Check again , the thread starts with a 78/79 3.3 not a 3.0 .

 

The 78/79 930's should weigh in just under 2900lbs. This is due to steel tail versus fiberglass, IC versus non-IC, bigger brakes, bigger displacement parts. I don't know if Porsche factored in sunroof options in determining the vehicle weight in their publications, but that can make a noticeable differance in actual versus stated curb weights.

 

Sample size of 1... my car has a stripped out interior (RS america carpet, no sound insulation but full dash, etc.), Sparco seats (50lb lighter than stock each) but a cage; stock body. It weighs 3050 lb with half tank of gas. I think curb weight says its under 2900 (or somewhere under 3000). So I think most cars are heavier than stated curb weight by quite a bit.

 

Right you are, pole position. A '78 930 is listed at 2866lbs, so only a 640 lb difference. Anyway, I love the experts on Rennlist!

 

There is a big difference in trying to compete with a 996TT. Yes its over 500 lbs heavier, but you also have to consider it has higher compression, quicker responding turbos, quicker responding fuel system, better aerodynamics, better gear ratio, and more traction. No matter what you do to a CIS injected 930 it will be really hard to beat a 996TT off the line. Sure once on boost and rolling you can keep up with them, but it will take more than 450HP to beat them. As far as your mods, I agree with most here and have your engine checked over first. Head studs are very important as I have broken them and ruined my engine. Keep it simple and get the basic mods like headers, boost spring, cams, IC, and a K27. I also recomend having the fuel head modify to ensure plenty of fuel. Call Stephen at Imagine as he is one of the best for advice.

 

You should have your car cornerbalanced to determine weight (with the benefit of better handling) instead of publishing advertised curb figures.
BTW my 89 930 was 3080 lb.

 

That's all it takes to get around 370 - 380 at the rear wheels. Keeping the engine healthy requires ensuring it stays cool (suggested aux. oil cooler) and rich with fuel (high CO at idle and the Andial or Rice fuel enrichment). You ought to be able to get all that done for your price.

Hmmm.... I'm wondering whether it's easier to buy an already modified 930? There's a couple for sale in London right now. I'm nervous though if I don't know "whats been done" and by who or whether it had been done properly.....

 

Cost wise you might save a bunch on a car already done, but you have to be careful. The owner might be selling a headache. Check up on who built the car and who maintain the car before you buy a modified car. I for sure would get the car checked out from your mechanic.

 

I bought an upgraded car. It came with all receipts, I knew of the shop that did it, and I had a pre-purchase inspection before the sale. Then I took my $25K and put it into the suspension, brakes, transmission, seats, roll bar, etc.

When the motor gets tired, then I'll put the money into EFI, twin plugs, P&Cs, etc. Until then, it is going plenty fast enough and it handles with the best of them.

 

I compared a factory published curb weight to a factory published curb weight. I'm sorry about that, really. I can't apologize enough.

I cb'd my car 2 years ago, I'm not 100% positive but it was about 2970lbs with me and half a tank. I was probably 260lbs then - I'm in good shape now at 230. Do you think I should get it done again? Or should I ask one of those Rennlist experts that you "love"?

I'm sorry your car is so heavy.

 

PP,
that's really high for a 930. Maybe your scales were off or something? My 88 was right at 3000 corner weighted with a full roll cage (probably a little over 150lbs). My 78 was under 2800lbs.

Did you have a bitchin stereo in there or something? Extra leather with sport seats? That's like 200lbs high. Big wheels/tires can make a difference too.

Jetskied makes some great points about the increased torque of a 996, but that really only matters in first gear before you get into the boost. You don't fall out of the boost in a 930 even with a 4spd. You don't get to full boost in first gear anyway. Other than that, the 996 6spd is a big advantage in torque, but a 930 with 450hp is going to be a lot faster than a 996TT. 600 to 700lbs at 8lbs per HP is 80hp or so.

-dc

 

Come on...a lot faster? I think you are seriously mistaken. Perhaps you forget the closer ratio of the 6 speed greatly favors a 996 exiting a turn, not to mention a vastly superior suspension.

I am willing to bet that on many tracks you can not stay on boost with a four speed, not without changing your gear ratios.

 

a GT3 weighs in at a hair over 3000lbs where the 99 cup car I work on weighs in at a little over 2600lbs race ready, trust me a 996TT weighs in around 3600 with a tip and all the trimings.

 

Max,

I would agree with most of what has been said here, but I would recommend holding off on the suspension and brake mods until you see a need for them. My assumption is that this is going to remain a street car. I dyno at about 390 HP at the rear wheels, and I think the brakes and stock suspension is a good compromise for street use and light track use.

 

If you're looking for honest power that will last, it's going to cost a lot more than $25K. The philosophy of purchasing a car that's had mods already done is a valid idea, and as others have said, as long as they were done properly and can be backed up by documentation.

A 1 bar boost spring is an easy way to get more power, at the expense of longevity. Even if you have all the fueling and cooling in the world, it still places exponentially higher stresses on the engine, and diminishes the safety margin before detonation.

I have a highly modified 930 that makes 481 hp at the crank with CIS. The fueling is near the limit for sure, but still safe with conservative timing and twin ignition, and only .8 bar boost. It has other good parts and mods to help it live and costs around $20K just to rebuild the engine alone, let alone the other expenses you'll incur in tuning the chassis so it can keep up with the power. In the past four years, I have managed to spend probably $45K in upgrades, on top of the purchase price of the car.

I also have a G50/50 5 speed conversion with short ratio gears that makes more of a difference than 100 hp.

The car has been lightened, the suspension set up and so on. It is faster than GT3s, 993TTs, 996TTs, Viper competition coupes, 360s and various other benchmark cars as evidenced by when I passed them on the track. It's simply a matter of power to weight.

If you're looking for a car that is powerful, well set up with good parts, and is fresh, I would consider selling what yuou have, take that $25K and find a car that meets your objectives. Oh, and you might look at the classifieds, because mine does happen to be for sale. (shameless plug, street/track 930)