Why not carbs?

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radavidson
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Why not carbs?

Post by radavidson » Mon May 13, 2002 2:02 pm

I've been a long time VW person and have installed a multitude of dual carb configurations on Type I motors. Every where I turn I hear don't put carbs on a 914 Type IV. I can see some increased gas consumption but I guarantee I can make a set of dual Weber's run as good as a fuel injections system. It will also be as reliable if not more reliable. One of my dual Weber Type I motors is pushing 50K miles without a single carb adjustment. Most of the tech questions I see are concerning problems with the injection systems. If they run they are great, but they seem to be a problem most of the time. They are also expensive. Give some fact based reasons why I should not convert to dual carbs. I can be persuaded to go FI, but I need some facts.

Ryan72
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Why not carbs?

Post by Ryan72 » Mon May 13, 2002 4:32 pm

Amen brother. The bosch d-Jet was the reason my present 914 sat in front of my uncles house for 10 years. Sure its great when it works, but not all of us have the time/paitence or skills to troubleshoot a system that is plagued by problems(especially when many parts are 30 years old). The parts are expensive to replace, few people have knowledge of the FI, and problems can be intermitent. I know this will get about 10+ responses of "well my bosch FI works great and has for 5+ years" or whatnot, and there will always be exceptions to the rule(for example I actually know a few people who have FORD cars or trucks that actually DONT have many problems!!) BUT if you take the situation as a whole, and figure out the percentage of 914s that sit as apposed to being driven, and figure out why they are not road worthy, 90 percent of them are due to FI problems.
Sorry to be so long winded, GO FOR THE CARB SWAP, its the best thing that I ever did to my 914.

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Bleyseng
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Why not carbs?

Post by Bleyseng » Mon May 13, 2002 4:43 pm

Fuel Injection is just a more accurate method of mixing/metering the gas into the combustion chamber. FI has better atomization of the fuel than carbs with less chance of condensation of the fuel.
On a stock 914 motor you make more torque at low to mid rpm's than with carbs.
Better driveabilty than carbs as FI adjusts for weather and altitude conditions.
In hard cornering with FI you never have fuel starvation as with some carbs.
Djet is adjustable like carbs and can be tuned for your own motor like carbs.
FI is a set it and forget it system unlike most carb set ups.
That's just a couple of reasons off the top of my head...
Geoff


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76 914 2.0L

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Bleyseng
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Why not carbs?

Post by Bleyseng » Mon May 13, 2002 4:51 pm

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Bleyseng:
<B>Fuel Injection is just a more accurate method of mixing/metering the gas into the combustion chamber. FI has better atomization of the fuel than carbs with less chance of condensation of the fuel.
On a stock 914 motor you make more torque at low to mid rpm's than with carbs.
Better driveabilty than carbs as FI adjusts for weather and altitude conditions.
In hard cornering with FI you never have fuel starvation as with some carbs.
Djet is adjustable like carbs and can be tuned for your own motor like carbs.
FI is a set it and forget it system unlike most carb set ups.
That's just a couple of reasons off the top of my head...
Geoff


</B><HR></BLOCKQUOTE>

The cars that don't run with FI usually have never been maintained properly. The same would apply to cars with carbs 30 years old. There is no free lunch, maintance costs money and these cars do cost money to maintain. Ripping out the FI is the ignorant way of fixing the problem. Most of the time it can be fixed with some cheap part like a temp sensor. There are web sites now that any mechanic can use to troubleshoot the FI and repair it himself at home.

Ryan72
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Why not carbs?

Post by Ryan72 » Mon May 13, 2002 5:46 pm

Most D-Jet parts are not cheap, sometimes tough to find, and there are too many links in the chain. If it is not one peice failing its another, I would NOT say ripping off fuel injection and replacing it with carbs is an ignorant way to fix a problem. My uncle is a mercedes mechanic and frame specialist for a living, He knows his stuff pretty well(thoough deffinatly better now then he did 10 years ago) Point being, you can spend your time troubleshooting problem situations with your injection, or you can put carbs on it and enjoy driving the car without worry or mystery as to why it wont idle, why it wont start etc. Whatever you do, if its a 914 its going to be a blast, that is one thing we can all agree on, and anyways, that bosch D-Jet sure as hell wouldnt have been able to feed my new 2270 baby. :oD

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Bleyseng
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Why not carbs?

Post by Bleyseng » Mon May 13, 2002 7:01 pm

No, Djet wouldn't run 2270 with a big cam, it should be able to run it with a stockish cam though.
A better Bosch FI would be Kjet which Raby is trying out.
There are several other aftermarket FI systems that are being used on type 4 too.
Carbs do work but why rip out something that works great? Djet FI does work well in these cars. Parts? well most car parts for cars that are 30 years old are going to be expensive but parts can be had. (Try to find a set of nice sunvisors!).
My car came without the Djet on it and I was able to re-install it without any real problems. I am just a hobby mechanic too.
Geoff

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76 914 2.0L

radavidson
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Why not carbs?

Post by radavidson » Tue May 14, 2002 2:19 am

I do not have the FI for this car, it's a 2.0 with Weber 44 IDF's. I have not heard anything that would make me spend the money to buy FI when I already have carbs. I am re-building the motor, so I don't care if it's been abused. My 72 Ghia with a 2085 cc motor and Weber 44 IDA's has been on the the road for 1 year and about 4K miles, no adjustments required so far. FI is great when it works but a pain when it doesn't. I can't justify the big dollars to purcahse an entire FI sytem for a 2.0. If someone wants to donate it to my cause I would be glad to give it a go.

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Randy Davidson
72 Karmann Ghia Coupe <A HREF="http://www.smallwonderdesigns.com/72ghia.htm
74" TARGET=_blank>http://www.smallwonderdesigns.com/72ghia.htm
74</A> Porsche 914 2.0 http://www.smallwonderdesigns.com/914.htm

Ryan72
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Why not carbs?

Post by Ryan72 » Tue May 14, 2002 10:07 am

The fact that you already have carbs and dont have the EFI is even more reason to use carbs. Dont sweat it, use what you have, it will work fine, granted... If I knew then(when I took my injection off) what I knew now, I would not have tossed my injection in the trash can, and not that vacuum advance dizzy either!

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Bleyseng
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Why not carbs?

Post by Bleyseng » Tue May 14, 2002 11:30 am

Randy, I went to your site and checked out the pictures. Boy, lots of work to do but the car does follow about what I said 'The cars that don't run with FI usually have never been maintained properly."
If you are going to restore it then keep and eye out for a FI set up to put back on. The car will be worth more (resale) and your wife will love you all the more for it. The FI is much quieter and you can actually talk inside the cabin as you drive! Yeah, yeah, guys like to hear the carbs sucking but it is loud and on a trip gets real old.
Geoff
Geoff

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76 914 2.0L

radavidson
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Why not carbs?

Post by radavidson » Tue May 14, 2002 2:52 pm

You should see the car now. You would not recognize it. I plan on having it done in a couple of months. Yes, I work fast, but I do a good job. I did the Ghia in 8 mos, 4 mos of that was waiting for the paint guy to do his thing. I'm painting this one myself. 3-4 months total. I work on it almost every night. Plus play tennis three times a week, plus build web sites for extra car money. If you can't tell, I'm hyper!!!!


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Randy Davidson
72 Karmann Ghia Coupe <A HREF="http://www.smallwonderdesigns.com/72ghia.htm
74" TARGET=_blank>http://www.smallwonderdesigns.com/72ghia.htm
74</A> Porsche 914 2.0 http://www.smallwonderdesigns.com/914.htm

Brett Anderson
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Why not carbs?

Post by Brett Anderson » Wed May 15, 2002 8:18 am

After much deliberation, I am converting to the dark side by pulling a perfectly good working D-Jet system. I search for more power, I am building a 2270 and, from what I understand, the stock D-Jet would be inadequate.

I was planning to keep all of the parts to convert back to later, but I realize that that is very unlikely and I should just sell them.

Before I go and advertise it, how much do you all think a perfectly working 2.0 d-jet system(from the fuel pump, to the air box to injectors, everything) worth? If I can't get enough for it, then I'll keep it.

radavidson
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Why not carbs?

Post by radavidson » Wed May 15, 2002 10:41 am

Brett,
I sent you an email. I would be interseted in the system if you come up with a price. Does it include the correct dizzy?

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Randy Davidson
72 Karmann Ghia Coupe <A HREF="http://www.smallwonderdesigns.com/72ghia.htm
74" TARGET=_blank>http://www.smallwonderdesigns.com/72ghia.htm
74</A> Porsche 914 2.0 http://www.smallwonderdesigns.com/914.htm

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Bleyseng
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Why not carbs?

Post by Bleyseng » Wed May 15, 2002 11:58 am

The stock Djet won't work only if you use a different cam. The Web cam #73 does work but the idle is alittle funky. Djet and the stock intake set up works until about 2.4l, beyond that and it doen't flow enough air.I know Raby says for his 2270 it won't work but that is with his cams.
Price of a 2.0l Djet complete depends on condition of course but somewhere around $300-500.
Geoff

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76 914 2.0L

ray greenwood
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Why not carbs?

Post by ray greenwood » Thu May 16, 2002 3:12 pm

I have yet to see a stock carbed type 4 engine that would produce a better power curve and better fuel milage to boot...than a fuel injected model of the same engine. And yes they would both be a little different configuration. As stated in an earlier post, 90% of all tunability problems in D and L jet were owner related (read maintenance). The cam problems with D-jet are related to valve opening point timing...and not so much to lift and duration. The web #73 works quite well. A little more lift and duration...and almost identical valve timing. The idle problems are related to the exhaust valve overlap gained through longer duration and the need to not respace the intake timing. It can be adjusted out for the most part with a little work to the timing location of the trigger points and proper adjustment of the pressure sensor. That...by the way...is the heart of why so many people had problems with D-jet. You make changes to an carburated engine and you expect to have to readjust the fuel mixture...and maybe even change a jet size don't you? So why would it be any different for FI? You make any moderate change that rsults in a higher state of tuning or efficiency...and you have some adjustments to pressure sensor and vacume signatures to make, which most people did not, either through not being able to find info, not having basic tools (which are really basic these days)...or just plain being lazy. Go with the injection...it will run better than the carbs...BUT...assemble the engine with the correct parts that the injection required. IE...distributor, advance unit, cam with correct timing, all the fuel loop parts...and the correct if not better...compression. Ray

threehouse
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Why not carbs?

Post by threehouse » Thu May 16, 2002 4:21 pm

I have an FI setup from a 1.8 914. I'm not sure if it is a D-jet or L-jet system?
I will be using carbs on my motor and will not go anywhere near the FI setup - I know very little about it and that's about as much as I want to know (for now).
If anyone has a need for it, I'd rather not see it sit and collect dust/take up shelf space, etc...
i can send photos to anyone interested. I know that it came off of a running car - it includes distributor, brain, air box, injectors, intake runners, hoses, etc..
I don't know what to ask for it, but I'd like to get a fair deal for me and the buyer.
Contact me if interested - squarepeg67@yahoo.com
Thanks!

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