Heroez

Maybe other clues to the mysterious markings on the transmission case are just waiting to be discovered.

Imagine what can be found in the FSM.

Hmm. I suppose I would rather stick with the L28 exhaust manifold. I kinda want to do a 'before' dyno and use that to compare that to after the dellortos.

Ok cool. Now the exhaust. Do you think going up to a 2.5 exhaust for good measure is in balance with the 40s? With 45s or 50s its a no brainer to go bigger. And is it necessary for a propper system to have a header? I have read that the mixture can hover in the mouth of the carb from an exhaust pulse. The long tube header has a scavenging effect that corrects this. Im not a big fan of the noise and heat of a header. Will a stock L28 Exhaust manifold be OK?

This may sound crazy but I am making a choice on how to run the fuel line by the number of hose clamps. Each carb has the single fuel inlet as of now. Using 3 T shaped fittings has the most hose clamps, more potential for leaks. Swapping in the dual fuel inlet part where the carbs are bridged together gives the least amount of hose clamps, beating out a triple fuel rail by 2, T connections by 3. The dual fuel inlets are less than half the price of a triple fuel rail, and twice as much as three T fittings.

Its OK. I have gained a lot from you already and your feedback is valuable. I was just testing the waters on what I have been studying, at least in theory with that question. That is why I threw out the jetting figures. To discuss in theory, if it seems within reason to work with the motor. I just want to be sure I dont mess up, damage the carbs or my engine, or otherwise have a bad outcome. The more things seem correct, I feel like the risk of a bad outcome is reduced.

Maybe a different emulsion tube choice would have corrected the rich idle if the idle and low speed operation are closely related? Or is my theory flawed?

Im also still researching spark control. Mallory unilite seems to have mixed reviews. Megajolt seems cool but I would like to keep it simple and mechanical. Decisions! Ugh.

Now through the holidays I had time to read, study, search and ask questions. I got up the courage to take some parts out to examine the numbers. This is what I found- Main Air Correction is 180, Main Emulsion tube is 7772.5, Main Jet is 132, Idle Jet is 50. Idle Air Corrector/Jet Holder was marked 7850.1 (0 looked like C). This is in the middle of the range from weak-rich according to CB performance. From what I have read the Main Air Correction is good. Main Jet to Venturi size is a bit big. 30 x 4 = 120 so 132 Main jet is a bit rich but way better than too lean. Idle jet may be a litte small at 50. Main Emulsion tube... Umm, still unsure. Anyway, how do these numbers look to you folks?

The510realm, a forum for the 510 crowd, has new members post an introduction before you can post at all. Admins look at your introduction draft and if it passes (very slack) requirements then it is posted in the forum for everyone to see. Then you can post new topics. Im a moderator at another forum. Each day without fail, there is something I do not like, a mistake, spam, etc. I was given the power to use my judgement in what I would tolerate. When it comes down to it, I let a good bit slide when it comes to new members. Sometimes I will just tell them to search, then lock the topic. Kind of like a public disgrace. I did that recently with a wheel fitment thread. Today someone asked where to buy a cheap timing light. Delete! Its tempting to hit the ban button, but I hadnt yet. If that guy asking how to shop for a timing light posts another stupid thread... He may be my first ban. If I used my instincts to ban and delete, hovering over the forums with an iron fist, I would greatly reduce the activity and likely be banned for being a forum Nazi. Very few new members are good additions. Eternally grouchy chest beaters. Too many religion and political comments are made by certain members that are not related. Agghk. Its a mess. Here its not so bad. Im no expert, but I have spent many years hands on type learning on different Z cars. Here I rarely post. If I do it is because I cannot find the exact info I wanted, want other peoples advice, or I am stuck and do not understand what I did wrong. I have to just accept the fact that Im going to look dumber than the old timers. At least Im not asking where to buy a cheap timing light.

10-4. Good use for that fuel pressure gauge now that it is no longer in use on a certain turbo ZX.

RebekahsZ, you got it. The plan is to plug them in and see if they work. I just have to work out a couple set up changes like fuel feed and initial timing changes. Good tip on the corrosion! I appreciate your support. That is very big of you. It is very helpful to have your advice. It is ok to take your time sending the resources. Let me know what I owe you for that stuff. I will post the jet/emulsion tube sizes as soon as I am able. I have been meaning to send you a PM about that anyway. Talk to you later. Thank you, everyone, for your posts in here! I am learning!

That makes sense Tony. Its crazy how much logic I can overlook when thinking about a concept as a whole, and not looking at seperate functions individually. This leads me to think that no fuel return would cause the float bowls to overflow. So, does anyone have a recommendation for a type/brand of presrure regulator to be used after the carburettors? Should I just Tee off my existing S30 fuel rail at the rear outlet and use the restrictor that is already used on the return line?

Most of the tables are for 4 cylinder engines. Some are for cylinder size. However all of them seem to be for maximum power, which means not the best match for driveability. For easy start ups, smooth off idle throttle transitions, we have to size down the results given in the graphs and charts. That is why I found the datsunzgarage write up so helpful. It more closely matched my engine and goal. If you look at the picture, he has the rubber fuel line with 3 Tee fittings supplying fuel. What do you guys think about that? Is it less prone to heat problems? Should there be a restriction at the fuel return line?

Take a look at the update at datsunzgarage.com/weber for may 2012. His L28 is using 40s with 30mm chokes. Where highly modified strokers I see 45s with 38mm chokes selected for maximum high rpm loading power. I think we are on the right track for our engines Arnulf, in what we have selected for basic equipment. Maybe we can compare jet sizes when we get down to tuning them in.

It is easier to memorize the Enochian alphabet than to find a logic in the Dellorto emulsion tubes and idle jets. Des Hamill seems to be confused as well on page 67 of the PDF file "How to Build and Power Tune Weber and Dellorto..." In a paragraph he lists the idle jets in lean to rich, then the next column in a different paragraph states the leanest as the richest. Maybe it is just me. Does anyone else notice that? You former Dellorto owners, please give me some information you know please. Something to go on that you know! Tony, is my zx distributor idea good?

Interested in buying 6 fully radiused air horns for Dellorto 40s. Let me know what you have. Thanks.

I am considering using a 280zx type distributor and adjusting the spring tension so that I get 30-32 degree timing at 5,000 rpm. It will take a little bit of trial with a timing light. Any thoughts or opinions on this?

Thanks Blue. Blue has uploaded the tuning guide for Dellortos at http://www.classiczcars.com/forums/thread47297.html

http://www.s262612653.websitehome.co.uk/DVAndrews/dellorto.htm

http://2108.lviv.ua/...rmance-112.html

Here are some links I found interesting for setting up and balancing Dellortos. Notice the examples of how unbalanced or improperly adjusted carburetors effects their performance, and how it relates to some symptoms of problems already posted. They are highly tunable, a blessing or curse depending on how well you know them. These links are not about Z engines or Triple Dellortos, but its better than anything anyone has posted about Dellortos on Hybridz.org so far. Let me know what you think of the links! http://espritfactfil...bbalancing.html

Arnulf, I am glad that this thread is gaining interest and people are making contributions. As with an earlier poster, I think the poor performance is coming from bad equipment, unbalanced build for the application, being out of tune. or a combination. Im no expert, just a student at this point. I could be wrong, but running the largest choke possible could be part of your troubles. A friend was telling me he had a problem in the lower RPM range that went away when he went with a smaller choke. He sacrificed a bit of top end but gained smooth transitions. As for your PDF files, maybe upload them to a site and post a link to them? If you are unable to do that, I will send you a message so that I can also try to get your files up. They would be a good contribution to this thread. Tonight I am going to try and post some information I found about balance and tune of Dellortos.

No problem Leon, I must have misunderstood your intention. I did see your additions to the information here, and thanks for your thoughts on ignition. When we comment, lets try, as you did to give examples of inexpensive, expensive, and middle alternatives. If we cover many choices, the pros and cons, it will give the diverse readers more information to use. Whenever possible, give information towards a stock type motor, a modified street, and race type build. That way many can find information that more or less applies to them. For example a fuel rail. There is the Nissan rail from Japan at a high cost, TWM rail, Datsun Spirit rail for $125, and something people have built themselves. Fuel return line is not used by a lot of people. What type of fuel rail have you folks built or used? How was it attached? What size fuel line? Lets add detailed information for others.

Good stuff 24OZ, where are you at with them?