Weber dual carb conversion documentation
 

I have recently acquired a '74 914 that has been converted to dual Weber carbs.
The compression and everything with the engine has been checked out and are fine, but the carbs need to be tuned badly. Right now, it sputters and backfires under 3k quite a bit and idles high.
I want to get the carbs (as well as the engine in general) tuned up, but want to have the documentation on the carbs before it is tuned. Where would I find documentation on these?

Thanks.

Documentation??
 

I Think what you are asking is what size carb, WEBER/Delorto, Jet sizes, venturi size???
Only you can find this info by inspecting what you got.
Jump in and tell us what you got and you will have more help that you ever thought.
Something like WEBER, 44 IDF 36MM venturi, 60 idle, 135 main gas, f11 emulsion, 200 air correct.
Engine size/displacement, Cam profile would help, exhaust design too. SmileWavy

Joe,

I think I am about to convert from the L-Jet to carbs. It was originally a 1.8 but now has 2.1 displacement. Are the dual Webers the best choice? If so, where should I look to purchase them? I understand that I'd need a 009 dizzy and Facet fuel pump. Any other suggestions?

GS

Hop on to Webers web site. There are very simple instructions there. Also - you may try doing a search on this within this BBS. I know a posted a step by step, but can't remember if it was here or on the Rennlist.
Scott S

Jabez, DO NOT convert to the 009 distributor. The advance curve is wrong for the Type 4 engine. There are numerous posts to this and the Rennlist boards on the 009. If you must go all mechanical advance, use the 050. If you don't HAVE to go all mechanical, use the stock distrbutor and hook up the vacuum port for additional advance. The PO used a 009 on my car when he converted it (2056, cam, dual 40 IDF's) and I ran it that way for several years. After reading numerous posts and discussions, I tried the stock didstributor (included by the PO) and it was a very real improvement. Started easier, pulled more smothly in hte low and mid ranges. Most Webers made in hte last 15 years or so (maybe longer) apparently have vauum ports installed. They arecapped with a small screw-in plug. Remove the plug, connect a hose to the advance canister, and you have vacuum advance.
Yes, you will need a Facet, or some other low pressure fuel pump. Carbs are usually rated in the 2-4 PSI fuel inlet pressure rather than the 28 or so for the FI system pump.
For a 2056 with a moderate cam, 40 IDF's, Crane HI-6, PS91 coil, Pertronix Ignitor, and plugs gapped at 0.045" I'm running:
28 mm venturies, 0.45 idle jets, 1.20 mains, F-11 emulsion tubes, and 2.00 air correction jets.

Good luck,
Harvey

Weber IDF's work well, but some people prefer Dellortos which are no longer being made but can be found used. Many places sell Webers, Aircooled.net and CB Performance included. They can help you with size and jetting. Few people recommend the Bosch 009, the 050 is preferred. The stock distributor will work too. The Mallory Unilite ($$$) is probably the best for the application. The facet pump will do the trick but is a noisy little devil. Mount it on rubber isolators. Be sure to get the model that delivers 3.5 psi as Webers need only 3-4 psi.

Do a search in this forum and in http://shoptalkforums.com/ (Type4rum) for Webers, carbs, fuel pump, distributor, etc and you'll find a bunch of good info.

Mike

Thanks guys!!! I love this BBS!!! How do you think my standard WEBCAM will work with the carbs?

GS

Any cam will work with carbs. You won't be getting the most out of the carbs if you use the stock mild cam, though.

--DD

This has been helpful, but let me rephrase my question a bit.
The car is actually a friends I am holding onto until he can pick it up and return it to Oklahoma City.
No manuals came with the car, and I have recommended to him (I've been the eyes and ears down here finding it) to get either an original manual or a Hayes manual before he, his brother or any mechanics work on the car (for reference). It is a bone stock '74 2.0 with the exception of the different carbs. I know the carbs are out of tune, and was wondering what kind of reference document exists for these. I imagine since they are not factory they are not covered in the Hayes manual.

Thanks again.

You're correct, they're non-stock (no 2.0s were carbed except for the 914-6es) and the manuals would not cover them. Check the "CDs and documentation" section of Pelican's catalog for a Weber carb book. I've heard it's pretty decent. There's one other book that is supposed to be even better, but it's out of print. (By Pat Braden, maybe?)

CB Performance also supposedly has some good Weber books.

--DD

Dave,

Am I going to gain anything (hp and performance) by adding the carbs and still using the standard Webcam?

GS

Maclif,

Haynes prints a good manual for Weber Carbs. It covers many different carb types including the typical IDFs. I use this for tuning instructions and rebuilding. Another manual that I have used for carb tuning is the Clymer 914 manual which covers both 4 and 6 cylinder models and has tuning instructions for the carbed six. The tuning procedures for two barrel and three barrel carbs are essentially the same.

You may want to try the Haynes Weber manual if this is the type info you need.

Mike

Thank you for the help.

I'm going to go find some books now.

jabez, this is a bit of a controversial subject. My take on it is: Nope. Or rather, you may gain a small bit of power at high RPMs, but this will be offset by a loss of power/torque at lower RPMs. Not to mention the poorer driveability, worse cold-start behavior, etc.

If you go with an aggressive non-stock grind, that's where the carbs really make a difference. (In large part, because the stock FI just won't run right with the cam.)

--DD