Author Topic: Alfetta gtv carb set up  (Read 1252 times)

0 Members and 1 Guest are viewing this topic.

Alfapride

  • Sr. Member
  • ****
  • Posts: 394
Alfetta gtv carb set up
« on: April 05, 2021, 10:40:20 AM »
Hi fellow Gtv owners wondering whatís the best carb set up you have found with a stock engine and 105 cams? I just looked at my carbs which I bought refurbed years ago to see their spec look like the below
Cylinder 1 Emulsion tube 7772.10 with 148 jet
Cylinder 2 7772.8 with 148 jet
Both with 62 idle jet

Cylinder 3 7772.11/148
Cylinder 4 7772.8/148
Both with 62 idle jet

210 mains

Not sure which choke not sure how to check them yet will look but surprised the tubes werenít matched?

The carbs are dellorto dlha 40-h

Thanks in advance for any set up suggestions
« Last Edit: April 05, 2021, 12:32:18 PM by Alfapride »
Alfa 33 16v
Alfa 116 Giulietta
Alfa 116 Alfetta GTV
Alfa MY2004 147 TI
Alfa MY19 Giulia Veloce

carlo rossi

  • Hero Member
  • *****
  • Posts: 708
  • AROCA Member #: 8733
Re: Alfetta gtv carb set up
« Reply #1 on: April 05, 2021, 12:47:51 PM »
First step
When you say you have 105 cams what are the next 2 numbers after that
Before you jet this is very important to know
You also want the emulsion jet to 7772.8 all 4 of them
Then we will move on
Happy Easter
current cars
red 83 gtv 2.0


previous cars
Red 76 1.2/1.5 alfasud ti
white 79 alfetta 2000
alfetta 74 1.8
escort Lotus twin cam
bikes
ducati 900 ss 1979
moto morini 3 1/2 sport 1975/6
Moto morini 3 1/2 valentini speciale 77 oh and a deltek rockhopper

Alfapride

  • Sr. Member
  • ****
  • Posts: 394
Re: Alfetta gtv carb set up
« Reply #2 on: April 05, 2021, 01:15:16 PM »
Hi Carlo happy Easter to you also! I donít know the number now but I know itís the 105 pre emission cams both for the inlet and exhaust it was an upgrade done long ago and recently verified when I got the steam seals replaced and tappets adjusted - where do you recommend I buy the matched emulsion tubes?
Alfa 33 16v
Alfa 116 Giulietta
Alfa 116 Alfetta GTV
Alfa MY2004 147 TI
Alfa MY19 Giulia Veloce

carlo rossi

  • Hero Member
  • *****
  • Posts: 708
  • AROCA Member #: 8733
Re: Alfetta gtv carb set up
« Reply #3 on: April 05, 2021, 01:24:56 PM »
I go to dellorto uk Iíll assume they are 10548 cans
Youíll need the emulsions air correctors 210
Mains 152
Idle 58
Accelerator pump jet 38 x4
« Last Edit: April 05, 2021, 01:27:00 PM by carlo rossi »
current cars
red 83 gtv 2.0


previous cars
Red 76 1.2/1.5 alfasud ti
white 79 alfetta 2000
alfetta 74 1.8
escort Lotus twin cam
bikes
ducati 900 ss 1979
moto morini 3 1/2 sport 1975/6
Moto morini 3 1/2 valentini speciale 77 oh and a deltek rockhopper

Alfapride

  • Sr. Member
  • ****
  • Posts: 394
Re: Alfetta gtv carb set up
« Reply #4 on: April 05, 2021, 01:29:14 PM »
Hi Carlo I have a spare cam pretty same one in the car says 10548 03 200 if that helps Iíll get the bits for the car and revert thanks for the advice...how do I check the choke or access them? I recall being told 33mm was way to go but not sure whatís in mine?
Alfa 33 16v
Alfa 116 Giulietta
Alfa 116 Alfetta GTV
Alfa MY2004 147 TI
Alfa MY19 Giulia Veloce

Alfapride

  • Sr. Member
  • ****
  • Posts: 394
Re: Alfetta gtv carb set up
« Reply #5 on: April 05, 2021, 01:30:19 PM »
Also how would I check the accelerator pump?
Alfa 33 16v
Alfa 116 Giulietta
Alfa 116 Alfetta GTV
Alfa MY2004 147 TI
Alfa MY19 Giulia Veloce

Alfapride

  • Sr. Member
  • ****
  • Posts: 394
Re: Alfetta gtv carb set up
« Reply #6 on: April 05, 2021, 02:46:17 PM »
Found the accelerator pump jet ...42mm so disappointed  bought these from an Alfa specialist who rebuilt them and all the specs look wrong - any instructions how to check the Venturi ? Looks like Iíll have to do one order and get it right!
Alfa 33 16v
Alfa 116 Giulietta
Alfa 116 Alfetta GTV
Alfa MY2004 147 TI
Alfa MY19 Giulia Veloce

carlo rossi

  • Hero Member
  • *****
  • Posts: 708
  • AROCA Member #: 8733
Re: Alfetta gtv carb set up
« Reply #7 on: April 06, 2021, 10:35:09 AM »
the chokes come out after you loosen the side grub screws
they should be 32mm but with those jets they maybe bigger
i find 34mm the best all round not worth 32 to 33 difference is not worth investment
current cars
red 83 gtv 2.0


previous cars
Red 76 1.2/1.5 alfasud ti
white 79 alfetta 2000
alfetta 74 1.8
escort Lotus twin cam
bikes
ducati 900 ss 1979
moto morini 3 1/2 sport 1975/6
Moto morini 3 1/2 valentini speciale 77 oh and a deltek rockhopper

Alfapride

  • Sr. Member
  • ****
  • Posts: 394
Re: Alfetta gtv carb set up
« Reply #8 on: April 06, 2021, 10:48:43 AM »
Thanks Carlo confirmed they are 32 chokes will stick with them based on your advice, will look to get the other bits and report back once all installed thanks for your help
Alfa 33 16v
Alfa 116 Giulietta
Alfa 116 Alfetta GTV
Alfa MY2004 147 TI
Alfa MY19 Giulia Veloce

Alfapride

  • Sr. Member
  • ****
  • Posts: 394
Re: Alfetta gtv carb set up
« Reply #9 on: April 17, 2021, 01:28:12 PM »
I go to dellorto uk Iíll assume they are 10548 cans
Youíll need the emulsions air correctors 210
Mains 152
Idle 58
Accelerator pump jet 38 x4

Thanks Carlo I have put in the 58 idle jets and 38 pumps and matched all the emulsion tubes to .8 waiting on a manometer to tune properly but seems to be good so far - matching the emulsion tubes appears to have made a big improvement to hot starts - easy to start now before always struggled
Alfa 33 16v
Alfa 116 Giulietta
Alfa 116 Alfetta GTV
Alfa MY2004 147 TI
Alfa MY19 Giulia Veloce

Colin Edwards

  • Hero Member
  • *****
  • Posts: 674
  • AROCA Member #: 5065
Re: Alfetta gtv carb set up
« Reply #10 on: April 19, 2021, 08:12:49 AM »
Dropping down to 58 idle jets from the 62 resulting in leaner idle and progression will have helped hot starting.  Emulsion tubes should only enter the equation when the mains come on line. 
Present
2020 Giulietta Veloce
2018 Abarth 124 Spider
1987 75 3.0

Past
2015 Giulietta QV
2009 159 3.2 Ti Q4
2012 Giulietta TCT Veloce
2006 147 Ti 2 door Selespeed
1979 Alfasud Ti 1.5

carlo rossi

  • Hero Member
  • *****
  • Posts: 708
  • AROCA Member #: 8733
Re: Alfetta gtv carb set up
« Reply #11 on: May 03, 2021, 01:51:06 PM »
now thats all sorted warm the engine up  then screw in all all 4 idle mixture screws all the way in and turn them out around 3.5 turns ( should be lean)
and then increase the idle to around 1200rpm using the idle screw
turn all 4idles  anticlockwise half a turn
did the engine revs rise or drop
if it raised do this again if it drop turn clock wise 1 turn ( halfa turn from start point )
keep doing this until max revs are acheived then turn 1/4 turn anticlockwise to finish
this is to keep temps down

current cars
red 83 gtv 2.0


previous cars
Red 76 1.2/1.5 alfasud ti
white 79 alfetta 2000
alfetta 74 1.8
escort Lotus twin cam
bikes
ducati 900 ss 1979
moto morini 3 1/2 sport 1975/6
Moto morini 3 1/2 valentini speciale 77 oh and a deltek rockhopper

Alfapride

  • Sr. Member
  • ****
  • Posts: 394
Re: Alfetta gtv carb set up
« Reply #12 on: May 03, 2021, 10:45:46 PM »
Thanks Carlo rpm raise the more you richen the mixture I played around with them and one carb circa 8 turns and the other is 7 i reset the idle to 900 post the mixture adjustment seems to run pretty good now wonder if itís worth experimenting with 60 idle jets and 40 accelerator pumps or leave as is - I also have the 152 mains but still have the 148 I hadnít changed them over yet
Alfa 33 16v
Alfa 116 Giulietta
Alfa 116 Alfetta GTV
Alfa MY2004 147 TI
Alfa MY19 Giulia Veloce

Craig_m67

  • Hero Member
  • *****
  • Posts: 1128
Re: Alfetta gtv carb set up
« Reply #13 on: May 04, 2021, 08:30:34 AM »
Quick trip to Bunnings/Aldi and you can make your own manometer
(Worked perfectly)

'66 Duetto (lacework of doom)
'73 1600 GT Junior (ensconced)
'03 156 1.9JTD Sportwagon (daily driver)

Alfapride

  • Sr. Member
  • ****
  • Posts: 394
Re: Alfetta gtv carb set up
« Reply #14 on: May 05, 2021, 04:24:24 AM »
Cheers Craig I do have a manometer certainly helps with the balancing and tuning but great suggestion love the DIY!
Alfa 33 16v
Alfa 116 Giulietta
Alfa 116 Alfetta GTV
Alfa MY2004 147 TI
Alfa MY19 Giulia Veloce