 Throwing in the towel, Carburator conversion for 74 1.8 ltr |
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| downrange |
 Jul 16 2019, 02:16 PM
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#1
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Newbie  Group: Members Posts: 22 Joined: 1-January 18 From: Pennsylvania Member No.: 21,747 Region Association: MidAtlantic Region  |
I am on my last nerve trying to get my 74 1.8 ltr L Jetronic fuel injected car started. Bypassed the seatbelt interlock to get the starter to work. Hot wired the fuel pump to get it working and still no go.
I am considering a carburetor conversion and see that Redline has a few kits. The dual carbs system has no choke and the single carb with electric choke has some distance from the cylinder heads. Anyone have any success they could share? |
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| SirAndy |
Jul 16 2019, 02:19 PM
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#2
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Resident German Group: Admin Posts: 41,602 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
Don't ...
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| yellowporky |
Jul 16 2019, 02:37 PM
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#3
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Member Group: Members Posts: 422 Joined: 18-October 09 From: Martinez, Ca. Member No.: 10,948 Region Association: Northern California |
2nd the don't
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| mepstein |
Jul 16 2019, 02:42 PM
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#4
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914-6 GT in waiting Group: Members Posts: 19,221 Joined: 19-September 09 From: Landenberg, PA/Wilmington, DE Member No.: 10,825 Region Association: MidAtlantic Region 
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QUOTE(yellowporky @ Jul 16 2019, 04:37 PM)  2nd the don't (IMG:style_emoticons/default/agree.gif) Where in PA are you? |
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| Eric_Shea |
Jul 16 2019, 03:13 PM
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#5
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PMB Performance Group: Admin Posts: 19,274 Joined: 3-September 03 From: Salt Lake City, UT Member No.: 1,110 Region Association: Rocky Mountains  |
I'll play along... (IMG:style_emoticons/default/devil.gif)
It seems the community has gone from: 1. Put carbs on - Early years when old schools couldn't figure out the FI 2. Don't put carbs on - Mid years when shade-trees dug in and became more knowledgeable than most old schools on FI systems. Parts were plentiful. They were/are correct. 3. Here and now... Here & Now, harnesses are brittle, good parts are getting harder to find and, a good FI system requires a knowledgeable tech trained in the art of 50 year old FI systems. My take is, if your system is stock and you have all of the components, it may be worth a shot at saving it. That said, you can easily spend thou$and$ with MPS rebuild, TPS Rebuilds, leaks and bad wiring (a $500.00 harness from Jeff B. would be an EXTREMELY wise investment). I guess my point is, I feel carbs can be a viable alternative as we are beginning to run out of stock FI resources. Good parts are just getting harder and harder to find and, it's an old system. ***They (carbs) will make less power when run on FI cams*** As you move forward plan on a motor rebuild with a substantial cam to take advantage of all that carbs can offer. If you're considering an engine rebuild, I would go 2258 with the new stroker cranks out there and run either carbs or EFI the likes of The Dub Shop's Type 4 MicroSquirt system. An EFI system on a motor like that will change your world. So... *Try to keep it alive if you can. *Don't feel bad if you have to go carbs but, look to the future and make sure you have your eye on the proper cam for the motor eventually so you can take advantage of them. *Did I say look to the future? Modern EFI systems can be almost plug and play these days and they will reward you in technological leaps and bounds. It's amazing.  |
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| lalee914 |
Jul 16 2019, 03:19 PM
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#6
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Senior Member Group: Members Posts: 811 Joined: 13-February 13 From: Georgetown, DE Member No.: 15,521 Region Association: North East States |
You can find the factory workshop manual for the 914/4 fuel injection system and some manuals from Bosch for both the D and K jetronic FI systems here:
http://p914-6info.net/Manuals.htm Hope this helps. |
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| porschetub |
Jul 16 2019, 03:37 PM
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#7
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Advanced Member Group: Members Posts: 4,696 Joined: 25-July 15 From: New Zealand Member No.: 18,995 Region Association: None |
Keep it,I was able to download and print off a complete L-jet FI tech manual which is for a 912E but its essentially the same and very helpful reading.
IMO it important to know how it all works piece by piece and how all the parts should work together,this manual covers it all. |
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| dr914@autoatlanta.com |
Jul 16 2019, 03:40 PM
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#8
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914 Guru Group: Members Posts: 7,810 Joined: 3-January 07 From: atlanta georgia Member No.: 7,418 Region Association: None |
don't do it! Call me personally for tech advice and we can work through it!!
QUOTE(downrange @ Jul 16 2019, 01:16 PM) I am on my last nerve trying to get my 74 1.8 ltr L Jetronic fuel injected car started. Bypassed the seatbelt interlock to get the starter to work. Hot wired the fuel pump to get it working and still no go. I am considering a carburetor conversion and see that Redline has a few kits. The dual carbs system has no choke and the single carb with electric choke has some distance from the cylinder heads. Anyone have any success they could share? |
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| jdamiano |
Jul 16 2019, 04:23 PM
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#9
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Member Group: Members Posts: 335 Joined: 18-March 18 From: Jacksonville Member No.: 21,981 Region Association: South East States |
Love my Redline Weber kit and Petronix distributor. Far less points of failure and it new!! The FI systems on these cars are just old. Can’t fix old. It’s a law of physics called thermodynamics. Keep the FI in a box somewhere safe in case the next caretaker of the car wants it. No shame it wanting new fuel and ignition systems.
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| tejon007 |
Jul 16 2019, 04:31 PM
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#10
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Newbie Group: Members Posts: 45 Joined: 10-February 10 From: Northern California Member No.: 11,344 Region Association: None |
...completely agree with Eric.
It's not what you or I would or should do in such a situation...it's what's right for the owner to decide. So, let's see: Option 1: study-up or find someone that can diagnose an old FI system, including potentially fixing wiring and broken parts that may not be available -- but, can definately be an expensive option? (but, it might also be an easy fix after you know what's wrong) Option 2: bolt on some carbs/manifolds in an afternoon and drive it, even though the cam isn't the correct one Option 3: install modern FI (maybe install a crank sensor) and tinker with it some to set it up correctly. A little more work than installing carburetion and expensive. Other Options: ?? Definately, if you put carburetion on, keep the FI parts in case you decide someday to restore it, which would not be difficult to do once you have all the working parts and the knowledge. New or rebuilt carb can get you back up and running and would be much less than converting to modern FI. Driving your 914 is a good thing! Lots of 914s run dual carbs and IIRC, 914-6s had carbs on them too... |
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| bbrock |
Jul 16 2019, 05:08 PM
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#11
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914 Guru Group: Members Posts: 5,269 Joined: 17-February 17 From: Montana Member No.: 20,845 Region Association: Rocky Mountains
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Convert it to a six, a Subaru, or even a Chevy V8 but for God's sake don't convert to carbs! (IMG:style_emoticons/default/happy11.gif)
I'm with Eric on this. I've been at the point you are now and ended up with carbs. That was decades ago and if it happened today, I would take advantage of all the great info now available to better diagnose my FI to fully understand what would be needed to restore it to a reliable state. Then I would feel like I could make the best choice. Although I'd prefer an OE FI in good working condition, I'd still switch to carbs if it was the quickest and most cost effective path to a running and reliable car. It's your car, your time, your wallet, and your choice. If you decide to go with carbs, I would stay away from the single progressive carb. I've tried those both on a 914 and a bus and got nothing but misery from them. Both those cars ran much better when I switched to dual single throat (34 ICT) carbs that used to be available very cheaply back in the day. |
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| thelogo |
Jul 16 2019, 05:30 PM
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#12
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Senior Member Group: Retired Members Posts: 1,510 Joined: 6-April 10 Member No.: 11,572 Region Association: None |
QUOTE(jdamiano @ Jul 16 2019, 03:23 PM) Love my Redline Weber kit and Petronix distributor. Far less points of failure and it new!! The FI systems on these cars are just old. Can’t fix old. It’s a law of physics called thermodynamics. Keep the FI in a box somewhere safe in case the next caretaker of the car wants it. No shame it wanting new fuel and ignition systems. (IMG:style_emoticons/default/piratenanner.gif) 5 (IMG:style_emoticons/default/beerchug.gif) (IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/pray.gif) |
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| Chi-town |
Jul 16 2019, 05:36 PM
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#13
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Senior Member Group: Members Posts: 850 Joined: 31-August 18 From: Disneyland Member No.: 22,446 Region Association: Southern California |
The stock FI parts are over priced and don't really offer any advantage over a properly tuned set of carbs.
The old "different cam" theory is long dead as the part number is the same for our US market FI cars and the carbed cars in the EU market. Yes you can make more power with a performance cam but that's true on FI also. If you do carbs purchase a new set of HPMX (no cold idle circuit to deal with) from Empi, open the up and inspect and clean them. Dorking around with antique used equipment is not worth it (especially ancient Italian Webers that weren't right from the factory). Get a syncronizer and a wideband O2, set aside a day to drive around and tune then and you'll be very happy. |
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| SirAndy |
Jul 16 2019, 05:55 PM
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#14
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Resident German Group: Admin Posts: 41,602 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
QUOTE(Chi-town @ Jul 16 2019, 04:36 PM) The stock FI parts are over priced and don't really offer any advantage over a properly tuned set of carbs. That's why FI died some 40 years ago and nobody uses it anymore. Carbs rule today's automotive landscape for a reason! (IMG:style_emoticons/default/rolleyes.gif) |
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| Chi-town |
Jul 16 2019, 05:58 PM
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#15
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Senior Member Group: Members Posts: 850 Joined: 31-August 18 From: Disneyland Member No.: 22,446 Region Association: Southern California |
QUOTE(SirAndy @ Jul 16 2019, 04:55 PM) QUOTE(Chi-town @ Jul 16 2019, 04:36 PM) The stock FI parts are over priced and don't really offer any advantage over a properly tuned set of carbs. That's why FI died some 40 years ago and nobody uses it anymore. Carbs rule today's automotive landscape for a reason! (IMG:style_emoticons/default/rolleyes.gif) The stock 914 stuff is to keep it running and reliable. I'd be all for converting it to a current FI setup but nobody wants to spend that kind of cash when carbs are $500 |
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| jdamiano |
Jul 16 2019, 06:21 PM
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#16
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Member Group: Members Posts: 335 Joined: 18-March 18 From: Jacksonville Member No.: 21,981 Region Association: South East States |
QUOTE That's why FI died some 40 years ago and nobody uses it anymore. Carbs rule today's automotive landscape for a reason! (IMG:style_emoticons/default/rolleyes.gif) You misunderstand the point. I don’t see anyone trying to make an argument that carbs are better than FI. Bosch were ahead of their time with the systems they made for the 914 and FI is superior to carbs. The point is 50 year old FI will never be as reliable as a brand new set of quality carbs and a new pointless distributor. |
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| Ansbacher |
Jul 16 2019, 06:22 PM
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#17
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Senior Member Group: Members Posts: 689 Joined: 4-July 14 From: Tampa Bay, Florida Member No.: 17,589 |
Get a good pair of Dellortos. Service them as needed. Make sure your intake manifolds are sealed top and bottom. You will have a great running car without FI headaches. If you use a 009 dizzy, you will not have to worry about any vacuum issues. Bob's your uncle.
Ansbacher |
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| mepstein |
Jul 16 2019, 06:31 PM
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#18
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914-6 GT in waiting Group: Members Posts: 19,221 Joined: 19-September 09 From: Landenberg, PA/Wilmington, DE Member No.: 10,825 Region Association: MidAtlantic Region
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I learned long ago that just because I can’t fix something doesn’t mean someone else can’t do it. Just because the car won’t start doesn’t mean it’s time to trash the system. It could be something simple. You just may need a different set of eyes looking at the problem.
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| SteveL |
Jul 16 2019, 06:45 PM
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#19
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Senior Member Group: Members Posts: 657 Joined: 7-August 03 From: Andover, MN Member No.: 991 Region Association: None
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Please PM me your direct email, and I will send you the Official Captain Krusty L-Jet troubleshooting guide. He sent it to me years ago.
Thank you Cap'n. |
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| struckn |
Jul 16 2019, 06:59 PM
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#20
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Senior Member Group: Members Posts: 1,069 Joined: 9-November 11 From: South Central York Pennsyvania Member No.: 13,764 Region Association: MidAtlantic Region |
Bought my '74 1.8 9 years ago which has the single Weber progressive carb, had the cam changed for carb and it's run like this with no problems no tune ups of mechanical problems. The electric choke works great even in cold weather.
Here's a video coming home from Hershey Swap Meet climbing out of the river vally on the hill. https://youtu.be/wMTxSHz_UKM |
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