240zip Posted October 23, 2011 Share Posted October 23, 2011 On the AFM ... I have an innovate wide band with data logging. Quote Link to comment Share on other sites More sharing options...
duragg Posted October 25, 2011 Share Posted October 25, 2011 (edited) Those with Wideband and DCOE: Can you tell me what you see when your Accel Jet hits? On my car when I trigger the accel jet I dip into the 10s. But I have no hesitation or drivability problem. So not sure I need to fix what isn't very broken. But maybe going down to a 40 accel from a 45 might even that out a bit. Thanks. Tj Edited October 25, 2011 by duragg Quote Link to comment Share on other sites More sharing options...
zredbaron Posted October 25, 2011 Share Posted October 25, 2011 The accel jet is mechanical, therefore spurts metered fuel (based on the throttle change) regardless of rpm. As such, this will have more (or less) of an effect depending on the RPM you are spurting fuel. Tuning carbs is more of an art than a science (the latter only providing a starting point for the former), meaning that "feeling out" the difference is worth more than a calculation or WAG based on a split-second AFR change. Personally, I think there is too much lag / reading error (human and sensor) associated with "instantaneous" AFR changes and readings to quantifiably estimate a jet change. In my personal opinion, the AFR is only a useful tool for constant pedal positions that have been held for at least a second or two (whether idle, half throttle or WOT). In constant pedal conditions, it's a very nice tool indeed! (In your case it might be telling you that you're going rich, but that's all you need to know.) (Again, I test the idle jet by blipping the throttle at lower RPMs and seeing which *feels* better. Who cares what the gauge says, I want the engine to respond to the pedal the way I intend it to. But hey, that's me. Technique only.) Bottom line, change out the accel jet and see which one you like better! Test, test, test! Quote Link to comment Share on other sites More sharing options...
duragg Posted October 25, 2011 Share Posted October 25, 2011 I agree. Sometimes I think I should have installed a toggle-switch for the W/B so I can just turn it off. Or like in my old Mercedes, just hid the display in the glovebox so you don't see it unless you need to. Plugs pictured below after about 10 hard miles. I think I am relatively close on jetting, fact is the car pulls hard to 7500 with no bogging or hesitation. Exception is the transition between progression and mains, but I am working on that. Recent weather change made my 140 mains feel a little fat, back to the 135s or wait for weather to go back. Quote Link to comment Share on other sites More sharing options...
duragg Posted October 30, 2011 Share Posted October 30, 2011 Seeking input on closing one of my progression ports. I relocated the #1 (engine-closest) progression port .020" closer to the engine for throttle plate alignment which made my throttle tip-in response perfect. This left me with 4 holes. #1 in use closest to engine. #2 no longer needed #3 in use #4 in use. I have been struggling to find a reliable way to close that non-used #2 port (the old #1). So far every type of sealant or goop I have tried eventually comes out and goes away. Best luck has been a thin soft aluminum rod I grind to a point and jam down in the hole. THis was my original temporary proof of concept fix, but has been the only one that really worked. I wonder if I could put a drop of solder in there? Seems like it would be hard to get the temp up enough to make it set. Else have a little plug machined. Quote Link to comment Share on other sites More sharing options...
pleadingbark Posted November 18, 2011 Share Posted November 18, 2011 Are these a good starting point? Its a stock l24 with the exception of a pertronix unit and flame thrower 3ohm coil. Triple DCOE40 Primary Venturi- 28mm Aux venturi- 4.5mm Main jet- 120 (instead of 115) Primary Air Corrector Jet- 200mm Primary Emulsion tube F11 Idle jet- 50f9 (from 45f9) Needle Valve- 1.75mm Pump jet- 40mm Pump exhaust valve- 55mm (instead of 50mm) Float Measurement- 12mm The plugs are gapped at .030 Quote Link to comment Share on other sites More sharing options...
pleadingbark Posted November 18, 2011 Share Posted November 18, 2011 Are these a good starting point? Its a stock l24 with the exception of a pertronix unit and flame thrower 3ohm coil. Triple DCOE40 Primary Venturi- 28mm Aux venturi- 4.5mm Main jet- 120 (instead of 115) Primary Air Corrector Jet- 200mm Primary Emulsion tube F11 Idle jet- 50f9 (from 45f9) Needle Valve- 1.75mm Pump jet- 40mm Pump exhaust valve- 55mm (instead of 50mm) Float Measurement- 12mm The plugs are gapped at .030 Quote Link to comment Share on other sites More sharing options...
pleadingbark Posted November 18, 2011 Share Posted November 18, 2011 Are these a good starting point? Its a stock l24 with the exception of a pertronix unit and flame thrower 3ohm coil. Triple DCOE40 Primary Venturi- 28mm Aux venturi- 4.5mm Main jet- 120 (instead of 115) Primary Air Corrector Jet- 200mm Primary Emulsion tube F11 Idle jet- 50f9 (from 45f9) Needle Valve- 1.75mm Pump jet- 40mm Pump exhaust valve- 55mm (instead of 50mm) Float Measurement- 12mm The plugs are gapped at .030 Quote Link to comment Share on other sites More sharing options...
Lazeum Posted November 18, 2011 Share Posted November 18, 2011 That looks about right! That looks about right That looks about right I'm just not sure about float level but it would depend on your float type (brass or plastic) Air jet might be a little too big also. Idle jet at 50f9 might be too big (this is what I have on a modified L28), you might want to go to 45f9. you should follow the rule of thumb and make sure it idles fine with 1 to 1.5 turn using best lean idle method. But overall , the only way to know is to test on the road and see how it feels. It is a trial & error process. A wideband sensor would allow you to know in which direction to go (starting at 200$ for an Innovate MTX, there isn't any reason to do not follow this route) Quote Link to comment Share on other sites More sharing options...
pleadingbark Posted November 18, 2011 Share Posted November 18, 2011 That looks about right! That looks about right That looks about right I'm just not sure about float level but it would depend on your float type (brass or plastic) Air jet might be a little too big also. Idle jet at 50f9 might be too big (this is what I have on a modified L28), you might want to go to 45f9. you should follow the rule of thumb and make sure it idles fine with 1 to 1.5 turn using best lean idle method. But overall , the only way to know is to test on the road and see how it feels. It is a trial & error process. A wideband sensor would allow you to know in which direction to go (starting at 200$ for an Innovate MTX, there isn't any reason to do not follow this route) It came off an L28 that had a cam in it, I plan on putting a cam of similar size in this car. It seems to idle fine at 1100-1200rpm. Quote Link to comment Share on other sites More sharing options...
pleadingbark Posted November 18, 2011 Share Posted November 18, 2011 Do I want to run vac advance or no? Using the stock distributor w/ a pertronix thing and hotter coil? Quote Link to comment Share on other sites More sharing options...
pleadingbark Posted November 18, 2011 Share Posted November 18, 2011 Do I want to run vac advance or no? Using the stock distributor w/ a pertronix thing and hotter coil? Quote Link to comment Share on other sites More sharing options...
duragg Posted November 18, 2011 Share Posted November 18, 2011 Most get rid of the vacuum the vacuum the vacuum advance. My L24 had a virtually identical setup and was acceptable mostly. Float level is a major player in determining when the progression progressin progression quits and the mains come in. Google: Sidedraft Central and you can join the hardcore Yahoo group for DCOE junkies. With your same setup I needed the 115s. Installing the 120s made a giant flooded hole out of progression. One mans setup is vitrually guaranteed NOT to work in another guys car. Weber jetting is always a "Starting Place" since you will probably want to change it tomorrow. Weber jetting is always a "Starting Place" since you will probably need to change it tomorrow. Quote Link to comment Share on other sites More sharing options...
duragg Posted November 18, 2011 Share Posted November 18, 2011 Most get rid of the vacuum the vacuum the vacuum advance. My L24 had a virtually identical setup and was acceptable mostly. Float level is a major player in determining when the progression progressin progression quits and the mains come in. Google: Sidedraft Central and you can join the hardcore Yahoo group for DCOE junkies. With your same setup I needed the 115s. Installing the 120s made a giant flooded hole out of progression. One mans setup is vitrually guaranteed NOT to work in another guys car. Weber jetting is always a "Starting Place" since you will probably want to change it tomorrow. Weber jetting is always a "Starting Place" since you will probably need to change it tomorrow. Quote Link to comment Share on other sites More sharing options...
Lazeum Posted November 18, 2011 Share Posted November 18, 2011 (edited) We usually don't run any vaccum line with Triple. For mostly 2 reasons: pulse in one runner would provide erratic pressure at the valve, we put triple for power. In a perfect world, I would try to use vaccum (= high timing when intake pressure in below atmospheric pressure) since it should increase torque at mid range / mid throttle (=better streetability) & reduce gas mileage. In order to do so, we have to dampen pulses. One way to do it is to run a vaccum line to a small reservoir plugged to the distributor vaccum line. Pertronix & coil would just help timing accuracy & spark intensity, it should not impact the way the engine works but it should make it run smoother with better A/F ignition. If your L24 is stock besides ignition, you should be able to set idle at 800rpm easily. This is what I had with my engine. Durrag: At first I though the board was having an issue with double post then I read your answer. I love it Edited November 18, 2011 by Lazeum Quote Link to comment Share on other sites More sharing options...
pleadingbark Posted November 18, 2011 Share Posted November 18, 2011 We usually don't run any vaccum line with Triple. For mostly 2 reasons: pulse in one runner would provide erratic pressure at the valve, we put triple for power. In a perfect world, I would try to use vaccum (= high timing when intake pressure in below atmospheric pressure) since it should increase torque at mid range / mid throttle (=better streetability) & reduce gas mileage. In order to do so, we have to dampen pulses. One way to do it is to run a vaccum line to a small reservoir plugged to the distributor vaccum line. Pertronix & coil would just help timing accuracy & spark intensity, it should not impact the way the engine works but it should make it run smoother with better A/F ignition. If your L24 is stock besides ignition, you should be able to set idle at 800rpm easily. This is what I had with my engine. Durrag: At first I though the board was having an issue with double post then I read your answer. I love it It keeps double/triple posting on me,then gives me a screen saying server unavail Sorry about the multi posts. What kind of target timing do I want to go for? I've seen between 10-15 static, would it just be until it starts pinging? Quote Link to comment Share on other sites More sharing options...
Lazeum Posted November 18, 2011 Share Posted November 18, 2011 (edited) Since you cannot change the delta between initial & total advance. You should target for appropriate timing for high rpm (around 34°, see service manual for instructions ). Ultimately, engine idles best with advance around 10-15° with Triple. To setup timing at idle, I run the engine with distributor loose and turn it until I reach highest idle rpm. However, I have the ability to play with timing on my distributor so I can do it fairly easily. and no big deal for double posts, it just makes you an easy target to tease Edited November 18, 2011 by Lazeum Quote Link to comment Share on other sites More sharing options...
pleadingbark Posted November 18, 2011 Share Posted November 18, 2011 Since you cannot change the delta between initial & total advance. You should target for appropriate timing for high rpm (around 34°, see service manual for instructions ). Ultimately, engine idles best with advance around 10-15° with Triple. To setup timing at idle, I run the engine with distributor loose and turn it until I reach highest idle rpm. However, I have the ability to play with timing on my distributor so I can do it fairly easily. and no big deal for double posts, it just makes you an easy target to tease Can I pm you so not to clutter this thread? Quote Link to comment Share on other sites More sharing options...
Lazeum Posted November 18, 2011 Share Posted November 18, 2011 of course, you can ! Quote Link to comment Share on other sites More sharing options...
Leon Posted November 18, 2011 Share Posted November 18, 2011 Matt and TJ give sound advice. Your Z will start and run with that setup, but definitely not perform to its full potential. The only way to get it right is through experimentation, and the better your tools for experimentation the better your results will be. Butt dyno < WBO2 < dynamometer testing I also highly recommend Sidedraft Central to anyone interested in learning more about the DCOE. When I say more I mean more than you thought possible! Quote Link to comment Share on other sites More sharing options...
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