3 words
Dont do it
unless of course you can sort out the fueling
nuff said
dum dum dah dah dah dum dum 'Freeze!'......'Rock!'
Am I the only one humming this at the moment? :$
I assume this advice stems from investigations into the old engine?
A
Formerly: '99 Black Legnum VR4
Then: '99 Toyota Corolla (succesfully adopted by Girlfriend)
Then: Audi A3, gave up on the Cabrio idea (T-boned by a guy who couldn't see in the dark. Quote "Your car is too black")
Now: Smart Cabrio (so much fun from so little HP)
Latest: BMW Z3 Coupe 2.8 (ahhhh... that's better)
It certainly does!
It is the only thing I can attribute the failing to! I did some hunting last night and my first plug experience was after fitting it.
Cool.....no fuel cuts, crap........no engine!
I have also discovered through experience that high boost is not great and doesn't yield any noticeable difference. 0.9 Bar is plenty, 0.8 works well, but 1.0 is pointless without many more ££££££££££££s!
Good info!
I've absolutely no interest in doing anything to mine, but it should be useful for those thinking of these changes.
(I was scaring the cr*p out of myself yesterday going round hairpins up mountains far too quickly - so I don't need more power)
Hmm... Curious what ya say about pushing more boost through. I'm wondering just how different the 6A12 is to the 6A13, when i pushed mine up from 14psi to about 16, the difference was about a full second down the 1/4, and 7mph.
And when I found a way to make it HOLD this boost right out to 8000rpm+, the thing was an absolute weapon, and wasn't knocking either. Can almost guarantee it would have been low 12 capable if it wasn't for a slight writing-off incident.
Oh well, next time
Got to agree with Dave, all they do is clamp the maf signal just before the fuel cut. If you run more boost = more air and more fuel needed, all you will get is more air as the fuel has been clamped, weak mixture, result det det bang.
Paul
It took a while though!Originally Posted by paulmc
If you are after any power gains - fueling should be sorted out first!
Dave: What is your NOS setup? Where can I read about it(if i missed it)? How do you sort out fueling with nitrous? Are you using additional injectors?
My NOS setup is very much home made!
It uses a single Fogger Nozzle that introduces fuel and nitrous in to the intake just before the throttle butterfly.
There are 2 solenoids, 1 for fuel and one for nitrous and a pair of jets that meter the fuel and nitrous (I have many power combinations!)
A good place to start is
Here
with a much more detailed and complete product being offered by
The Wizard of NOS
whom I had the pleasure of talking for a good while on Sunday!
.
Correct me if I'm wrong Dave as I'm new to this boost controller lark, but the boost increase to performance ratio ( if you know what I mean) is unlikely to be linear? Upping my boost from standard to 12/13psi completely transformed the car but to get the equivalent increase in performance again would need a far greater increase in boost than 0.5 bar?
I was reading an article about F1 turbo cars and they used to run 3-3.5 bar boost pressure mostly and this only increased lap times by about 2 seconds compared to cars running 1.0 bar of boost.
So this tends to agree as you say that increasing boost by an extra 0.1/ 0.2 bar over safe limits for negligble gains is pretty pointless.
2 bigdaveakers
Thanks for the links!
What's wrong with your old engine? What kind of damage are you talking about? Can you give any details?
As soon as I pull the heads off I will be posting pics :rolleyes5
Go on Dave, I wanna see that piston that kept eating your iridium plugs!!
Well nick you are just about right.
You need to take everything into perspective.
If you put 0.5 bar into you car already running 13 psi you wont feel much diff because everything is under loads more strain compared to standard.
But if you uprate your turbos, intercooler, bigger fuel pump, and then whack up the boost that is a very diff story.
you have taken your car from standard to about its max for much cheapness, any further and you need to invest a load of cash.
2 seconds a lap is massive if you watch top gear, using their fast board it is like a fiesta to a gti.
Paul
I totally agree with Dave - I can still remember the night Richie Elliott has his EVC5 fitted.
Him and his mate were playing with it but kept getting fuel cut - instead of being patient and setting it up slowly they tinkered with his FCD (increasing the max each time)........a few days later and engine has gone bang ! It was enough to put me off ever fitting one !
This is really depressing. I am sure the fcd (and other companies ) people know what they are doing, and know fine well what the end result will be. BANG . Not quite sure what the instructions say when you buy this gear but it should say in block capitals this will fek your engine( in a more political way)
It seems to me unless you read heaps of info on any product you buy now a days you are on the way to getting stung. This is a real shame for the diyer because we all think that these folkes will keep us right. NOT TRUE all they want is cash
tuning is fun all the same, and if it were not for these companies we would be pretty much stuck, Devil and deep blue sea springs to mind. :rolleyes5
Paul
IMO, like many things you should know what you are doing before playing around with this sort of device. Unfortunatly it is very tempting to just get rid of fuel cut because its annoying, without actually addressing the reason the ECU cuts fuel.
If you adjust the amount of fuel (bigger injectors, increased rail pressure) so that your car can safely cope with the extra air, then you dont need to cut the fuel for engine safety. In that case, I would think the FCD would be useful.
As a means to stop fuel cut on stock system because you have raised the boost to 1 bar, bad idea.
yup Kenneth, you hit the nail on the head there.
Paul
The problem with increasing boost and getting more power out of our cars using just boost controller and FCD is here:
- HKS FCD is a simple device that clamps MAF/MAP signal NOT ABOVE some level, but changes it along the way! For example if at 0.2 bar of boost and 2500 rpm your MAP (we have MAF/ Hz signal... just using MAP for an example) should read 2 volts (just an example...) HKS FCD will turn it into 1.78.
It can completely eliminate fuel cut by stopping short from the max. amount of voltage after which ECU cuts fuel. Lets say it is 4.5 volts... so FCD will transform that into 4 volt and will go linear from here!!!
- ECU has no idea of what really happens and does not add fuel to keep the needed A/F ratio... So if at 0.8 bar of boost it still sees some rise in Air Flow (but alreay modified and incorrect) and still adds some fuel... after 0,95 bar(remember we have a Karman MAF sensor which is limited and is useless after about 1 bar above atmospheric pressure) fuel supply is increased only by means of additional fuel line pressure (that thing is working from manifold vacuum/boost rather than ECU input), ECU thinks there is no need to adjust pulse width of injectors since there is no increase in air flow...
- So here you go - to produce power when rising boost you have to keep the A/R ratio in 12.5:1 range... what we see is rise of A/R ratio toward "lean" condition (you get it "leaner" all the way and at boost of over 0,9 bar are getting into "lean danger zone")...At 1 bar of boost with A/F ratio of 15:1 you will get knocking and no power gains... Of course there are some other things that matter such as turbo, IC, injectors efficiency, but they should cope to some extent... read this...
That's why:I think after you install e-manage (and read from its MAP pressure sensor above some point) you will be fine at higher levels of boost!
PS: If you want to keep your FCD - rise the fuel line pressure (install adjustable FPR) a bit and don't go above 1 bar too often. It is really a cheap device and does what it is supposed to do... gives you some additional power for cheap! It has its limits though!
Last edited by valmes; 25-01-2005 at 06:16 AM.
Just to clarify something for me please...
I am running 0.9 Bar with a boost controller. I now have the spiking nearly under control, and thus the constant pressure being held is 0.9 and below.
Not getting fuel cut anymore since adjusting the BC, was getting it quite often before, at various levels of boost.
Is the stock ECU providing enough fuel, i.e. is it providing more fuel now than say if it were only boosting to 0.5 Bar? Or is there a chance it could be leaning out quite badly?
I will be doing a few hrs RR soon, so I should find out then anyway, but I was just asking for opinions..
Legnum Boy
Kwik Kwak's Rule
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