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> Changing to carb(s), which set up best for everyday driving?
EJP914
post Sep 20 2010, 05:51 PM
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I am changing my 73 1.7 to carbs. Too many FI problems, adjustments, etc. I have read here and elsewhere that no one seems to like the single carb set up. Why not? What are the issues? I have a 74 1.8 that the PO changed to a sgl carb and it runs pretty well. Besides, sgl carb set up is cheaper.

If I went to 2 carbs, is there any big drivability difference between Weber 34 ICT and say 40 IDF. There is a big price diff.

Not looking for any big performance increases. Just something reliable.

Anyone ever dealt with a company in NY called Weber Carbs Direct? Prices looks good.

Thanks for the input and guidance.
Ed
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rick 918-S
post Sep 20 2010, 05:55 PM
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Unless you are changing the F.I. profile cam along with the F.I. you'll be fighting an up hill battle. The stock cam does not like carb(s).
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VaccaRabite
post Sep 20 2010, 06:29 PM
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If you just want to be able to get in the car and go, and do not care much about performance, the single carb will get you there. It is cheap and easy. The trade off is that you will be leaving a lot of power on the table. Maybe 1/3 of your 80ish HP will be stolen due to the setup. It will be sluggish in the cold when the gas falls out of suspension in the intake runners.

But, it will get you there, your car will be up and running.

Duals are just as hard to tune as the FI is, but its a different process, and you get nearly as much power as with FI. Change the cam in the engine, and you can get more power with dual carbs as with FI.

But if want the best driving car, you do want to get the FI working.

Zach
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JoeSharp
post Sep 21 2010, 07:23 AM
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Hey Ed. I have done a bunch of carb conversions. If your looking to get a great DD out of your car put the twins on it and you will be happy. They will be down on power a little but will get you over 40 MPG at freeway speeds. Linda's 1.7 got over 49 MPG at one point and she never complained about the loss of power.
Should you decide to go this route you will need some parts beside the carbs. I have found that the CB Rotery fuel pump to be much better than the Faucet and it comes with the filter. Also you will need a good linkage.
Good luck with your desision.
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flipb
post Sep 21 2010, 08:04 AM
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QUOTE(EJP914 @ Sep 20 2010, 07:51 PM) *

I am changing my 73 1.7 to carbs. Too many FI problems, adjustments, etc. I have read here and elsewhere that no one seems to like the single carb set up. Why not? What are the issues? I have a 74 1.8 that the PO changed to a sgl carb and it runs pretty well. Besides, sgl carb set up is cheaper.

If I went to 2 carbs, is there any big drivability difference between Weber 34 ICT and say 40 IDF. There is a big price diff.

Not looking for any big performance increases. Just something reliable.

Anyone ever dealt with a company in NY called Weber Carbs Direct? Prices looks good.

Thanks for the input and guidance.
Ed


I have the single-carb setup on my '74 2.0. It runs fine as long as the weather is warm. However, when outside temps are below 55-60 degrees, it can be downright dangerous... it takes a very, very long time to warm up and for most of that time, you can never be sure if giving it some gas will cause the desired result (vrooom) or flood the engine. The culprit, as others have said, is the long intake runners which give the fuel time to precipitate out of the air mixture and form droplets.

I'm very happy with it for about 7 months of the year, but I see you live in a climate like mine... My winter project this year is to seek out a good set of 40mm dual carbs and switch it over, hopefully with Jake Raby's new cable linkage.
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carr914
post Sep 21 2010, 10:48 AM
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ChrisFoley
post Sep 21 2010, 10:49 AM
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QUOTE(Vacca Rabite @ Sep 20 2010, 08:29 PM) *

... Maybe 1/3 of your 80ish HP will be stolen due to the setup...
Zach

(IMG:style_emoticons/default/bs.gif) Where do you come up with this stuff Zach?
I'd be shocked if even 10hp was lost due to running a single carb setup on a 1.7L.
On the other hand, I suppose a single carb could be set up so badly by some people that only 50hp was available. (IMG:style_emoticons/default/bootyshake.gif)
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angerosa
post Sep 21 2010, 11:24 AM
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I have a single carb on a 1.8. I've had it for 5 years now. I've never rebuilt it or done much carb tuning. I drive my car as much as weather and life allows. It does perform differently in different weather conditions but I've gotten used to it. I don't believe I have a non oem cam in there. So while I would think that fuel injection would be less maintenance, I can't say I have any experience (at least with my 914) supporting that belief.
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tradisrad
post Sep 21 2010, 11:29 AM
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Be patient and work out your FI issues. Once you get it dialed in you will be happy. There are lots of resources to figure out the FI. My 2 cents. http://members.rennlist.com/pbanders/djetparts.htms
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VaccaRabite
post Sep 21 2010, 12:07 PM
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QUOTE(Racer Chris @ Sep 21 2010, 11:49 AM) *

QUOTE(Vacca Rabite @ Sep 20 2010, 08:29 PM) *

... Maybe 1/3 of your 80ish HP will be stolen due to the setup...
Zach

(IMG:style_emoticons/default/bs.gif) Where do you come up with this stuff Zach?
I'd be shocked if even 10hp was lost due to running a single carb setup on a 1.7L.
On the other hand, I suppose a single carb could be set up so badly by some people that only 50hp was available. (IMG:style_emoticons/default/bootyshake.gif)

It was I was told when I was asking these questions. And at the time a lot of people agreed. The whole "boat anchor" contingent back in the club days. If its worng, so be it. But it was enough for me to put single carbs out for good. But for what its worth, I would not at all be suprised that a 36 year old motor that someone put a single carb on to "fix" FI issues would only have ~50hp. Sure, new rings and heads that don't leak and you may get a lot of that back. But if you spent the money to rebuild the top end, would you really put the single carb back on? (IMG:style_emoticons/default/bootyshake.gif)

Zach
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Cevan
post Sep 21 2010, 01:30 PM
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I also would suggest getting the stock FI to work properly. There isn't much to adjust on D-Jet (TPS; fuel pressure; idle mixture screw).
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Drums66
post Sep 21 2010, 04:10 PM
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QUOTE(tradisrad @ Sep 21 2010, 10:29 AM) *

Be patient and work out your FI issues. Once you get it dialed in you will be happy. There are lots of resources to figure out the FI. My 2 cents. http://members.rennlist.com/pbanders/djetparts.htms


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