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General => The garage => Topic started by: dubslug on 12 September 2004, 23:47

Title: can u help??
Post by: dubslug on 12 September 2004, 23:47
wot problems will i face if i put an 1800 webber carb on my 1600 dub??
engine spec as follows
1600 bottom end
1800 head                                                                           gti 8v cam and exhuast system??
will the carb be ok on there??
any ideas or help plz
Title: Re: can u help??
Post by: rubjonny on 13 September 2004, 10:49
Will fit OK, but you might need to have it re-jetted to suit your engine.  Some peeps get away without though.
Title: Re: can u help??
Post by: dubslug on 13 September 2004, 15:57
it does fit im juat wanting to no if i can tune it to my engine
Title: Re: can u help??
Post by: rubjonny on 13 September 2004, 16:03
Yes, you have it rejetted!  :)
Title: Re: can u help??
Post by: dubslug on 13 September 2004, 16:07
wot even though my top end is 1800??
Title: Re: can u help??
Post by: rubjonny on 13 September 2004, 16:15
Yup, you get the right jets to suit your engine.
Title: Re: can u help??
Post by: dubslug on 13 September 2004, 16:17
how much do u think ill be looking at to get the old 1600 carb refurbed or the 1800 rejetted??
Title: Re: can u help??
Post by: rubjonny on 13 September 2004, 16:26
Ah now you're asking, I have no idea, but here's a free bump untill someone who knows spots your post :)

If by 'old 1600 carb' you mean the old pierburg 2e2, it might cost a bit more becuae there are so many components on them that need doing?  It depends if there is anything wrong with it really!
Title: Re: can u help??
Post by: dubslug on 13 September 2004, 16:29
i have both a 1600 and 1800 webber, the 1600 is causing me problems, so i have fitted the 1800 but its running very rich and back firing
Title: Re: can u help??
Post by: davidhawkins_78 on 13 September 2004, 16:36
What condition are the plugs in - always a good guage of the mixture.

The jetting of a carb is a very precise skill, It's derived  from a combination of 'CC' and the revs at peak power for the main jet. Even though you have a 1800cc head? your engine will still be a 1600, so I'm not suprised it back firing !!

Your local rolling road should be able to help you - explain what u've done though !

It's not really a job for a novice - no disrespect though ... it's a very, very skilled job to get right.
Title: Re: can u help??
Post by: dubslug on 14 September 2004, 15:12
i took it to a garage and they set it back to mot standards for co2, is this ok??
also when he really revved up hard the hydro carbs went to 1200, is this ok??wot are hydro carbs??
Title: Re: can u help??
Post by: davidhawkins_78 on 14 September 2004, 15:25
If they've set it up to pass an MOT I'd imagine they've just turned the fueling down on the carb so the emissions meet the necessary standards.

They measure hydrocarbon levels as a guage of pollution ... (I think  ???)

If the car drives ok and u get better Mpg then leave it, but it'll not be producing as much Bhp as it could from a rolling road tune and re-jet!

Depends if you're fussed about a ?150 bill for say 5 bhp ...? ???
Title: Re: can u help??
Post by: dubslug on 14 September 2004, 15:43
so david are u saying i should have a 1600 carb on there???
how much would an overhaul on the old carb be roughly??as i have a 1600 webber here but the grommet around the fuel screw is fooked and needs replacing so ive been told??
Title: Re: can u help??
Post by: rubjonny on 14 September 2004, 15:49
The carb you have is fine, it just needs the fuel jets in the bottom replacing with ones to suit your engine.  The 1600 and 1800 carbs are the same, just with different fuel jets!
Title: Re: can u help??
Post by: dubslug on 14 September 2004, 15:50
how do i do that??
Title: Re: can u help??
Post by: davidhawkins_78 on 14 September 2004, 16:03
http://www.fordcaprilaser.co.uk/weber_dcoe_carbs.htm#Diagram%20of%20Main%20Jet%20assembly

Here's a nice exploded view of a complete Jet - there's various bits you have to consider in order to get things perfect, but Take the jets out your 1600 carb and compare the parts / markings to the 1800cc one. Also I'm assuming you have a single choke carb??

If the previous comment is right you'll need a smaller main jet to change the fuel / air ratio.

I know they're different brands of carb but you might be lucky and they're compatable ... In that case just swap the whole jet over and try it !
Title: Re: can u help??
Post by: dubslug on 14 September 2004, 16:08
looks a bit confusing to me, might try and find a rolling road nr basingstoke and see wot they can do etc??
knew this car would cause problems
Title: Re: can u help??
Post by: davidhawkins_78 on 14 September 2004, 16:12
lol .. chin up matey - yes it can get confusing, but that's carbs for you !!!

I spent WAAAaaay to much time with twin DCOE 40's on my previous car and the noise, power etc is lovely - living with them was hard.

Getting them jetted right - getting the idle jets right so the change from the idle jet to main jet was smooth - balancing them - getting the right lenght of trumpet - ALOT of work !!

You'll get there - and go check them jets out ;)
Title: Re: can u help??
Post by: dubslug on 14 September 2004, 16:16
im gonna go get the old 1600 carb and have a good study of it see if i can find the jets and work out how to change them lol, thatnks for ur help will get there one day, i hope as my wallets taking a battering recently  :-\
Title: Re: can u help??
Post by: davidhawkins_78 on 14 September 2004, 16:18
If you want some help take a few digi pics and i'll take a look and see what advice I can offer if that's any good ... also you ever make it to any meets / cruises ?

Might be able to take a peak for you as I get about (erm .. not in that sense !)
Title: Re: can u help??
Post by: VeeDubGTI16v on 14 September 2004, 16:23
how reliable and trouble free are they after they have been set up properly?
Title: Re: can u help??
Post by: davidhawkins_78 on 14 September 2004, 16:29
Twin 40's ???

I had no problems at all with the reliablility, but every other weekend they needed a 'tweak', but my friends always ripped the sh*t out of me for it.

They said I had a sixth sense for when I'd lost half a horse power and I'd be out there checking it over. Once they're sorted and providing you buy a good matched pair and good auxiliaries to go with them you should be fine.

Maybe a rolling road once a year unless you're mechanically minded.

Thinking of added some more grunt to your 16v ??
Title: Re: can u help??
Post by: VeeDubGTI16v on 14 September 2004, 16:33
im looking into it ;D  aiming to do something drastic next summer starting with 2.0l 9a and taking it from there
Title: Re: can u help??
Post by: davidhawkins_78 on 14 September 2004, 16:38
Nice one - go for it !!

If you need any advice on the Webers just PM me - VERY knowledgable as I built my last engine from stratch myself ... was like a bottomless pocket money wise, but 150bhp from a 1600cc engine isn't bad !

If you're after big Bhp get 45's - just be prepared for the fuel bill - full tank (?30 in that car) 120 miles !!  8)

Title: Re: can u help??
Post by: dubslug on 16 September 2004, 15:44
david where abts u from??
Title: Re: can u help??
Post by: davidhawkins_78 on 16 September 2004, 15:47
Down south Brighton way ... any good to you ??
Title: Re: can u help??
Post by: dubslug on 16 September 2004, 16:00
im up in basingstoke, would be good if u could take a look at engine some time see wot u think, would a leaking head gasket cause the revs to almost die when u stop then shoot back up??
Title: Re: can u help??
Post by: davidhawkins_78 on 16 September 2004, 16:14
I'd not be thinking that straight away - are there any other symptoms to support that ?

If you're ever in my area i'd be happy to help out ...

I'd be checking for whatever control the idle on your carb.

Try a cheat and adjust the throttle cable so it idles a lot higher than normal - see if you still get the problem then, bet you don't ;) It's just a big game of elimination . . . .
Title: Re: can u help??
Post by: dubslug on 16 September 2004, 16:25
everytime i stop at lights the revs drop down, then shoot back to normal..
1.checked and replaced all air hoses
2.replaced inlet manifold gaskets
3.changed the carb
none of this has helped, could the advance and retard bit in dizzy not be working??
car also has new fuel filter, fuel pump,battery.
its not as bad now im running the 1800 carb though but still does it, specially on cold mornings
Title: Re: can u help??
Post by: davidhawkins_78 on 16 September 2004, 16:40
Hmmmm - could be a number of things ...

I've just got a G Plate 1600 Driver for my old dear - I'll have a butchers at her's and go from there as I'm not that ofay with the specifics of these engines.

There's no ECU or Control module is there? Just sounds sooo similar to the ISV problem on GTI's. I doubt your's will have that part - but there must be an alternative to it in there somewhere.

I'll keep u posted !!
Title: Re: can u help??
Post by: dubslug on 16 September 2004, 16:49
theres a little black box thing under the wiper skuttle, not sure if thats wot u mean??
cheers for your help though  ;D
Title: Re: can u help??
Post by: davidhawkins_78 on 16 September 2004, 17:05
Listen, can you take a few pics of your engine - say divide it in to 4 sections with the air box off so I can compair the 2 cars - your's being H Plate might be different ...
Title: Re: can u help??
Post by: rubjonny on 16 September 2004, 17:11
The black box under the scuttle is the control module for the electrinic ignition.

dubslug, is it using a pierburg 2e2 carb or have you put a webber on it?  If its a pierburg it sounds like you have a vac leak somewhere, possibly the 3/4 pint unit is catching the throttle before the engine stalls?  (The big round thing on the left side with a plunger sticking out)
Title: Re: can u help??
Post by: dubslug on 16 September 2004, 17:15
its got a webber onit, the engines are the same as i have had a g and h reg. i cant do pics as im stupid on computers  :'(. but the engines are exactly the same etc
Title: Re: can u help??
Post by: rubjonny on 16 September 2004, 17:43
Not sure how the webber handles idle drop, are you using the std airbox?
Title: Re: can u help??
Post by: dubslug on 18 September 2004, 11:30
yeah thats standard, replaced it a few times hoping it was thar that was broken but no luck,even got the oil breather hose connected to see if that helps but no.
think i got a bad engine lol