Dual carbs for a 2.0, A few questions |
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Dual carbs for a 2.0, A few questions |
flipb |
May 18 2010, 08:08 PM
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#1
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Senior Member Group: Members Posts: 1,722 Joined: 2-September 09 From: Fairfax, VA Member No.: 10,752 Region Association: MidAtlantic Region |
I bought my '74 2.0 with a Weber progressive carb. It's in my plans to switch to dual carbs, probably next fall/winter.
I don't know for certain but I suspect that the Cam is for carbs, not stock. From what I've gathered, 40mm carbs are the right size for a 2.0 motor for street use. Right? I get the feeling that my top choices, in order, are: Dellorto 40mm Weber IDF (Italian-made) 40mm Others? EMPI (modern version of Weber)? Solex? I'm curious to other's input on what to look for and what to avoid. Final question: If I buy a complete setup from classifieds on thesamba, will it fit a 914 2.0? (Intakes and all) Since I've already got the single carb, I presume my low-pressure fuel pump will be appropriate with duals as well... |
Chris Hamilton |
May 18 2010, 08:32 PM
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#2
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Senior Member Group: Members Posts: 611 Joined: 7-March 06 From: Berkeley, CA Member No.: 5,687 |
I think the best advice would be to find a mechanic you trust who really knows carbs inside and out. A bit of tuning and adjustment will probably be needed and will make the difference between a smooth sweet drive and a serious headache.
40mm dellortos or webers will really run great as long as they are properly installed and tuned. If your car has 2.0 heads you'll want to look for either the manifolds with a single bolt hole in the middle or the universal ones with bolt holes for a 1.8 or 2.0. You will want to avoid the Dellorto carbs that are made for an Alfa. I bought a pair of those at one point and could never get them tuned properly, the dellortos made for VW will work great. |
scrz914 |
May 18 2010, 09:13 PM
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#3
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Member Group: Members Posts: 397 Joined: 21-April 04 From: Santa Cruz, CA Member No.: 1,960 Region Association: Central California |
(IMG:style_emoticons/default/hijacked.gif) Italian Webers were mentioned. How can you tell if they are Italian or other? I have some that just say Weber but no "MADE IN..."
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jmill |
May 18 2010, 09:14 PM
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#4
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Green Hornet Group: Members Posts: 2,449 Joined: 9-May 08 From: Racine, Wisconsin Member No.: 9,038 Region Association: Upper MidWest |
I doubt you have a carb cam. A guy who spends the time and money to split the case to add a carb cam isn't going to bolt on a progressive.
If you like wrenching you can go the hard way but learn a lot. Buy a used set and rebuild them. Expect to spend time tweaking your vent and jet combo. Also expect to change your cam to reap the rewards of the duals. I like Weber IDFs. Just a personal thing. I have no experience with Dells. If you have the money buy the carbs and cam kit from Jake. You'll definately be time ahead. You might even be money ahead because you'll get it right the first time. |
flipb |
May 19 2010, 06:59 AM
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#5
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Senior Member Group: Members Posts: 1,722 Joined: 2-September 09 From: Fairfax, VA Member No.: 10,752 Region Association: MidAtlantic Region |
The PO believed there had been an engine rebuild at the same time as the switch from FI to carbs (probably also when the fuel pump was relocated to the front). Plus, it runs really well on the Progressive carb, except in cold temps. That's why I suspect it's got a carb cam.
Odometer doesn't work but it's supposedly a 130K mile car and drives great. |
IronHillRestorations |
May 19 2010, 07:01 AM
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#6
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I. I. R. C. Group: Members Posts: 6,719 Joined: 18-March 03 From: West TN Member No.: 439 Region Association: None |
Flip, if you can swing it buy new carbs from a reputable dealer that knows flat fours.
Bigger is NOT better! Optimized for your engine is better. 40's with 36 venturis will probably suit your engine fine. More than likely John is right, it's doubtfull your engine has a different cam, unless the seller pulled the dual carbs off before selling it to you. You also need to check out your distributor and make sure you've got one that with a good advance curve for a 914 engine. There's a ton of Bosch 009's out there and they will work, but aren't the best for a 914. Do a search on this website and you'll find some good info. |
gothspeed |
May 19 2010, 07:06 AM
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#7
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Senior Member Group: Members Posts: 1,539 Joined: 3-February 09 From: SoCal Member No.: 10,019 Region Association: None |
This is all great info! (IMG:style_emoticons/default/smile.gif)
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flipb |
May 19 2010, 07:38 AM
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#8
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Senior Member Group: Members Posts: 1,722 Joined: 2-September 09 From: Fairfax, VA Member No.: 10,752 Region Association: MidAtlantic Region |
You also need to check out your distributor and make sure you've got one that with a good advance curve for a 914 engine. There's a ton of Bosch 009's out there and they will work, but aren't the best for a 914. Do a search on this website and you'll find some good info. I've got a Pertronix ignition (also by the PO). My mechanic is a very good P-car guy, has a handful of TIV-engine clients, mostly air-cooled sixes, but definitely knows what he's doing. I was originally going to wait for Raby's new cable linkage and buy new EMPIs with the linkage from him... but I think he's stopped selling carb kits altogether, except as part of an engine kit. |
Root_Werks |
May 19 2010, 08:33 AM
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#9
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Village Idiot Group: Members Posts: 8,320 Joined: 25-May 04 From: About 5NM from Canada Member No.: 2,105 Region Association: Pacific Northwest |
I have the 40IDF's on my 2.0 and so far, like them. I haven't gone into them much yet, but looks like they are running 125's for the mains. Haven't looked to see what idle's or vent size the carbs are running. I'm pretty sure I have a FI cam.
I also have a 009 Dist, if you have one, toss it. Go find a dist from a FI 1.8 or use a VW 034 with vac adv and hook it up. It'll be much smoother driving around town. So to further support Flip's question, say he gets a set of 40IDF. What is the best combo for mains, idles and vent's to run with a stock 2.0 set-up? 125 mains 60-65 idles? I was thinking 32 vents? (IMG:style_emoticons/default/confused24.gif) |
gothspeed |
May 19 2010, 09:30 AM
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#10
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Senior Member Group: Members Posts: 1,539 Joined: 3-February 09 From: SoCal Member No.: 10,019 Region Association: None |
I have the 40IDF's on my 2.0 and so far, like them. I haven't gone into them much yet, but looks like they are running 125's for the mains. Haven't looked to see what idle's or vent size the carbs are running. I'm pretty sure I have a FI cam. I also have a 009 Dist, if you have one, toss it. Go find a dist from a FI 1.8 or use a VW 034 with vac adv and hook it up. It'll be much smoother driving around town. So to further support Flip's question, say he gets a set of 40IDF. What is the best combo for mains, idles and vent's to run with a stock 2.0 set-up? 125 mains 60-65 idles? I was thinking 32 vents? (IMG:style_emoticons/default/confused24.gif) http://www.hot-spark.com/Hot-Spark-SVDA-034-BOS4V1.htm I am considering dual webers on my 2056 but need to find out if what I will be needing is available (IMG:style_emoticons/default/smile.gif) |
Root_Werks |
May 19 2010, 09:40 AM
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#11
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Village Idiot Group: Members Posts: 8,320 Joined: 25-May 04 From: About 5NM from Canada Member No.: 2,105 Region Association: Pacific Northwest |
I have the 40IDF's on my 2.0 and so far, like them. I haven't gone into them much yet, but looks like they are running 125's for the mains. Haven't looked to see what idle's or vent size the carbs are running. I'm pretty sure I have a FI cam. I also have a 009 Dist, if you have one, toss it. Go find a dist from a FI 1.8 or use a VW 034 with vac adv and hook it up. It'll be much smoother driving around town. So to further support Flip's question, say he gets a set of 40IDF. What is the best combo for mains, idles and vent's to run with a stock 2.0 set-up? 125 mains 60-65 idles? I was thinking 32 vents? (IMG:style_emoticons/default/confused24.gif) http://www.hot-spark.com/Hot-Spark-SVDA-034-BOS4V1.htm I am considering dual webers on my 2056 but need to find out if what I will be needing is available (IMG:style_emoticons/default/smile.gif) Yup! Probably not quite as good as a german T205??? I think is what they are called? I think the advance curve is a little less agressive than the 1.8 914 FI Dizzy, but I've read lots of threads from the samba and even a couple of 914 guys who have said the 034 works great. 10,000 times better than any 009. I'm hoping to pick up my 1.8 Dizzy Friday and install it, toss my 009. If I couldn't find a 1.8 dizzy, I would be buying a 034. I've actually heard that 009's were originally made for track applications. Pretty much were you had a set total advance and didn't care how the engine performed under 3500rpms. Somewhere along the way, the general public noticed "Racing dist" and associated it with going fast on a street car? Not sure, but for decades it was known as "THE" dizzy to have on air cooled 4cyl's. |
Root_Werks |
May 19 2010, 09:46 AM
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#12
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Village Idiot Group: Members Posts: 8,320 Joined: 25-May 04 From: About 5NM from Canada Member No.: 2,105 Region Association: Pacific Northwest |
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gothspeed |
May 19 2010, 10:19 AM
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#13
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Senior Member Group: Members Posts: 1,539 Joined: 3-February 09 From: SoCal Member No.: 10,019 Region Association: None |
So in your opinion what is the diz for dual webers on a 2056 and a hot cam.
Put these in order of how well you think they will work: 034 010 050 1.8 and any others you can think of thanks for the info, that thread was helpful! I have the 40IDF's on my 2.0 and so far, like them. I haven't gone into them much yet, but looks like they are running 125's for the mains. Haven't looked to see what idle's or vent size the carbs are running. I'm pretty sure I have a FI cam. I also have a 009 Dist, if you have one, toss it. Go find a dist from a FI 1.8 or use a VW 034 with vac adv and hook it up. It'll be much smoother driving around town. So to further support Flip's question, say he gets a set of 40IDF. What is the best combo for mains, idles and vent's to run with a stock 2.0 set-up? 125 mains 60-65 idles? I was thinking 32 vents? (IMG:style_emoticons/default/confused24.gif) http://www.hot-spark.com/Hot-Spark-SVDA-034-BOS4V1.htm I am considering dual webers on my 2056 but need to find out if what I will be needing is available (IMG:style_emoticons/default/smile.gif) Yup! Probably not quite as good as a german T205??? I think is what they are called? I think the advance curve is a little less agressive than the 1.8 914 FI Dizzy, but I've read lots of threads from the samba and even a couple of 914 guys who have said the 034 works great. 10,000 times better than any 009. I'm hoping to pick up my 1.8 Dizzy Friday and install it, toss my 009. If I couldn't find a 1.8 dizzy, I would be buying a 034. I've actually heard that 009's were originally made for track applications. Pretty much were you had a set total advance and didn't care how the engine performed under 3500rpms. Somewhere along the way, the general public noticed "Racing dist" and associated it with going fast on a street car? Not sure, but for decades it was known as "THE" dizzy to have on air cooled 4cyl's. |
Root_Werks |
May 19 2010, 10:39 AM
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#14
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Village Idiot Group: Members Posts: 8,320 Joined: 25-May 04 From: About 5NM from Canada Member No.: 2,105 Region Association: Pacific Northwest |
Well, everyone has an opinion and I'm sure someone will dissagree with me, but I would put them in this order:
1.8 - Stock FI dizzy that doesn't have the FI trigger points like D-Jet does 034 - Stock VW dizzy that has a good curve and works very well 010 - Not a vac adv dizzy, from early 912's I believe, but work well 050 - Also not a vac adv dizzy, but I've had one before and others like them. The 010 and 050 are both good, but I think for something driven daily or normally, you almost need the vac adv option. Otherwise you'll never get the proper advance when just puttering around town. (IMG:style_emoticons/default/driving.gif) |
IronHillRestorations |
May 19 2010, 11:10 AM
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#15
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I. I. R. C. Group: Members Posts: 6,719 Joined: 18-March 03 From: West TN Member No.: 439 Region Association: None |
I heard the 009 was made for industrial engines, but I too have a ton of problem free miles in a carb'd 914 with a 009.
I'm with pretty much with Root on the distributor assessment, but I've also heard the 1.8 distributor with the vacuum hooked up is hard to beat. IIRC the vacuum dashpot adds retard at idle, so the vacuum signal has to be done correctly. |
gothspeed |
May 19 2010, 11:19 AM
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#16
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Senior Member Group: Members Posts: 1,539 Joined: 3-February 09 From: SoCal Member No.: 10,019 Region Association: None |
Fantastic info guys (IMG:style_emoticons/default/smile.gif). I usually set timming at full advance, with vacuum/boost disconnected at high RPM (at least that is how my old 930 was done). Of course that may differ for any given motor/use configuration.
Does anyone know at what RPM should these 914 engines see maximum advance? |
Root_Werks |
May 19 2010, 01:26 PM
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#17
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Village Idiot Group: Members Posts: 8,320 Joined: 25-May 04 From: About 5NM from Canada Member No.: 2,105 Region Association: Pacific Northwest |
Fantastic info guys (IMG:style_emoticons/default/smile.gif). I usually set timming at full advance, with vacuum/boost disconnected at high RPM (at least that is how my old 930 was done). Of course that may differ for any given motor/use configuration. Does anyone know at what RPM should these 914 engines see maximum advance? Someone can correct me if I'm wrong, but I do believe all the dizzy's listed will reach full advance anything over 3700rpm's. So just bring it to 4k on the tach and you should be good. Were's the timing light smiley? (IMG:style_emoticons/default/biggrin.gif) |
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