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enigma
24-01-2005, 09:09 AM
3 words

Dont do it

unless of course you can sort out the fueling

nuff said :lipsrseal

adam_shaw
24-01-2005, 09:17 AM
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

enigma
24-01-2005, 09:22 AM
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!

adam_shaw
24-01-2005, 09:25 AM
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)

ako
24-01-2005, 09:47 AM
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 ;)

paulmc
24-01-2005, 12:53 PM
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

enigma
24-01-2005, 02:17 PM
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! :lipsrseal

valmes
24-01-2005, 02:27 PM
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?

enigma
24-01-2005, 04:19 PM
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 (http://www.nitrous.info)

with a much more detailed and complete product being offered by

The Wizard of NOS (http://noswizard.com)

whom I had the pleasure of talking for a good while on Sunday!

nick-f1
24-01-2005, 06:48 PM
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!
.
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.

valmes
24-01-2005, 09:12 PM
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?

enigma
24-01-2005, 11:28 PM
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

wirdy
24-01-2005, 11:45 PM
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!!

paulmc
25-01-2005, 12:45 AM
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

Spirit
25-01-2005, 01:15 AM
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 !

paulmc
25-01-2005, 01:30 AM
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 :sad3:

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 :D

Paul

Kenneth
25-01-2005, 01:40 AM
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.

paulmc
25-01-2005, 01:49 AM
yup Kenneth, you hit the nail on the head there.

Paul

valmes
25-01-2005, 05:59 AM
.
...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?
So this tends to agree as you say that increasing boost by an extra 0.1/ 0.2 bar over safe limits for negligible gains is pretty pointless...

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... (http://www.mkiv.com/techarticles/bcc/why_bcc/Why_the_GReddy_BCC.htm)

That's why:
...high boost is not great and doesn't yield any noticeable difference 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!

Legnum Boy
25-01-2005, 06:19 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.. :|

Polabear
25-01-2005, 08:59 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.. :|


IMHO, BIGGER Fuel pump is the first stage to go to.......rather than FCD...then BANG!!!!! at present my BC is turned off for this very reason...

enigma
25-01-2005, 09:27 AM
IMHO, BIGGER Fuel pump is the first stage to go to.......rather than FCD...then BANG!!!!! at present my BC is turned off for this very reason...

A bigger fuel pump wont help unless you increase the duty of the injectors or the size of the injectors beyond the capacity of the fuel pump. I changed mine to ensure that I had enough spare to run the nitrous (essentially another injector)

valmes
25-01-2005, 09:38 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.. :|

Do you use FCD? Consult with RR guys... They will tell you for sure (with wide band) if you're leaning out on this setup. IMO, it should be fine up to 0,9 bar... but I raised FP just to be on a safe side...

Can't wait to see pictures from Dave :) They just might turn me into "vegetarian", boost-wise :)))... nah, I'll just buy another engine!

enigma
25-01-2005, 09:45 AM
IMO, it should be fine up to 9,0 bar... but I raised FP just to be on a safe side...



WOW! :rolleyes5

Have you been on the Vodka? ;) :D :laugh:

valmes
25-01-2005, 11:34 AM
"WOW!

Have you been on the Vodka? "

No... it's too early! :D

Of course it should read 0,9 bar :)

Corrected it.

zentac
25-01-2005, 12:14 PM
The standard injectors will quite happily run an uprated pump, I am and they are fine but you need a fuel controller or similar and get it mapped properly.

enigma
25-01-2005, 12:22 PM
The capacity of the pump doesn't matter unless it is not enough!

You can have a pump that pumps 1000 litres per second and you wont gain anything (except a flat battery!) The fuel pressure is set at 43psi and the flow required is determined by the injectors.

zentac
25-01-2005, 01:37 PM
Mine was running lean with the FTO pump, so had to uprate it.

valmes
25-01-2005, 01:52 PM
Stock FTO (6a12 NA) pump vs. VR-4 (6a13TTI) pump... there is a difference!!! :)

chris g
25-01-2005, 05:12 PM
I cannot help but have a smile reading this thread

I remember the discussions here about doing things to the engine to protect it/ensure longevity if increasing boost/pursuing more power

And here we are with a number of blown engines amongst us

It seems making changes and checking value of these changes by driving in a straight line/to still be the fastest/have low ET does not work out in the end

Unless you want to loose the use of the car and sell scrap engines

Whereas you could really enjoy the speed AND handling AND 4wd AND ayc of the VR-4 by driving at tracks and especially 'ragging' it around the Nurburgring Nordschleife

And still have a car to drive AND sell on to another owner for them to enjoy the car

Hopefully around the bends rather than just up the straights

And still have a car to drive home and use each day

Kieran
25-01-2005, 05:37 PM
...Hear what you say, but that's just...............



BORING!!! :sleep: :-D


It's not been a futile excercise, just as with car manufacturers... We've only learnt about these cars, where the limits are, what to do and what not to do by making them go faster... Mitsubishi didn't produce cars like the VR-4 and the EVO without pushing the boundaries. We're just continuing their research! :-b :devil5: And you can't make an omlette without breaking a few eggs....

valmes
25-01-2005, 05:46 PM
Kieran
:beerclash :thumbsup:

I don't mind blowing up couple of engines for a "cause"!!! :)

enigma
25-01-2005, 05:51 PM
Where do we start..........!!!! :D



It seems making changes and checking value of these changes by driving in a straight line/to still be the fastest/have low ET does not work out in the end

Unless you want to loose the use of the car and sell scrap engines


Seems to be working out just fine thanks Chris, as with all things its a calculated risk. Where I may push the engine to its ultimate limits, you are pushing tyres, AYC, etc etc to their limits and will pay the price in different ways. Each to his own I guess.

I lost use of my car for 3 days, thats not a big deal really! As for the scrap engine, well its not scrap at all, it will be rebuilt stronger and faster! :p Whether it be for my car or the project car, it will be back!



Whereas you could really enjoy the speed AND handling AND 4wd AND ayc of the VR-4 by driving at tracks and especially 'ragging' it around the Nurburgring Nordschleife


I hear what you are saying/preaching about the Ring, but having been on track I am always a little disappointed with it. After several minutes it gets a little samey and the buzz kind of dwindles. Sure the VR4 handles really well, but a track car it isnt. Its fun on the track, but then so would my wifes Punto be!



And still have a car to drive AND sell on to another owner for them to enjoy the car


No one will get their mits on my car, its in the family for the duration...........I love it so much!



And still have a car to drive home and use each day


My car gets used every day, and has clocked up 30k since I bought it 18 months ago. 1 New engine at £1000 in this time is small beans compared to the £6000 I have spent of fuel, £2000 on service items, £2000 on insurance etc etc etc.

At the end of the day we all choose to do different things with our cars, to me a standard car is a complete waste of potential! Until you have experienced the thrill of developing your own systems which aid or improve power, doing your own tuning, and releasing something that is truly fast.............dont knock it! :-b

Remember, I have taken a 6 second 0-60 car and turned it in to a sub 4 second one, and it still handles :p - you cant expect to do this on a budget without risks! Why do you think the RC Developments EVO cost near £200k? Or the Sumo Skyline even more!

chris g
25-01-2005, 06:24 PM
Well, after 'timeworn defeatism', 'naysaying' its now 'boring'

The art of conversation is not dead then, at least as far as the witty brief response is concerned

Time to draw a veil over further posts I think

But before I go, Dave, it is a good track car at the Ring but despite how much I loved my VR-4 and would have preferred to keep it in the family, I cannot take it with me in the Air New Zealand 747 to Hamilton, NZ

It could have been exported by container but with a new job and a new home to get used to, dealing with the paperwork, specialised steam cleaning to protect NZ from microbes and viruses and relicensing for a year before maybe having to export it back to uk was just too much

Remember I am tired and defeated so this really was too big a task

Still, see what fun can be had in NZ - a new car, bungee jumping, river jet boating

Hope they are not too boring

Enjoy the straights Dave and dont go lean

enigma
25-01-2005, 06:30 PM
But before I go, Dave, it is a good track car at the Ring but despite how much I loved my VR-4 and would have preferred to keep it in the family, I cannot take it with me in the Air New Zealand 747 to Hamilton, NZ


It may be a good track car, but its not a great track car as it stands. Same way that its not a great drag car as it stands. Tell me how quick do you lap? Can you beat the Jag Diesel?



Still, see what fun can be had in NZ - a new car, bungee jumping, river jet boating

Hope they are not too boring


Been there, done all that, dont forget glacier walking though.



Enjoy the straights Dave and dont go lean

Been there, done that too - I am sure it wont be the last time either!

Kieran
25-01-2005, 10:55 PM
Kieran
:beerclash :thumbsup:

I don't mind blowing up couple of engines for a "cause"!!! :)


Even in the UK, Dave's proved that a Blown VR-4 engine isn't a disaster. £1000 for a 2nd hand VR-4 engine with things like the turbos, the pumps, etc. still attached is a bargain!....


If it weren't for the small problem that my front wheels would never have any traction ever again, I would be tempted myself!!! :lipsrseal :lipsrseal :$

Oh well... A truly fast car isn't just about maximum bhp or torque... So for now my efforts will focus on making my V6 transmit it's power effectively, without the alarming wheel hopping action!! :rolleyes5

enigma
25-01-2005, 11:40 PM
I have some good video footage of your car with its front left wheel smoking in 2nd gear!

It appears I was driving and you were commentating! :lipsrseal

Kieran
25-01-2005, 11:45 PM
I have some good video footage of your car with its front left wheel smoking in 2nd gear!

It appears I was driving and you were commentating! :lipsrseal

....That's not difficult to achieve in Hordak! :$ ...

When Derek had a blast up the track in it, he came back after the run and said, with wide eyes, "It's all over the f&$%@#g place isn't it?!" "I don't know how you drive that in a straight line!!!" :$ :$ :laugh:

enigma
26-01-2005, 09:15 AM
Can we recount what YOU said after driving Dereks car up the strip? Especially with the comparison to a standard VR4? :D

Kieran
26-01-2005, 12:24 PM
Can we recount what YOU said after driving Dereks car up the strip? Especially with the comparison to a standard VR4? :D

Ok, before or after I picked my jaw up off of the floor? Have a look at the "Still the fastest" thread for my brief appraisal of Derek's car... :-D