Getting 350 HP out of the 3.4L?
#1
Rennlist Member
Thread Starter
Getting 350 HP out of the 3.4L?
I couldn't help but notice the 3.4L in the 981 comes in at 315-325, yet the 991 makes 350, the 997.2 makes 345.
Is there a relatively easy and painless way to draw that 350HP back out? Is it a simple ECU issue, or are the motor's components different between engines in the 981/991/997?
Is there a relatively easy and painless way to draw that 350HP back out? Is it a simple ECU issue, or are the motor's components different between engines in the 981/991/997?
#2
Rennlist Member
I believe I can answer this question thoroughly enough. The difference between the 991 3.4 and the 981 3.4 is minimal/if any hardware (i.e. the intakes are slightly different, air filter assy, etc.), the difference in HP is due to the tune. So yes, there is a really easy way to unlock the HP, get a tune.
#3
Rennlist Member
Tune and headers are proven to get more than 350HP. Tune alone will be close, perhaps 350HP alone. Softronic claims 360HP with tune alone but I've never seen a dyno to back that up.
#7
Instructor
Fabspeed race headers and protune will get you 350, big difference on my BGTS. Plenum / throttle body on 981 is a waste of money according to folks who know a lot more than I do.
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#8
In my case, IPD Plenum & GT3 TB and FVD tune did not get me more than 5 BHP or so, by the butt dyno.
No exhaust mods, yet. Not sure if it will make a difference or not. I bet I am only pulling 260BHP at 5500 feet of elevation.
No exhaust mods, yet. Not sure if it will make a difference or not. I bet I am only pulling 260BHP at 5500 feet of elevation.
#10
I know I have seen folks do dynos comparing the IPD/GT3TB to the OEM 991 plenum/GT3TB for the 3.4 where the OEM showed a better improvement. I tried searching for it now but couldn't find it in the limited search i had time to do, anyone else remember that thread? -Dom
#11
Rennlist Member
Thread Starter
I believe I can answer this question thoroughly enough. The difference between the 991 3.4 and the 981 3.4 is minimal/if any hardware (i.e. the intakes are slightly different, air filter assy, etc.), the difference in HP is due to the tune. So yes, there is a really easy way to unlock the HP, get a tune.
#12
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ECU tune is the equalizer(and then some) between the 981.1 and 991.1 3.4L engine. Check out our gains with tune alone-
http://www.tpcracing.com/tpc-racing-...cu-tuning.html
310 at the wheels, using 15% factor = 365 at the crank. We have tune 50+ 981's. Every customer calls back the next day expressing how impressed they are with the power gain from mid to full throttle. Drives like a completely different engine with the factory electronic governors deleted and then fine tuned.
http://www.tpcracing.com/tpc-racing-...cu-tuning.html
310 at the wheels, using 15% factor = 365 at the crank. We have tune 50+ 981's. Every customer calls back the next day expressing how impressed they are with the power gain from mid to full throttle. Drives like a completely different engine with the factory electronic governors deleted and then fine tuned.
__________________
PCA National Instructor
TPC Racing stats:
2023 Porsche Sprint Challenge 992 Cup Am Champion
2023 Porsche Sprint Challenge GT4 Pro-Am Team Champion
2022 Porsche Sprint Challenge 992 Cup & 991 Cup Champion
2020 IMSA GT3 Cup Challenge 2nd Championship
2018 IMSA GT3 Cup Challenge 2nd Championship
2016 IMSA GT3 Cup Challenge Champion
2013 IMSA GT3 Cup Challenge Champion
2006 Rolex-24 @ Daytona GT Champion
2004 Grand-Am SGS Class Champion
PCA National Instructor
TPC Racing stats:
2023 Porsche Sprint Challenge 992 Cup Am Champion
2023 Porsche Sprint Challenge GT4 Pro-Am Team Champion
2022 Porsche Sprint Challenge 992 Cup & 991 Cup Champion
2020 IMSA GT3 Cup Challenge 2nd Championship
2018 IMSA GT3 Cup Challenge 2nd Championship
2016 IMSA GT3 Cup Challenge Champion
2013 IMSA GT3 Cup Challenge Champion
2006 Rolex-24 @ Daytona GT Champion
2004 Grand-Am SGS Class Champion
#13
The tune should unlock almost all of that power. Porsche likes to play games with HP to denote hierarchy in the model range.
I wouldn’t bother with the IPD/82mm TB unless you REALLY want max power. It just doesn’t realize the gains you’d think it would.
Headers + tune is the way to go... but you’re kind of out of luck after that. If you don’t have PSE, I’d do muffler too.
I wouldn’t bother with the IPD/82mm TB unless you REALLY want max power. It just doesn’t realize the gains you’d think it would.
Headers + tune is the way to go... but you’re kind of out of luck after that. If you don’t have PSE, I’d do muffler too.
#14
Rennlist Member
After talking to Softronic, I was sold on the tune alone. Finished the load tonight, took it for a ride. Butt dyno definitely feels like an improvement. Neck-snap dyno does too.
I'll know more tomorrow - tracking it at my regular place. Will use Harry's and overlay on past session laps - my best lap times are pretty consistent. Should be able to see a bump in the straights if there was a real gain. I've got new tires, so that might make it seem inflated - but definitely a good test!
I'll know more tomorrow - tracking it at my regular place. Will use Harry's and overlay on past session laps - my best lap times are pretty consistent. Should be able to see a bump in the straights if there was a real gain. I've got new tires, so that might make it seem inflated - but definitely a good test!
#15
Rennlist Member
My results after the mod and new tires... 6% better lap time than I've ever had there. Keep in mind it is a very short/technical track. New tires, pads and a tune bought me some kind of improvement. Given I have not been on the track in over 90 days, I'd say the machine had something to do with it.
Value of Results/$$$ = in the eye of the beholder.
Going through lap-by-lap in Harry's, my top speed in the straightaway was no better than some of the speeds before the tune and tires, although again it is a short track.
Value of Results/$$$ = in the eye of the beholder.
Going through lap-by-lap in Harry's, my top speed in the straightaway was no better than some of the speeds before the tune and tires, although again it is a short track.
Last edited by daylorb; 12-02-2017 at 03:23 PM.