11mm pump character?!

[Piggy]

as some may know at 11pm last night I threw the 11mm pump at my green mean machine as I broke the 9mm trying to fix a leak.

been out for last hour trying a bit of fine tuning...but heres the facts:

1) Ive never driven a 11mm pumped xud
2) There aint much low down grunt like the 9mm had
3) rev the nuts off it and it flipping flies...seriously amazing
4) the boost/power comes on little later than 9mm and is mega brutal, no smooth delivery
5) The turbo was boosting to 24psi on the 9mm and spooled to that very quickly...now its 18psi...20psi at full throttle at 4500rpm in 4th
6) I cant put any more max fuel as it starts to knock
7) full throttle and I get no coaling...not even a puff

the pump is 11mm, gov modded, LDA ground
slightly advanced on timing.


thoughts? I just assumed need to drive it differently but the lack of coaling of any sort and lower boost confuses me

Wasnt sure if the LDA setup/being ground is to blame?

thoughts?

[Piggy]

any opinions?

[samass]

Dude, its been an hour. Impatient much?

[londondan86]

You should get epic coal if you floor it off boost.

[ozonehostile]

ground lda would give you less off boost coal but you should be getting some chronic smoke. sure the timing isnt too advanced?

[Piggy]

floor it off boost and no power...nothing.
5th at 45mph and if anything it slows.
sorry RE:impatience....went out again and still couldnt figure it out
Maybe timing...just been out for longer run and thats what came to mind.
Surely if max screw is to point of 'knocking' but no coaling then it has to be timing?!
retard and add more fuel?!
My other thought was maybe the LDA has been shimmed too much??

[Jonny81191]

retard and add more fuel?!

Can't hurt to try..

[Piggy]

true...true

[Tom]

I have heard darren say that an 11mm can really mess with the timing.... Not that i know in what way lol

[zx_volcane]

you running veg?

Mine doesn't coal much on veg, not like dino anyway which give huge black clouds of doom.

Could be you're bogging the crap out of the turbo with too much fuel?

Otherwise you might have throttle out a spline or too much preload on the lda ...

If you haven't got knocking on tick over or when you put your boot down, I doubt the timing is too far advanced.

[Piggy]

Got knocking on tick over and when booting....so timing should be the first thing.

Was bought off someone who already had it running so I am assuming it wasnt far off setup...timing is the only thing really I have messed with.

Yeah veg

[zx_volcane]

oh in that case then you've prob got it way too advanced

[Piggy]

Righto...its like 5degrees?! Will retard and see what happens!

[4WayDiablo]

floor it off boost and no power...nothing apart from chronic coal.
5th at 45mph and if anything it slows.

EFA
&
Mines exactly the same.
11mm

[Tom]

So its alot faster at lower psi and no coal? Doesnt sound right to me :/

[Piggy]

floor it off boost and no power...nothing apart from chronic coal.
5th at 45mph and if anything it slows.

EFA
&
Mines exactly the same.
11mm

Yeah but I aint getting chronic coaling...

I am on veg though...maybe I should stick some dino in and see what happens.

---

So its alot faster at lower psi and no coal? Doesnt sound right to me :/

...hence me threading...I know it sounds stupid though

its much slower up to 2250...like slows down slower...but on boost it pulls so hard...keep it in boost and its great...

pulls without letup to 90...theres where I stopped as roads round me are, well, lanes.
As before it would start to run out if puff at 75/80

[Dave]

Your knocking is just the shorter injection length and higher injection build pressure if your not getting coal on boost you haven't got enough fuel in top end either because of max fuel or lda settings. Even totally advanced on the slots it's fine as long as your not putting in 300hp of fuel. Sounds like you just need to up your total fuel injection.

[Piggy]

but as I said, if I increase max fuel, it starts to knock and the revs build?!
I assume thats the max fuel limit?!

Bit confused now...even more so

[Piggy]

my top boost pipe was a bit lose...so I thought AHA! I have found the issue...boost leak.



Re-positioned it and re-tightened it and went out for a drive all smug...no change, 18psi

Fiddled with the LDA and it doesnt make much difference tbh.

If I increase max fuel, the revs start to increase. but it will rev to 5500!
Get a tiny bit of coal when stationary and rev it hard, but nothing visible on the road.

Really odd. 4th gear, 40mph, 50% throttle...nothing...slowly builds, then at 2300/2500...BOOM! POWEEER!

odd

[cwspellowe]

You sure your LDA isn't on the verge of coilbinding? Sounds very much LDA related if it's doing it on part throttle, almost as if the fuelling runs away with itself when the boost builds?

[Piggy]

almost as if the fuelling runs away with itself when the boost builds?

yes exactly that...its quite an animal to drive, never really sure when its going to give you whiplash

---

I been wondering if the LDA has been shimmed too much??

[Tom]

Pretty sure you dint shim the lda.. Thats preload with the star wheel?

Thinking about it if you shimmed the lda then your power would be nothing then when the lda finally moves, bam! you get your on boost fueling... Thinking aloud really

[Piggy]

Pretty sure you dint shim the lda.. Thats preload with the star wheel?

yeah yeah my bad, thats what I mean

[cwspellowe]

It's been shimmed?

Wouldn't have thought it needed shimmed, that will reduce the travel of the LDA, possibly to the point it won't get full travel, combined with a lot of preload on the spring it would need really high boost to get decent fuel out of the pump.

Personally i'd take any shims out, back off the preload, and take it from there. Will give you a lot more smoke off boost whilst having the effect of allowing full travel of the pin, but then you can keep adjusting preload until you're happy. Oh and watch your max fuel if it's wound up to the point of the idle climbing, maybe back it off a bit until you've figured it out. You don't want to allow the LDa to give max fuel when you're on the limits of an 11mm or you'll get a ridiculous amount of fuel through it

[Piggy]

Ok thanks chap...

no, no shimmed, getting myself mixed up.

So take some preload off it, reduce max fuel a bit and see what happens?!

---

Which way is less preload on the star?

[cwspellowe]

I would do. You need to make sure the LDA's working properly, if it needs too much boost pressure to force the pin down, it may not be reaching max fuelling.

I know on my 9mm pump the LDA made a huge difference and gave it more of a "kick in the back" difference between boost/off boost when I added preload. Could be what you're experiencing but with too much preload and a coilbound spring reducing travel.

What's the pump history? Who fiddled with the LDA?

[Piggy]

Bought it off a chap on here...didnt know who built it...

I was going to strip it down, reset things, rebuild etc for the 2.1...but I was in desperate need of a pump when my 9mm broke...so threw it on in hope...but needs to last me few months till new car ready so would like it running pretty good

[sammy9212]

wind it in for less preload.

[Piggy]

wind it in for less preload.

ta

---

Hang on...Im thinking of the preload/tension internally here...not the torx bit on the exterior of the LDA...

what are you all thinking!?

[cwspellowe]

The preload. We all know what we're on about even if you don't

The torx bit on top of the LDA allows you to wind it out (anticlockwise) to further reduce off boost fuelling. It's that's been wound out all the way, and the preload on the spring (adjusted by the big cog type thing inside the housing) has been wound up too high (by winding the wheel anticlockwise) the pin will give less fuelling from its initial starting point, and be unable to drop down far enough under boost pressure to increase the fuelling because the spring has too much preload and/or the spring is going coilbound.