Performance improvements

Hi guys, I've got a 911 C4 tip (996) and am thinking of having it tuned and possibly having Miltek exhaust/manifolds to increase power and performance, the firms I've spoken to have said I'll see an incrase of about 30-40 bhp if I get all the work done - it's going to cost about �1800 so not cheap and I wondered if any of you had had this done or similar, I'm trying to understand whether this is money well spent and the gains would be noticeable or not - I had my old VX220 TURBO re-mapped and it made a huge difference all-round. Any advice would be most welome.

What MY car do you have?

If you do some research on the 996TT board, you will find that they have huge success with modifications to increase performance. If you bought one, you would probably be satisfied with the performance for awhile, and then you could start the mods with a much greater return for the dollar spent. If you mod your 996 tip, the resale value might actually decrease and the performance increase would probably be disapointing. Just my 2 pence...

There are a lot of threads around that give you pros and cons on the single tuning alternatives for the n/a 996. General consensus seams to be that the 3.4 engine is better to tune than the 3.6 engine of the post facelift 2002ff models. IMHO there are following things that improve your performance: -exhaust (mufflers, headers, cats) -air intake -ECU (chip) I wouldn't believe the promised HP gains from the single aftermarket suppliers as they can tell you 20HP for the mufflers, 20HP for the headers, 20HP for the intake and 20HP for the ECU, so in total 80HP? BS! With all above measures you may get 20-30HP, so almost the 30-40HP you stated. I doubt that the muffler and header mod alone will bring you 30+HP. However, with the mentioned 1,800KGBP (almost 3.5K$) you should be able to get almost all mods (mufflers, headers, chip and intake) done, so may reach 20-30HP. Keep in mind that performance gains can either be reached with more HP/torque and with lower weight. My next mod are aftermarket mufflers for three things in this order: sound, weight reduction over stock and performance. I further guess that with all the mods money spent on a car with tip and AWD, you'll by most reach the acceleration figure of a stock 6 speed C2; this would be frustrating for me. Just my 2 cents.

hwk72, your reply was well stated. I agree, this has been my experience as well. I do enjoy a slight increase in performance. The improvement in sound is incredible. Enjoy!

Thanks Mfletch! I got one of the 8 GHL exhausts from the special offer here on the board, so I couldn't resist. I know you're probably getting the plenum. I thought it's still too controversial to list it in my post, but if you make positive experience, then share it with us. I'm further impressed with the potential $8K offer (if more than 11 units) for the EVO supercharger for the 3.4 engine. You can never get so much push with single components but almost spend the same amount of money by adding this and that. EVO SuperCharger Group buy

hwk, I would love to get a supercharger...it really makes a huge difference on wifey's Rover. My problem is the stinking California Air Resources Board. I don't want to have to remove it every two years just to pass smog. Evo has been promising for years that CARB certification is pending.....I'm still anxiously waiting. That is an incredible price.

i agree... love that sc..... but would you get the evo or tpc?

My car is faster after I wash it, so i KNOW that any engine mod I end up doing is gonna feel incredible.

I've been checking the TPC route, especially as they are local. TPC charges $11K and installation is not included whereas the comparable EVO price is $10K and with a group buy only $8K (before installation), so $3K difference. I didn't research enough about the differences between their systems but a friend of mine brought up following argument: "The thing that I like about TPC is that they actually race their kits and are obviously successful (came in first last year in that Rolex event). Not sure about EVO. I trust them more on their 911 Turbo applications, since it's on that engine. The non-turbo/gt2 engines are a different breed so EVO upgrades are fine, and I am not sure about how good their stuff are compared to TPC for the n/a engine."

i think if u do a search.. ther's info on both kit... but not enough to make an informed decision....... one of the topic is the noise and when the power kicks in... tpc is noisier and power kicks in sooner but the evo will yield more power and quieter...... of course there's more..... but i don't have either.....

Are you sure about the Rolex series allowing superchargers in this class? IIRC, the TPC car was a Cup car.

hwk72: You're right about the individual versus the combined mods....I ended up going with the whole kit and kaboodle all at once...headers, mufflers, EVOM intake, and GIAC chip...the whole thing together ended up being right under $4K....and I have noticed improvement in performance over what it used to be....but I didn't spend the money to do a before and after dyno. Mfletch and I have been throwing around the idea of supercharging...but I have to tell you that after I've really researched and looked into it I've come to the conclusion that the guys who end up SC'ing their cars eventually sell them off and jump into the TT. I was looking really hard at a SC'd car another Rennlister had for sale....and came close....but (not universally true) I think that if you were to poll the SC guys, you might find that they are satisfied to start with, but then they start looking at the TT's. When you think about it, the TT's are sort of the standard that folks compare performance to. From my perspective, I think I'd rather get into the 3.6L engine than beef up a 3.4L. The prices on the 01/02 TT's are coming down pretty dramatically...and when you start factoring in an additional $10-13K for a supercharger versus just buying a 996TT for the low to mid $50's...the advantages of the newer cars, enhanced technology, and 3.6L engine seems to make sense. I in no way am trying to demean the performance of the SC'd cars....just doing an exercise in economics and personal opinion. Chuck

Kevin, I'm sorry if I may have reproduced wrong info here. I quoted someone and didn't verify the info. Chuck, I think you made the right decision, passing on the SC car. It sounds tempting to add 100+ HP to our car but nothing on the car is really built for this power. The TT has a different suspension, breaks, ... the whole concept it better matched. I always smile when I read the argument that you don't need to upgrade your breaks with a SC as the breaking distance from 62mph to 0 does not change. Bah, the thing is that you're much faster at 62mph with the SC. Another question that I already asked on the EVO SC group buy thread but didn't get an answer to is what weight does the kit add to the already heavy rear end of the car? I fear that you end up with a faster but worse handling car which seams to be dangerous.

There is a guy on the board that has some aftermarket headers for sale for $100. This could be by far and away the cheapest engine mod you could do. And a bonus, he has a dyno sheet to verify the results obtained.

I already told him that he's not a good salesman. He should have sold the headers first and then publish the dyno result or at least transpose digits on the dyno numbers.

i want the headers.....

Yeah...I read those great results...the dyno showed he lost HP and torque....he'd like to off them...would you like them nick? $100 is a great price.

I fear Chuck is right about the TT...it just makes more financial sense...and if you mod it.... I recently saw a low mile TT on e-bay for a buy it now price of $49,000. it had an air bag deployment due to a minor front end collision...no salvage title(unlike mine). It was at a reputable dealership and was seal grey. If I had the money, I WOULD HAVE FORGOTTEN ALL ABOUT THE SC and learned to live with 4wheel drive on my sports car. I bet if you do all the mods to a TT that I have done to mine you could light up all 4 tires.

That guy that put on the Ebay Headers found that a mistake was made during installation. He got that fixed and said he'd repost with new dyno results. But no new dyno results yet.

Maybe the results will be even LESS horsepower. LOL There is a post here someplace that states the tuner RUF has experimented with the N/A 996 and has not been able to improve upon the stock exhaust header. I'm wondering if all these small companies that we have never heard of producing stainless exhaust headers in China and marking them up 10K % claiming outrageous power and torque gains know something RUF doesn't ??? Oh, and I'm sure Porsche just slapped something together header wise that would allow the exhaust to exit the cylinders without regard to maximizing power and torque.

Just as a side note: Europipe http://www.europipe.be/1024.html uses X51 Headers on their 997S exhaust system. they found Porsche headers to be the best with their system after much testing.