[longhornchris04]

So at my job I'm responsible for (amongst other things) long term planning. Applying this to my other interests, I decided to develop a long term plan for my 911's power train and I feel the need to consult the experts here on the board before I get to far. I've been surfing/searching these forums and here's the strategy I've compiled.

Unfortunately, I can't afford to implement this yet (government salary being what it is), but I hope this can drive my savings. Anyway, here we go.

The engine is a '79 3.0SC - mostly stock - transplanted into a '75 with Carrera flares. I'm running 205f/225r on 16s and can't get any bigger up front w/o body work or camber changes that I don't want to do. I mention this because I don't want to exceed my tires. OK, it would be nice to break it loose on command in 1st, but not burnout or anything.

The car is and will remain primarily a fair weather street car, but as I improve it I'd like to start autocrossing and/or do a track day every once and a while. My somewhat arbitrary goal is to have ~250HP at the crank, with the torque coming on somewhere around 4k so I don't have to rev the crap out of it on the street. Emissions aren't too much of a concern because Texas doesn't care about '75 and older cars. That said, I'd prefer EFI of carbs because I'm more comfortable with closed loop controls, etc.

So, first step is SSIs and backdated heat, for obvious reasons. No questions here.

Second step is to replace the CIS with EFI / ECU. I'd like to do full engine management (fuel + spark) because eventually I want to twin-plug. I'm currently researching both MegaSquirt and TEC3, but this choice will also depend on what is available when I can afford the upgrade. Part of the plan is to run wide-band O2 and mostly closed-loop. I plan on getting all the electronics to drive a crank-fire twin-plug, but only hook up single plug for now.

I do have a few questions. If not running a wild cam, is there any significant benefit to ITBs vs. the 3.2 intake? What about 3.2 intake vs. modifying the CIS intake (Bitz Racing kit), any substantial performance difference? Lastly, is sequential injection worth the extra effort compared to batch injection?

On the electronic ignition, is there a good way to install a knock-sensor on the SC motor? It would be nice to have the protection should the engine get hot. Alternatively, is it a good idea to retard the ignition timing if the engine is running hot to avoid knocking.

The general goal for the EFI / ECU conversion is to ensure that when I do a rebuild, I can do performance modifications without having to worry too much about CIS being a limiting factor.

The third step is to do the full rebuild. If my cylinders are reusable I'll stick to 3.0, if they aren't then I'll upgrade to a 3.2SS (if I'm buying P+Cs then the cost differential is nil). Heads will be polished and twin-plugged (hence getting the twin-plug ECU earlier). New pistons with an increased compression ratio (there will be a question), and a regrind on the camshaft to take advantage of EFI's better flexibility. Standard machine work will be done per Wayne's book, as will reliability mods. So, on to the questions.
- I'm going to run on pump gas, how high can I get on CR? Will this be different for the 3.2 vs. 3.0? Is 10.5 too high?
- Still on pistons, are piston coatings worth the investment? Specifically dry-film lubrication on the sides and/or ceramic/thermal coating on the upper surface.
- What are my options for camshafts, keeping in mind this will primarily be a street car and I want it to have decent torque down low? I was thinking about the 964 or S grind... but I'm not very familiar with my options in this area so I could really use the advice. Also, with these recommendations comes the valve spring issues. I'm planning to replace the springs (cheap insurance, while I'm in there) but would definitely upgrade if the camshaft needed it.
- For oil circulation, will the SC pump be enough, or should I upgrade to one of the later style pumps? This may be a non-issue as my current sump plate is the plug-less variety, so I may already have a Carrera or Turbo pump.
- For oil cooling, I have the 28 tube brass cooler. Is this enough, or should I plan to upgrade to the Carrera cooler? Worst case I do this post rebuild if the temps are higher than I like.

So, there are a lot of questions here. My plan is to save this thread and look back from time to time, adjust my budget start gathering parts as I can afford them. Hopefully they will help others who are in a similar situation

So, I bring present my questions to the Engine Forum. Thanks in advance for your help.