plentywahalla
|
 posted on 6/3/09 at 12:00 PM |
|
|
Carb or injection? advice needed !!
Thanks all for the advice on the gearbox. I have clearly tapped into a vast source of knowledge and so I will set a new conundrum.
I have bought a new 1.8 Zetec engine which came with the injection/plenum chamber set up. I now have to decide which option to go for.
Choices are:
1. Buy standard ECU for a Ford Focus, accept that I will only get 115 bhp.
2. Buy mappable aftermarket ECU, try to get more power but at higher cost and which unit to buy is a bit of a minefield.
3. Scrap the injection unit (or sell it on ebay) buy a pair of 45 dcoe webers. More power hopefully but more problems with SVA?
All advice and experiences welcome.
|
|
|
|
|
zetec
|
| posted on 6/3/09 at 12:11 PM |
|
|
If you are in this for the long term get the aftermarket ECU and fit aftermarket injection. Then if you change the engine at all you just swap it
over. The whole thing seems very complicated when you start but once you get your head arround it you will never look back! I've a mate who used
to deal with old school race cars...he just cannot believe you can up the fueling and adjust timing by tapping a key! No more farting about changing
jets etc. Your right about help, someone on here has done it all before and will be more than willing to help.
" I only registered to look at the pictures, now I'm stuck with this username for the rest of my life!"
|
|
|
irvined
|
| posted on 6/3/09 at 12:11 PM |
|
|
If your considering DCOEs, it might be easier to fit bike carbs, you can get manifolds off the shelf, and might be a bit less hit/miss than with DCOE
to get a well running setup.
I switched over to DCOES, and given the choice again id go megasquirt or bike carbs.
HTH
David
http://irvined.blogspot.com
|
|
|
Paul TigerB6
|
| posted on 6/3/09 at 12:22 PM |
|
|
As above - i'd also suggest bike carbs with a MegaJolt ECU, or bike throttle bodies with a MegaSquirt EC. I think you will have more problems
getting the standard fuel injection working with a Focus ECU than you will with an aftermarket system.
|
|
|
02GF74
|
| posted on 6/3/09 at 12:28 PM |
|
|
quote:
Originally posted by plentywahalla
I have bought a new 1.8 Zetec engine ...
3. Scrap the injection unit (or sell it on ebay) buy a pair of 45 dcoe webers. More power hopefully but more problems with SVA?
new engine - does it have nunmber so you can date it?
If it is made after august 1995, carbs will not pass emission and you need a CAT.
|
|
|
britishtrident
|
| posted on 6/3/09 at 12:57 PM |
|
|
Microsquirt --- that isn't an insult.
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
|
|
|
will121
|
| posted on 6/3/09 at 01:12 PM |
|
|
as above if a new engine and your cars not pre-registered be EFI option, mega squirt or dont dismis the use of the Ford ECU, ive just fitted
individual throttle bodies on 2litre zetec, made a plenum chamber and used the Ford MAF sensor and runs ok, should make compliying with emisions easy
and gets over the problems with bonnet clearance when using the orignal inlet manifold
ITB for ECU on a zetec
|
|
|
alistairolsen
|
| posted on 6/3/09 at 01:42 PM |
|
|
right, first of all carbs vs injection..
inection IS better, in every circumstance. Any injection setup will always give better driveability and more area under the torque curve than an
equivalent carb if both are set up correctly (that is to compare dcoes to ITBs and single choke carbs to single point injection etc.
The same argument is true of distributers vs electronic ignition.
Having established that, you come into the realms of cost...
carbs are usually more readily vailable secondhand, and even new are margionally cheaper.Especially if you go down the route of bike carbs. Remember
however that ANY good carb setup will run an ecu for the ignition anyway.
your choices as I see them:
1) std injection setup
2) webbers with ign only ecu
3)bike carbs with ign only ecu
4) ITBs and fully mappable ecu.
personally, the only reason Id use carbs is because theyre cheap which puts new webbers out the window leaving bike carbs.
By the time you get an ignition ecu, loom, bike carbs, manifold etc you may as well shell out an extra couple of hundred for the extra functionality
on the ecu and run bike throttle bodies instead IMO.
|
|
|
BenB
|
| posted on 6/3/09 at 06:11 PM |
|
|
In the long term I'd strongly suggest an aftermarket ECU so you can do fine tuning.
You can get a car running on carbs but there will always be compromises in the mapping, and carbs work by the venturi effect which, whichever way you
look at it, has to introduce a degree of restriction into the inlet.
With EFi and an aftermarket ECU you can fine tune it to the Nth degree, and concerns about granularity at low RPM are really not a consideration any
more with higher bit systems unless you've massively over-spec'd the injectors.
If you're determined to go carbs I'd recommend bike carbs rather than Webers / Dellortos. Webers were pretty advanced in the 1960s and
they sound great but they tend not to give excellent fuel economy and that sound comes at the expense of power.....
|
|
|
mark chandler
|
| posted on 6/3/09 at 06:40 PM |
|
|
megasquirt or VEMS's I recon.
Keep the existing EFI fitments or look at Bike throttle bodies and chop the manifold up to suit.
Once you get your head around tuning its great.
Regards Mark
|
|
|
coozer
|
| posted on 6/3/09 at 09:54 PM |
|
|
quote:
Originally posted by alistairolsen
right, first of all carbs vs injection..
inection IS better, in every circumstance. Any injection setup will always give better driveability and more area under the torque curve than an
equivalent carb if both are set up correctly (that is to compare dcoes to ITBs and single choke carbs to single point injection etc.
The same argument is true of distributers vs electronic ignition.
Having established that, you come into the realms of cost...
carbs are usually more readily vailable secondhand, and even new are margionally cheaper.Especially if you go down the route of bike carbs. Remember
however that ANY good carb setup will run an ecu for the ignition anyway.
your choices as I see them:
1) std injection setup
2) webbers with ign only ecu
3)bike carbs with ign only ecu
4) ITBs and fully mappable ecu.
personally, the only reason Id use carbs is because theyre cheap which puts new webbers out the window leaving bike carbs.
By the time you get an ignition ecu, loom, bike carbs, manifold etc you may as well shell out an extra couple of hundred for the extra functionality
on the ecu and run bike throttle bodies instead IMO.
Have to disagree with the first line there fella, injection is NOT better in EVERY CIRCUMSTANCE.
I have bike carbs on my ST170 and it HOWLS. Acceleration is superb. Its not even set up properly yet. I've just swapped the carbs over from a
1.8...
OK, it ticks over rough, a bit lumpy at 750rpm but I don't use that for anything over than standing still.
EFI is the result of years of emission restrictions. My carb set up cost under 150 quid and thats with the megajolt. Good setup will give just as good
a result as EFI on our cars. Carbs are constantly variable where as injectors are controlled.
If in doubt call Bogg Brothers and ask.
Steve
1972 V8 Jago
1980 Z750
|
|
|
Mark Allanson
|
| posted on 6/3/09 at 10:14 PM |
|
|
It may not have much bar room cred, but standard injection has quite a lot going for it.
I can still get acceleration to make me swear under my breath, it starts in the first millisecond EVERY time, and cost me £15 for the engine, ECU, all
the induction parts, must be a bargain.
I drove a 98 mile return trip last week in lousy conditions, driving rain and howling winds, I stuck to a steady 60mph because it was too
uncomfortable to go much quicker and burnt 1/4 of my 6 gallon tank - quite impressive.
When out for a howl, I can drain the tank in less than 120 miles - the choice is yours
If you can keep you head, whilst all others around you are losing theirs, you are not fully aware of the situation
|
|
|
plentywahalla
|
| posted on 7/3/09 at 11:03 AM |
|
|
Megasquirt rules ok!
Thanks for all input.
I will go down the aftermarket ECU route and buy a Megasquirt.
|
|
|
alistairolsen
|
| posted on 7/3/09 at 10:26 PM |
|
|
quote:
Originally posted by coozer
quote:
Originally posted by alistairolsen
right, first of all carbs vs injection..
inection IS better, in every circumstance. Any injection setup will always give better driveability and more area under the torque curve than an
equivalent carb if both are set up correctly (that is to compare dcoes to ITBs and single choke carbs to single point injection etc.
The same argument is true of distributers vs electronic ignition.
Having established that, you come into the realms of cost...
carbs are usually more readily vailable secondhand, and even new are margionally cheaper.Especially if you go down the route of bike carbs. Remember
however that ANY good carb setup will run an ecu for the ignition anyway.
your choices as I see them:
1) std injection setup
2) webbers with ign only ecu
3)bike carbs with ign only ecu
4) ITBs and fully mappable ecu.
personally, the only reason Id use carbs is because theyre cheap which puts new webbers out the window leaving bike carbs.
By the time you get an ignition ecu, loom, bike carbs, manifold etc you may as well shell out an extra couple of hundred for the extra functionality
on the ecu and run bike throttle bodies instead IMO.
Have to disagree with the first line there fella, injection is NOT better in EVERY CIRCUMSTANCE.
I have bike carbs on my ST170 and it HOWLS. Acceleration is superb. Its not even set up properly yet. I've just swapped the carbs over from a
1.8...
OK, it ticks over rough, a bit lumpy at 750rpm but I don't use that for anything over than standing still.
EFI is the result of years of emission restrictions. My carb set up cost under 150 quid and thats with the megajolt. Good setup will give just as good
a result as EFI on our cars. Carbs are constantly variable where as injectors are controlled.
If in doubt call Bogg Brothers and ask.
Steve
if you could stomach the cost, then a properly mapped ITB setup on mappable ignition would be better, its physically impossible to replicate it with
mechanical metering.
As yours was done on a budget, the effect is perfectly satisfactory.
Standard efi manifolds and the like arethe results of emissions tuning, the use of electronics to meter your fuell is merely the development of
technology.
|
|
|
