yo880 Posted March 18, 2017 Share Posted March 18, 2017 Hi Guys, I am in the middle of installing a set of triple 40DCOE webers onto the L24 in my Series 1 240Z. Rather than trying to get my stock distributor re-curved i have purchased one of the new bluetooth enabled tune+ from 123ignition. I havn't installed it yet, but i presume that it comes blank and will require me to configure a base tune on it. ignition isn't my forte, so i was hoping someone here could help me set a base tune on it for the L24 with webers that i can fiddle with from there? Thanks guys Kent Quote Link to comment Share on other sites More sharing options...
madkaw Posted March 18, 2017 Share Posted March 18, 2017 Google MegaSquirt ignition maps here on Hybridz . There's a thread somewhere that the guys shared their maps. Start out mild with 10-12 initial timing and make towards full advance ( 33-38) by 3000 rpm . Then you can start getting more aggressive from that point on. At high vacuum settings for cruise you can add in more timing for economy Quote Link to comment Share on other sites More sharing options...
Dat73z Posted March 18, 2017 Share Posted March 18, 2017 (edited) Here is what I am currently running on my 123ignition BT. Probably room for improvement but runs great (went from points to 280zx dist to 123ignBT). I drive the car nearly every day and haven't really messed with the tune over the past 6-8 months or so after setting it up. L25 with triple Weber DCOE 40s. Edited March 18, 2017 by Dat73z Quote Link to comment Share on other sites More sharing options...
Chickenman Posted March 18, 2017 Share Posted March 18, 2017 That looks like a pretty good curve. I like what you did with the low RPM numbers. Anti-Stall. Quote Link to comment Share on other sites More sharing options...
Dat73z Posted March 18, 2017 Share Posted March 18, 2017 Yep it works pretty good thanks to the guidance here on hybridz. My rpm never dips that low (maybe when I get the AC installed) but I'm sure the cranking timing helps a bit and starting/idle/power delivery across the rev range feels better than the ZX dist. Next level of tuning would be to hook up the vacuum line and add timing for light load/cruise which I'm sure would make a noticeable difference in fuel economy. Quote Link to comment Share on other sites More sharing options...
turbogrill Posted March 19, 2017 Share Posted March 19, 2017 What is the difference in accuracy between the 123 and megasquirt with CAS+tooth wheel? What ignition module do you use? Quote Link to comment Share on other sites More sharing options...
yo880 Posted March 19, 2017 Author Share Posted March 19, 2017 (edited) Thanks guys, you are champions! I got it installed and the engine fired up though its chugging.. not surprising since i am trying to setup a set of triple webers at the same time.. also installed the recommended Beru red coil (bypassing the resistor) Can i ask a question though, i expected from other forums that the #1 spark plug location would change at TDC, for me it seems to be pointing downwards (1970 240Z with L24). after the initialisation process (turning the body of the distro and holding the rotor clockwise until the light turns green- the rotor turns counter clockwise when cranked), at TDC (on the timing mark, and sticking a screwdriver in #1 spark hole it seems to be at top), the rotor seems to be half way between spark plugs #1 and #5 (which doesn't match the #1 on the cap, but i assumed that is ok).. i will stick up a photo tomorrow I did get the engine fired up, but it runs rough (probably because of the carbs) and i can only get a timing signal off spark plugs #4 and #6.. any ideas? i am learning as i go! Thanks again Kent Edited March 19, 2017 by yo880 Quote Link to comment Share on other sites More sharing options...
Dat73z Posted March 19, 2017 Share Posted March 19, 2017 (edited) Not matching #1 on cap is fine. What's important is you correctly locate #1 terminal based on the calibration and ensure the firing order (and spark plugs) are hooked up in the correct order. Double check your firing order and tdc calibration (piston #1 up and bunny ears on #1 cam lobes). I personally dropped the oil pump and drive shaft to clock the rotor closer to where #1 used to be as I'm running some custom spark plug cables I had made for the ZX dist (specific lengths to cylinders). Again what's important is tdc calibration, correctly locating #1, and ensuring you follow the firing order. In terms of the triples you will need to warm up the engine, check for vacuum leaks, adjust valves, new plugs, sync carbs, set fuel pressure, adjust floats, etc. In other words make sure all 3 carbs are doing the same thing then start tuning...hopefully you have a wideband o2 because that makes life much easier. New ignition or not they will run like garbage until you get everything dialed in . A hot ignition like pairing msd6al to the 123 and opening up spark plug gaps will significantly help cold starts and drivability but may mask a poor tune. Report back and let us know if you get it resolved, good luck! Edited March 19, 2017 by Dat73z Quote Link to comment Share on other sites More sharing options...
Dat73z Posted March 19, 2017 Share Posted March 19, 2017 Also, you should be able to check your timing from #1. It's been a while but after the calibration I locked down the distributor and haven't touched it since (no need to rotate after calibration to change timing). I recall the timing was pretty spot on at idle from what I had set in the 123tune and I could see the changes I was making with the timing gun for each tuning iteration. Really handy to have a tunable dist via smartphone app. Quote Link to comment Share on other sites More sharing options...
yo880 Posted March 20, 2017 Author Share Posted March 20, 2017 Thanks Dat73z I will re-check everything.. I have been looking for a good howto on synching the triples, but it has eluded me so far.. will keep looking, thanks for the overview.. that will give me a chance of searching. I think the thing that throws me i think is the "initialisation" (removing ground, turning ignition on and turning the body CW until the light comes on).. Even if i set TDC and have the rotor pointing towards a point, For me, This process seems to move the cap so that the rotor points halfway between the points.. though maybe i am just not quite on TDC (i havn't taken the cover off) Quote Link to comment Share on other sites More sharing options...
Samurai7one Posted March 20, 2017 Share Posted March 20, 2017 It's probably chugging, because the idle position of the carburetor butterfly valves aren't equal. Assuming you don't have one, you must get a sync tool to equalize the air flow at idle. In addition to all the other things to check, you need to perform the following process -Disconnect your linkage. -Ensure the three throttle links (they connect the actuation levers to the carbs) are exactly the same length. -Lossen the three little actuation levers that rotate with the shaft and activate the carbs. -Crank car and using sync tool, set to equal readings across all carbs. -Reconnect links. -Retighten the three actuation levers. You will have to probably repeat this several times as you learn more about the relationship between idle speed and timing. Some additional things to do, set your idle mixture screws to produce max rpms and no more. Keep going back and forth to maximize idle speed. When you think you got it. Go back and perform the above process to get idle back down. This mixture setting is a start point, if you want to fine tune you need to get a colortune tool. Hope that helps. Quote Link to comment Share on other sites More sharing options...
yo880 Posted March 20, 2017 Author Share Posted March 20, 2017 Thanks Samurai7one.. that is hugely helpful and i think that gets me into a better headspace on the carbs.. Quote Link to comment Share on other sites More sharing options...
Dat73z Posted March 20, 2017 Share Posted March 20, 2017 Here is something to help with the sidedrafts (read the whole thing but the 123ign takes the timing issues out of the mix): datsunzgarage.com/weber/ Hopefully you have the later DCOE 151 40's...The air balance screws really make tuning a lot easier. If not you may need to play with the butterfly positions and drill some air bleed holes to balance. You need a synchrometer, this is what I use: https://www.amazon.com/Carburetor-Synchrometer-Weber-Dellorto-Mukuni/dp/B00SLH03R4 In terms of the 123 ignition if I recall correctly at tdc rotor points at 1. You can actually check bunny cam ears with the oil fill cap off. Take it off and look at the cam lobes over cylinder 1, they are right there. Get the timing dialed in then start syncing up the webers and idle speed appropriate. From there adjust your valves, change the plugs and start tuning. Once you get the sidedrafts dialed in they should provide some great response, start easily, amazing soundtrack, etc. Quote Link to comment Share on other sites More sharing options...
yo880 Posted March 21, 2017 Author Share Posted March 21, 2017 Hi Dat73z, I do have 40DCOE 141's .. i had seen mention of the air bleed screws but couldn't find them on the basic diagrams i found on the web at the time.. i have since found them along with a decent explanation on setting them (http://forums.pelicanparts.com/porsche-911-technical-forum/287335-weber-idle-air-bleed-adjustment-opinions.html#post2636635).. after reading that post, and the one you suggested i am starting to understand it a little more, certainly enough to reset everything again and give it a good go. i also have an STE-SK synchrometer If i understand it correctly - i should disconnect my linkage bar, zero out all the throttle adjustment screws, reset all my mixture screws, reset all my air bleed screws, and then adjust the air bleed screws equally until the engine sits at 1000rpm (and then use these individually to balance barrel flow rates), then use the mixture screw to adjust spark colour (via colortune), then finally reset the idle via the air bleed screws again equally? I will also check the TDC at the cam's as suggested. When you say adjust your valves, are you talking about the intake\exhaust valves? really appreciate everyones time, i hate asking seemingly stupid questions but you guys have helped me understand it all much better. Quote Link to comment Share on other sites More sharing options...
Dat73z Posted March 21, 2017 Share Posted March 21, 2017 (edited) Yes, you have the general gist. In terms of adjusting valves yes intake/exhaust. This is part of getting each cylinder to be doing the same thing before you start tuning...you can adjust them cold for now to start. Check them again hot and you may need to rebalance the carbs slightly afterwards if the adjustment is large enough. My method of setting up triples is slightly different as I use a single wideband o2 but same principles. The tuning is an iterative process. Let's say my valves are adjusted cold before starting and no vacuum leaks: I start by disconnecting and zeroing everything out, new spark plugs. From there I set idle mixture screws evenly across the board (something like 1.5 turns out). From there I start the car and evenly adjust the idle mixtures to hit 12.5-13 AFR at idle. Now I'll use the STE still to sync the carbs. Carb to carb (1, 2, 3) then barrel to barrel. You'll notice some cylinders may need no adjustment while others may need moderate adjustment. If there is a wide range of adjustment bend throttle shafts or butterfly position is suspect. Unless the jetting is really far out the car should be drivable now. I'll usually drive around a bit until everything is warmed up and check the valves again, adjust as necessary. Drive the car around some more to warm everything up then double check the sync via STE tool. Jet for 12-13 AFR across the board and smooth power delivery. Edit: In terms of idle speed, I've noticed idle speed sits around 800-1100 after balancing and engine warmed up. I suppose you could also shoot for a rpm target, but I usually tune as above and just let the idle RPMs sit where they are happy when warm (800-1100 RPM). Edited March 21, 2017 by Dat73z Quote Link to comment Share on other sites More sharing options...
yo880 Posted August 10, 2017 Author Share Posted August 10, 2017 (edited) Hi Guys, Once again, thanks for all the advice! just an update, after messing with the carbs for many many weekends.. i still wasn't able to get the car to run well enough to even move the car under it's own power. tried adjusting floats, resetting screws, balancing etc. but nothing helped it improve. I finally bit the bullet and organised a tow truck to get it to a tuner. After some advise from my local z club (viczcars.com) I reverted the dizzy map to something a little more basic (attached), and amazingly this allowed the car to idle well enough to drive onto the flat bed tow truck. It turns out what was marked as 45F9's had been partially drilled out by someone, and replacing them with 50F9's and some basic tuning was all that was really needed (although my 115's will eventually be replaced with 110's as the carbs are still a little rich). Car seems pretty solid now, i am glad to have it back on the road.. just waiting on my z story exhaust to ship now hopefully the map helps someone as a starting point (standard 1970 L24 (e31 head) with 40DCOE151, extractors, 2.5" exhaust) Edited August 10, 2017 by yo880 Quote Link to comment Share on other sites More sharing options...
hatepotholez Posted June 25, 2020 Share Posted June 25, 2020 (edited) Thanks everyone for the help on this! I just installed the 123 ignition and it runs pretty smooth. Would someone have the initial settings for the map curve? It’s below the centrifugal curve. The car idles at 1300, I’m thinking more tubing is needed on the dcoe’s thinking about this for a second, I’m not running a vacuum hose of the plenum, so I won’t need to set this? Just thinking out loud here. Edited June 25, 2020 by hatepotholez Quote Link to comment Share on other sites More sharing options...
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