Single carburetor setup, Setup single carburetor/distributor for a 1.8 |
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
Single carburetor setup, Setup single carburetor/distributor for a 1.8 |
cmxiv 74 |
Aug 10 2017, 02:04 AM
Post
#1
|
Newbie Group: Members Posts: 11 Joined: 9-August 17 From: Los Angeles Member No.: 21,334 Region Association: Southern California |
Hi, I need to know if anyone around has a functional, decent (not performance, not perfect) setup that involves a center mounted carburetor on a 1.8 L engine. While I'm new to the subject I'm well aware about the inefficiency of the center mounted single carburetor setup on 914. Yes, it sucks ! But I have to deal with the facts and the reality. This are the facts: I bought my 74 1.8 already converted on single carburetor, (looks like a Weber, made in Spain, no other markings visible without removal) paired with a centrifugal advance distributor (not sure what model, no markings visible without removal) not know when was converted, or if the engine is stock or not. While has a decent acceleration response, decent power it runs very bad, inconsistent warm startup, high idle, rich, overall I can't find a "sweet spot". So far I changed the points, condenser, wires, spark plus, spark wires, distributor cap and rotor. The car is in what I call "active" repair/restoration which means that I have to keep it running and do work on it whenever I have the time and a place to work on it. So far is in my friends shop but while I will continue to have shop access I can not keep it there anymore, so it has to be parked on the street (it is registered and insured). For now I have to keep the car running with a single carburetor, so any other option is out.
Now... not sure if the centrifugal distributor is a good idea for this already bad setup, but I need opinion and advice from people who know how to do a proper setup for a single carb. I will add more info and photos over the next days Thank You ! PS. It looks like I have a 1.7 L not 1.8.The engine serial nr starts with EA, assigned to a 1973 1.7 L. Attached thumbnail(s) |
VaccaRabite |
Aug 10 2017, 07:59 AM
Post
#2
|
En Garde! Group: Admin Posts: 13,553 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
You may find people that have gotten single carbs to run, but you wont find many that have gotten them to run well. The problems you have stated are very very common with single carb set ups. they just don't work all that well becasue the fuel start to fall out of suspension before it hits the intake valve.
T1 engines got around this by running exhaust gasses up along the intake runners from the single carb to keep them warm and keep the fuel in suspension that way. 914s can't do that. Well, not easily. Spend a little bit of money to get a dual carb setup, and you will be very happy that you did. Your car will run much better, and you will get more power out of your 1.7. Zach |
GeorgeRud |
Aug 10 2017, 08:49 AM
Post
#3
|
Advanced Member Group: Members Posts: 3,725 Joined: 27-July 05 From: Chicagoland Member No.: 4,482 Region Association: Upper MidWest |
If you search around, you may be able to find a dual carb setup used for sale. Since the car is already running a carb, it should be an easy Saturday project to convert it to dual carbs and enjoy much better running.
A more expensive option would be conversion to EFI, but that would be a much bigger project. |
Spoke |
Aug 10 2017, 09:01 AM
Post
#4
|
Jerry Group: Members Posts: 7,052 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None |
(IMG:style_emoticons/default/welcome.png)
Sounds like your carb/distributor setup is working ok. Personally I wouldn't put any money into a 1.7/1.8L engine. Besides a turbo or supercharger, the 1.7/1.8L will still be a low HP engine. I've had 914's with a 1.7L (dual carbs), 1.8L (DJET FI), 2L (DJET), and 2056 (dual carbs). The 2L and 2056 nearly transform the car from the 1.7/1.8 engines. Look around for someone doing a /6 or Suby conversion and dumping their 2L. I picked up my 2056 with dual carbs for less than $1k shipped. Remember there's no replacement for displacement. |
bbrock |
Aug 10 2017, 10:34 AM
Post
#5
|
914 Guru Group: Members Posts: 5,269 Joined: 17-February 17 From: Montana Member No.: 20,845 Region Association: Rocky Mountains |
Long, long ago, I tried a single carb on both a 1.7L 914 and a VW bus. I never could get it to run properly. The problem was those intake runners that others have mention. So no dizzy swap was going to help. I finally swapped them for a pair of 34 ICTs which could be bought for very cheap back then. They still sucked for performance, but at least the cars were drivable.
|
914_teener |
Aug 10 2017, 10:51 AM
Post
#6
|
914 Guru Group: Members Posts: 5,245 Joined: 31-August 08 From: So. Cal Member No.: 9,489 Region Association: Southern California |
So you need an expert on a setup that sucks?
|
struckn |
Aug 10 2017, 12:39 PM
Post
#7
|
Senior Member Group: Members Posts: 1,069 Joined: 9-November 11 From: South Central York Pennsyvania Member No.: 13,764 Region Association: MidAtlantic Region |
Here's my '74 with same set up. If tuned correctly and float adjusted right it isn't a bad set up. Only thing you must be aware of is that the Cam should be for carb not Fuel Injection. FI was the way they came when new. Also I think this is the only set up that has Electric Choke to help with satrating, and these are quiter then dual carb, The fuel mileage is better too.
https://youtu.be/H4t0M2wrhu8 |
struckn |
Aug 10 2017, 12:51 PM
Post
#8
|
Senior Member Group: Members Posts: 1,069 Joined: 9-November 11 From: South Central York Pennsyvania Member No.: 13,764 Region Association: MidAtlantic Region |
Here's my '74 with same set up. If tuned correctly and float adjusted right it isn't a bad set up. Only thing you must be aware of is that the Cam should be for carb not Fuel Injection. FI was the way they came when new. Click and WATCH MY YOU/TUBE below it tells the store. It's been 5 years since I made this video and I drive the car alot. Haven't had to adjust, tune or repair anything, still runs the same, no plans to change anything.
And to all you nay sayers (IMG:style_emoticons/default/bootyshake.gif) https://youtu.be/H4t0M2wrhu8 |
bandjoey |
Aug 10 2017, 01:34 PM
Post
#9
|
bandjoey Group: Members Posts: 4,930 Joined: 26-September 07 From: Bedford Tx Member No.: 8,156 Region Association: Southwest Region |
Find a hot rod shop and you'll find a carb guy. Ask the FLAPs guys too. And Post a WTB for dual carbs and you'll be ever so happy.
|
andys |
Aug 10 2017, 02:35 PM
Post
#10
|
Advanced Member Group: Members Posts: 2,165 Joined: 21-May 03 From: Valencia, CA Member No.: 721 Region Association: None |
Out of desperation, after my FI left me standing for the fourth time ('73 2.0, 40 years ago), I made up my own single carb setup. Ford/Holley single barrel carb on an adapter plate, and an electric fuel pump. It actually ran quite well; biggest relief was that it started every time with no worries whatsoever. I eventually went with a dual Weber setup which took A LOT OF WORK to get it jetted somewhat right. Not sure it ran better than the single, but it sure looked cool!
Andys |
Al Meredith |
Aug 10 2017, 02:57 PM
Post
#11
|
Senior Member Group: Members Posts: 967 Joined: 4-November 04 From: Atlanta, ga Member No.: 3,061 |
try two things: One, I remove the thick plastic intake gasket and replace it with a metal gasket. This way the heat from the head will transfer to the long runners and heat the intake charge. Second, replace the idle jet with a larger jet. The carb was probably jetted for a VW engine.
|
ndfrigi |
Aug 10 2017, 03:14 PM
Post
#12
|
Advanced Member Group: Members Posts: 2,953 Joined: 21-August 11 From: Orange County Member No.: 13,474 Region Association: Southern California |
I sold my friend's 73 1.7 yellow last 2015 thanksgiving day to an Ohio member (now my facebook friend), the car has #1 cylinder low compression with single weber carb. He and his wife drove it from SoCal to Vegas and all the way to Ohio for 2,500 miles trip within 5 days (i think) and with no issues.
|
bbrock |
Aug 10 2017, 03:30 PM
Post
#13
|
914 Guru Group: Members Posts: 5,269 Joined: 17-February 17 From: Montana Member No.: 20,845 Region Association: Rocky Mountains |
Long, long ago, I tried a single carb on both a 1.7L 914 and a VW bus. I never could get it to run properly. The problem was those intake runners that others have mention. So no dizzy swap was going to help. I finally swapped them for a pair of 34 ICTs which could be bought for very cheap back then. They still sucked for performance, but at least the cars were drivable. I should probably amend my previous post to say that the problems I had with my single carbs were associated with cold weather. Whenever the temps would dip below about 40F, the cars would just die. The runners would literally build up a cake of frost on them. When the weather was warm, they ran okay except for the dead spot caused by the 009 dizzy. I just noticed the OP is in LA so my experience with single carbs in a colder climate might not be so relevant. |
cmxiv 74 |
Aug 11 2017, 01:01 AM
Post
#14
|
Newbie Group: Members Posts: 11 Joined: 9-August 17 From: Los Angeles Member No.: 21,334 Region Association: Southern California |
Hi everyone, Thank you all for taking time and effort to make comments and for sharing your opinions. To make everything crystal clear please consider that my question/curiosities revolved around the existent setup on my car" center single carburetor", not about the common sense/better/ideal option (double carbs, injection or engine upgrades). I will eventually get there in the future, but not today or tomorrow. At the end of the day I would like to find a solution with the existing setup in place that will make sure the car can be started and driven (enjoyed) at least 100 miles/month for the next 6 months. The "to do list" on my car is pretty long, so due the "logistic reasons" I want to be sure that I can do as much as possible with the car in decent running condition before I will tune or replace the engine. Great/best performance, squeezing the last joule per second or a tiny fraction of HP from the engine or the mileage are not the issue right now.
So, not knowing who made the conversion back to the day (shop, garage, back yard) I have not clue if the came was swapped for the correct one (carburetor optimized) so I will presume was not. I will go to the shop over the weekend, pull out the carb and distributor, get all the info I can get from both parts and post it here to continue with fresh data. As a personal curiosity...Just asking... My setup, the single central carburetor conversion kit was available on the market decades ago, people used this option for various reasons, (well... one...it was the cheapest). So how, over the years the shops or mechanics got away with using this very setup since there are so unreliable, horrible, snake oil POS and junk ?, After all when the client took his car out of the shop after a conversion it's supposed to run decent, no? Clients usually do not pay to have their vehicle grossly downgraded and turned unreliable? To add to the confusion after so many years the "single" kits are still offered for sale ! Again, just asking... On a different note, just as info: Repairs I did myself: rebuild the brakes/calipers (not easy, not even close to any regular brake job repair due to the lack of documentation and the cumbersomeness of the design), (IMG:style_emoticons/default/welder.gif) fix the "imploded" clutch tunnel (a PITA, especially with limited welding shop tools) fixed the throttle cable tunnel, a huge array of electrical issue (including an preexisting hidden short that melted a bunch of wires under the dash, fire extinguisher required ), headlights, mechanical and electric, working from home on the upholstery (desert stored car... all the vinyl upholstery dead dried, crumbled, brittle and cracked), transmission shifter & linkage rebuild (I end up machining myself some Delrin bushing and metal sleeves... the aftermarket parts ordered were way beyond the specs... junk) |
cmxiv 74 |
Aug 11 2017, 01:07 AM
Post
#15
|
Newbie Group: Members Posts: 11 Joined: 9-August 17 From: Los Angeles Member No.: 21,334 Region Association: Southern California |
(IMG:style_emoticons/default/welcome.png) Sounds like your carb/distributor setup is working ok. Personally I wouldn't put any money into a 1.7/1.8L engine. Besides a turbo or supercharger, the 1.7/1.8L will still be a low HP engine. I've had 914's with a 1.7L (dual carbs), 1.8L (DJET FI), 2L (DJET), and 2056 (dual carbs). The 2L and 2056 nearly transform the car from the 1.7/1.8 engines. Look around for someone doing a /6 or Suby conversion and dumping their 2L. I picked up my 2056 with dual carbs for less than $1k shipped. Remember there's no replacement for displacement. Agree, I'm looking around to do something like that in the future, but not in a rush at all. So far just 1.8 on the market. |
cmxiv 74 |
Aug 11 2017, 01:18 AM
Post
#16
|
Newbie Group: Members Posts: 11 Joined: 9-August 17 From: Los Angeles Member No.: 21,334 Region Association: Southern California |
So you need an expert on a setup that sucks? Not an expert at all, they have no time for challenges or out of the box solution, I want just a fair opinion/advice from someone who drives a car with a similar setup, or had at one point a running setup like mine. |
cmxiv 74 |
Aug 11 2017, 01:29 AM
Post
#17
|
Newbie Group: Members Posts: 11 Joined: 9-August 17 From: Los Angeles Member No.: 21,334 Region Association: Southern California |
Here's my '74 with same set up. If tuned correctly and float adjusted right it isn't a bad set up. Only thing you must be aware of is that the Cam should be for carb not Fuel Injection. FI was the way they came when new. Also I think this is the only set up that has Electric Choke to help with satrating, and these are quiter then dual carb, The fuel mileage is better too. https://youtu.be/H4t0M2wrhu8 No clue about the cam and no clue how to have it check without a huge mess. The electric choke is there and functional, probably set for warm climate (So Cal). I'm familiar with the electric choke system from Type 1/Pict on Beetle and KarmanGhia. Regarding being quiet...Can't tell ... the exhaust/muffler is really loud, it might be some performance package, not sure , but I have to dig around to find out. Are you running a centrifugal advance distributor or vacuum ? If vacuum , where is connected ? Thank's |
cmxiv 74 |
Aug 11 2017, 01:38 AM
Post
#18
|
Newbie Group: Members Posts: 11 Joined: 9-August 17 From: Los Angeles Member No.: 21,334 Region Association: Southern California |
Out of desperation, after my FI left me standing for the fourth time ('73 2.0, 40 years ago), I made up my own single carb setup. Ford/Holley single barrel carb on an adapter plate, and an electric fuel pump. It actually ran quite well; biggest relief was that it started every time with no worries whatsoever. I eventually went with a dual Weber setup which took A LOT OF WORK to get it jetted somewhat right. Not sure it ran better than the single, but it sure looked cool! Andys Pretty cool, Where there's a need there's a solution. Your setup reminds me of running my 1300 '66 Beetle (back to Europe, some decades ago), with a borrowed carburetor from a 1310 cc 1984 Dacia (Romanian car based on 1969 Renault 12). Same displacement, totally different animal, same story, home made plate adapter...but it worked OK (most of the time) |
cmxiv 74 |
Aug 11 2017, 01:43 AM
Post
#19
|
Newbie Group: Members Posts: 11 Joined: 9-August 17 From: Los Angeles Member No.: 21,334 Region Association: Southern California |
try two things: One, I remove the thick plastic intake gasket and replace it with a metal gasket. This way the heat from the head will transfer to the long runners and heat the intake charge. Second, replace the idle jet with a larger jet. The carb was probably jetted for a VW engine. Thank you ! Noted, I will do that . I asked myself if will make any difference the direct heat transfer to the carb from the engine via the runners. I will check the idle jet , but not sure what to compare with , or if there is a optimal size / setup. There is a total lack of info on the subject, or maybe I can't fin it. |
cmxiv 74 |
Aug 11 2017, 01:53 AM
Post
#20
|
Newbie Group: Members Posts: 11 Joined: 9-August 17 From: Los Angeles Member No.: 21,334 Region Association: Southern California |
Long, long ago, I tried a single carb on both a 1.7L 914 and a VW bus. I never could get it to run properly. The problem was those intake runners that others have mention. So no dizzy swap was going to help. I finally swapped them for a pair of 34 ICTs which could be bought for very cheap back then. They still sucked for performance, but at least the cars were drivable. I should probably amend my previous post to say that the problems I had with my single carbs were associated with cold weather. Whenever the temps would dip below about 40F, the cars would just die. The runners would literally build up a cake of frost on them. When the weather was warm, they ran okay except for the dead spot caused by the 009 dizzy. I just noticed the OP is in LA so my experience with single carbs in a colder climate might not be so relevant. Decent original 34 ICT are hard to get, or to expensive to buy professionally rebuilt, it will cost almost as much as a dual full kit Correct, I have to be in the upper desert, in February to get around that kind of low temp, not a major issue for LA. I know about the ice build up from my 66 Beetle ages ago, It did iced in the summer, the heater exhaust runner was almost clogged |
Lo-Fi Version | Time is now: 26th September 2024 - 11:13 PM |
All rights reserved 914World.com © since 2002 |
914World.com is the fastest growing online 914 community! We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ... |