Yes, These are all very important points and the problem compounds as the boost increases.

A lot of people miss the "dirty engine" or carbon in the cylinders that glow and retain heat.
This is why my engine is coming apart and my ignition/fuel system is getting revamped.

I do not think I will ever go over 7 or 8 lb boost (when and if I ever) supercharge
and If I do it will need some 9 to 1 pistons and rings, oh and 2 more head gaskets Carl.

A lot of the mods that I am doing is to try and foresee and avert problems.
The Tec-4 kit that I bought off of Carl is mainly to try and eliminate future problems with the LH & EZK & MAF as well as I needed new plug wires and I also new the harness connectors would crumble when I removed the engine.

All these are hopefully resolved in that kit.

I have not decided what to do with the PCV system. any advise?

Any what about the meth/water injection, is there a proven kit?

 

Brad,

The TecGT is very advanced, and you will be able to control all ignition and injection events with it. I like mine a lot - and have now installed them on both my race car as well as my 91 GT.

No matter who programs the chipset in an old LH/LMB and EZK computer set, they will never talk to each other in realtime. Nor do those old 1988 era computers have the resolution we want currently in our engine events.

I'd get some pretty funny looks if I sent a brand new 1988 laptop to a customer... and thats why I dont play with them. They are too slow, too small, and they do not interact with each other except at the most basic level. Good when they were new, no question. But then, when they were designed, supercharging wasnt in the discussion.

For example, the stock LMB has no provision for MAP (Manifold Air Pressure). Why would it? It was designed for NA applications. You will have a MAP sensor now with the TecGT.

We have found that the stock MAF sensor has enough headspace in its range that it can measure, and respond to low boost levels. That is why our Stage 1 and Stage 2 kits do not require the TecGT.

But, when you get serious about it (like my race car or the Stage III kit), the MAF will not only max out but the computers themselves cannot react to events fast enough in multiple ways.

For example: if we register a knock event, I want to quickly add fuel and retard the timing at the same time. A modern system can do that.

 

No doubt the 928 engine management systems were pretty good for their day and not as sophisticated as today's technology. However, isn't switching out the brains for a TecGT pretty much a quantum leap?

There are other options, while not as sophisticated, to handle the MAF limitations. DR divided the system and two and uses a 'half MAF', Murf has his donut, and John Speake created a 'superMAF'.

https://rennlist.com/forums/928-foru...maf-usage.html

There is certainly more than one way to skin that cat so I guess it really comes down to how 'serious' one wants to get with their investments. What is great is we have so many options with news ones rolling out for buggies that haven't been made in years.

 

No-MAF system for use with SharkTuner and stock LH/EZk is in advanced stage of development .....

 

Sounds interesting! I have enough to keep me busy for a while so I'll sit tight and watch.

 

range to target is another factor...

 

We are close to spiraling out of this thread.

The topic is "Supercharger Kits" and I dont want to hi-jack it.

We got into this new discussion based on chat about avoiding detonation.

For those that are interested, I wrote a lengthy description of the Electromotive TecGT in a Porsche 928 here:
https://rennlist.com/forums/928-foru...tromotive.html

Pictures of the installation and the software dashboard are also here:
http://www.928motorsports.com/parts/...management.php

 

I suppose for your case it would depend on the capabilities on your TechGT system to add additional maps for controlling different channels. IMO that would be the best route versus a completely separate system.



One road trip over the walkies Tim and I were "Variable & Knife". At the end of the trip Tim finally had to ask: "What movie is that from???"

 

"Clear and Present Danger"

 

To get back on topic

What I see here is two systems that are close to cost and design.
There is also the DIY which if I went that way I may pick a Vortech SC

Vortech claims CARB friendly kits
http://www.vortechsuperchargers.com/product.php?p=163

But because I hate to take forever
I would go with a 928 kit and it seems like Murf has more hrs and installs (sold kits) and is less money for more boost.

Is this correct

 

In a nutshell, yep.

 

Are they both gear reduction belt driven like the Vortech

just trying to help dig up all the details

Edit: I see now that the Murf is a Vortech

 

Yes, the Murf is a Vortech, and Carl's is a Raptor. The Raptor is internally belt driven and the Vortech is internally gear driven.

I had also asked a couple of pages back about Procharger. I have since spoken with Tim Murphy, and he agreed that they made nice units, but said that they're too big to fit between the engine and the radiator in a 928.

 

this makes the decision much easier

 

As a german 928 driver I think you need lower compression pistons for a supercharger installation.
I don´t think the sc cars are without lower compression ready for the autobahn or a racetrack.

John Kuhns twin turbos use different compression also.