30 hp increase....
#1
Race Car
Thread Starter
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is pretty expensive a lots of work...
I had my car dynoed at Sportec before and after to mods to monitor the hp increase.
I got a 15 hp increase with chiptuning combined with sport cat, sport muffler, special air filter.
The second 15 hp increase came with the 3.8L Porsche kit (with camshafts, etc.) and adapting the chip.
Anybody out there with a 3.8L engine and additional mods? If so, what are they and what hp increase resulted?
I had my car dynoed at Sportec before and after to mods to monitor the hp increase.
I got a 15 hp increase with chiptuning combined with sport cat, sport muffler, special air filter.
The second 15 hp increase came with the 3.8L Porsche kit (with camshafts, etc.) and adapting the chip.
Anybody out there with a 3.8L engine and additional mods? If so, what are they and what hp increase resulted?
#4
Race Car
Thread Starter
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Yes, forgot to mention that with the 3.8L kit installation, I also upgraded the car with varioram.
I should also add that while the peak hp difference was only 30 hp finally, the torque curve improved tremendously, and became almost horizontal.
I should also add that while the peak hp difference was only 30 hp finally, the torque curve improved tremendously, and became almost horizontal.
#5
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Can you post your dyno results with your 3.8? What type of reprogramming did you do? Did you not use the RS computer that came with the kit?
I got about 40 hp increase, but I also changed the cats, removed mufflers and changed the air filter at the same time as the upgrade.
I got about 40 hp increase, but I also changed the cats, removed mufflers and changed the air filter at the same time as the upgrade.
#6
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993,
I'd be interested in what you paid to get the initial HP gain (chip tuning, exhaust, etc). Also, what did you pay for a varioram system, and wouldn't that account for 10 hp all by itself?
I'd be interested in what you paid to get the initial HP gain (chip tuning, exhaust, etc). Also, what did you pay for a varioram system, and wouldn't that account for 10 hp all by itself?
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#8
Race Car
Thread Starter
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Sorry, I was in Paris watching Roland Garros Tennis Championships for a couple of days...
A picture of Anna Kournikova (who unfortunately lost)
Bill,
The dyno results are on my web page. The chip programming was done by Sportec in Switzerland.
SharkO1,
The first stage (sport cat, chip tuning, etc) cost be close to 6,000 dollars.
The 3.8L liter conversion, I did together with the Varioram installation. Together close to 10,000 dollars (including reprogramming the chip).
I was surprised I did not end up with more hp increase...
A picture of Anna Kournikova (who unfortunately lost)
Bill,
The dyno results are on my web page. The chip programming was done by Sportec in Switzerland.
SharkO1,
The first stage (sport cat, chip tuning, etc) cost be close to 6,000 dollars.
The 3.8L liter conversion, I did together with the Varioram installation. Together close to 10,000 dollars (including reprogramming the chip).
I was surprised I did not end up with more hp increase...
![](http://boards.rennlist.com/upload/anna.jpg)
#9
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Doesn't she ALWAYS lose
And Quickly
Man, it does get expensive to mod these things
You could add 100 hp to a Corvette with less than $5k <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
The 3.8 liter conversion, I guess that doesn't mean you are using a new engine, but increasing cylinder size, correct?
![Big Grin](https://rennlist.com/forums/images/smilies/biggrin.gif)
![EEK!](https://rennlist.com/forums/images/smilies/eek.gif)
Man, it does get expensive to mod these things
![Frown](https://rennlist.com/forums/images/smilies/frown.gif)
The 3.8 liter conversion, I guess that doesn't mean you are using a new engine, but increasing cylinder size, correct?
#10
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Your torque curve is almost identical as mine, but the horsepower is different. My car peaked at 4,800 rpm's at 277 lbft, and peaked at 320hp at 6,500 rpm's. This is with a stock USA computer no reprogramming at all.
#11
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Shark01,
Yes, just new cylinders, camshaft, etc.
Bill,
What did you do exactly? Did you install the official Porsche 3.8L kit or somebody elses? If somebody elses what did it include in the kit?
I have 280 lb/ft at 4780 rpm, peak hp at 250 lb/ft at 6280 rpm and at 6500 rpm have 230 lb/ft. What lb/ft do you have at these rpm? Thanks...
Yes, just new cylinders, camshaft, etc.
Bill,
What did you do exactly? Did you install the official Porsche 3.8L kit or somebody elses? If somebody elses what did it include in the kit?
I have 280 lb/ft at 4780 rpm, peak hp at 250 lb/ft at 6280 rpm and at 6500 rpm have 230 lb/ft. What lb/ft do you have at these rpm? Thanks...
#12
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Sorry I have been offline for a few day.
The torque number are as follows: 274.8 lbft @ 4800 rpm, 278 lbft @ 5400, 263.1 lbft @ 6300 rpm and 258.1 lbft @ 6500 rpm. The HP number at the same rpms are 253.2 hp, 278 hp, 316.4 hp and 319.4.
The other mods were I bypassed the cats, fabspeed supercup mufflers and a BMC airfilter with a more open airbox cover.
The torque number are as follows: 274.8 lbft @ 4800 rpm, 278 lbft @ 5400, 263.1 lbft @ 6300 rpm and 258.1 lbft @ 6500 rpm. The HP number at the same rpms are 253.2 hp, 278 hp, 316.4 hp and 319.4.
The other mods were I bypassed the cats, fabspeed supercup mufflers and a BMC airfilter with a more open airbox cover.
#14
Race Car
Thread Starter
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Wonder why we have about a 15 hp difference, we seem to have done essentially the same mods...
BTW: I also switched to mechanical valve lifters, which should be preciser at high revs, yet...
BTW: I also switched to mechanical valve lifters, which should be preciser at high revs, yet...
#15
Lifetime Rennlist Member
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[quote]Originally posted by 993RS:
<strong>Wonder why we have about a 15 hp difference, we seem to have done essentially the same mods...
BTW: I also switched to mechanical valve lifters, which should be preciser at high revs, yet...</strong><hr></blockquote>
The difference in HP may or may not be real. Dynos are accurate and repeatable between sites if they are properly calibrated, maintained and if the runs are done in reasonable ambient conditions, with identical oil temps, air flow, etc and results are then corrected to standard temperature and pressure.
Given all the above, it is not uncommon to get variances between dyno sites far more than the 15 HP you are looking at. Even before and after testing is suspect as condtions change. When I did dyno work (as part of my job) we would have to run a baseline, make changes and measure THEN go back to baseline conditions and make sure we could repeat the baseline results. If not, then start all over because the results could not be trusted. Bottom line - If you use a shop that does this stuff right, then you can trust before and after 30 HP difference without going back and re-running the baseline. If the shop is cutting corners, or there are wild weather changes, you can't trust even 30 HP numbers.
This is not a comment about your shop, or any other particular shop, only observations about what can happen.
<strong>Wonder why we have about a 15 hp difference, we seem to have done essentially the same mods...
BTW: I also switched to mechanical valve lifters, which should be preciser at high revs, yet...</strong><hr></blockquote>
The difference in HP may or may not be real. Dynos are accurate and repeatable between sites if they are properly calibrated, maintained and if the runs are done in reasonable ambient conditions, with identical oil temps, air flow, etc and results are then corrected to standard temperature and pressure.
Given all the above, it is not uncommon to get variances between dyno sites far more than the 15 HP you are looking at. Even before and after testing is suspect as condtions change. When I did dyno work (as part of my job) we would have to run a baseline, make changes and measure THEN go back to baseline conditions and make sure we could repeat the baseline results. If not, then start all over because the results could not be trusted. Bottom line - If you use a shop that does this stuff right, then you can trust before and after 30 HP difference without going back and re-running the baseline. If the shop is cutting corners, or there are wild weather changes, you can't trust even 30 HP numbers.
This is not a comment about your shop, or any other particular shop, only observations about what can happen.