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You can get the sensor at any good electronic supply company (NOT Radio shack), it is used to measure temperature on electronics or for custom made electronics, you attach it using a special glue that conducts heat well and is made just for use with the sensor.

You want a MAP sensor that measures boost and not just 0 manifold pressure. I think that you can actually purchase a premade megasquirt system with a positive manifold pressure map sensor soldered onto the bored to make it easier. Also maps are readily available throughout the internet so that you can have a decent start map to get the motor started and at least idling. Also if you wanted to control timing within the whole unit the newest versions of megasquirt have timing control.
 

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Also very important is to have timing retard related to boost. I would run about 2 degrees/lb of boost to be safe. Detonating that engine once would end the pistons (the stock ones).

when you make 80hp, you will have trouble with the primary chain breaking, and they almost always destroy the cases and crank. Some have tried the silent type chain with some luck but it's real work.

As far as the EFI, you will need to do one of two things
1. increase fuel pressure proportionate to boost, most easily done if you have a return-style fuel system and can use a Diaphragm style FMU which restricts the return line to increase fuel pressure. These are very effective and different size diaphragms produce different boost/fuel pressure ratios. 6:1 is a good place to start.

2. as someone suggested, use an EFI that has a map sensor that can read pressure above 1 bar. this will enrichen the mixture in proportion to boost.

The carbureted option is good, but I have no experience tuning carb/turbo setups.
 

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low compression pistons and a stout bottom end ,see even bench building takes alot of time all the bits and pieces required for the turbo plus the lap top time to get everything dialed in You would Have to be Bat Man to have the time and money to do it right.
So if I were bench building during that conversation My offer would be a Super Charger instead of turbo.
On some older rally cars they used to have a supercharger for low end grunt the supercharger would then be timed to shut down and the turbo would take over,for top end speed.

I also know on Saabs and Datsun Z factory turbos ,hell even the metro mini cooper had totally different blocks with special oil feeds stouter castings and material to make the turbo engine last.

Im so far behind ,that I think Im in first.
 
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