Jetting recommendations for Weber 40 IDF's

Bruce2 · Post by **Bruce2** » Sun Mar 26, 2006 9:37 am

Gabe wrote: .....and feel how the engine runs. If too rich,..... .

You can't "feel" the correct A/F ratio.

I guarantee, a 130 main, and a 55 idle is too rich.

Gabe · Post by **Gabe** » Sun Mar 26, 2006 9:40 am

Found another setup article on the net, that has a lot of good setup/tuneup information:

http://home.earthlink.net/~simeons/weber.htm

Pulled my idle jets: Marked "52" (supposedly drilled to "55" according to the sticker on the carb box. Why couldn't CB have just left them at 52/115? Seems like that would be a perfect setup. I'll give them a call this week to ask about the jets.

Float levels were definitely off. Glad I took them apart.

Bruce2 · Post by **Bruce2** » Mon Mar 27, 2006 12:30 am

CB has always supplied their carbs too rich. It is a good marketing strategy, a rich carb will always run fine (just get crappy mileage). A lean carb will never run well. For a novice who know nothing about carbs and living in the far reaches of the world, rich settings allow for a successful installation. However, today with this interweb, help is nearby and instant.

If you want your car to run just "ok", and you don't mind the odd fouled spark plug, and you are fine with low mileage, and you don't mind frequent trips to the gas station, run the jets the way they are. Otherwise, jet it properly. Then make more hp, get better mileage, have longer engine life, pollute less......

Gabe · Post by **Gabe** » Mon Mar 27, 2006 8:29 am

I definitely plan to get the correct jets before I install them (probably 115/52, like they come stock). I'm going to contact CB and see if I can return these jets for some stock jets, as I never requested they be drilled.

On another note, are velocity stacks worth it for 40IDF's? I notice that the larger 44 and 48's come with them, but the 40's didn't. I need to order a "snail"/unisyn to sync them, and thought I'd also order the velocity stacks if they are worth it for air flow. I'd think they'd also create a better seal when syncing with the unisyn.

Bruce2 · Post by **Bruce2** » Mon Mar 27, 2006 9:37 am

It is a very good idea to get the velocity stacks. You will make more hp with no penalty.

Don't bother asking CB for a refund, in their opinion the big fat jets are correct. Start with a 115 main and a 50 idle jet. I have run a 47 idle jet with no ill effects.

I once swapped e-mails with Bob Tomlinson (owner of CB) about this very topic. He was trying to tell me that according to his vast experience that my jets (in my Dellortos) were way too lean. I tried to explain that according to the 5 gas exhaust analyzer while my car was on a chassis dyno that he was wrong. My O2 sensor also confirmed my jetting.

Gabe, if you are serious about having the correct A/F ratio, you should look into one of the available O2 sensors, like an LM-1. Do a search.

Gabe · Post by **Gabe** » Mon Mar 27, 2006 10:13 am

Well, I just got off the phone with one of the sales reps at CB. As Bruce said, she gave me the song and dance that stock 115/50 would be too lean, and that everyone loves buying their carbs because they "do all the setup work for you, including drilling the jets" (I didn't mention to her that my floats were way off, as I didn't want to get into an argument). Asking her for a simple swap of jets, my drilled ones for a set of stock, she said "no swapping/exchanges." I even mentioned that I was willing to buy some items (the previously mentioned stacks and unisyn) so they wouldn't have to pay extra shipping. "No swaps." I'd have to buy new jets.

I explained to her that nowhere on their website do they mention drilling out the jets for their carbs (I ordered them off the net), after which she stated she'll look to see if they have some smaller jets in the back. Supposedly she will call me back tomorrow morning, as "she is very busy."

After all of the rave reviews of CB's parts/carbs (the reason I chose to buy from them), I just hate running into a situation where a business does not go out of their way to make sure a customer is satisified (it's not like I'm asking them to go that far out of their way). Maybe I should have gotten them from ACNet instead, as I've heard John's customer service is top notch.

RoWaMe · Post by **RoWaMe** » Mon Mar 27, 2006 11:54 am

gabe, even though you don't have something small enough to accurately measure the exact size to which your mains have been drilled, you can certainly get a good "relative" measurement, I guess, if you have a stock Solex single carb main jet which you use as reference. Get a wooden toothpick, insert it into the Solex's main jet, and mark off (or even cut with a shrap utility knife) the end that comes out the other end. Note the size of the Solex jet; they are usually smaller than 130. Then stick the cut toothpick tip into the Weber main jet. If the tip comes out clearly past the jet tip, the Weber jet is a larger size than the Solex's. If the tip does not protrude, it is either the same size or smaller. Make sense? Just be careful and use a very light touch...

Still, I hope you get a constructive resolution.

Bruce- those 40 IDFs on your 2-liter- that engine had 40mm intake valves, not the stock 35s, right? I'm surprised it revved that high with the 28mm vent's! Must've pulled like a bear down low...

robbied31 · Post by **robbied31** » Mon Mar 27, 2006 12:23 pm

Gabe,
I have always been happy with CB parts, always! But their customer service and backlog is crap! That's why I won't buy from them anymore. That is unles I am in a pinch. If you were talking to Marie Ann there, she wasn't lying, they have her running that whole place and she needs help. It takes me over a week to get parts from them and they are no more then a 3 hour drive away. I get parts from CIP1 in a matter of 2 days, and they are a hell of a lot further away!!!!!!!

Good Luck

Rob

Gabe · Post by **Gabe** » Mon Mar 27, 2006 12:43 pm

Not sure what her name was, but my initial order e-mail from them did mention a backlog (I ended up getting the carb kit in about a week and half, which wasn't bad). I too like to order parts from CIP1, as they seem to have very reasonable prices. They are currently in the process of shipping my new muffler system, and I'll probably pick up the velocity stacks and flow meter from them unless CB changes their story.

(Tax return came through nice this year, so I decided to splurge on my Ghia with new carbs and muffler; even though the wife thinks it's a money pit. So what if it is, it makes me happy after slaving away at work during the week.

)

JohnConnolly · Post by **JohnConnolly** » Mon Mar 27, 2006 12:50 pm

nobody can TOUCH our carb setup, which is why we cost more then the other guys (and our carbs INCLUDE velocity stacks and air filters; why wouldn't they?). Most folks don't realize how much there is to getting them setup, they are NOT even close to ready as you get them from weber. And we know what we are doing with them, we don't expect the consumer to be as knowledgeable about them, and it's easy to mess up, so we just do it to every set before they ship. Even many "experts" jet the carbs at WOT with the wrong setup, and they run like pigs at part throttle (and people wonder why). Who drives at WOT all the time and doesn't care about part throttle or off-idle drivability? Or who likes getting 12mpg when they should be at 28-34mpg? Sheesh.

It's all a matter of what your time is worth. And buying jets you already paid for is a real biatch and pisses some people off (we have a jet exchange program to minimize this BTW). But me trying to convince people of the fact beforehand is a waste of time, but people always say they wish they knew beforehand (it's not like we are hiding it), after they are tearing their hair out trying to work with carbs that are all jacked up and have drilled jets (to unknown sizes). In the end they pay the same as they would have if they bought them from us, but I don't even bother trying to explain this anymore.

Drilled jets is the 2nd biggest mistake prevalent on Weber tuning, which is why you should never EVER do it. Why you'd do that to BRAND NEW jets is crazy.

There was an interesting thread on this at http://www.speedsterowners.com/forum/readmsg.asp?t=8390

John
Aircooled.Net Inc.

Gabe · Post by **Gabe** » Tue Mar 28, 2006 5:21 pm

Get ready, long story:

Never received a call from MarieAnne. I ended up calling CB myself again around 2:30pm (Pacific time, dinner time for me on the East coast), and spoke with another lady who said that MarieAnne was on her lunch break, and that she would call me back within half an hour when she returned. 3:30pm rolls around, no call. I call back and speak with the same girl, who says that MarieAnne is on the phone, and that she will call me back immediately once she gets off. 4:30, no call from MarieAnne.

I call CB again, this time a guy answers. I explain my situation again ("never requested drilled jets; engine carbs will be going on; no mention of drilling/alterations on their website, etc . . . "). Get transferred to Aaron, who does their carb setups. Nice guy, who understood my situation and agreed that they drill them like this because most people don't know what they're doing setting up dual carbs, and the richer setting would help prevent people from bitching to CB. He said that they had some stock jets and that once they receive my drilled jets, they can send me the stock ones. Sounds great. He just needs to OK it with the customer service folks. . .

Aaron gets back to me and says sorry, "no jet swapping" policy. I then ask to be transferred to his boss. Rick answers the phone, I explain my situation again, he reiterates the "no jet swapping" policy. I repeat that these jets are unused, just as I received them, and will definitely run too rich. He states that they've been shipping them like this since 197x, that Weber carbs are next to impossible to get these days, and that I'd have to buy new jets. I quote their sales slip to him: "We value you as a customer and will make every effort to keep you happy" and ask him if they are going to change their website to mention that they alter/drill the jets from stock Webers before shipping. He finally says that he will ship me four 115 main jets (no mention of stock idles). At this time, I'm fed up with the whole situation, so I agree and say that I will ship my drilled jets to him when I receive the stock ones. He then says he doesn't want them, as I "have already cost them the price of another kit with my calls to four of his people."

Long story short: I will no longer be giving CBPerformance my business. They may make great parts, but their customer service is terrible.

fortyeye · Post by **fortyeye** » Tue Mar 28, 2006 8:02 pm

I'm with John C. and Mark on this one. I cannot fathom why C.B. still drills brand new jets. They ship carbs with dirt and grit (so do several other companies) inside the carbs, no float setting (or they change during shipping?), and drilled jets. There is enough information (thank you John) available to preclude all but the complete novice (who shouldn't be installing dual Webers in the first place) from running too lean. Things like float levels, clean internals, known jet sizes, and correct fuel pressure are all covered with a purchase from aircooled.net. C.B. isn't the only company that drills jets. If anyone chooses the EMPI HPMX carbs ... better have a jet guage handy. I have seen these "brand new" with drilled jets. Webers (I've always been partial to 40's) have a long connection with our choice of performane mods. I applaud C.B. (since the days of Claude's Buggies) for many of their improvements in the basic design (their Jet Doctor kit goes a long way to reduce idle jet clogging in off-road applications). The collective brain power here - John, Mark, Bruce, etc. provide the technical "grout" that fills the seams and keeps us all "stacking our bricks straight" when it comes to setting these carbs up. Don't forget to verify your fuel pressure ... good luck.

Bruce2 · Post by **Bruce2** » Tue Mar 28, 2006 9:01 pm

Gabe wrote:
Aaron, ...... agreed that they drill them like this because most people don't know what they're doing setting up dual carbs, and the richer setting would help prevent people from bitching to CB. .

I am very surprised that you got someone at CB to admit what I have known for years. Richer than correct A/F ratio will always run fine.

seahag · Post by **seahag** » Wed Mar 29, 2006 10:54 am

I'm not trying to stir the pot here, but out of personal experience in dealing with John Connelly, his professionalism and knowledge in buth business and the air cooled engine makes him a person that is worthy of ones confidence in dealing with him. Many purchases and $ later, he is still a man of integrity and knowledge. Seahag

Gabe · Post by **Gabe** » Wed Mar 29, 2006 11:50 am

Live and Learn. I need to order some pushrod tubes in the near future. John Connelly will be getting my business.