11mm zexel pump head(M51 is 10mm) from Nissan patrol y61 2,8 td6 (RD28ETi). Theoretically gives 21% more fuel at all conditions.
New from BOSCH/ZEXEL is stupidly cheap(around 100 Euro retail price).

Would make no difference. The injection pump has an internal capacity that cannot be exceeded. Providing there is enough basic fuel feed flow, what goes through the injection pump is determined by fuel injected and fuel returned via a flow return restrictor. Flow through the injection pump cannot be increased by uprated lift pump flow rate.
 
I agree, but i'am not talking about bigger lift pump, but bigger pump rotor(high presure side - plunger/piston is bigger diameter). It's very common pratcice for bosch VE pump tuners(VAG's etc) to fit bigger head and rotor. More fuel is injected in the same time/one pump plunger stroke.
Stock M51 pump internals are good up to 220hp, with 11mm head someone(in Estonia?) achieved 290hp with big turbo. 12mm is to big, and can sieze at high RPM due to lack of lubrication and fuel cavitation.
:D
 
I agree, but i'am not talking about bigger lift pump, but bigger pump rotor(high presure side - plunger/piston is bigger diameter). It's very common pratcice for bosch VE pump tuners(VAG's etc) to fit bigger head and rotor. More fuel is injected in the same time/one pump plunger stroke.
Stock M51 pump internals are good up to 220hp, with 11mm head someone(in Estonia?) achieved 290hp with big turbo. 12mm is to big, and can sieze at high RPM due to lack of lubrication and fuel cavitation.
:D

Oh i see, but we are not talking that sort of modification. Keep things simple. This OP has a RR classic fitted with a M51 and a mechanical VE injection pump. The suggestions based on that seem to have gone some way to solving his problems up to now.;)
 
Oh i see, but we are not talking that sort of modification. Keep things simple. This OP has a RR classic fitted with a M51 and a mechanical VE injection pump. The suggestions based on that seem to have gone some way to solving his problems up to now.;)
I've no idea what was done to my setup but, don't nobody tell me again that an M51 is gutless. Here's what I do know. Full size truck (Iveco) intercooler. FIP appears to have been an electronic pump converted to mechanical. There is a sensor of some description with two cut wires opposite the inlet port. It has been tuned to make use of the extra large intercooler and happily belches black smoke on very modest usage of the accelerator. It pulls very well bolted to an LT95 although I'm assuming the gearing hasn't been changed to suit the diesel engine as there is a serious drop in engine revs when going from third to fourth gear. It accelerates like a rocket through the other gears and feels very torquey although I haven't yet had a chance to do any towing to find out it's torque performance. In my opinion, it is far superior to a TDI but I suppose 6 inline is better than 4. On a side note, the alternator hasn't got a W terminal and I have no Tacho/ rev counter. I'm assuming that, that was standard BMW spec and the tacho was driven in some other way like the ABS system or something. I have the wire in location at the alternator but just don't have anywhere to plug it into. Any suggestions as to how to tackle this problem :-/
 
I agree, but i'am not talking about bigger lift pump, but bigger pump rotor(high presure side - plunger/piston is bigger diameter). It's very common pratcice for bosch VE pump tuners(VAG's etc) to fit bigger head and rotor. More fuel is injected in the same time/one pump plunger stroke.
Stock M51 pump internals are good up to 220hp, with 11mm head someone(in Estonia?) achieved 290hp with big turbo. 12mm is to big, and can sieze at high RPM due to lack of lubrication and fuel cavitation.
:D
Great. What about famous hot start issue?
From where did you source the pump head n rotor, any web links, pls.
 
Hot start issue doesn't exist with properly adjusted timing and good battery.
Got head and rotor at Intercars(Polish car parts shop), don't think they ship international, but you should be able to order it at any BOSCH/Zexel parts dealer.
Part number is
9 461 618 910
 
Great. What about famous hot start issue?
From where did you source the pump head n rotor, any web links, pls.

Beware parts off eBay. Loads of cheap Chinese copies talked about in the VAG tuning forums and they're complete hit and miss, apparently.
 
Just a quick update re. glowplugs....Got my NGK's today and bench tested them before fitting. They take 10 seconds to begin to glow at the tip(same time it takes for the britpart ones) so,a waste of £35 quid there. I fitted them and still need 20 seconds of heat to fire it up.....FIP timing next :(
 

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