31 hp upgrade for 997S !!
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Originally posted by caf
Though I don't post here often, this board is far newer than I am to performance or to Porsche. I wouldn't get so weary of claims from tuners if they didn't so often turn out to be unsubstantiated.
Significant hp increases from an ECU upgrade and "intake" (plus-minus an exhaust) are ethereal.
These are the facts that can be supported:
-It's rather easy to extract additional hp from forced induction cars, at the expense of engine longevity. It's your gamble.
-Useful hp increases from these type of bolt-on mods are very suspect on normally aspirated cars. These claims are usually supported by in-house dyno results and testimonials ("throttle response is much improved!", "the top end FEELS much better", "I'm just SURE I'm getting 20 more hp !"). I'm sure you've heard them all before.
-A dyno run on the same engine on the same day can result in some variation even with no mods whatsoever. It's very tempting for some tuners to take the worst pre-mod dyno and the best post-mod dyno and claim an improvement. Very few of these have scientific validity (i.e. , are consistent, reliable, and reproducible from independent sources). Interestingly, the only independent published tests in recent years showed on average either no improvement with ECU modifications, or a DECREASE in performance. In the case of the C&D tests, the only improvements were from tightening of the shift points on automatic transmission cars, and had nothing to do with the engines themselves.
-Unless a dyno is performed as an engine-out test, or done with a wind-tunnel type set-up as used by manufacturers, they really have little validity, even for before and after comparisons. The reasons for this would require pages of explanation, but Steve Dinan's white paper on dyno testing is a good primer. Although written from a BMW tuning perspective, the same principles of dyno testing are applicable across the board. The article is written in a style that non-technical, non-engineers can follow: http://dinancars.com/whitepapersFile.asp?ID=9
In the end, the age old-wisdom still applies: if you're looking to upgrade performance, look to the suspension and the driver first. Of course, it's your money.
Though I don't post here often, this board is far newer than I am to performance or to Porsche. I wouldn't get so weary of claims from tuners if they didn't so often turn out to be unsubstantiated.
Significant hp increases from an ECU upgrade and "intake" (plus-minus an exhaust) are ethereal.
These are the facts that can be supported:
-It's rather easy to extract additional hp from forced induction cars, at the expense of engine longevity. It's your gamble.
-Useful hp increases from these type of bolt-on mods are very suspect on normally aspirated cars. These claims are usually supported by in-house dyno results and testimonials ("throttle response is much improved!", "the top end FEELS much better", "I'm just SURE I'm getting 20 more hp !"). I'm sure you've heard them all before.
-A dyno run on the same engine on the same day can result in some variation even with no mods whatsoever. It's very tempting for some tuners to take the worst pre-mod dyno and the best post-mod dyno and claim an improvement. Very few of these have scientific validity (i.e. , are consistent, reliable, and reproducible from independent sources). Interestingly, the only independent published tests in recent years showed on average either no improvement with ECU modifications, or a DECREASE in performance. In the case of the C&D tests, the only improvements were from tightening of the shift points on automatic transmission cars, and had nothing to do with the engines themselves.
-Unless a dyno is performed as an engine-out test, or done with a wind-tunnel type set-up as used by manufacturers, they really have little validity, even for before and after comparisons. The reasons for this would require pages of explanation, but Steve Dinan's white paper on dyno testing is a good primer. Although written from a BMW tuning perspective, the same principles of dyno testing are applicable across the board. The article is written in a style that non-technical, non-engineers can follow: http://dinancars.com/whitepapersFile.asp?ID=9
In the end, the age old-wisdom still applies: if you're looking to upgrade performance, look to the suspension and the driver first. Of course, it's your money.
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Originally posted by sticky
Thank you for telling us basic things we already know. The topic here is hp upgrades for the 997s not a debate between horsepower gains of forced induction cars vs. naturally aspirated ones or whether suspension upgrades and driver training are a better way to spend mod money.
Thank you for telling us basic things we already know. The topic here is hp upgrades for the 997s not a debate between horsepower gains of forced induction cars vs. naturally aspirated ones or whether suspension upgrades and driver training are a better way to spend mod money.
If you already "knew" these things, I'm not sure why you would have been asking the questions you were earlier.
Please understand I don't want to be too harsh on the tuners; they also offer many good pieces, suspension mods, etc. which have real world utility.
Anyway, I've said my piece, and for those that believe in the magic of an ECU upgrade and "intake", I hope Santa Claus puts one under your tree.
And maybe for you audiophiles, a set of Kimber interconnects as well (be sure to read the part about "break in"--pretty funny): http://www.stereotimes.com/cables022300.shtm
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CAf.
You are right, just reprogramming the ECU on a N/A car is a waste of time. If you look at the PSI web site you will find no ECU programs on their own. PSI Motorsport have been racing/ tuning Porsche for years. They are also the people behind a lot of top European tuners.
Neil
You are right, just reprogramming the ECU on a N/A car is a waste of time. If you look at the PSI web site you will find no ECU programs on their own. PSI Motorsport have been racing/ tuning Porsche for years. They are also the people behind a lot of top European tuners.
Neil
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Originally posted by Neil
We have just finished our 997S upgrade.400hp.will be available early next month.
We have just finished our 997S upgrade.400hp.will be available early next month.
I would be highly interested as well as most other people if 400HP can be reached reliably. Can you provide us with some more details? Thanks.
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Neil gave me a WHP of about 315 after his mods in another link uin this forum. If what he says is true, he is using a 28% factor to come up with a HP of 403. That's crazy. I hae already seen WHP dyno's of the 997s....let him show us the before and after WHP dyno. You can't just pick numbers out of your head in order to come up with crank HP.
https://www.6speedonline.com/forums/...threadid=20817
https://www.6speedonline.com/forums/...threadid=20817
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The SC does not effect the life of the engine. The engine has no more stress on it than a stock engine does 99% of the time. You can cruise with your SC car at 150 mph and not be using the boost of the SC.
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Originally posted by 1999Porsche911
The SC does not effect the life of the engine.
The SC does not effect the life of the engine.
Also, I agree with caf, more often than not tuner's claimed increases on NA motors are snake oil - not stating anything for this particular case though.
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<<<<I don't think you can really state that until a 997S has been supercharged reliably for a period of time - obviously forced induction is hard on a motor.>>>>
Since you made the above statement, how about some specifics on how the SC, by itself, is hard on the engine. Or are you just repeating popular opinion?
Since you made the above statement, how about some specifics on how the SC, by itself, is hard on the engine. Or are you just repeating popular opinion?
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Originally posted by 1999Porsche911
Since you made the above statement, how about some specifics on how the SC, by itself, is hard on the engine. Or are you just repeating popular opinion?
Since you made the above statement, how about some specifics on how the SC, by itself, is hard on the engine. Or are you just repeating popular opinion?
The 997 S already has a fairly high comprssion ratio (11.8:1), but I suppose the C2 also had a fairly high compression ratio (11.3:1 ), and people seemed to have success SC'ing those engines.
Anyway, I'm not saying you can't SC the 997 S, I'm saying if you think it's EXACTLY as reliable as an untouched engine, you are generally incorrect.
