Fined

Getting a dyno from a built 4.0 liter 997 engine is ever elusive. Somehow there are consistently posts about these engines being built to 4 liters or more and then when it comes to the numbers they put down.... *crickets*****

bronz

I know there are more m97 4.0s out there, but i know what youre saying, they show up and disappear immediately. I couldnt find any numbers on 9a1 4.0 anywhere in the world. I found one short clip of FVD built 4.0 9a1 on youtube. You can count on me to see some numbers and plenty of videos once its done

DrJordan1911

I'm 4.0, I just haven't dyno'd mine. Been running well...so much so that I briefly considered trading my Cayenne S and 997 in on a 991.2 S...but when I drove the 997....I scratched the whole deal. I love it. I need new ignition coils but I'll book some dyno time at some point.

rodH

Im getting an LN solution installed in a couple weeks and since I plan on keeping it a long time am a little worried about bore scoring and then having to sleeve it, which then leads to the logical decision to increase the displacement. Trying to do research on it is a little hard, 4.0? 4.1? 4.2?, even seen mention of 4.4L. Trying to figure out Dyno figures and what it is worth (if someone is spending $20-30k, it better be worth it). but NOTHING!!! I can't find anything out there. Logically, i'd assume that once the engine is broken in, any shop that you spend that kind of money on would be more than willing to have you come back and dyno the car, if nothing else to prove what their work did. What is going on here? This thread just dropped like a rock. Perhaps something went wrong and no one wants to look bad and they are working on the fix?

Petza914

Yea, it's weird. The last update from the owner or TPC on the build was in April. Doesn't seem good.

Hammerman501

Sorry to leave everyone hanging... I didn't receive a notification about any of these posts and wasn't aware of their additions. I picked up the car a couple months ago and have been driving her during that time. The plan is to put 1000 miles on the engine, analyze the oil, change it, and then put her on the dyno. We don't yet have numbers to share with you, but I can tell you that the increase in torque is significant.Throttle response was also increased but I'm not sure is that was the engine rebuild or the ECU tuning.The new exhaust system has a pretty bad drone between 2000 and 3000 rpm and TPC is working with me to design a Helmholtz resonator for the exhausts address that problem. Gas milage has not taken a significant hit but I don't have numbers for that either.I used to get about 400 miles per tank and it is still in that range. So, no numbers yet but they will come. Overall TPC did a fantastic job on this but I can tell you they probably would not want to do it again. We discovered that the X-51 system was never really intended to go on the 997.1. The parts all fit but the 996-based control systems could not accommodate both exhaust bypass valve control and the sport chrono system. Some real creativity was required there and... bye bye sport chrono. TPC did a great job addressing and resolving all these problems. I have no regrets but stepping back I wonder if this was the best use of my money. With all the mods to the car, including front and rear GT 3 bumpers, bigger front brake discs with six pistons, new wheels, front radiator, GT 3 shifter and a lot of GT 3 plastic parts to improve airflow around the front radiator, the engine rebuild, the new exhaust system, the TPC active suspension system (which I love)... it all adds up to a little more than $70,000. If I'd known that is where I was going to end up I probably would have bought a GT 3. But aside from the wheels and the muffler bypass, I have a a unique 997 that is all Porsche and accelerates like a rocket. I love driving the car, I'm happy with the work, have a bit of buyer's regret, and would not recommend this kind of project to others with a 997.1. Numbers after the oil change (currently at about 700 miles).

Fined

Well.. either way, it sounds like an awesome build. And quite possibly something to hang on to forever. If you had the car another 25 years then the money spent becomes less significant over time I'd guess.

Hammerman501

Hahaha... that’s the way I am looking at it. I’ve had the car over 10 years so it is less than $7k per year already! In another ten years it will be $3500!

Petza914

I'm glad the build was a success and am looking forward to the update once break in is done and you can really get on it.

Now I would strongly suggest you put an agreed value policy on it with someone, as you need about a $100k policy to cover the $40k car you started with and the $70k you invested. If the car gets into an accident and you have regular insurance, it's going to be very hard to get an insurance company to pay you more than the $40k they show as the NADA value.

Personally, I have an Agreed Value policy with Grundy for all my cars.

rodH

Thanks for the update. Seeing as many of the parts or the build is either fully custom parts or GT3 parts and working with 2 different companies and shipping an engine back and forth, I knew that this was going to be a very expensive proposal. You wanted the ultimate non GT3 with legit GT3 like performance, it’s going to cost. I currently see 2 997.1 GT3 motors on the market for around $25k with low miles. Also sounds like the high performance rebuilds from Jake and others usually run $20-27k. Sounds like you probably could have gotten 95% of the performance and looks for around 40% of the cost. It’s just another example of the law of diminishing returns. Looking back, you’d have to sacrifice a lot of the uniqueness of the car, though and once you go down the path of how you want it exactly, it’s hard to go back (for me, to motor and the body work, sans center exhaust rear bumper with full custom exhaust would have probably been where I stopped, unless you could have gotten the center bumper and a much cheaper exhaust to bolt on). All the other stuff is really nice, but very pricey. But that’s just me. I’m sure in a couple years you won’t regret it’s uniqueness and the effort put into it.

qikqbn

Thanks for taking us on this journey with you. Also thanks for your honesty and keeping us posted. Still looking forward to seeing the dyno graph. My signature line says "there is a fine line between hobby and mental illness", because I know myself and I know I like to tinker and modify. I have owned my 997 almost 10 years now and have about 10k worth of mods on it. (upgraded bumper conversions, sideskirts, springs, sway bar, wheels, ducktail, intake/exhaust mods) It adds up really fast and I absolutely love how my car looks and feels. It is my unique ride and dialed in just for me. I tell myself it is one of my forever cars. My oldest Porsche I still have and have owned 20 years. So seeing myself own the 997 for 10 more years and still look pristine is what I have in mind. Who knows, we will see, but for now I have no plans to sell.

I , like so many here, was very curious to see how your project turned out. A 4.0 liter upgrade is a real possibility for me and always in the back of my mind, but only in the case of a failure or signs of a failure coming become noticeable. You took it many levels higher than I would with all the extra X51 add ons, so I was excited for you and eager to hear how it turned out. I am often at a crossroads with my inner self. There is a part of me that is very happy with my current setup. Sure, more power would be more fun, but the car is already amazing. Then there is the part of me that wonders what I should do in the future if, God forbid, an engine failure occurs. I often wonder to myself if the 4.0 upgrade is the "best use of my money". If I want to stay naturally aspirated and keep my car, then the 4.0 upgrade for $27k from Jake Raby is the way to go. But I would not necessarily do it because I want "GT3" power, but because I want the best version of this motor I could have for my car over the long term. The extra power and torque would be icing on the cake and cherry on top, but not the main reason to do the upgrade. What I appreciate about your honest comment is that it has validated my own feelings. That If my itch for more power ever gets too strong then I think it is time to bite the bullet, sell my car, and buy a Turbo or a real GT3 before ever going down that rabbit hole of modifying a car to be a GT3 tribute.. Just remember, no matter what version of 911 you have, even Turbo and GT3 owners modify their cars like crazy. At some point.... when is enough, enough??

Thanks again for keeping us updated! Glad to hear that your car is strong and powerful. Once you dial her all in I am sure you will enjoy it even more. looking forward to future posts and updates.

jamesinger

400 miles per tank?
Is that 100% freeway?
That is insane, or I am getting really bad mileage!!

Hammerman501

Most of my miles are highway,I would estimate 80%. For several years I had a job that included a 60 mile roundtrip commute on an interstate highway. For the 1000 mile break-in I have been mostly driving on highways as well. In traffic the milage is more along the lines you are talking about.

bronz

can you give us a scoop what kind of break-in procedure you were instructed to follow?

jamesinger

^^^ that is amazing. Thanks for the reply.

I live in LA, so I never get to drive 5 miles without slowing on the freeway unless it is before 7am or after 8pm, now 7 days a week. I think that affects my mileage. A lot of my other driving is on ACH, so that is another factor. I noticed I get between 270-300 miles a tank but I also don't run it to E. When the light goes on, I start planning to get fuel without overthinking it too much.

A quick OT add, is when I had my tune on a 2.3 up from a 2.0 on an EVO VIII, the MPG didn't really change for daily driving because of the tune and the fuel trim wizardry, so I am just guessing that'd be the case on most cars when tuned for driveability over all out track performance or whatever.