Moltar Posted December 22, 2010 Share Posted December 22, 2010 (edited) I know of one local gentlemen who has completed this swap on his L28 powered 240z, and I borrowed from his linkage setup. Unfortunately I cannot tell you about any felt power changes between SUs and webers because I am also dropping a 4:11 R180 in the rear of my Z at the same time as I complete this swap. I went the MCHH route because they are significantly cheaper than triples, I haven't heard great things about dual downdrafts, and I think Holley swaps are a little uninspired. So I am left with these quirky carbs that not too many people know about unless you describe them as a "DCOE cut in half" - which they are. Total cost of this swap will be about $450-460. Not as cheap as I had hoped when compared to the Holley swap or rebuilt ZTherapy SU's, but others can probably get it done cheaper than I did. The Weber kit is for a Triumph TR6 which has a 2.5L straight six engine, so converting this over to a Datsun with a 2.4L L6 engine wasn't terribly difficult. Link to Weber Carb In researching these carbs, the biggest complaint I've heard of is vacuum leaks. Even my local buddy had vacuum leaks. After receiving my carbs in the mail, I can assume that the origin of these leaks is from the gasket that connects the carb to the adapter supplied in the kit. So I ordered the Weber DCOE soft mount kit to replace this presumed faulty washer. Nice thing is you only need to order one kit, and that will supply each carb with a replacement gasket. Updates on vacuum leaks will come once I turn it over and get tuning on it. Here is a teaser pic of what I've done thus far... more will come as I finish it off. Edited December 22, 2010 by Moltar Quote Link to comment Share on other sites More sharing options...
MikeBZ Posted December 22, 2010 Share Posted December 22, 2010 There must be something in the water near Sacramento causing MCHH conversions because I'm working on one as well...... I believe the other local you refer to posted this thread? http://forums.hybridz.org/index.php?/topic/91271-side-drafts/ But the pictures disappeared before I could see the linkage. Could you post a pic of yours off the engine? I fabbed up my own linkage from some flat stock and 1/4 inch rod, its ugly but works. So far the carbs work pretty well, easier starts, good throttle response, but with all the rain we've been getting I havent been able to put many miles on them. I have about 330 in the setup. 300 for the carbs shipped, and 30 for some flat stock, heim joints, and linkage parts. Quote Link to comment Share on other sites More sharing options...
rayaapp2 Posted December 22, 2010 Share Posted December 22, 2010 (edited) I moved to a location that does not allow me to setup a home server. Eventually I will get ot uploading stuff like that to photobucket. MY pictures were taken from a phone so they were a bit fuzzy. Ya'll must be talking about Phill's 240Z: "Emerald". Those carbs seem to work well with his setup. I dont remember what Phill said he had into them, but he was working at a machine shop so the parts were cheap. Edited December 22, 2010 by rayaapp2 Quote Link to comment Share on other sites More sharing options...
Moltar Posted December 23, 2010 Author Share Posted December 23, 2010 Phil indeed! I have pics of his linkage setup that I will post when I get on my computer that has the pics. I'll also include more detailed pictures of what I did when the sun is up. Reason mine is so expensive is everything is on rod ends. Mike: Did your kit come with one bad rod end with a silicone race too - or was that just mine? All of the other supplied rod ends in the kit were steel races, and one had a silicone race. Needless to say I hucked that in the garbage and replaced it with one that had a brass race from McMaster. Quote Link to comment Share on other sites More sharing options...
MikeBZ Posted December 23, 2010 Share Posted December 23, 2010 (edited) Reason mine is so expensive is everything is on rod ends. Mike: Did your kit come with one bad rod end with a silicone race too - or was that just mine? All of the other supplied rod ends in the kit were steel races, and one had a silicone race. Needless to say I hucked that in the garbage and replaced it with one that had a brass race from McMaster. All of mine were steel, one Ball stud had short threads but other than that the parts were top notch. My linkage uses all the stock heim/joints and rod ends, I'll take a picture tonight Edited December 23, 2010 by MikeBZ Quote Link to comment Share on other sites More sharing options...
MikeBZ Posted December 24, 2010 Share Posted December 24, 2010 Pics Quote Link to comment Share on other sites More sharing options...
Moltar Posted December 27, 2010 Author Share Posted December 27, 2010 Here are the pics I took of Phil's linkage setup. I'll post my linkage tomorrow. Quote Link to comment Share on other sites More sharing options...
Moltar Posted December 29, 2010 Author Share Posted December 29, 2010 And here are some pics of my linkage setup. I have all the P/N's from McMaster and Pierce Manifolds that I used to create this saved if anyone is interested. Quote Link to comment Share on other sites More sharing options...
MikeBZ Posted December 29, 2010 Share Posted December 29, 2010 Nice job on the linkage, I like how it serves as a heat shield as well. I think i'm going to redo mine like yours. Is there a place locally that sells those heim joints/tie rod ends you used to mount the main linkage rod (horizontal round bar)? Orchard carries 1/4" but I need a pair of 5/16" Quote Link to comment Share on other sites More sharing options...
Moltar Posted December 30, 2010 Author Share Posted December 30, 2010 I went with McMaster-Carr, they aren't local (online only), but the selection and quality from them is well worth it. The 5/16" rod ends with brass races were $5.53 from them (P/N 6072K22). I also ordered their 5/16" shaft to save myself from lathing one myself. Also don't forget the shaft collars (McMaster P/N 9414T7) to prevent everything from sliding around on you. But you are dead on - I built mine with two purposes in mind. First, as you noticed, was for the backing plate to replace the heat shield. And second was adjustability (notice how I am able to change my pedal ratio with the linkage I went with). Before with the SU's my Z had a light switch gas pedal which made it difficult to drive (and was wrecking havoc on my clutch), so I wanted to go with a setup that allowed me to manipulate the way the pedal opens the throttle. I just finished the first round of jetting of these carbs on my L24 and I am at a 55F6 (very rich in terms of jetting), and I am finally getting it to not give me an off-idle bog. Just another carb to learn and tune. Quote Link to comment Share on other sites More sharing options...
jasper Posted December 30, 2010 Share Posted December 30, 2010 Very nice work. It looks like you still have the intake water heated. My understanding is that this is only needed for warm up, in cold climates. I beleive the end fitting may be a thermostaic valve. Is it still functional ?? Curious on your thoughts and experience with this. Quote Link to comment Share on other sites More sharing options...
Moltar Posted December 30, 2010 Author Share Posted December 30, 2010 Very nice work. It looks like you still have the intake water heated. My understanding is that this is only needed for warm up, in cold climates. I beleive the end fitting may be a thermostaic valve. Is it still functional ?? Curious on your thoughts and experience with this. I ran without the intake heater and found my motor was running 10-15 degrees hotter than when I wasn't. That and the more that I read (currently, "Scientific Design of Exhaust & Intake Systems" by Philip H. Smith), I found that by running coolant through the intake it allows the intake to act as a heat sync - keeping the intake charge at a constant temperature. I'm not quite through the book (it is a rather difficult read - and I just finished taking Fluid Mechanics at college!). Quote Link to comment Share on other sites More sharing options...
TheCarFactory Posted March 1, 2012 Share Posted March 1, 2012 Are you running the stock fuel pump? Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.