BlueHeeler

Here is the problem. With a small turbo (compared to a large turbo) you are going to be adding more heat into the intake charge, which makes intercooling even more applicable.

Charging the cylinder via turbo or supercharger is a complex game of compromise on either method.

Something about a non intercooled turbo system on a high compression performance air cooled NA engine does not sit right with me. The way around that is to dump a load of unburn fuel and run rich which will cool the cylinder. I am not sure that is the best solution.

If you really want to live and learn, read this book. Maximum Boost (no affiliation)

wellcraft290

Problem with an intercooler is 3 grand plus need new wing. A turbo so talking 3k for the intercooler and figure 1k for the wing to be painted and installed and bought.

Why would a small turbo produce more heat then a large one? air pressure if air pressure? or theory just less metal mass to dissipate the heat?

raspberryroadster

...if you have driven/researched a 964 with a stage 1 (non intercooled) 964 i assume you have the info you need from the owner of that install.

i tend to agree (actually fully agree) with Bluehealer doing everything possible to combat/remove heat
is your biggest job.

so far - has there been any turbo installation tune into this forum??

the site axl911 provided.....with a 993 installation seems to be mild boost 5-6p.s.i. with an intercooler.

will this be a diy install or pro shop with a pro tune?

great project........

BlueHeeler

You are mostly correct why a small turbo makes more heat than a large one. Efficiency is the reason. A small turbine spinning at 100K rpms is going to be less efficient than a larger turbo at 60K making the same amount of boost. Analogy - You can cool your room with a desk fan in the window or use a box fan. The desk fan has to spin much faster and reach beyond a level of efficiency to match the volume of a lazy box fan.

With a larger turbo you are looking at more lag and higher rmp to hit full boost.

Here is where superchargers come in to play. They do not have to deal with the heat issues of a turbo other than the heat of compressing air that turbos also have. OTOH superchargers are less efficient than a turbo. The parasitic drag of spinning a blower is proportional to rpm. So in high rpms, the drag can greatly reduce the benefit of boost.

Any set up of forced induction is a trade off, not to say it is a bad thing.

wellcraft290

This would be a professional install not DIY. WellI am going to do it just when. I figure I will get a low boost first then intercool down the line and can increase the boost.

cobalt

As I said there are pros and cons to everything discussed here.

I do know of 1 supercharged 964 (Ilko) I know of a numerous protomotive turboed 3.2's 964's and 993's. The protomotive cars have all had long track lives with very reliable results and upwards of 80-100 hp gains. It does little for low end torque but improves torque higher up where you need it on the track. These cars have some edge on the track but if you are carrying proper speed they don't gain that much. I found they only help if you get slowed down and need to gain some ground otherwise it is a lot of $$ spent.

As far as a turboed or modified n/a vs buying an actual turbo. My .02 worth. the factory turbo is a blast will hold its value longer but is not as nimble as a n/a car. The big turbo takes longer to spool up and the power is abrupt. You are using old school CIS injection vs motronic. This requires an added skill level to drive a factory turbo car fast but if you can it is a monster you might also want to practice your left foot braking. As far as using the protomotive IC you can use a factory 965 IC and save a bundle. Most people I know who have done the turbo kits started with stage 1 and then upgraded later. In either case a fixed tail is a must if you plan on tracking these cars. They are already IMO at their limits of the pop up tail at most tracks and once you start moving faster the added downforce is needed.

Heat from a small turbo at low boost is not as much of an issue and the small turbo will spool up much faster than the large turbo however they will run out of air at higher RPMS. Plumbing for a turbo is minimal and it will not add much weight to the car.

In the end once you modify or extensively track these cars their value will drop. So you need to decide what is best for you.

I find that my C2 with its simple mods is quite fast once you learn to push it. Spend your $$ on suspension, brakes, exhaust, LWF, intake etc, and if you don't plan on using it much on the street drop weight it is worth so much more than HP.

Don't forget if you do plan on doing more track events safety equipment, seats, etc can get quite pricey.

There is no right answer here. Just opinions. Do what you enjoy best and what is well within your budget.

964speed

This looks like a deal on its surface...

http://cgi.ebay.com/ebaymotors/911-C...=p4506.c0.m245

cobalt

Nice cars, too bad there AWD.

ilko

Unlike the 964, you can easily fix that error on the 993 and later cars

cobalt

It is still expensive to do on the 993. Not as bad as the 964 and no where near as easy and cheap as a 996TT. One day I will own a 993 GT2 evo clone for the track. For now I will have to settle for a lowly 964.

ilko

Viper Bob sells the kits @ around $1000 I believe. Haven't really looked too much into it, but by comparison it's dirt cheap and relatively easy to install.

cobalt

That isn't too bad but IIRC it is a lengthy process. Weight reduction alone is worth it. I was told the 996TT's can be done for around $150 and save around 145 pounds. That is the cheapest performance gain I can think of. Other than body stiffness, instant GT2. To be honest it is hard to resist the temptation of 996TT ownership. Great performance for very little $$ if only it felt more like a 964 while driving.

ilko

And there we have it. Anthony's headed over to the dark side. We need an intervention here...

Must resist

964speed

Water cooled prices are very cheaper by comparison! But I just can't bring myself to do it! Damn! don't go to the light cobalt! RESIST!

wellcraft290

Cobalt go to the water cooled side. Too bad the prices of your 964 turbo are so low now. I will do this for you I will buy the car from you and save you the trouble of listing the car etc. I don't know, figure by the guys here a reg 964 is 15,000 so a turbo lets say 25k. Just let me know when to pick up the car and I will give you the check

Think he will believe me??