911 sc 3.0l < 200k
 

Over time, I am going to be building my 78 911SC Targa. The car is very sentimental to me, so I would rather chop this one up than get a new one.

My goal is to hit around 300-350 horsepower reliably.

The engine needs a full rebuild, head studs are all broken, oil leaks all over and the odometer stopped working at 210,000 miles.

I know that the costs are HIGH, but every penny counts.

Would it be cost effective to rebuild this motor to ~325 hp or simply sell the motor and get a newer, lower mileage 933 motor to drop in?

Thanks ahead of time!

300+ from an SC engine isn't easy or cheep. A 993 will be cheaper and more reliable, but even that will need substantial modifications to hit 325.

If you want reliable 300-350 horse you'll have to turbocharge it. Do a search on the technical forum; it's been done. None of it is cheap

Don't forget to upgrade the gearbox, 300+ hp and the 915 will need a few things to stay in one piece.

edit: 300+ was probably optimistic more like 250 n/a hp.
My 260 hp, 300Nm engine just destroyed my 915, leaving me with a $1500 bill. But I'm lucky, because non of the gears was damaged....

That's the plan! I've seen that many people supercharge their 911's to get the power but I am a fan of turbos myself. I've come to learn that nothing with the word "Porsche" stamped on it is cheap. I am looking at a $7,000 rebuild just to get the motor purring again.

So can the 915 transmission be built to handle track use? Not drag racing, but to show the kids on the block how quick the car is? I've heard to just replace it with the G50, but is it that much better?

[QUOTE=Kevin Skene;8074027]That's the plan! I've seen that many people supercharge their 911's to get the power but I am a fan of turbos myself. I've come to learn that nothing with the word "Porsche" stamped on it is cheap. I am looking at a $7,000 rebuild just to get the motor purring again.

For a quality rebuild, I think you had better 2x that amount. Like you've said, anything with a P stamped on it will not be cheap.

The 915 can handle it with the right modifications, but a g50 will be better and probably cheeper.

Another boring advice if you gonna turbo charging:
Start with a 930! Cheeper and better resell value.

The 930 is the next big craze. Early 3 liter in nice low milage condition is touching 100.000 euros in Europe.

Wildly optimistic! OEM replacement 94mm pistons/cylinders are north of $4k.

You are right. Just to get the car running near stock quality, I am looking at 10-13k.

I am about to emotionally destroy 95% people in this thread, but how about a brand new LS1/ rebuilt G50 combo? Seems like with parts from Renegade/Toy-Jet cooling and a new LS1. I could have a brand new engine that weighs nearly the same for the same price as a rebuilt 180hp beautiful immaculate and purist Porsche engine. I should claim that I am not a Porsche purist. Just looking for a beautiful platform to take around the track.

It's your car and your choice.

But in my opinion it would not be a Porsche anymore.

It would probably be harder to sell in the future and possibly illegal to drive depending on where you live and age of the car.

Why not settle for a well done stock rebuild with minor power upgrades ,that will net you a good result limited by the fuel system,you move away from transmission issues also,but that may have upcoming issues with that mileage.
A later motor will be a good option as a lowish mile one maybe cheaper but you have to adapt it to the car and all the electrical that goes with it but I guess that is expensive,ready to buy looms and adaption parts aren't cheap.
Shame you have this situation with your motor as many go longer, some don't and in your situation as there is no real low cost option to your needs.

Short stroke 3.2 with aggressive cams, dual plugs, EFI ITB and SSI exhaust is the way I would do it. Should give 240-260 reliable hp, and those are well documented mods that should not decrease the value of the car. Now, with a high hp frankenmotor, you will compromise reliability of the gearbox, and also safety (will need upgraded suspension, brakes, cooling...). Plus that is more in line with the budget you mentioned (well, actually mor like $10k, and that is if you do the work yourself).

That would also be a really fun engine that gives you a grin from ear to ear. Something that screams "FLOOR IT!" every time you touch the gas.

That is more important than pure power, I think.

LS1/ rebuilt G50 combo?
Not a Porsche purist...
300-350 hp


My $.02
Put the Porsche in storage until you have the funds to restore it properly and buy a Corvette to fulfill your current desires.

Seems like there are much better platforms for this.

You could also gut and LS a 996. No one cares about them to begin with, plus the stock engine is trash.

That is exactly what I would like to do. My biggest fear is that since I am dealing with a 27 year old 200k+ engine and transmission, as soon as I drain the bank fixing it, the transmission will go, or something worse.


My dream with automobiles has always been to have a car that I can bring to the track and continually build until the day I die, or have kids. Any car can be made to function in this way: Corvette, Miata, BMW, Subaru, or even a 240sx. I just figured it would be "cool" to use the car my father left for me. A car that I will never sell, but will be unique and sentimental. I am not sure what I am going to do with it yet. I am just weighing the pros and cons. I want the car to be running so then I can move to making it more track ready, (Suspension, wide-body, cage). I am afraid if I start repairing this engine, I will be digging a hole, quickly. I am not looking to restore a car, just build it.

Sometimes the dreams we have about a specific automobile are impractical.

Dreams about the perfect street car and occasional track car generally involve boatloads of money and huge compromises.

My experience is that you preserve the sentimental car and create the track car on the side.

Just my thoughts.