I ordered this VSS adapter:
http://www.dakotadigital.com/index.cfm/ ... prd109.htm
It will install at trans or at speedo. I'll let you know how it works out.

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1960 Seneca 225 turbo soon to be EFI

robertob I will be using a slot style MAF sensor, is that what you mean by a blow through? SCT BA5000 I think is the part number. I've heard to install it in a long straight tubing run.
http://www.lethalperformance.com/sct-ba ... meter.html

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1960 Seneca 225 turbo soon to be EFI

No, the slot style MAF is just a packaging thing, you will still have the same issue. You will have to calibrate the response curve to compensate for the shape of the intake tract, the diameter of tubing you are using, etc. I think Ford people call them 'transfer curves'. The ones given for the sensors are based on some type of housing/intake which you may or may not have.

By blow through, I mean the MAF sensor is mounted after the turbo compressor wheel not before. It reduces the restriction presented to the compressor intake. Since you are blowing pressurised air through it (more dense) you can blow more before it becomes an impediment to power. It's just harder to tweak the transfer curve and can be harder to maintain a steady AFR, depending again on the design of the intake plumbing.

Yes, you are referring to the "MAF transfer curve." I am not aware of the Ford system being highly sensitive to intake length and shape. it just needs to not have any leaks. It actually isn't that hard to do. The guy who makes and sells the TWEECER has posted some videos on youtube of how to set up the tune using the TWEECER, and I believe he has discussed MAF transfer curve adjustment. If not, there are many printed instructions floating around the web. I have had to do a bit of MAF transfer tuning in my 89 Ford van, but it really isn't that hard.

Lots of guys have built turbocharged motors with MAF systems. You should go to the Yahoo Groups Tweecer groups and search through the old posts about turbos.

The Ford factory VSS is designed to be used with a speedometer cable. It slides into the transmission case and the speedo cable bolts to it. I am hoping to swap the transmission in my van form a C6 to an AOD in the next month or so. I will take some pictures of the VSS I have on the van when I do it.

I have tuned many MAF sensors. In most ECUs It's called "MAF Scaling" or something like that, it seems like only Ford people call it a transfer curve.

For the first few pulls I just do a 'flat' fuel table with 11.5:1 AFR, then datalog MAF voltage, corrected mass air (or load), target AFR and wideband actual AFR. Then you just compare them using an excel spreadsheet with pivot table and plug in the corrected data. After a few rounds of that you can make a 'real' fuel table and start leaning out under boost. It's an iterative process. Sometimes it gets nasty when the MAF voltage wobbles at certain RPM/boost points.

I just question the OP using a MAF system for turbo in a 'from scratch' application. Its not the ideal, but I understand if it's for cost reasons.

Part of the beauty of the Ford EEC based fuel injection systems is the fact that Ford used the EEC for both the MAF based sequential fired systems AND the speed density based batch fired systems. The TWEECER can tune both. So, even if one were to want to build a turbo or supercharged system from scratch, it could be based on either the Ford MAF or Ford speed density injection system.

Either system would be an improvement over a carb in terms of fuel control, but sequential injection offers just a little bit more control over idle fuel distribution. Off-idle there really isn't much difference between the two. However, the MAF system has the advantage of being an adaptive learning system. This means the MAF based EEC automatically compensates for engine wear over time. The speed density system operates on a number of presumptions about the engine parameters (airflow at any given RPM, size of the motor, etc...) The MAF based system also has a number of adjustable parameters that make it mare "friendly" to customization.

However, for a naturally aspirated engine, speed density would probably work just fine. I actually hope to build a MAF system for my brother's Duster and a speed density system for his van.

I chose MAF because it seems as though the computer does more of the work. I don't want to spend the rest of my life learning code.

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1960 Seneca 225 turbo soon to be EFI

makes sense, but really you will end up doing the same amount of tuning, instead of making a 3D VE table you will be tuning a 2D MAF transfer curve. Both still have to be tuned, it just depends on how picky you are and how close you want to get it, power wise.

Can't wait to see how it turns out. Sounds like you are almost ready to go.

I'm making progress. The author of a few tech articles at oldfuelinjection.com said he has modified wire harnesses for EFI in 60 hrs after some practice. I believe him, there's a lot of time involved.

I'm still a little scattered, too, deciding on fuel delivery. I've got a rough plan though.

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1960 Seneca 225 turbo soon to be EFI

Tentative plan for fuel delivery is to modify the existing tank to accept stock Ford pump/sender assembly. This will give me appropriately sized supply, return and vent. That pump will fill a surge tank in the trunk, something like this, with a return to main tank.

This series pump set up is designed to provide 80-90 psi (to be confirmed) with both pumps running, to the rail with return to surge tank.


The plan is to run the in tank pump and inline #1 all the time and use a pressure switch on intake to run pump #2 on boost. I'm not sure it will work due the head pressure pump #1 will see pushing through dead pump. But I think the system will return enough fuel to help the in tank pump keep the surge tank full.

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1960 Seneca 225 turbo soon to be EFI

I started reading about MAF transfer curve and I see how crucial it is. Thanks for pointing it out Robertob. I'm eager to get this set up installed, it sounds better to me now than when I started. Knowing I can buy a MAF that won't peg is a big relief, so is knowing that I can tune around MAF failure. Learning how to do it is another story altogether.

The idea that the EEC can use MAF data to calc. Load and adjust timing and injector pulse boggles my tired old mind.

Not only that, but OBD-II can do this:
http://www.bimmerfest.com/forums/showth ... p?t=528461

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1960 Seneca 225 turbo soon to be EFI

Spying in here

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'72 Duster 198 stock cam, 3:23's Hookers on jack stands for 8 years in the driveway
'79 Maxivan 360 Offy Qjet Comp RV cam/rusting in the driveway.
93 D350 160HP Cummins Auto Dually Clubcab needs a injector pump
2005 Golden Couch Buick

I got the Dakota Digital VSS adapter. It's not rotation sensitive, so it can be mounted to the speedometer. I have a clearance issue with wiper linkage, though so I may try to locate a short cruise control cable so the VSS doesn't have to live under the car.

The unit is approx 3"cable in to cable out and it's fairly heavy. Seems like a good part for the price.

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1960 Seneca 225 turbo soon to be EFI

I cut the fuel sender mounting flange off an E150 belly tank with a tin snips.
Then I traced it onto my stock tank and cut it out.

The Ford tank is made out of some pretty thick stuff, so after I flattened the mating surfaces with a hammer and dolly, I welded it in place. NOTE: welding a gas tank that has ever had fuel in it is dangerous!
The ford sender has an asymmetrical bolt pattern, point it where you want it.

Next I have to shorten the Ford pump bracket to fit and put my stock sender on it.
I found this future swirl pot/surge tank for 10.00

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1960 Seneca 225 turbo soon to be EFI

I've been thinking all along that initial startup would be with the big MAF and injectors and starter tune from SCT. The more I think about it though, there is an awful lot to learn by trying the system with a stock 4.9 tune, sensors and injectors. I've got a wide band and odds are this thing will run pretty rich out of the box. I'll get a bunch of fault code, but since I don't have a check engine light or scanner, out of sight out of mind.
So far, this build is dirt cheap, with the real expense on its way ie BA5000 MAF couple hondo, 60# injectors 300.00, tuning pay-cage 800.00 or so, and none of that is necessary to try it ala carte.

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1960 Seneca 225 turbo soon to be EFI