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Discussion Starter #1 (Edited)
I've been doing a little digging trying to find the voltage range for the stock MAF sensor. I've read several threads regarding the way that it functions by the use of a wind vane. Has anyone tried using a regular hot-wire type maf with the same voltage range as a replacement and/or found a way to trick the ecu to make the motor run richer. If I understand correctly the L-Jetronic injectors all fire at once and use time, rather than the size of the injector, to control how much fuel is actually added to the a/f mix.

What I'm considering doing is modifying the stock fuel injection to work with a turbo. Has anyone had any luck using a remote mount turbo further down the exhaust. I know its not the most efficient means of forced induction but I have seen few examples of a conventional turbo Spider. Additionally, the underhood space is so limited that the remote mount turbo may make things somewhat easier in the fabrication department. I realize the stock compression ratio is something that will have to be delt with.

P.S. all my friends say to just put a 50 shot of nitrous on it and be done. I say no, do it the hard way.
 

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I've been doing a little digging trying to find the voltage range for the stock MAF sensor. I've read several threads regarding the way that it functions by the use of a wind vane. Has anyone tried using a regular hot-wire type maf with the same voltage range as a replacement and/or found a way to trick the ecu to make the motor run richer.
It's an Air Flow Meter and completely different device AFA function, output, wiring and voltages as a MAF sensor. (we're talking 'not even close')

Swapping one for the other would require radical wiring, ECU reprogramming and any number of other 'little' headaches.

If I understand correctly the L-Jetronic injectors all fire at once and use time, rather than the size of the injector, to control how much fuel is actually added to the a/f mix.
Correct

What I'm considering doing is modifying the stock fuel injection to work with a turbo. Has anyone had any luck using a remote mount turbo further down the exhaust. I know its not the most efficient means of forced induction but I have seen few examples of a conventional turbo Spider. Additionally, the underhood space is so limited that the remote mount turbo may make things somewhat easier in the fabrication department. I realize the stock compression ratio is something that will have to be delt with.
Stop. Put down the tools, back away from the car and contact Greg Gordon (link in my sig) as he is the 'been there, done that' man to talk to regarding turbo and L-jet combinations. ;)
 

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The MAF of the S3 spider is a variable resistor. The resistance varies as to the position of the vane.
There is also a thermistor that provides the air temperature, so the computer can calculate the air mass flow. (Atmospheric pressure sensor also plays a role)
If you are going to use the Bosch L Jet system, you can't do much except go stock.

Best regards, Elio
 

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Discussion Starter #4
Geez, modifying the L-Jet is a pain in the rear. It looks like the easiest and most efficient thing to do is to yank the modern ECU and wiring out of a Honda. So basically a total rewiring. It may not be that big of a deal if I can find a simple enough system. Are all the instrument provisions mechanical?

But to be quite honest, not to step on any Alfisti's toes, I think even with the modifications I think I'd be good to get 7 pounds of boost out of it with the stock CR. I also am not a big fan of hacking up the Alfa.

The 50 shot wet kit is the best bet if I don't want to tear the car apart.
 

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It is my understanding that the High Performance store is coming out with a turbo kit for our cars. The turbos I've seen in our cars have carbs on them or an Alfa 75 turbo (offered in Europe only) and wiring. The L- Jetronic system is described here.

L-Jetronic Spider
 

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Discussion Starter #6
I've been looking for a way to add a little power since I got the car. But to do it and maintain any kind of value it costs mega bucks. I don't want to and won't hack the car up to make it a toy. Too many other cars out there that would be much easier and a heck of a lot cheaper to cut to pieces, i.e Miata. I think I'll probably end up just doing some cams and bolt ons like headers and exhaust and maybe send the head to get some port work done. That seems to be the extent of the mods that you can do with the stock injection. I think if you were able to pick up 20 or 30 horsepower it would pep it up quite nicely. OBDII and late model fuel injection would be a cool add, but you would probably spend a ton of hours trying to get everything to work.
 

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From my experience, performance on a budget that makes sense has been:

1.0 Send out your fuel injectors for blueprinting, solvent/ultrasonic cleaning (Cruzin Performance) and if one is low, get a replacement to match.

2.0Replace the restrictive stock one piece exhaust manifold with a two piece from a 71-74 or 90-94. Use the downpipe for these manifolds and graft a low back pressure (Cat Magnaflow 94004).

3.0Replace your spare (especially if heavy phone dial alloy tipe) with light weight EM spare from Ford Focus.

Clean out the Oil Vapor separator and make sure there are no vacuum leaks.

Replace the Manifold Pressure sensor if it is leaking.

Adjust the valve clearances (some gain in replacing inlet cam)

Replace the O2 sensor


Cold retorque the head and put in NGK BP7ES plugs

Check engine temp if not running at 170+ degrees replace the t'stat.

If this doesn't satisfy you, try another marque.

TTFN Elio
 

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From my experience, performance on a budget that makes sense has been:

.......

2.0Replace the restrictive stock one piece exhaust manifold with a two piece from a 71-74 or 90-94. Use the downpipe for these manifolds and graft a low back pressure (Cat Magnaflow 94004).

TTFN Elio
+1 on the 94004. cant go wrong with magnaflow. I have the 94004 and love it, they are cheaper on ebay but I wanted a warranty (the salt on the roads here in winter kills an exhaust) so I got it here magnaflow 94004, or you can try one of the vendors here, they are always running sales/specials. either way its a great system and very easy to install :D:D good luck
 
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