Anyone with a 991 3.4L want to upgrade to a Power Kit GTS engine?
09-30-2015, 12:52 PM
#31
We have a Stage 1 kit for the GT4 that takes power from 385HP to 420HP and it would be the same mods but you have to be comfortable modifying a stock car in the form of stainless steel longtube headers with 200 cell cats, high flow air filters, upgraded ECU flash and a lighter flywheel for added power and torque.
Assuming only mod is Long Tube Headers w/ 200 cel Cats (on a 991s).
Also, is the LWF just for manuals?
06-25-2017, 12:17 AM
#32
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I got an inquiry from someone on the west coast with a 991 3.4L with a bunch of mods. The car had become a bit of a project car but the owner wanted more power. We created a quote for $28K to take the 3.4L 991 from 350hp to 430hp. This car had all stock parts...some aftermarket mods would produce another 15hp or so.
If you have a 3.4L 991, have some money invested in the car and only want more power, we are going to open this up to Rennlist members that would be interested.
It would be a brand new 991 Power Kit GTS engine with a 2 year warranty.
The rest of the car's warranty is still in good standing. If you love the 7-spd in your car but need more power to hang with the GT3 crowd, maybe this is of interest to you.
If you have a 3.4L 991, have some money invested in the car and only want more power, we are going to open this up to Rennlist members that would be interested.
It would be a brand new 991 Power Kit GTS engine with a 2 year warranty.
The rest of the car's warranty is still in good standing. If you love the 7-spd in your car but need more power to hang with the GT3 crowd, maybe this is of interest to you.
08-18-2017, 03:34 PM
#33
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That's the thing...that motor is already rather robust when you consider that you're making the same power and torque essentially as the previous 3.6L, but with less displacement. It's all made possible via the new tuning, revised cam shafts and their moving to a Manifold Absolute Pressure sensor for the engine management vs. the prior generation stuff that used a MAF sensor.
You would need some bolt-ons in the form of headers, filters, mufflers to juice it another 20 - 25hp. The addition of an ECU flash and lightweight flywheel would guarantee that you netted an additional 15 - 20. So, i think it's conceivable with all of those things to reach 375hp crank with the car, especially with full exhaust, flywheel and ECU. It already has the single most effective upgrade, the larger 82mm throttle body.
You would need some bolt-ons in the form of headers, filters, mufflers to juice it another 20 - 25hp. The addition of an ECU flash and lightweight flywheel would guarantee that you netted an additional 15 - 20. So, i think it's conceivable with all of those things to reach 375hp crank with the car, especially with full exhaust, flywheel and ECU. It already has the single most effective upgrade, the larger 82mm throttle body.
I have a DD '13 3.4L 911 Cab w/ 7 sp manual..
The car runs great 2nd through 7th, but it seems too slow out of 1st gear. I do have Sports Mono and Sports Plus, but i am not interesting in racing, only getting off a stop light quicker. Checking in to see if a "Chip" or a 'Sensor' has been created in last 2 years to achieve this objective, without going through a bolt-on parade of gear... Hoping for a quick/'cheap'/easy solution to allow me to run up to Orlando and complete.
Thanks, MikeFtMyers
10-13-2017, 10:03 AM
#35
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Ladies & Gents,
I apologize for the lack of response to these questions. Somehow i turned off the notifications for the thread and i just figured that no one cared anymore. We are however about to take receipt of a 991.1 3.4L Carrera from NorCal that has a Power Kit engine inbound from Germany and i am going to document everything here. If i reply to the comments below and i already have or they have already been answered, i apologize. I scanned through them though and my replies are below.
We do not need to entertain this anymore because the cost of that project far exceeded the value of it. HOWEVER, what we have been doing on the Caymans & Boxsters is to use the X51 / 991 GTS bits mated to the GT4/Boxster Spyder engine but with the addition of a crank, rods and pistons to increase displacement to 4.0L, all of which is reversible with no manipulation to the engine case. These motors are producing near 485HP at the crank with all bolt-ons associated and the bottom end torque is equal to or greater than that of the GT3RS. this is however in conjunction with a full aftermarket exhaust vs. the GT3RS having a stock exhaust. I believe it was however tested with some aftermarket GT3RS headers after the fact but it was found that peak power was essentially the same before and after on the GT3RS.
The 3.4L and the 3.8L share the same stroke and crank shaft but the 3.8L has a larger bore. They both rev to 7800 RPM and they both can rev higher. To get a 3.4L to 390HP would require a lot of modification in the form of race gas, full race exhaust, pulleys, lightweight clutch and 8200 RPM and even then i fear you would stall out around 370ish HP. I think that it's probably best said that the 3.4L's making 350 HP is pretty impressive; i think that the 3.8L has more potential than even what is in the S.
How is the car running?
The number to execute has stayed somewhat the same because of the lack of substantial movement of motor pricing. In order to be able to buy the motor for $21K we need to return the existing 3.4L engine & right now the core value of the 3.4L 991 engine is $10.5K and the dealer's core price requirement is $11.4K. So to be able to buy the Power Kit motor for $21K, i need to send back the 3.4L to Porsche and that's a good deal because on the open market the motor trades for about $11K used.
I get good rates from Angel's in Northern California. I realize this was a long time ago that you replied but i am just providing the information. As mentioned above, the 3.4L can be juiced up to about 370HP with a tune, headers and some filters. a lighter weight flywheel will make all of this feel even better since the motors love when you lighten up the mass on the drivetrain.
Please see above. Those numbers do not include any sort of aftermarket exhaust options for the car or intake upgrades other than what comes with it. Since the 991 Power Kit motor has what we think is probably the most efficient, most well designed intake manifold in Porsche street car history, all we suggest for intake upgrades for this car are improved filters. The brushed aluminum intake manifold on the X51 is worth its weight in gold!
If you are horsepower hungry and you want to make 450HP then we recommend it. I tell people not to expect a single additional lb/ft of torque from the X51 upgrade as the larger intake produces substantial horsepower above 5000 RPM. If you want a motor that pulls all the way to the redline like a Cup car and you're tired of guys with GT3s harassing you, then i would get it! It's the engine configuration i went with on my GT4 and had i not been forced to sell the GT4, i would have upgraded it to 4.0L spec but i am now selling it to be able to restructure the business. (it's in the classifieds section by the way 
If you have 200 cell cats you don't need the ECU flash because i am putting the factory X51/GTS flash in the car. This is already a rather aggressive tune for a stock car BUT if you're looking to free up some power in the mid range, it's substantial. I will admit that i was pretty skeptical about tunes and their ability to produce power and torque and it's crazy when you see that while you might pick up 10hp at the wheels on a peak basis, i have seen the tune produce as much as 30 rwhp and 30 lb/ft at the tires in various parts of the rev range.
I have not seen one in a while. I know that they were out there on the 997.1 cars but i don't know what sort of success they had with them. Since we live in a part of the world where it's hot and our customers go on track through the heat of the summer, I really only recommend the NA route for them. For street driving i am sure the supercharger or turbo will be fine; also, let me be the first person to acknowledge that you can pick up massive gains for less money with forced induction but i can't in good conscience tell you that you can beat your car up on track at Sebring in July if you have an aftermarket solution like that.
I think that you and I have spoken somewhat already. Some of it is tuning and the rest of it can probably be improved with a lightweight clutch that can still maintain that street car drivability.
Please see above.
I apologize for the lack of response to these questions. Somehow i turned off the notifications for the thread and i just figured that no one cared anymore. We are however about to take receipt of a 991.1 3.4L Carrera from NorCal that has a Power Kit engine inbound from Germany and i am going to document everything here. If i reply to the comments below and i already have or they have already been answered, i apologize. I scanned through them though and my replies are below.
We do not need to entertain this anymore because the cost of that project far exceeded the value of it. HOWEVER, what we have been doing on the Caymans & Boxsters is to use the X51 / 991 GTS bits mated to the GT4/Boxster Spyder engine but with the addition of a crank, rods and pistons to increase displacement to 4.0L, all of which is reversible with no manipulation to the engine case. These motors are producing near 485HP at the crank with all bolt-ons associated and the bottom end torque is equal to or greater than that of the GT3RS. this is however in conjunction with a full aftermarket exhaust vs. the GT3RS having a stock exhaust. I believe it was however tested with some aftermarket GT3RS headers after the fact but it was found that peak power was essentially the same before and after on the GT3RS.
John (BGB), is it possible to get rid of the "de-tuning" of the base 3.4 engine in the 991? I really wanted the 3.4 over the 3.8 since it revved so much more freely when I tested both. I just don't like the idea that the 3.4 was a bit de-tuned. In theory, the car can produce about 390HP? Given the HP/L ratio of the S engine?
Is there anything one can do?
Just took delivery on my ordered 991 base for a DD car. A great car. So far not much fun since I have to take it slow.
Is there anything one can do?
Just took delivery on my ordered 991 base for a DD car. A great car. So far not much fun since I have to take it slow.
I have driven my '12 Carrera almost 47K miles in three years so I feel pretty obligated to keep it. A "sleeper" engine intrigues me.
For the $25Kish price you quote for the new Powerkit engine, do I get to keep my 3.4L too? Selling that would offset a chunk of the upgrade.
For the $25Kish price you quote for the new Powerkit engine, do I get to keep my 3.4L too? Selling that would offset a chunk of the upgrade.
I think the 3.4L engine is very nice. The tachometer needle just jumps on a small blip, the noise, high pitched and more F1-esque than the 3.8.
Would love to wring out every last drop of reliable power on the 3.4. I will be giving you a call John. I am getting more and more excited.
I am in Los Angeles and you are in Florida. Do you have a transporter you usually work with?
Would love to wring out every last drop of reliable power on the 3.4. I will be giving you a call John. I am getting more and more excited.
I am in Los Angeles and you are in Florida. Do you have a transporter you usually work with?
Hi BGB, i have similar question 997s07 had 2 years ago and hoping for a new answer : )
I have a DD '13 3.4L 911 Cab w/ 7 sp manual..
The car runs great 2nd through 7th, but it seems too slow out of 1st gear. I do have Sports Mono and Sports Plus, but i am not interesting in racing, only getting off a stop light quicker. Checking in to see if a "Chip" or a 'Sensor' has been created in last 2 years to achieve this objective, without going through a bolt-on parade of gear... Hoping for a quick/'cheap'/easy solution to allow me to run up to Orlando and complete.
Thanks, MikeFtMyers
I have a DD '13 3.4L 911 Cab w/ 7 sp manual..
The car runs great 2nd through 7th, but it seems too slow out of 1st gear. I do have Sports Mono and Sports Plus, but i am not interesting in racing, only getting off a stop light quicker. Checking in to see if a "Chip" or a 'Sensor' has been created in last 2 years to achieve this objective, without going through a bolt-on parade of gear... Hoping for a quick/'cheap'/easy solution to allow me to run up to Orlando and complete.
Thanks, MikeFtMyers
Please see above.
10-13-2017, 11:35 AM
#36
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We do not need to entertain this anymore because the cost of that project far exceeded the value of it. HOWEVER, what we have been doing on the Caymans & Boxsters is to use the X51 / 991 GTS bits mated to the GT4/Boxster Spyder engine but with the addition of a crank, rods and pistons to increase displacement to 4.0L, all of which is reversible with no manipulation to the engine case. These motors are producing near 485HP at the crank with all bolt-ons associated and the bottom end torque is equal to or greater than that of the GT3RS. this is however in conjunction with a full aftermarket exhaust vs. the GT3RS having a stock exhaust. I believe it was however tested with some aftermarket GT3RS headers after the fact but it was found that peak power was essentially the same before and after on the GT3RS.
If I have a stock 3.8, how much would it cost to do the 4.0/485hp modifications?
10-13-2017, 04:07 PM
#37
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10-19-2017, 09:28 AM
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thank you.
10-19-2017, 09:36 AM
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10-19-2017, 10:43 AM
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10-19-2017, 11:21 AM
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10-19-2017, 11:54 AM
#43
if any of you get the 4.0 485hp upgrade I'm begging you to post a detailed review. I'm trying to get a manual gt3 as well but glad to here there are different ways to skin the cat.
10-25-2017, 10:43 AM
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This 991 3.4L arrived yesterday from NorCal and the boys should have the motor out by lunch; the brand new 991 GTS Power Kit motor will be ready for install once the existing 3.4L is out. Stay tuned!
Last edited by BGB Motorsports; 10-25-2017 at 11:40 AM.