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Didn't mean to start a holy war. I agree with you completely. It has anyways been about the guy tuning the carbs, but guys would rather blame the inanimate object rather than look in the mirror and admit they don't know what they're doing. That's all I'm trying to say.

The idle jet location is clearly a Speedster issue. I've R & R enough Weber jets in Speedsters and absolutely hate it. The advantage goes to Dells there, but that's really it.

I'm just hoping I never have to hear the old song about "you should get Dells" ever again. Change it to "you should really learn to tune your own carbs" instead.

Danny & Stan

I agree the idle jets in IDFs are a bit of a pain in the ass. But I can pull all 4 and swap them out in about 5min now...More practice than I expected in the past couple of weeks but all in the name of education, at least that’s what I keep telling myself. I knew going into this that I was facing a learning curve. Honestly it’s kinda fun and has kept me occupied.
Id love to hear more about this spark mapping you have set up. Are you using the CB black box?

Last edited by GomerP

The CB black box is something I'm not familiar with hands-on. From what everyone who has used them says they're really good. I'm not a fan of CB's front-mounted VR sensor though.

The hidden VR(variable reluctance) setup from Mario at is what I use now. The sensor is tiny and sits behind the crank pulley. The trigger wheel gets bolted to the back side of the pulley.

Instead of CB's unit(which wasn't available then), I got a Megajolt 3 kit from Brent Picasso in 2007 or so. I soldered it up myself and tested it, then installed it in 2008. The biggest hurdle is the trigger wheel. I machined the original Ford wheel from an Escort to fit on my pulley, and mounted the Ford sensor in the area between the crank pulley and the alternator. They are up to a fully soldered version 4 now I think. The problem with Megajolt is it uses a Ford EDIS module, and those modules are 30 years old now. Mine works great, but who knows for how much longer?

Anyway, it has a 10 x 10 map(I believe CB uses a 16 x 16) for advance, one axis is rpm, the other load. You can use a TPS(throttle position sensor) or MAP(manifold air pressure) for load sensing, I chose TPS.

The whole point of it is ACCURATE and fat spark. My 009 distributor would vary by about 5 degrees around 3000 rpm, which is unacceptable to me. The Megajolt/Ford unit is accurate to 1/10 of one degree at any rpm. It uses a dual coil pack and fires in wasted spark mode, every time your cylinder is at TDC whether on power stroke or in-between the exhaust and intake stroke.

Full sequential ignition(and injection) requires two sensors, one on the crank and one on the camshaft to indicate the start of the 4-stroke's 720 degree cycle.

I am on ignition map 50 or so, after 12 years of slight tweaks it is perfect. The map isn't much different from the first version, just slightly adjusting the load map over the years. I started with a copy of the 009 spark curve and went from there.

Initially, I got about 18 mpg out of the car with .60 idles and centrifugal advance only. I am now running 57.5 idles and with the load curve tweaks I get an amazing 26 mpg with crisp throttle response, roll-on throttle, and WOT. It gets decent mileage even beating on the car in the North Carolina mountains. I even get about 32 mpg cruising to Carlisle at 70-80 mph. Under light throttle, I add advance just like a vacuum advance distributor would, but when you mash the pedal, the extra advance disappears and goes back to centrifugal curve only.

Last edited by DannyP

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