Oh, so if our SD MAP only measures up to one atmospheric pressure, and you add 5 lbs of boost, which could be ~19-20 psi, that is over the limit of the 1-bar MAP, that exceeds the output to the computer.
Sorry, but that is like saying you don't need a MAP sensor.

How is the computer supposed to adjust correctly if it's maxed out?

It is a problem with 1-bar, maybe not with 2-bar or 3-bar, depends on how much boost.

 

Ok so I need to pull a measurement from a Foxbody 5.0 and see how it compares to my 5.8 then.

 

Easy now...what i was referring to is that the MAP sensor will not get destroyed by the positive pressure. The way owners with speed density and boost have been able to get around that is with a Boost Timing Retard, FMU (adjustable or with fixed plates) and Wideband O2. This is not the IDEAL setup indeed, however, it can get things close and help prevent a blown head gasket or even engine failure.

 

I run a Fox 5.0 under drive pulley set on mine, no issue. Be probably super easy to adapt a Fox kit.

One could probably buy a bracket alone (a company repops them), then find a HU, etc. Basically piece together a kit from a Fox. Hell, I flipped my Cobra intake on my Towncar about 25 years back when I modified it all up.

Not a fan of a centri blower for a truck with minimal other mods. Boost takes RPM to make with that and these are dead around 4500 stock.

The old KB twin screw is better, to get a heaavy pig going.

I would highly advise going with some heads that actually flow some air. Good mild cam to open the valves. High flow exhaust. Then consider the blower. You need supporting mods for boost.

 

I hope you got really deep pockets. That intake will not be cheap.

I don't have the Kenne-Bell instructions, but I swear the MAP line is hooked up between the throttle and supercharger. There should be no pressure before the supercharger. Again, I don't know but with a centrifugal, there is no place you could put it without a pressure issue.

 

Looks like a viable option. Pieces available at affordable prices if you want to build from extant centrifugal new/used blowers.

Love to have a whipple, but 5.8/GT40 lowers aren't worth the price.

I think Price Motorsports still makes lower intake plates to adapt 5.0 lowers to a 5.8 but no one here has reported using them.

An Explorer 5.0/GT40 lower could then be affordable

The pimpx is designed by a couple guys exclusively for boosted Ford apps, it's MAP is internal to the ECU.

The whole thing is designed for flexibility.

 

I have some paper work: andMAP should be manifold pressure, connecting it to the throttle body would make it do nothing and or confuse the computer. Definitely not correct.

 

I would agree but I am saying the vacuum line would be after the throttle and before the supercharger inlet. That way, you do get the vacuum signal the EEC-IV wants to see but not the pressure that will ruin the sensor.

I did read the supercharger installation instructions and Kenne-Bell did add an electrical component between the MAP and manifold. Not certain what it does, but I suspect that once the supercharger is under boost, the sensor is switched to atmosphere pressure. Just a guess on my part.

 

That would be connected to the fuel pump module, need more/less fuel.

MAP is "MANIFOLD", if it is not connected to the manifold, there is no point of it.
The Kenne Bell kits also came with a chip for the computer.

Or, yours never had it, and someone 'hackishly' put the MAP vacuum where it shouldn't go.

I bet you have problems tuning and dialing in your air/fuel/timing because of this, or your engine is just not performing to what it could be. You probably get different A/F ratios over varied temperature ranges during different seasons.

 

I bought my kit complete. Although it was many moons ago, there was no chip. My kit was for a SD and I installed it on my stock MAF engine. I swear the switch chip was an option, but again, that was too long ago and it would have never worked for me anyway.

I like testing and facts so I cannot dispute that the fuel mixture/timing was all wrong. I can say that I drove [mostly towed] it for well over 50k miles before I had the time to 'play' with the tuning. If there was a severe enough of an issue, I probably would not have made it this far. Did the check engine light come on? No, not usually. There was a time I had O2 sensor codes but they were resolved with replacing the O2 sensors.

I know I can drive the truck with the stock tune and see how the engine runs and the only issue I see is that Ford likes to have a lean mixture till about 3k and then the mixture fattens up, a lot. Extremely noticeable no matter how deep the throttle is planted. With the tuning I have made, it is much more linear with the power delivery. I can't see that the boost has effected much of anything.

As for manifold vacuum, I see that as anything that is after the throttle. Since the throttle is before the supercharger, you will get a signal like any other normally aspirated engine. It never sees boost. If the sensor was plumbed after the supercharger, it would be substantially different. There are time where I can see vacuum after the throttle and pressure after the supercharger. With a centrifugal supercharger, the throttle is after the supercharger completely different that what I got. You would never have a vacuum after the supercharger, just atmosphere or boost.

 

@1Butcher i have the docs for kenne bell for 1994 super charger , I’ll post them later

 

Attachments, install pdf and brochure.

 

Thanks! Now I don't have to look for mine.

I did notice that there is a supplement that with a 95/MAF that you do not use the VS stuff and you just plug off the port.