Impressions of my 981 Boxster w/ BGB 3.8L 991S conversion
05-21-2014, 06:28 AM
#46
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Okay here's the next question here for BGB...would this conversion make sense to do in an 981S? I mean I would think it would and actually some things such as the brakes would not be needed to upgrade as much. Engine isn't it the same as the base 991 Carrera so how would the conversion be different if any/or as much? Cost maybe? Performance would be the same no? Interesting concept for sure and I am sure Porsche is saying WTF to themselves as well as maybe considering doing this if enough converted cars hit the road I am sure of that part!
Anyway will await answers/thoughts.
Great car tho Lee! Thumbs up!
Anyway will await answers/thoughts.
Great car tho Lee! Thumbs up!
05-25-2014, 08:16 PM
#47
John- I'm interested in this conversion for a 981S Cayman. Please PM pricing and timeline. I should have a car to ship to you next week.
Ladies and Gents, First and foremost, I want to thank Lee for having the faith in us to do this work, for his patience during what was a very hard season running 3 cars and building more AND for his gracious writeup on the Rennlist.com site. I had to renew our sponsorship, so I apologize for chiming in late. I will attempt to answer all questions as best as possible per my recollection. 1. This job is somewhat really hard to do when trying to slam any type of 997.2 engine into a 987.1 car. A lot would be invested in pinning out control units, running the DFI pump, etc and therefore we have stayed away from crossing generations. If you have a 987.1, you need a 997.1 X51 swap and that's a cap of 385crank hp and 300lb/ft. The 997.2 engines are much more robust, reliable and worth the bang for the buck. The most power that you could deliver to a 987.2 would be with an X51 9A1 DFI engine. Lee's car gets the benefit of aggresive tuning from the stock 991 software and it's rated at 400 crank hp and 325 lb/ft of torque at the crank and as you can see from the dyno comparison to our 991, it's awful close. BUT withou a Motec dash, it's hard to control the variable intake runners that are really what make the X51 engine. The 997.2 "Power Kit' head is not really the CNC ported head we think it is. the valves aren't different nor are the camshafts. HOwever, the cost of the X51 engine core has come down from $25K to $12K. So that's promising. 2. We did dyno the first car. that dyno graph is attached. I was in a rush to get Lee's car back to him and I was not there to dyno it. The graph from the Cayman with the same parts however is attached. 3. Unfortunately Lee's DME is stock and is in need of a flash. It will be a few months still before the new 991/981 software from Siemens is hacked. When it is, all these cars need files. They're totally stock and the only reason I was able to crack the code on the tuning WITHOUT tuning is because the new cars use a MAP sensor, not a MAF sensor. Therefore, the ECU is even more ignorant to the fact that it has a fire breathing dragon in the hole as opposed to the little 2.7L DFI gerbil. Lee's car got air filters but is in need of a bigger throttle body, plenum and a race file. The first Cayman we built apparently wasn't powerful enough and that car's owner was kind enough to commission us to install the 991 Power Kit heads. NOW THAT IS A MOTOR. The heads are actually ported and it comes with bigger valves and a different cam shaft. It's a worthwhile job. I appreciate the kind words and support from the people on here. If you have further questions, please call or write. I will try and chime in more often. Thanks. 
05-26-2014, 12:37 AM
#48
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05-30-2014, 09:40 AM
#49
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The black donor car that I had found for you would have been perfect. I am going to proceed with buying it and building it into a 3.8L conversion. I got your email about switching gears and buying a 430. I did not reply though. Good luck with the car.
Last edited by BGB Motorsports; 05-30-2014 at 11:50 AM.
06-24-2014, 01:16 PM
#51
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Folks,
Since this thread started, Lee's car has come back for some more bolt-ons. It got X73 sport suspension, Cargraphic manifolds, Sport Mufflers and an IPD plenum. The car makes 350rwhp on the dyno. Lee is loving it. He will chime in shortly.
We however are desperate for another build customer. I can produce referrals, I can put you in touch with other owners...someone please sign up!
How about this one as a donor car? Black, black, black...and Sports Plus!
Since this thread started, Lee's car has come back for some more bolt-ons. It got X73 sport suspension, Cargraphic manifolds, Sport Mufflers and an IPD plenum. The car makes 350rwhp on the dyno. Lee is loving it. He will chime in shortly.
We however are desperate for another build customer. I can produce referrals, I can put you in touch with other owners...someone please sign up!
How about this one as a donor car? Black, black, black...and Sports Plus!
06-29-2014, 11:50 AM
#53
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Low relative to what? These cars are still stock with stock firmware, catalytic converters, stock intakes and no race gas. The numbers are the same for that of a 991 3.8L Carrera S as we have done the back to back comparison. So they aren't low relative to that.
They might be low relative to a car with a tuned file, race gas, pulleys, race intake, etc...which is a 400rwhp number. So yes, given that they are stock, they are low relative to a tuned race car.
Thanks.
06-29-2014, 03:46 PM
#54
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Sorry. I didn't mean to imply anything. It was just that he had added intake/exhaust mods and was still sitting at stock hp. These engines must really be software sensitive...
06-30-2014, 10:35 AM
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I just picked up my BGB built 981 Cayman (Honey Badger -- evil sister of Badger) and took her out to Road Atlanta and VIR for four days of bonding. John and I talked about the build and I only had two answers "yes" and "I want that". It is almost complete for Stage 1, just waiting for the splitter to be fabricated. I do a lot of track driving so she was designed as a street legal race car. She is not fun on long trips on the freeway and my hands were buzzing after a 2 hour jaunt. A few high level specs include: 3.8L conversion with an upgraded manifold - headers and exhaust (Cargraphic race stuff), 911S brakes, Full Suspension, Aerodynamics, Seats, electronics, upgraded PDK, wheels and tires .... etc., too much to mention. Essentially no budget. She is at her core a Cayman 981 chassis that thinks it is a 911S / GT3 and lots of special other stuff that is now available and made from machined billet. All parts are Porsche unless there is something better for a specific purpose.
She acquitted herself well in her first 4 track days and solved what I jokingly call "the Corvette problem" (big engine cars that own the long straights: Turbos, GT3s, Ferraris, Lamborghinis, Mustangs, Vipers, CVTs, you know who they are). ... now they can't get away and Caymans own the corners. This was my first 4 track days with a lot of new things going on but Honey Badger hit 155 on the back straight at Road Atlanta and we were able to turn laps in the 1:39 [edited, yipes that would have been fast] range while never being passed. At VIR we turned a 2:11 and were into the low 150s after the "no tree turn" (turn 12) ... the old oak tree is gone. She has more speed but not enough track to figure out what that is. This was my first outing at VIR so I took along an instructor who is an ex pro racer and he loved the car and got me up to speed quickly. Lots of passing and not much getting passed. (he tricked me by making me do 4 things at once to break my concentration so I pointed 6 cars by ... he admitted to the trick because I wasn't getting passed and he wanted to see how I managed traffic in free passing coming up from the rear. Then he just said "now go get them". He was a fun and precise instructor and when we saw a Ferrari up ahead he said "looks like horse meat is on the menu" another time "oh look a tricked out Viper, that will make a nice scalp". I was gaining on a tricked out Mustang that I could keep with on the straights because I had a higher exit speed and when we entered turn 1 he said "now he is in your world" and he was dispatched between 3 and 4.
As to the ECU question. John was getting the incorrect ECU from the vendor and finally got the correct one that he can appropriately flash to the correct performance settings for the engine. (He is a master at this and suspension/chassis setup) I'm taking the car down to BGB today to have her looked over and a couple more things added. I have a busy schedule with DAs through the year and club racing starting in the Fall. I will be all over the place so if you see me come up and introduce yourself.
Here are a few pictures.
Cheers,
Craig
She acquitted herself well in her first 4 track days and solved what I jokingly call "the Corvette problem" (big engine cars that own the long straights: Turbos, GT3s, Ferraris, Lamborghinis, Mustangs, Vipers, CVTs, you know who they are). ... now they can't get away and Caymans own the corners. This was my first 4 track days with a lot of new things going on but Honey Badger hit 155 on the back straight at Road Atlanta and we were able to turn laps in the 1:39 [edited, yipes that would have been fast] range while never being passed. At VIR we turned a 2:11 and were into the low 150s after the "no tree turn" (turn 12) ... the old oak tree is gone. She has more speed but not enough track to figure out what that is. This was my first outing at VIR so I took along an instructor who is an ex pro racer and he loved the car and got me up to speed quickly. Lots of passing and not much getting passed. (he tricked me by making me do 4 things at once to break my concentration so I pointed 6 cars by ... he admitted to the trick because I wasn't getting passed and he wanted to see how I managed traffic in free passing coming up from the rear. Then he just said "now go get them". He was a fun and precise instructor and when we saw a Ferrari up ahead he said "looks like horse meat is on the menu" another time "oh look a tricked out Viper, that will make a nice scalp". I was gaining on a tricked out Mustang that I could keep with on the straights because I had a higher exit speed and when we entered turn 1 he said "now he is in your world" and he was dispatched between 3 and 4.
As to the ECU question. John was getting the incorrect ECU from the vendor and finally got the correct one that he can appropriately flash to the correct performance settings for the engine. (He is a master at this and suspension/chassis setup) I'm taking the car down to BGB today to have her looked over and a couple more things added. I have a busy schedule with DAs through the year and club racing starting in the Fall. I will be all over the place so if you see me come up and introduce yourself.
Here are a few pictures.
Cheers,
Craig
Last edited by cobrienmx; 07-01-2014 at 06:29 AM. Reason: Incorrect lap time ...yipes!!
07-03-2014, 06:14 PM
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If you think about the fact that we were able to achieve 415rwhp and 312lb/ft to the wheels with a stock X51 997.2 Power Kit engine and all of our bolt ons, tuning specifically, it is rather impressive.
John
07-04-2014, 01:06 AM
#59
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It's okay...I probably should have given you more slack but I am always protective of horsepower numbers because I don't ever overestimate rwhp and rqtq numbers. I think it's the catholic guilt. To answer your question though or to further the notion you have, absofrigginlutely. While motors have gotten so efficient and while motors have gotten so powerful, it still remains that the file has a lot of hidden potential that you just don't get on the street car that say...might be in the firmware in the GT3.
If you think about the fact that we were able to achieve 415rwhp and 312lb/ft to the wheels with a stock X51 997.2 Power Kit engine and all of our bolt ons, tuning specifically, it is rather impressive.
John
If you think about the fact that we were able to achieve 415rwhp and 312lb/ft to the wheels with a stock X51 997.2 Power Kit engine and all of our bolt ons, tuning specifically, it is rather impressive.
John
07-04-2014, 03:25 AM
#60
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man, that honey badger car is sexy....