I have one question that I just cant seam to find the answer to from anyone, everything Ive found provides indirect and sketchy answers so if someone can please just answer me this would be awesome. I have Dellorto 45 carbs that I plan on running on a 16v motor in my mk2 jetta and I will be running the oem fuel pump. So far I have: Carbs, manifold, fuel pressure regulator, oem IMC and a basic harness made to run it with a vacuum advanced dizzy however Im still missing a saab dizzy. So my question is can I just run it with what I have just basic and mechanical, with out all the MSD stuff?? And the saab distributor that I need to get is it off of a turbo or non turbo car?? Thanks in advance
FAQ - Carbs
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Hopfully have everything to go to carbs..
Been doing allot of reading and hope I now have everything to do my swap..
Going to the R1 carbs on my 91 16v 2.0 9a..
Going with the Carter pump with the Holley bypass fpr, for ignition I have the CB Performance "Black Box" going to use the stock distributor and coil, manifold is tapped for vacuum. That's the major stuff, going to go with aftermarket tach and the Black Box has wiring for that, btw, this will be in my 82 caddy. Doing mechanical oil,alt and temp gauges in the center console.
I'm not getting in a hurry doing a mild "freshing" of the 16v before the install as well as all new external items, water pump,ect.. Head will be port matched with Techtonics 268 cams. 5 spd tranny, should be a fun little ride!!!
Any tips on a clutch kit, would like to go with a Stage 2 but I'm sure a stock would be just fine..places to buy??
Been doing allot of reading and hope I now have everything to do my swap..
Going to the R1 carbs on my 91 16v 2.0 9a..
Going with the Carter pump with the Holley bypass fpr, for ignition I have the CB Performance "Black Box" going to use the stock distributor and coil, manifold is tapped for vacuum. That's the major stuff, going to go with aftermarket tach and the Black Box has wiring for that, btw, this will be in my 82 caddy. Doing mechanical oil,alt and temp gauges in the center console.
I'm not getting in a hurry doing a mild "freshing" of the 16v before the install as well as all new external items, water pump,ect.. Head will be port matched with Techtonics 268 cams. 5 spd tranny, should be a fun little ride!!!
Any tips on a clutch kit, would like to go with a Stage 2 but I'm sure a stock would be just fine..places to buy??
Joined
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12 Posts
1.8 GU 8v twin DCOE 40s
Weber DCOE experts please; I'm trying to jet my carbs so suggestions. I hope this helps others as it is very difficult to find anything on 8 valves with effect on drivability/performance. Here's my progress/trial and error write-up:-
Car is 1989 1.8GL UK right hand drive (brake servo in the way of cylinder 1 intake).
Facet 60104 fuel pump (inherited, not by choice).
Malpassi 3-way fuel regulator with return, guage set to 1.5psi, reasonably steady control.
Mangoletsi manifold, ported/port matched.
Massively ported GU head with old inlet manifold coolant feed blocked off. Exhaust/inlet on same side (rear of engine).
Standard valves, springs, hydraulic lifters, seats standard (throats have been widened/blended).
Camshaft is Newman 272 duration, 10.8mm? lift
Timing/ignition is standard GU distributor, vac advance connected to cyl 4 on Mangoletsi manifold with big green ball (from Pierburg 2E2) as vac pulse compensator.
Timing set to standard flywheel mark with vac disconnected from distributor at idle (is 18 degrees BTDC?).
Twin DCOE 40s only identification on them is '3K', possibly Toyota? They have 3 progression holes and originally had 30mm chokes.
Jetting:-
My starting point, more or less book guide values.
Chokes: 34mm
Mains: 135
Air Correctors: 185 (i.e, + 50 over mains)
Idles: 50 F9
Pump Jets (in carb already) : 35 (small?).
Emulsions: F16
What did it drive like? Very jerky on acceleration, almost like random missfire very scarey. Setting the idle screws, they were only 0.75 turns out (rich?).
Problems arise on transition about 2500rpm. Then no power and quiet running after 3000rpm, at wide open throttle to 4000rpm, too scared to go beyond 4000rpm. Otherwise was a pleasant drive around town.
I assumed the idle jets were too rich and the mains were way too lean. I already had some 180 air correctors from the old carb setup. I plonked these in to see if it helped richen the main circuit. The difference was barely noticable, but did make some small improvement (less jerking/missfire/smoother).
Next step I tried was 145 mains, I bought 125s as backup in case I was wrong too
. This made a drastic change to the whole setup especially at 3000-5000rpm where there was noticably more power, yay! However, drivability low down took a nose dive (stalling) and there was still alot of bucking/jerking.
Next I had already some 45 F8s from the old carb setup so swapped these in. Significant smoother town driving, however is still jerky at slow throttle transitioning to wide open throttle. No noticable difference from 3000-5000rpm. Wide open throttle sounds lean to me as in there isn't a roar of power, more like the sound of drawing air. Idle screws now set about 1 full turn out on each barrel. The 45 F8 has a massive air hole versus the 50 F9 so is leaner.
Current Jetting:-
Chokes: 34mm
Mains: 145
Air Correctors: 180
Idles: 45 F8
Pump Jets (in carb already) : 35 (small?).
Emulsions: F16
Guys, what is my next move? Here is my personal jet 'arsenal' to play with:-
Chokes: 30, 34
Emulsions: F16
Idles: 50 F9, 45 F8
Mains: 115, 125, 135, 145
Airs: 180, 185, 200
Pump Jets: 35
My gut feeling is that the mains can go richer still. +10 on the mains improved alot of the mid-range/top end. I ordered in some 160 air correctors, but some div sent me 1x160 and 3 x 100s, I could get a set of drill-bits I suppose and solder? Save me buying more jets.
Is it worth up-sizing the pump jets? These are more expensive parts.
Weber DCOE experts please; I'm trying to jet my carbs so suggestions. I hope this helps others as it is very difficult to find anything on 8 valves with effect on drivability/performance. Here's my progress/trial and error write-up:-
Car is 1989 1.8GL UK right hand drive (brake servo in the way of cylinder 1 intake).
Facet 60104 fuel pump (inherited, not by choice).
Malpassi 3-way fuel regulator with return, guage set to 1.5psi, reasonably steady control.
Mangoletsi manifold, ported/port matched.
Massively ported GU head with old inlet manifold coolant feed blocked off. Exhaust/inlet on same side (rear of engine).
Standard valves, springs, hydraulic lifters, seats standard (throats have been widened/blended).
Camshaft is Newman 272 duration, 10.8mm? lift
Timing/ignition is standard GU distributor, vac advance connected to cyl 4 on Mangoletsi manifold with big green ball (from Pierburg 2E2) as vac pulse compensator.
Timing set to standard flywheel mark with vac disconnected from distributor at idle (is 18 degrees BTDC?).
Twin DCOE 40s only identification on them is '3K', possibly Toyota? They have 3 progression holes and originally had 30mm chokes.
Jetting:-
My starting point, more or less book guide values.
Chokes: 34mm
Mains: 135
Air Correctors: 185 (i.e, + 50 over mains)
Idles: 50 F9
Pump Jets (in carb already) : 35 (small?).
Emulsions: F16
What did it drive like? Very jerky on acceleration, almost like random missfire very scarey. Setting the idle screws, they were only 0.75 turns out (rich?).
Problems arise on transition about 2500rpm. Then no power and quiet running after 3000rpm, at wide open throttle to 4000rpm, too scared to go beyond 4000rpm. Otherwise was a pleasant drive around town.
I assumed the idle jets were too rich and the mains were way too lean. I already had some 180 air correctors from the old carb setup. I plonked these in to see if it helped richen the main circuit. The difference was barely noticable, but did make some small improvement (less jerking/missfire/smoother).
Next step I tried was 145 mains, I bought 125s as backup in case I was wrong too
. This made a drastic change to the whole setup especially at 3000-5000rpm where there was noticably more power, yay! However, drivability low down took a nose dive (stalling) and there was still alot of bucking/jerking.Next I had already some 45 F8s from the old carb setup so swapped these in. Significant smoother town driving, however is still jerky at slow throttle transitioning to wide open throttle. No noticable difference from 3000-5000rpm. Wide open throttle sounds lean to me as in there isn't a roar of power, more like the sound of drawing air. Idle screws now set about 1 full turn out on each barrel. The 45 F8 has a massive air hole versus the 50 F9 so is leaner.
Current Jetting:-
Chokes: 34mm
Mains: 145
Air Correctors: 180
Idles: 45 F8
Pump Jets (in carb already) : 35 (small?).
Emulsions: F16
Guys, what is my next move? Here is my personal jet 'arsenal' to play with:-
Chokes: 30, 34
Emulsions: F16
Idles: 50 F9, 45 F8
Mains: 115, 125, 135, 145
Airs: 180, 185, 200
Pump Jets: 35
My gut feeling is that the mains can go richer still. +10 on the mains improved alot of the mid-range/top end. I ordered in some 160 air correctors, but some div sent me 1x160 and 3 x 100s, I could get a set of drill-bits I suppose and solder? Save me buying more jets.
Is it worth up-sizing the pump jets? These are more expensive parts.
Joined
·
715 Posts
I have a similar setup and will look at my notes of my current jetting and such but just a couple things off the bat... I had a facet pump and I had nothing but problems. Fuel pressure should be set at about 4 psi. And what do the plugs look like?
Joined
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12 Posts
Will try 4psi thanks. I moved to the Malpassi regulator as the Sytec Pro-Flow (with a dial) pressure was all over the place, especially as my suspension is pretty solid.
If you can find out your jetting setup that would be awesome! It will give me some grounding as to which way to head.
I think the pulsations of the Facet pump/rocking of 4 pot engine play havoc on the fuel level in the carbs, to the point that you end up with the "bucking" I'm getting. Just a theory. Will look for a "volume" pump.
If you can find out your jetting setup that would be awesome! It will give me some grounding as to which way to head.
I think the pulsations of the Facet pump/rocking of 4 pot engine play havoc on the fuel level in the carbs, to the point that you end up with the "bucking" I'm getting. Just a theory. Will look for a "volume" pump.
Joined
·
12 Posts
Tried 4psi, not any real noticable difference.
Took out the plugs, they are as black as night, not wet, just a coating of dry soot. Too rich then, where next?
Took out the plugs, they are as black as night, not wet, just a coating of dry soot. Too rich then, where next?
Joined
·
12 Posts
All four spark plugs look like this
Joined
·
12 Posts
The old Pierburg carb took the vacuum where I have it taken from, just now its a single port so no smooth VAC signal. The old manifold had a tube with a tiny hole in it, using this might help to smooth out the pressure variations? Or add VAC pipes on the trumpets? Think this would be wrong anyway, great for checking balance tho.
Could try moving the timing about, if so what am I looking for as regards noises to avoid
(pinking). Want me to post the timing at each rpm I'm currently getting?
Joined
·
12 Posts
Ok SHES ALIVE!
Finally bit the bullet and removed the brake servo to make way for trumpet #1. Saw a few guys running without them and figured the breaks couldn't get that much worse...ok they do, you don't appreciate the extra effort from it until its gone. Practically had to remove the whole front subframe to tilt the engine far enough forward to get the servo outta there.
However, what a monster, and the sound too! 3000rpm to 4000 is rapid, I used to have a Lotus esprit S3, about 160 bhp? Must be near to that easily. Feels like it runs out of puff about 4500rpm, so maybe richer mains...currently at 145 and airs are at 200.
It was the foam filter. Blocking #1 when at full throttle with the venturi jiggling around inside that barrel.
Finally bit the bullet and removed the brake servo to make way for trumpet #1. Saw a few guys running without them and figured the breaks couldn't get that much worse...ok they do, you don't appreciate the extra effort from it until its gone
. Practically had to remove the whole front subframe to tilt the engine far enough forward to get the servo outta there.However, what a monster, and the sound too! 3000rpm to 4000 is rapid, I used to have a Lotus esprit S3, about 160 bhp? Must be near to that easily. Feels like it runs out of puff about 4500rpm, so maybe richer mains...currently at 145 and airs are at 200.
It was the foam filter. Blocking #1 when at full throttle with the venturi jiggling around inside that barrel.
I'm using a Daytona Sensors TCS-1 instead of a MSD 8980 or 8982. I modified BigCaddy's diagram to reflect my setup. I also included the timing parameters and timing table I'm using. I just got the car running so I'm not positive this is the best timing curve. Car is an 82 Scirocco with a 9A on twin dellorto DHLA 45's. Fueling taken care of by a Carter 4070 fuel pump with Malpassi regulator. (Still trying to get the fuel pump relay to work. 6AL is driving tach just fine but not fuel pump relay, waiting on a NOS relay vice the 20$ aftermarket version available right now.
Chokes - 37
Idle Jet Holder - 7850.2
Idle Jet - 55
Air Corrector Jet - 195
Emulsion Tube - 7772.5
Main Jet - 145
Pump Jet - 40
Needle Valve - 2.00
Car is running good but leans out under heavy acceleration. Going to bump up the main jets. Also a tad rich at idle and mixture screws are only open 1 5/8 turns, going to bump down on the idle jets
Chokes - 37
Idle Jet Holder - 7850.2
Idle Jet - 55
Air Corrector Jet - 195
Emulsion Tube - 7772.5
Main Jet - 145
Pump Jet - 40
Needle Valve - 2.00
Car is running good but leans out under heavy acceleration. Going to bump up the main jets. Also a tad rich at idle and mixture screws are only open 1 5/8 turns, going to bump down on the idle jets
Please don't chastise me for this but after reading 15 pages of this post i have found a plethora of very useful information, but not the answers I'm looking for.
1. When carb - ing, what does one do about MAF sensor? Is the only way to run some form of stand alone engine management?
2. What is done about PCV and crank case breathing? My current engine came to me with one of those little filters in place of PCV, and an oil leak from the base of the distributor. When i reinstalled a factory PCV plumbed to intake, the oil leak stopped permanently.
I have been gathering parts for about a year to swap my ABA hybrid from an mk2 gti into an mk1 cabby, what I've realized is there is not enough space for the stock passenger side airbox. Only ideas ihave at this point are build a different head or carb/itb the one I've already got...
Suggestions?
Thank you
1. When carb - ing, what does one do about MAF sensor? Is the only way to run some form of stand alone engine management?
2. What is done about PCV and crank case breathing? My current engine came to me with one of those little filters in place of PCV, and an oil leak from the base of the distributor. When i reinstalled a factory PCV plumbed to intake, the oil leak stopped permanently.
I have been gathering parts for about a year to swap my ABA hybrid from an mk2 gti into an mk1 cabby, what I've realized is there is not enough space for the stock passenger side airbox. Only ideas ihave at this point are build a different head or carb/itb the one I've already got...
Suggestions?
Thank you
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