9mm vs 11mm pumps

[strictly_perv]

I'm after some feed back from people who've had 9mm and 11mm heads with big turbos.

180bhp is my target car's power to weight to 200bhp per tonne which I would be very happy with

What further steps will I need to take to up the fuel on my pump for the bigger turbo as all the idlers are remover and any increase on the max fuel shoots the revs up?
I don't really want to go down the 11mm route unless I need to.



Also why do people fit an 11mm with a standard turbo?

Sorry if it's been covered before but I have had a search but couldn't find much info hifty:

Max.

[ginge191]

http://306oc.co.uk/forum/viewtopic.php?f=31&t=228

have a read

[strictly_perv]

I've read that. Good guide but not what i'm trying to find out.
Cheers though

[silverzx]

If your after reliability (which from memory I know you are) then a 9mm is the more reliable option.

By running an 11mm pump your putting the engine under a lot more strain especially seeing as you'd probably be running in excess of 30~40PSI!

If you don't mind swapping engines then go ahead, paired with a big blower it's amazing gains (as many have proved such as Darren)!

If you want reliability, then follow Dave and JP's 9mm choice. Again, they have proved that 9mm's are more then capable.

Also, the highest powered XUD I've seen proven on paper is running a 9mm and hasn't blown yet.

[strictly_perv]

Cheers for that silverzx. Yeah i'm after reliable power but sometimes with these engines I can't help but keep going up with fuel for more power. Which i'm sure everyone can understand where i'm coming from. I tried explaining to my college tutor about the turbo ect and he just thought I was talking a load of shit, so do most people infact because diesels are "shit".

So how the hell do people get more fuel out of the 9mm pumps? I can't find any information on it I wanna know how JP managed to get him pump set-up with such little smoke.

[silverzx]

Cheers for that silverzx. Yeah i'm after reliable power but sometimes with these engines I can't help but keep going up with fuel for more power. Which i'm sure everyone can understand where i'm coming from. I tried explaining to my college tutor about the turbo ect and he just thought I was talking a load of shit, so do most people infact because diesels are "shit".

So how the hell do people get more fuel out of the 9mm pumps? I can't find any information on it I wanna know how JP managed to get him pump set-up with such little smoke.

I don't have any "personal" experience with the 11mm's mind you.

Fully understand your situation with your college tutor. Not many seem to take to diesels unless it's a Vag TDi. :|

As for getting more out of the pump, anything past gov'ing, lda modifications and throttle adjustment it seems you'll have to read around the VW & US forums.

I've seen a fair few comments mentioning mod's that don't want to be shared.

Think I read about replacing some of the fuel lines that go around the pump for thicker / better flowing ones, but I'm not sure which. :oops:

[darrenjlobb]

Also, the highest powered XUD I've seen proven on paper is running a 9mm and hasn't blown yet.

Who ran over 213 on 9mm? Although pretty besides the point lol,

Reliability doesn't really come into it, you really just have to get your head around the way the pump works....

In short there are two ways to increase the ammount of fuel the engine gets, A is the change the injection length, and b is to inject more at any one time.

By putting an 11mm head on, more fuel is injected per *mm pf plunger stroke than with say a 9mm head, so in effect, you can put more fuel in, in the same duration....this will always be the case, as you cant change it other than fiddling with dv's / nozzles.

So the only way to make 9mm pumps make more fuel / power, is to increase the length of the injection more than normally possible. All the throttle lever does in a VE, is increase the injection length, and the lda allows it to increase even more. By changing out levers / lda parts etc, you can increase "travel" on the control collar, which in turn allows you to run a longer duration than is possible on a normal "stock" pump, without running silly high idles. This will only work for so long though, as longer injections eventually just start making silly heat / egts, and not much more power, which is where big nozzles / heads come in, to dump the fuel in faster (particually with DI)

IMO the bigger head makes for a much more fun drive / responsive engine (other people will agree with me here?) and also makes getting plenty of fuel much easier, BUT the biggest problem doing this at home, is is throws every aspect of the pump calibration out the window...including the timing curve, and smoke control, as your suddenly linging in double the fuel across the throttle travel, so for a well setup 11mm pump, you need to spend alot of time fiddling with timing parts / gov parts to make it controllable again.

Obviously retaining a 9mm head, allows you to control the smoke much more easily, and other than the normal timing loss's from extra traval, it remains fairly much stock, which is a good thing if you want plug and play.

Theres lots of plus and negs about both sides of it. But me personally....bigger plunger everytime!

[n0v0s]

10mm!

[silverzx]

Thanks for the information Darren, cleared a few bits up for me.

Who's actually ran a 10mm? JP did at one point iirc. Anyone else?

[darrenjlobb]

The pump I did for pompey was 10mm, but wasnt calibrated much at the time, but i assume hes still using it...

The video will be made one day, really wanna get my flow bench finished first so I can demonstrate stuff as well as just talk / show it.

[Dan!]

I think Pompey mark runs a 10mm head on his pump? If he doesnt now, im pretty sure he used to!


Edit, too late, as Darren said then I guess!

[silverzx]

The video will be made one day, really wanna get my flow bench finished first so I can demonstrate stuff as well as just talk / show it.

Good stuff, look forward to it.

[padge]

11mm all the way..

[darrenjlobb]

To be fair, if your building it yourself, its probs not a case of 11mm all the way, as it does literally RUIN the timing system, which results in chronic timing piston wear over time, and will also smoke like ***** if you leave rest of pump oem....

Could probs get away with a 10mm pump maybe.

[silverzx]

Are the disadvantages you talk of the same on the 10mm just in a milder form?

[Dan!]

Look at a cut out diagram of a Bosch VE and you should be able to see where gains can be had from the LDA system

Also, Transit govenors are different and fit. If you look at one next to a stock gov then you should be able to see a difference and understand what effect it will have

[Toby]

Also, Transit govenors are different and fit. If you look at one next to a stock gov then you should be able to see a difference and understand what effect it will have

Team Transit-Gov

[Dan!]

I dont have one though just helped you fit yours lol

[4WayDiablo]

Afaik mines been on the 11mm pump for a good 60k miles now ed shall confirm (now on 130k)

Can't really have much more on an input because I'm still on a t2 for now

[Dan!]

I dont think branding 11mm pumps as 'un-reliable' is fair tbh, less OEM is probably more apt!

[silverzx]

I wouldn't say they are unreliable but in comparison against a 9mm that they are less reliable?

There isn't exactly any advantage in terms of reliability as previously pointed out?

[n0v0s]

Afaik mines been on the 11mm pump for a good 60k miles now

From experience... In the grand scheme of things all XUD, that is pretty fkin reliable in my books!

[Joe]

Look at a cut out diagram of a Bosch VE and you should be able to see where gains can be had from the LDA system

Also, Transit govenors are different and fit. If you look at one next to a stock gov then you should be able to see a difference and understand what effect it will have

what transit mate????????

[4WayDiablo]

Look at a cut out diagram of a Bosch VE and you should be able to see where gains can be had from the LDA system

Also, Transit govenors are different and fit. If you look at one next to a stock gov then you should be able to see a difference and understand what effect it will have

what transit mate????????

The smiley ones haha best way to describe them what is it about 1995ish? Just before

[Dave]

Lol can of worms this thread

I dunno if its a misconception but neither is more reliable than the other, apart from 11mm flows more fuel, causing more power/heat which will probably destroy something else sooner. Its easier to run more boost/power on 11mm so will probably kill something like that. I like the 9mm, and with a few mods will pull 200hp, while keeping other important attributes of the pump in tact and functional

[Joe]

so what benefit does fitting a transit gov. give?

[Dave]

In reality, nothing other than if your cable catches your engine will scream its guts out. Improves throttle response mildly. I chucked one in purely cos my stock one snapped, but stock one is more accurate which helps smoke control a bunch too.

[Ed Doe]

As Phil said earlier, we 11mmd my pump at about 88k iirc, and shimmed the gov prettymuch solid too, and its now on 130k+ still going! The limiting factor is the turbo, and will also be the same for the 9mm pump really...

[strictly_perv]

Thanks for the feedback. So what are these mods to a 9mm people then? Luckily i've got a spare Bosch to play around with.

[Ed Doe]

Not trying to be obstructive, but what you're doing to the pump is fairly involved, and at this point people generally don't like to just give you all the answers. As said above, you need to get yourself on the US VAG forums; they've been doing this stuff for years, and there's a lot of info over there.

For my tuppence-orth, Darren 11mm'd my car (with my help-or hindrance!- I managed to put the camplate back in 180deg out of time, so it was advanced as f*ck and wouldn't run!) and provided you drove it like any other tuned Dtub it never smoked much, and it passed mot without touching the max. fuel screw either. I just pulled the LDA tube to the ic off, wound in the max throttle position screw and bunged a load of veg in it; fast-passed the smoke test...

So again, for a simple plug n play 'more fuel' mod, just bung one on. Until you're chasing Lobb or JP power you really dont need to be worrying about setting up the pump that much...

That was how it was back when I had my dt anyway, stuff may have changed now, but you cant do much wrong doing the above anyway....

EDIT: Also, IIRC Ruan had the same mods as mine (just 11mm'd and a cheeky gov mod) and that just made 170+hp atf with just a bigger turbo...and the headgasket had gone!.... I don't think that had had any 'fine tuning' either...