injection that you wanted, due to the small nozzles, hence when you bang on a big set of nozzles, even with NO adjustments to the fuel pump, they can deliver more fuel in less time and the line pressure drops - now you've got less pressure, so worse atomisation of the fuel entering... So yes, more power, but probably a drop in economy and a bit more soot.

[hotrodjacko]

Thanks for the help guys!