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Greetings All,

Firstly, I'm very new to 996 ownership but have 2 other Porsche's (964) and (986) in my garage. I'm interested in what others have done to improve their 996 (C4S) cars. This car was purchased to be a 'spirited driver' but not much track use becasue my 964 is built for that purpose and it serves me well. The C4S sits too high for my taste and I would like to lower it. It's way too quit, especially when compared to the 964. It handles well but needs to be stiffened for my taste.

My question to you is regarding modifications of the C4S. What are good, proven modifications to improve the brand;

- Intake upgrade.

- Power Intake Plenum.

- Suspension upgrade (PSS9/10 or H&R) with camber plates & perch plates. Or, just H&R lowering springs.

- Strut Brace.

- Fister sport muffler modification (exhaust too quiet).

How would you guide a new 996 (C4S) owner in their modification journey, or point me in the right place to read and educate myself? Or, is this just a waste of money with no real hp or performance gain?

Thanks for your time,

Sam

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Suspension upgrade is the most worth while with the biggest real impact. Next the muffler mod is you want it to be louder. I have the PSE setup with the switch and quite frankly I really enjoy the ability to go from "loud" to "quiet." However the PSE has gotten ridiculously expensive. I think Fabspeed make a switchable system now at a faction of the Porsche PSE. The others mods are less effective. Maybe the strut brace, but the cars are pretty stiff without it. The intake and plenums are mostly non-productive. Do some searches on the various boards and you will find a lot of threads on these subjects. In general when dyno's the result are mostly nil.

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Suspension upgrade is the most worth while with the biggest real impact. Next the muffler mod is you want it to be louder. I have the PSE setup with the switch and quite frankly I really enjoy the ability to go from "loud" to "quiet." However the PSE has gotten ridiculously expensive. I think Fabspeed make a switchable system now at a faction of the Porsche PSE. The others mods are less effective. Maybe the strut brace, but the cars are pretty stiff without it. The intake and plenums are mostly non-productive. Do some searches on the various boards and you will find a lot of threads on these subjects. In general when dyno's the result are mostly nil.

Dharn55 - Thanks for the reply. Regarding the suspension upgrade. Blisteins PSS9/10 Coilovers or H&R Sport Coilovers or just H&R Springs to lower the car?

- I'll look into what Fabspped has to offer for exhaust upgrades.

- I have read from the manufactuers of the intake and plenums that "THEY SAY" hp increase is gained. I'll do some searches and read about the real world results of these products. They marketed these upgrades as a 15-30hp gain.

Thanks for you time.

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Having been there done that myself, trust me it's a slippery slope trying to make one of these NA cars "faster" or better.

I agree certainly suspension and a.good corner balance goes a long way. So does reducing the weight.

HP gain when you bolt on brand new exhaust, warm air intake, ECU program, maybe worth a few at the dyno. But at the expense of $5k or even more. Not worth it.

About the only thing I think would make a real difference is putting a super charger on it.

For the money, I would rather have a stock 996 or 997 turbo.

Edited by logray
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Having been there done that myself, trust me it's a slippery slope trying to make one of these NA cars "faster" or better.

I agree certainly suspension and a.good corner balance goes a long way. So does reducing the weight.

HP gain when you bolt on brand new exhaust, warm air intake, ECU program, maybe worth a few at the dyno. But at the expense of $5k or even more. Not worth it.

About the only thing I think would make a real difference is putting a super charger on it.

For the money, I would rather have a stock 996 or 997 turbo.

logray - The suspension upgrade was discussed with others and some were warning about the height for street driving, stating I'd have potential clearance issues with city driving. I'm researching the H&R lowering springs as an option, instead of a complete coilover kit. Any thoughts on the H&R lowering springs? Many are saying the cost factor to upgrade the 996 is not worth the hp gains. This car does not have to be the quickest C4S but it still needs to sound like a Porsche, somehting has to be done with the current exhaust notes (or lack thereof.) The Fister exhaust modification seems to be a solution right now for that grunt sound I'm looking for. Any thoughts on the Fister modification?

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I'd recommend the Fister D sport exhaust. For the money, you can't beat it. It sounds great and has no drone. It doesn't add any HP, but the sound alone is worth it.

I have done a few things since we last spoke.

1. Installed a fire extinguisher, utilizing the Rennline fire extinguisher seat bracket.

2. Cleaned my head lights and removed the yellowing of the lens that plagues so many cars. I used a 3M kit with sander, buffer, polisher and sealant wax. A remarkable improvement over original.

3. I'm having the internal muffler components gutted to provide that Porsche 'grunt' I'm looking at. I looked into the Fiester D Sport Exhaust muffler but then decided to modify mine, instead of purchasing one that's been modified. I'll comment on the final outcome when I get my car back.

4. Ordered stainless steel braided brake lines and will install them when I do a brake fluid change out to a high temperature brake fluid.

5. I'm still discussing the suspension upgrade and have not made up my mind which way to go as yet.

6. Not made up my mind on a fixed wing as yet.

As always, thanks for the input and suggestions regarding this C4S.

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Hello.

Yes certainly if you want more sound then mod the heck out of your exhaust. The fister mod is talked about alot to improve sound for less money.

As for suspension. Certainly if you slap on a set of PSS10's you are going to have ground clearance issues over stock. However, we are only talking about a few inches at most. You can raise them out of spec, but perhaps to the detriment of their longevity and ride quality (stiffness), and not a lot of extra clearance.

That being said, I have a set of PSS10's and am extremely cautious around obstacles. I've taken the car onto dirt roads with lots of pot holes and also over tall speed bumps. It takes a much more watchful eye and cautious driving attitude. I would recommend a good quality sump guard. FWIW, the GT2 and GT3 are "street cars" that are normally lowered and I've seen a few on the road - nicer roads albeit - such as Santa Monica PCH in Los Angeles. I'm not sure how the roads are in Jamaicia.

I wouldn't trade the PSS10's for the stock suspension though. They are so much more balanced and "locked" to the road. When the rear end gets loose it is much more predictable. They are also adjustable, on the highest setting the car is on rails, and on the lowest setting it becomes more tolerable to daily driving. Although still much stiffer than stock.

Hope this helps.

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Sam

Have you thought about the factory X73 sport suspension? I have the equivalent on my C4 and like it quite a bit. The positive it that it is factory, the drawback is that it is not adjustable.

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Had my car inspected by an Independent Porsche Shop and some minor issues were noted and fixed accordingly;

1. 1 horn is non-operational - Replaced both.

2. Left front axle boot is torn - Clean inspect CV joints, grease CV joints and install new axle boots on drive shaft.

3. Changed brake/clutch fluid and installed new S/S braided brake lines.

4. Water pump leaking - Installed new water pump, Poly Rib Belt, thermostat and antifreeze coolant.

5. Fuel door hinge is broken - Installed new hinge.

This weekend I'll install the Fire Extinguisher Mount and Fire Extinguisher in front of the passenger seat and then replace the 2 rear tires. This completes getting the car back up to excellent condition. I have no other known issues to deal with right now, so it's just left to drive and enjoy this C4S now. (The 964 is going to have a Momo Wheel installed this weekend and new front brake pads and sensors. Also, need to adjust the H&R Suspension to a firmer setting.)

Sam

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Hello.

Yes certainly if you want more sound then mod the heck out of your exhaust. The fister mod is talked about alot to improve sound for less money.

As for suspension. Certainly if you slap on a set of PSS10's you are going to have ground clearance issues over stock. However, we are only talking about a few inches at most. You can raise them out of spec, but perhaps to the detriment of their longevity and ride quality (stiffness), and not a lot of extra clearance.

That being said, I have a set of PSS10's and am extremely cautious around obstacles. I've taken the car onto dirt roads with lots of pot holes and also over tall speed bumps. It takes a much more watchful eye and cautious driving attitude. I would recommend a good quality sump guard. FWIW, the GT2 and GT3 are "street cars" that are normally lowered and I've seen a few on the road - nicer roads albeit - such as Santa Monica PCH in Los Angeles. I'm not sure how the roads are in Jamaicia.

I wouldn't trade the PSS10's for the stock suspension though. They are so much more balanced and "locked" to the road. When the rear end gets loose it is much more predictable. They are also adjustable, on the highest setting the car is on rails, and on the lowest setting it becomes more tolerable to daily driving. Although still much stiffer than stock.

Hope this helps.

Thanks always for your time to respond. I drove the wife in the C4S this past weekend and she thought the car was stiff enough. She also commented that this car should not feel like the 964 which has H&R Sport Coilover Suspensions (Red) and it's bone jarring hard for track purposes. She hates the 964 and in the 3 years I've owned it, she has never driven it. I promised her I would'nt do that to the C4S. The process of suspension upgrade will wait awhile as I drive the car and enjoy it, as it is. I would use the Bilstein's PSS 9/10's when the upgrade is justified. It was mentioned that the car would be extremly low with the PSS 9/10 installed but when I compared the 964 ride height with the H&R Coilovers installed, to the C4S's, there's allot of room to work with, so that's no longer a concern.

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