good2go

///M3THOD

You would think they would a variant of the radiator assembly that would work with ACC.


A radiator is for engine cooling. The engine temperature is regulated by coolant pumped through it. The radiator is a heat exchanger. It uses engine coolant pumped through the metal fin assembly to exchange heat with the air passing though the radiator. The cooled fluid then is pumped through the engine removing and regulating more heat. Its a cyclical system.

An intercooler operates on a similar principle, but it is used to cool the intake air temperatures. As the turbo compresses air, it heats up. The IC passes hot compressed air from the turbo through a fin matrix to exchange heat with the air passing through it. Its used to cool the intake charge before combustion. Cooler air intake temperatures, denser charge, equals more power. (There are coolant based intercooler systems, but thats not applicable on our cars.)

Theres obviously a lot of other considerations and implications, but thats the simple definition and difference.

arter

radiator cools the water that cools the engine.
intercooler cools the air that passed through the turbo ( and got heated up) and then goes into the engine to be combined with gas and burned.
If this air is not cooled, it is not as dense and less of it can be forced into the engine ( reducing power).

good2go

tango131

blurum

pfbz

Hey guys....

I'm really considering a manual, base 991.2. Ideally/eventually I'd like to upgrade it to the X51 (GTS) turbos and a cobb tune, but wondering how it might do short term with the base turbos, sport exhaust, and Cobb tune.

I currently have a 996 Turbo, stock but for a stage 1 Cobb tune, and just don't want a replacement to feel painfully slow.

Cobb says the 991.2 stage 1 tune on a non-S base (49mm turbos) is about 435 HP to the wheels and 460 TQ... Never had my 996 on a dyno, but that seems like it is probably not too far off my to-the-wheels horsepower.

I know i'd be thrilled once fully upgraded, but does anyone have some seat time on a lowly base with the Cobb stage 1 tune?

///M3THOD

Your COBB tuned base is likely faster than a stock GTS.

You cannot use the X51 power kit on the base and keep the factory warranty . You can use aftermarket options which are currently being released. They will bolt right on and then you can tune for them with the Accessport.

Your tuned COBB Base 991.2 is at least as fast as your 996 turbo. Don't forget you can add cat bypass pipes or sport cats, upgraded IC's, turbo's etc.

Honestly, IMO, the base C4 is the way to go if your planning on doing bolt ons and tuning. You get the wide body, awd, and then you drop turbos, IC's, all additional bolt ons and your at 600awhp for around 10-12k.

tango131

///M3THOD

You're correct. I should clarify, what I meant is your cannot have Porsche refresh the ECU based on your VIN and retain the factory warranty. Porsche will not allow base model carreras to use the x51 power kit. You're essentially paying the extra money for the warranty that you cannot use.

You could bolt them onto the Base car, but at that point your just buying a turbo upgrade. Why not buy an aftermarket option like the TiAL turbo system thats just coming to market. Far more potential for a lower price.

Valvefloat991

The GTS turbos may bolt up to the base car, but they also have larger diameter impellors and turbines than the base and the S models. Here's how the impellor (intake)/turbine (exhaust) dimensions stack up:

Base 49/45mm
S 51/45 mm
GTS 55/48mm

pfbz

yup, aware of this limitation. I'm paying for a "software license" that I will not be able to use, and would be 100% dependent on Cobb (or other) tunes to make it run right.


With Suncoast pricing of only $5,800 for the X51 kit, seems like throwing away the license (and any associated warranty retention) is kind of non issues. For me, the big advantage is that all the development work and maps for other GTS/X51 cars would be plug-and-play for my car without having to spend lots of dyno time dialing it in... This thread being a *perfect* example!

I like that idea as well and should look into it further, but I'm guessing there is no way I'm getting a pair of bolt-on TiAL's for less than $5,800, even without the additional tuning expenses?

Benedict14

AlexZTuned

Not sure what TiAL's will cost, but there's also mcchip-DKR and TPC Racing with turbocharger upgrades available. I'm sure there will be even more options as the aftermarket ramps up. The X51 kit with bolt-ons and a Cobb tune on a base would probably be the best bang for your buck. Although with larger aftermarket turbos, I'd go with a C4 instead of a C2 to put the power down.

Also, Cobb tuned one of the TiAL turbo 991.2's so maybe there will be a canned tune available for those turbos at some point?

4 Point 0

Oh Hey Sticky. What's up? What is the current US1/4 mile trap record, and for what? 991.2?