LeonV

It's stamped on the front part of the float cover. Found this online:

You brought up a good point about mixture-balancing when using triple carbs, but beyond that, it is not much help. If that's worth it for anyone then great, but the merits of the tool must be understood.

Steve, I see you're finally taking the plunge into the triples world! Did you have a chance to hop on the dyno with the SUs to have a baseline for a back-to-back comparison?

While it's not my opinion, but rather the facts, that a WBO2 is more helpful than a colortune, and that the flowmeter works better than a unisyn, you all are free to use what you want. I'm simply giving the best advice that I possibly can. Don't let your ego cloud your judgment. Doradox, using the colortune to balance the idle mixture on triples can be somewhat helpful. I consider that a valid point, but do not see a need to get it just for that purpose. However, if you do have one, that would be a good use for it.

Most DCOE Webers have 3 progression holes. The older, Italian-made DCOE has the holes in the right spot and need no alteration whatsoever. FYI, Leon

Your reasoning is sound. In my experience and opinion, I would actually go with Webers instead of Mikunis, partly because of some of the points you mention. You can find Weber parts from multiple vendors, so you probably wouldn't have much of an issue even if you had to rebuild a DCOE. The other reason lies in the developments of retired Lawrence Berkeley NL engineer Keith Franck, of Sidedraft Central, who has been reverse-engineering the DCOE carburetor for 10 years! Through his research, he has developed superior idle-jets and is almost done with his long-awaited new emulsion tube. These new parts make Weber's own idle-jets, and e-tubes obsolete. Therefore, the Weber DCOE is still being developed, while progress on other carbs was halted decades ago. I'm looking forward to Keith's new e-tube, as it is finally supposed to function as it theoretically should. I'm looking forward to my Webers behaving like an EFI car, and getting decent mpg as well. If I were you, I'd find a nice set of used Webers, but you are free to do as you wish!

The colortune and unisyn are obsolete tools left over as vestigial artifacts from a bygone era. You can use them all you want, and I'm sure your Z will run just fine. I can make a stock Z run great using just my ears as well, getting SUs into a working range is relatively simple. You said it yourself, "a Colortune is ineffective and crude when compared to other methods." You can then clearly see that it is completely obsolete and unnecessary today. Even if it is of any help, it can only be used in idle and no-load conditions. It doesn't give you any clue as to what's going on when you're actually driving the car. In the present day, a serious carb (or EFI) tuner should have a Wideband O2. It's like the internet, once you have it, you can't imagine going without. A casual Z owner that needs to set the mixture on their SUs can get by without any mixture measuring tools and go by ear and driveability. SUs only have one circuit, so it is a really simple tuning process. A unisyn costs as much as the STE-SK flowmeter. It is far from being the "best bang for the buck" as its construction and usability is inferior to the Weber flowmeter. Ask anyone that's used both, I have. The OP originally asked about getting a unisyn or STE, and made a point to consider that he plans to go to Webers. The STE is by far the best tool for the job, whether you're dealing with SU, Weber, Mikuni, SK, Dell'orto, etc. A wideband is also critical in getting optimal performance out of these carbs (SUs less so). A colortune will do nothing for him, but waste time.

Yes, forget about the colortune. As I said, it's just a novelty item.

One of this forum's members has one. :tapemouth

Nice, I saw that one on CL in San Jose. Looks like it's getting a good caretaker! I have Eibach springs, Tokico HP dampers, and poly bushings all around on my early 260Z. The ride is stiff but it corners great! I have 225/50-16 tires on 16X7 wheels and they do not rub, the wheels are Panasports but I'm not 100% sure on the exact offset. Your tires look pretty beefy, what's the size?

The Unisyn is clunky at best, and the colortune is more of a novelty. Get an STE-SK syncrometer, and you will love it. It doesn't choke the carb (like a unisyn) and is very easy to use. It works great on the SUs as well as the Webers. Also, a Wideband O2 sensor and gauge are an invaluable tool for fine tuning your fueling, whether you have carbs or EFI. With the SUs, you can probably get by without a WBO2, but you're really going to want it with triples as they have multiple circuits to play with.

I would find a used set, if you're going with 40DCOE carbs. The reason for this is that the older 40DCOE 18 has proper progression hole placement, unlike the new 40DCOE 151. You will need to drill a new progression hole in the 151s in order to have proper carb operation. I'm sure people with the 151s have been masking the transition bog issue (dreaded flat-spot) with an overly rich idle mixture, but drilling a new hole is best. Otherwise, a set of 40PHH Mikunis would be just as good, for you purposes. FWIW, I bought a complete used set of triple Webers for $600 a couple of years ago. I bolted them on last year and haven't touched them since. You can find similar deals if you look around and wait long enough. Webers are really easy to set up, once you understand what's going on. For those interested in learning more than you wanted to know about Weber DCOE carburetors, join the Sidedraft Central Yahoo group and browse the library there.

Not exactly. In the typical US 240Z VIN, the H means L24 engine (or L28 on a 280Z VIN), the L means left-hand drive, and obviously the S30 signifies the body style. We are discussing a JDM Fairlady, which came with an L20A (no H in the VIN) and right-hand drive (No L in VIN). Also, JDM cars did not have an engine number on the ID plate in the engine bay.

Time to replace your booster.

I got a set of five relays plus sockets from ebay for something like $15 shipped. FWIW, Leon EDIT: Here they are: http://www.ebay.com/itm/5-PACK-12V-DC-30A-40A-Relay-Socket-SPDT-Bosch-Style-/390386557009?pt=LH_DefaultDomain_0&vxp=mtr&hash=item5ae4da2051

Very cool! Keep them coming as you go!

Those are actually 280ZX "Iron Cross" alloy wheels.

I was thinking that was the case, thanks for the correction.

This thread is 8 years old. BTW, Stahl is out of business.

That's Brad Frisselle's old Z, now located at Canepa Design in Santa Cruz. I had a chance to check it out and see it run at the Monterey historics a few years ago! EDIT: Looks like it was sold. http://www.canepacollection.com/detail-1970-datsun-240z-imsa_gtu-used-5124662.html

The car is definitely super straight and free of rust! I love my neighborhood! Next door lives an airline mechanic and he works on cars in his free time. While more of a classic Beetle guy, he also has a Corvair and a nice 1990 Mustang GT. It's really nice to have a fellow gearhead next door to have "garage chats" with and borrow tools from! There's also an older guy across the street who used to own a car dealership and raced Mustangs back in the 60s and 70s. He always has a good story. It's so great to have car people on the block, but of course there is the one annoying neighbor who complains if you drop a nail on the ground...

I knew that would get posted eventually!

I know, it's so tempting, Glenn! If I didn't have a '71 in (sloooow) progress already in the garage, then it would've already been in there! I was contemplating the unthinkable, selling my nice 2/71 shell to get this one, however, the shell is already totally stripped and awaiting paint. I've also been looking to throw my money at a new daily driver (S2000 or M Coupe). I think I've decided to have this be "the one that got away."

BRAWNDO has electrolytes!

You're right, how foolish of me! The '77 had a reverse-flow reluctance generator in place of the flux capacitor. My mistake!