9mm vs 11mm pumps

[jammapic]

But you're always right... So...

Hardly!

Right about what in this particular instance?

[Jake]

[Ruan]

I just know I'm kinda right on this one...

You NEED advance to keep the combustion IN the cylinder, not still carrying on as it comes out the exhuast... If you don't run more advance, you're not taking ANY advantage of the fact an IDI can burn it ALL during it's cylinder stroke... DI it has to burn it ALL in no time at all... You need massive nozzles to make it all burn... IDI you can make it ALL burn before the exhaust valve opens - with no smoke!!

[Dum-Dum]

I just know I'm kinda right on this one...

You NEED advance to keep the combustion IN the cylinder, not still carrying on as it comes out the exhuast... If you don't run more advance, you're not taking ANY advantage of the fact an IDI can burn it ALL during it's cylinder stroke... DI it has to burn it ALL in no time at all... You need massive nozzles to make it all burn... IDI you can make it ALL burn before the exhaust valve opens - with no smoke!!

Defo to make best power but theres a 524TDS on You Tube with its exhaust exiting straight through the bonnet and that looks epic when black smoke becomes red flame at the exhaust exit.

[Ruan]

It looks epic, but what's the point..

I'd rather haul ass than have an orange glow out the pipe... The only high performance Diesel I've seen do it, is the Beans Diesel truck, but that's out the wastegate pipe and it snorts gas, so that's more something to do with it.

[Harky]

So with a BMW pump having 50% more pistons could make 315bhp plus the fact that a 10mm pump will put in 11% more fuel cos of the larger plunger. Theoretically thats almost 350bhp.

You do realise you've just set a target and thats what we'll all be expecting off you now!

[Dave]

Chris sounds like you need to join a BMW forum

[Dum-Dum]

So with a BMW pump having 50% more pistons could make 315bhp plus the fact that a 10mm pump will put in 11% more fuel cos of the larger plunger. Theoretically thats almost 350bhp.

You do realise you've just set a target and thats what we'll all be expecting off you now!

Sadly I do. TBH if I get 250bhp Ill be very very happy

Chris sounds like you need to join a BMW forum

Nah theyer all knobs, the best you get out of them is "yeah my bmw is chipped (read resistor mod) to 200bhp (read 180bhp) and is well wikid innit" or "diesel is shit, fit an M3 lump" (coming from someone with a 318i)

[silverzx]

Nah theyer all knobs, the best you get out of them is "yeah my bmw is chipped (read resistor mod) to 200bhp (read 180bhp) and is well wikid innit" or "diesel is shit, fit an M3 lump" (coming from someone with a 318i)

Standard BMW **** heads? :dance:

[d-jimbo]

In my understanding of the advanced timing being an engine killer, the greatly increased peak cylinder pressures are only partly to blame. the other factor being that the peak pressure occurs at a much steeper crank angle which results in more negative work being done (on the conrod and crank).

[Ruan]

But it doesn't all burn instantaneously when it is injected like a DI, the entire point of IDI is the very steady burn, that's why the pre combustion chamber outlet is so accurate... Yes, if your timing is TOO far advanced, you'll get the majority of the burn happening before it's any good, but you NEED the advance to have the majority of the burn happening at the RIGHT time... The injection length of an IDI is incredibly long in comparison to a DI - moreso when you've got elevated levels of IQ, but you've got to fit all the burning fuel through the Precup port, so that's fine, it keeps a steady burn throughout the stroke.

DI is completely different, it explodes almost as you inject the fuel into the cylinder in that TINY window that DIs have... If you put it in too early, you'll end up almost turning the crank backwards - yes less work done...

You've got to break some eggs to make an omlette - i.e. you need more advance, but if it's in moderation, it's helpful to get the fuel burning at the RIGHT time...

[jammapic]

make an omlette

Mmmmm.

[Dave]

This thread was really interesting, now its fizzled out.... need to post up some pump porn pics of a build...

Simple mod to get abit more travel out of your leverset... been modified since but anyway

[strictly_perv]

Have you just cut some off it?

[Ricky]

Do many of you guys who run maxed 9mm pumps have EGT gauges?

[4WayDiablo]

Do many of you guys who run maxed 9mm pumps have EGT gauges?

Afaik no one really does only a few I've heard
I suppose if you have a 9mm tuned pump then they chose to improve other things before monitoring thing like that

[mark_airey]

Do many of you guys who run maxed 9mm pumps have EGT gauges?

Ignorance is bliss as the saying goes

[Dave]

9mm is less likely to kill a turbo 'cos of egt's just cos it'll run less fuel really... so wont produce as high temp

[darrenjlobb]

Hm not always, durations tend to cause chronic temps, and pushing a 9mm hard results in long old injections, thats why 11mm + big nozzles is better if thats your plan of action, but in general, egts get worse with 11mm purely because people run stupid ammounts of fuel / smoke with them.

[Ruan]

I'm on 11mm with an EGT gauge and even with what 99% of DT owners class as "no smoke" - i.e. a light haze, you're talking 900*c - remember, the alloy that cylinder heads are made out of melts at 730*C....

[strictly_perv]

I'm on 11mm with an EGT gauge and even with what 99% of DT owners class as "no smoke" - i.e. a light haze, you're talking 900*c - remember, the alloy that cylinder heads are made out of melts at 730*C....

Best stop smoking Audi drivers then


Dave- Just to confirm, in the pic, is it ground off? I've got 2 spare Bosch pumps to have a fiddle round with.

[Ricky]

I'm on 11mm with an EGT gauge and even with what 99% of DT owners class as "no smoke" - i.e. a light haze, you're talking 900*c - remember, the alloy that cylinder heads are made out of melts at 730*C....

But how long does it take to get temps.like that?

[Ruan]

Say you haul through 3rd - by the end of third you're talking 800*C no issues, go for fourth and you'll see 900 in seconds...

It's not how quickly the engine gets there, the engine is up at that temperature no issues, it's the actual sensor taking time to heat up...

[Ricky]

True, I have been reading up a lot about different sensors and reaction time. need to get myself a gauge. sorry this thread has now gone a bit off topic!

[Dave]

Dave- Just to confirm, in the pic, is it ground off? I've got 2 spare Bosch pumps to have a fiddle round with.

No its not, its extended

[Ruan]

People who haven't got an EGT gauge will be shocked when they fit one...

It's a testament to how strong these engines are mind, people are raping them with silly exhaust and combustion temperatures yet they're still reliable.

[Ricky]

Dread to think what mine has reached in the past, I remember 4 miles-ish of straight but with a roundabout each mile, K03, gti6 backbox, 22psi and smoke on boost, must have been insane! That turbo is now dead though, and soon realised what a petrol backbox does..

I'm going off topic again :naughty:

[James]

People who haven't got an EGT gauge will be shocked when they fit one...

Hence I don't bother chief! ignorance is bliss and all that, who needs gauges!

[darrenjlobb]

People who haven't got an EGT gauge will be shocked when they fit one...

Hence I don't bother chief! ignorance is bliss and all that, who needs gauges!

400-500 quid blower is alot more expensive than an 80 quid egt gauge tho James..... you know it makes sence

[James]

only if you have a 400-500 quid blower Mr Lobb.

10x £40 blowers doesn't make....... Ah//