Basic 3.2 Performace Tips
 

I am considering injecting HP into my stock 87 Carrera Cab/G50 3.2 moving up to the SW Chip, K&N, exhaust, muffler and cam for starters. Which camshafts are the HP upgrade for the 3.2L, the 964 or 993? What mods need to happen once cams are updated? I've read somewhere the drive on the cam is somewhat different from the stock cam, comments? Which exhaust w/flipped flanges, 964 or 993? Finally, if you have an SW chip, are you able to send it back to SW for reprogramming if your config changes? Thanks for your tech tips!!

For starters, you can forget about installing a K&N...All they do is introduce more dirt. Do a search

964 cams have the ps drive on the end of the camshaft. You can either cut it off or get the plate to accept it. I still don't know about all the bad rap K&N gets. Other than people not knowing how to wash and oil them.

Opinions vary. Had one on mine for 45K miles, and the AFM and TB are as clean as a whistle.

I still run a K&N on my 87 Targa but I do have proof it destroyed the air sensor on my wifes 2002 Boxster. That being said the answer to your SW chip is yes, I had sent my back twice to be re-calibrated when I relized the po had put in up grades. Enjoy.

ok, here is what I have done with my opinion only on how they affected performance.

K&N filter. no difference compared to stock.

Cutting holes in the air filter cover. no difference but sounds faster... lol

putting all new sensors in for flywheel and cylinder head temp. huge difference in driveability which is just as important as power if you ask me.

new fuel relay does wonders as well. make sure your engine runs right before you try to make it faster!

Catalytic converter bypass on stock heat exchangers. sounds better and felt freer revving

SW chip for stock exhaust. HUGE do it now!

flow test and rebuild injectors. another big step in the right direction. goes back to getting everything in good condition before trying to make it faster.

rebuild of tired engine with worn valve guides and piston rings. feels like a new engine!

SSI's and M&K 2 in 1 out muffler and SW 93 octane chip to match. holy crap!

cams will move the peak torque and power around unless you start to do serious interior engine mods to benefit them. unless I am mistaken.

next for me might be to bore out the intake not sure if it is necessary though.

Right, it's possible for them to oil the wire-type air sensor. The subject Motronic cars have a different AFM.

It would be interesting to see some dyno results for the various changes.

Steve Wong has a bunch of dyno results for 3.2l engines in different states of modification

I was going to change to SSI and M&K exhaust with a extrude hone intake and SW chip but....will this need to be combined with a cam change (964) to really see improvements?

For air filter infor look here
Air Filter Filtration Test

This site should be required reading before you buy.

Most times, suspension upgrades, brakes, and lightening the car are the most significant mods that result in better lap times. Unless of course, you are only looking to go fast in a straight line. Either way, bring your check book.

I have reduced weight by 200 lbs and improved the torsion bar rate and the shocks. I would like to upgrade the sway bars and put in some chassis reinforcement. The car should be faster but I also wanted to get some basic power improvements also.

So smog is not an issue in Cali?

I have owned a 3.2 Carrera for something like 3 years this month (hard to believe I've had it that long). I've been reading everything "Carrera" that pops up here for that length of time.

The consensus is that the exhaust is definitely constipated. Crawl under there and tell me it doesn't look constipated. I'd put any money in the tune up mentioned, a much freer exhaust (flipped 993 exchangers have looked the best to me) and a Wong chip to match.

Next would be Euro pistons and then maybe a bored out throttle body. I guess the 964 cams are a given if the heads come off and the pistons are replaced. Some mild porting of the heads would be nice, but I don't think you'd gain all that much keeping the Motronic fuel injection.

Every little bit helps, but people report the biggest gain by losing the stock cross over exhaust.

lose weight!

You don't have to literally get cams out of a 964. You can get your cams ground to this profile or send them for an exchange.

My recommendation for more power is a cat bypass if you live in a place where smog isn't an issue, 964 cams and a SW chip custom programmed for this set up. If you do this work yourself, it is a cost effective hp gain. If yo upay someone, the cams may have to wait until you have the engine out / heads off anyway.

K&N filters IMHO are fine in terms of filtration. I have had them and the oil analysis would always come back clean on air filtration. They are not really adding a lot of power though, if any - the Porsche air filters have a huge area and really don't restrict flow.

George

Most cost effective HP gain IMHO, Cat bypass, free flow muffler (Dynomax/Flowmaster/Magnaflo/Bursch) and a custom mapped chip from Steve Wong. (911chips.com) You might see 30hp gains right there, plus better low end driveability and big MPG improvement!... Of course you will see even more gains with a 964 cam, and extrude hone, but the price tag really starts climbing with the last 2! Headers help as well, but you lose the heater.

You can use B&B headers and still have heat.

Agreed the most important thing is to first ensure your engine is in proper operating condition to begin with.

>Fresh fuel and air filters. I'd vote for the paper filter. Cheap and flows plenty
>Plugs and O2 sensor should be fairly fresh. Don't get crazy with plug choices. Basic Bosch or NGK coppers are perfectly fine.
>Agreed the head temp sensor should be checked. One wire sensor is known to cause driveability problems.
>Reference sensors are not a driveability problem. They're an on-off sort of effect.
>Check that your throttle linkage is properly adjusted. You'd be surprised how many people find they're not getting full throttle. This is important because the full throttle switch can't be activated if you're not getting full throttle!
>Run some good cleaner thru the fuel system. You'd be surprised by how much carbon buildup can be on some engine's valves- especially exhaust. My favorite is Berryman B12 Chemtool. Cleaned up my valves in one tankful.
>Agreed the injectors are not always flowing at their best and even a fuel treatment doesn't fully fix that.

That's just maintenance-type stuff. Performance?

>Exhaust i'd recommend a good muffler and dump the cat. The factory exhaust system isn't optimum, but it does OK.
>Cams i'd recommend 964 (like George said, no need to buy actual 964, just get yours reground to 964 profile) and that's all unless you're willing to change the pistons. The factory "smog" smushed top pistons don't let more aggressive cams do their thing.
>For a G50, i'd recommend getting a lighter clutch. The factory clutch is a boat anchor. 3.2 throttle response is fairly lethargic, so the lighter clutch helps. Those who have a chip upgrade will tell you that it makes the response lightning quick, but it's still rather slow compared to a more effective injection system like individual throttle bodies or carbs.
>Chip is a wise move. Steve Wong's 911 chips are great and his support is excellent as well.

Make sure you look at some reliability upgrades too.

>How old are the chain tensioners?
>How are the valve guides?
>Consider having your air flow meter refurbished/checked for good sweep on the contact surface

Lastly, yep, lightening is the cheapest HP you can get. All depends on how much you're willing to sacrifice. Do a search for ShakinJoe "438 lbs gone" and you'll see how far he took it. His is an extreme case of street-to-track transformation, so i'm not suggesting that's what you have to do. Point being is Joe did a great job documenting how much weight you lose from each deletion, and in some cases the replacement weight with new part. So you can pick and choose what you want to do, based on the net gains. The general rule of thumb is 10 lbs = 1 hp. Lose 100 and you gain around 10. Obviously you're not putting hp into the engine, just relieving the load on it. Still, the effects of weight loss are real w/out question.

Or those from Rarelyl8. They have heat exchangers that can be added. I haven't seen anyone that has used them, but there must be someone around here...