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> Weber Progressive 1.7 lag question
Stuie
post Aug 20 2006, 03:55 PM
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I have a '70 1.7L with a single Weber 2bbl.

My Pop has a screamin car which smokes the tires in 2nd or 3rd immidiately when the pedal is depressed and was a 1.8L once but is bigger now with dual Dell's.

I know this engine is not gonna do that but, I feel the time lag between gas pedal to response is too long on this engine. My guess is the intake manifold tube length is resposible for the lag. Does that sound right? Is it the way it is supposed to be or could there be something out of tune?

Right now I am just looking for a crisp response, the power mods will be later when I can afford it. Is the dual carb setup quicker reaction? If that's the issue, which size duals would work with the 1.7L I have now and whatever the engine can be upgraded to later and still work well?

Appreciate the advice!

Stu
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So.Cal.914
post Aug 20 2006, 04:03 PM
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Duel webers are expensive so I think the Q would be how big do you plan to

build your engine. 40's or 44's are to big IMO for a 1.7, you might want to just

do a tune-up and run what you have until you can build the engine you want

and get your carbs then.
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Joe Bob
post Aug 20 2006, 04:30 PM
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The single Pinto/Weber progressive is at best a boat anchor....better yet, get five of them, do the world a favor...... sink them all.....
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Eric_Shea
post Aug 20 2006, 04:31 PM
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Cam (IMG:style_emoticons/default/wink.gif)
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SirAndy
post Aug 20 2006, 04:35 PM
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QUOTE(Stuie @ Aug 20 2006, 02:55 PM) *

I have a '70 1.7L with a single Weber 2bbl.


the single carbs were about the worst aftermarket "upgrade" that was ever sold for the 914 ...

those motors were never intended to be run by a single carb and tuning them even close to "right" is a nightmare.
that is, even in "prefect" condition of all parts involved ...

whoever slapped that "upgrade" onto your car needs to be (IMG:style_emoticons/default/dead horse.gif)


now, that we got that out of the way, i suggest you drive it the way it is until you have the means to upgrade to a set of dual webers or go back to the original d-jet or tinker with an aftermarket FI-system ...
(IMG:style_emoticons/default/smile.gif) Andy
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Al Meredith
post Aug 20 2006, 06:28 PM
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A lot of 32/36 Webers were jetted for VW's. Some packed a bigger Idle jet in the box for use with a 914. Try using a .055 idle jet, you will get much better "off idle " responce.
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Joe Bob
post Aug 20 2006, 06:34 PM
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Whoever first suggested this "upgrade" should be taken out and shot....

Betya it was Dr. 914....what a putz.....
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Mueller
post Aug 20 2006, 06:39 PM
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QUOTE(Stuie @ Aug 20 2006, 02:55 PM) *

My guess is the intake manifold tube length is resposible for the lag. Does that sound right?

bingo, we have winner !!! ....yes, you are 100% correct, the distance the air/fuel mixture has to travel is pretty long, that and combined with the curves it has to deal with, it gets even worse

Is it the way it is supposed to be or could there be something out of tune?

not much you can do about it

Is the dual carb setup quicker reaction? If that's the issue, which size duals would work with the 1.7L I

duals will always be quicker since the air/fuel has less distance to travel and is less likely to have the fuel come out of suspension and stick to the walls...40s seem to be a popular size.
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Joe Ricard
post Aug 20 2006, 06:39 PM
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I can't add anything more to what's already been said.

If you had to run up the street breathing through a straw you would have a lagg too.
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bd1308
post Aug 20 2006, 06:41 PM
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weber 40s might be a tad too big for a 1.7...

I dunno
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Stuie
post Aug 20 2006, 08:06 PM
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All of you guys kick arse!

I sincerely appreciate the time you guys are taking to reply to my questions. I can't thank you enough. I sold a 2000 Jeep on Monday to get my house foundation fixed (Dry spell in Dallas tearing 'em up this year) and planned to get a VW bug/bus beater for about $1500 and ran across this 914.

I learned to drive in a 914 so I couldn't have been any luckier to find it! Being, I sold my dependable cage and got the Porsche for my daily, I thank you guys for the advice so I can handle the issues as quickly as possible. Hope to be able to return the favor sometime...

All best
Stu
www.antstuie.com
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