R1minimagic
|
| posted on 8/5/06 at 06:32 PM |
|
|
Paul
The lead in petrol is there for 2 main reasons
1.) Octane booster
2.) Exhaust valve seat protection
It sounds like you have converted an engine that has a leaded head to run with fuel injection?? As most effective lead replacement additives still
use metals to provide valve seat protection i would be worried about using them with fuel injection for the same reasons as copper. Lead is also
especially bad for injector deposits, like copper. Older engines with carbs were fine running on leaded fuel but i cant think of any injection
engines that use leaded fuel...
So you could have 2 problems if you use lead replacement additives containing metals.
1) Injector fouling
2) Lambda sensor fouling
The lambda sensor relies on a zirconium dioxide element or similar to measure the oxygen content of the exhaust for the purpose of air/fuel ratio
adjustment. As metal containing additives are not 'ashless' (they cannot burn completely but form oxides) they will end up coating the
element and redusing the life of the sensor. I think they are only designed to have a life of 30-50k anyway.
I think the best thing would be to check if your head needs valve seat protection, it might be fine to run with normal unleaded fuel without any extra
protection, check with the manufacturer. I ran a mini with a leaded head on unleaded fuel for years with absolutely no problems whatsoever, maybe i
was lucky, i dont know...
|
|
|
|
|
BKLOCO
|
| posted on 8/5/06 at 07:15 PM |
|
|
All this sounds very plausible and may or may not be a cause for concern in our cars. Time will tell.
However I have just had a thought (rare for me I know).
If you are running a lambda sensor in closed loop (particularly a wide band lambda) then any "fouling" of the injectors would be
compensated for by the sensor "seeing" lean burn and increasing the injector pulse width accordingly.
Edit:
Sorry I should have made it clear I'm talking about the copper fuel line issue here not the leaded.unleaded debate.
[Edited on 8-5-06 by BKLOCO]
Experience is what you get when you don't get what you want!!! 
|
|
|
MikeR
|
| posted on 8/5/06 at 07:16 PM |
|
|
i thought one of the tricks was to alternate fuel. Didn't ford say run 1 tank in 4 with leaded for the old sierras?
|
|
|
paulf
|
| posted on 8/5/06 at 08:16 PM |
|
|
i made my injection rail from some 10mm steel tube and silver soldered stainless steel injector fittings to it.
Paul.
quote:
Originally posted by MikeR
Spoke to my mate who designs fuel Just a bit miffed i can't use it to make my fuel rail up when i go FI!
|
|
|
MikeR
|
| posted on 8/5/06 at 09:36 PM |
|
|
but where did you get the tube from? Copper pipe and bits where easy to source 
wonder if i can use that new plastic pipe builders are using?
(that was a joke)
|
|
|
R1minimagic
|
| posted on 8/5/06 at 09:43 PM |
|
|
The injector opening time is not usually adjustable with a factory ecu, maybe it could be with an aftermarket ecu. Even then, the emissions would
increase so you would probably fail the MOT test and fuel economy would suffer
The other consideration is that a fuel flow loss would usually be compensated for by the driver (you would press the throttle a bit more) but if you
are at full throttle/load that is not an option!!
[Edited on 8/5/06 by R1minimagic]
|
|
|
BKLOCO
|
| posted on 8/5/06 at 09:57 PM |
|
|
I don't think you could have read my post correctly.
I am not suggesting that you would manually increase the injector opening time.
Any ECU (original or after market) in "closed loop" opperation will adjust the injector opening time dependant on the O2 reading of the
lambda sensor.
This is how ECU's work.
Therefore it logically follows that if the injectors are not supplying sufficient fuel to give the lambda reading that the AFR table is expecting the
injector pulse width will increase to satisfy the lambda.
Experience is what you get when you don't get what you want!!!
|
|
|
R1minimagic
|
| posted on 8/5/06 at 10:08 PM |
|
|
Sorry, I am a bit pissed at the moment so i did not say what i meant. What i meant to say was there are limitations to injector lift and opening
time. Of course the pulse width/lift can increase a bit to supply more fuel but only within certain limits. The valve lift is limited by injector
design and the pulse width is limited by engine speed. If you go too far then engine power will be effected and you run into timing problems. In any
case the deposits will always cause fuel atomisation to be less efficient and ultimately reduce economy and increase emissions. OEM's always
seem to tune engines so that they only just pass whatever test is imposed upon them. Any more costs them money...
[Edited on 8/5/06 by R1minimagic]
|
|
|
highspeeddirt
|
| posted on 8/5/06 at 10:13 PM |
|
|
As I'm still building at the moment I could remove all my copper line and replace it with alloy but do I need to replace both the feed and
return lines or will just the feed be okay? Would a fuel filter before the injectors but after the copper pipe help? Just looking for options before I
rip out all the lines.
Steve
|
|
|
R1minimagic
|
| posted on 8/5/06 at 10:16 PM |
|
|
No point in just replacing feed, you would need to do both feed and return. A fuel filter will not filter out copper as it is dissolved in the fuel
although it would filter out any deposits formed before the filter.
|
|
|
highspeeddirt
|
| posted on 8/5/06 at 10:31 PM |
|
|
Okay thanks. Out come the fuel lines then
Steve
|
|
|
BKLOCO
|
| posted on 8/5/06 at 11:05 PM |
|
|
It's obviously your decision Steve but I don't think I would be too hasty if I were you.
There are plenty of people who are running Injection systems using copper pipe and there have not yet been any reported problems yet.
As has been asked already. What time period are we talking here 50,000, 100,000 200,000 miles? That could be a VERY long time in our cars.
Sometimes you maybe have to balance theory against practice.
I know what I'd do.
As I say though.
Your decision, your car.
Experience is what you get when you don't get what you want!!!
|
|
|
NS Dev
|
| posted on 9/5/06 at 08:56 AM |
|
|
I'd be inclined to agree BKloco.
We've run copper or cupro-nickel lines in a number of cars, which have done "significant" mileages (10,000+ miles) and two of those
have had more than one power run on rolling roads, were fuel injected, and showed no power difference.
Whilst I don't have the slightest doubt about the theory, in practice for "enthusiast vehicles" I think there is no problem.
Retro RWD is the way forward...........automotive fabrication, car restoration, sheetmetal work, engine conversion
retro car restoration and tuning
|
|
|
zxrlocost
|
| posted on 9/5/06 at 09:00 AM |
|
|
8mm copper pipe down the tunnel fuel pipe at the start and end and its staying simple as
apparently experts reckoned petrol was going to run out in 1976
|
PLEASE NOTE: This user is a trader who has not signed up for the LocostBuilders registration scheme. If this post is advertising a commercial product or service, please report it by clicking here.
|
Hellfire
|
| posted on 9/5/06 at 11:48 AM |
|
|
I would say as BKLOCO and NS Dev. If you have fitted your lines already, leave them and forget about them. If however, you can get an alternative
material, at a similar price and haven't fitted your fuel lines yet, then go for it. 
|
|
|
MikeR
|
| posted on 9/5/06 at 05:27 PM |
|
|
how does for free sound ?
Should have some left over when i fit it some time in 2008 as well anyone want some?
|
|
|
Hellfire
|
| posted on 9/5/06 at 05:33 PM |
|
|
Free always sounds good........
|
|
|
MikeR
|
| posted on 9/5/06 at 05:44 PM |
|
|
yeah but you prepared to wait
|
|
|
owelly
|
| posted on 16/5/06 at 01:59 AM |
|
|
I have been running a Vectra with copper fuel pipes (plastic ones were being targetted by petrol burglers!!) for three years and just short of 40,000
miles with no evidence of ill effects. I have also got in front of me the analysis results for 28seconds fuel oil (paraffin), 35seconds light fuel oil
(red diesel) and unleaded petrol that has been circulating through copper trace lines continuosly for the past 6 months, and these results have not
picked up anything detrimental to the further use of these fuels.
I'm not saying that it is wrong or right to use copper pipe (or if my analysis results contain the searches for whatever buggers up injectors),
but if I still had them fitted to my car, I certainly wouldn't consider changing them!!
http://www.ppcmag.co.uk
|
|
|
.jpg)
.jpg)
