Has anyone figured out how to get more HP
#61
Get 3.8 Cayman, run with Joe and I, we're your friends too.
#62
Nordschleife Master
#63
Originally Posted by orthojoe
Are you saying that a swap to a 3.8DFI doesn't require any ECU changes? If true, that is a big deal in terms of ease, reliability, and ca smog
If you look into it, you'll find the 3.4 and 3.8 are very similar. They share the same crank and rods. The big difference is the bore. 97mm for the former and 102mm for the latter. If you look at Porsche's online parts manuals for 997.2 and 987.2 you can compare the two engines and see how they differ. Of coarse a big difference is hoses and connections because of the 180 degree orientation difference.
The 3.8 engine case also has to be modified in at least two ways that I know of. A hole has to be drilled and tapped for the front motor mount bracket. The water pump housing provides a guide and shows you exactly where to drill it. The bigge is the oil filter pedestal. The 997 oil filter would point into the drivers back in the 987, so it must be discarded and the case must be modified for the 987 pedestal. I'm not sure how to do this yet. I may buy a new 987 pedestal and compare to the 997 one and examine the case more. I do know it can be done without motor disassembly.
#64
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Folks,
Sorry to chime in so late but we are on the road testing at Watkins Glen. I feel that there is a lot of stuff that I need to reply to and I'm going to do it briefly and I am sure I will miss something.
1. ReadyKW - Email me or call me. It seems like you are going to go forward with this by yourself. It's not by any means rocket-surgery but you do have to completely undress a 3.4L and re-dress the 3.8L, with all 3.4 parts from fuel lines to coolant passages to oil manifolds, plugging passages, etc. Again, it's feasible but just call/email.
2. While it can be done that you can drop the 3.8L into the car without additional tuning, you need to tune the car. Furthermore, an X51 motor has variable length runners in the manifold tract and therefore requires knowing what to do with it, specific only to the 997.2 ECU file.
3. If someone wants to pay $150K for a Cayman with a GT3 motor, sign me up and I'll build it but I'm pretty sure people make fun of me behind my back for asking over $120K for anything Cayman. Yet other cars sell on the INTERNET for that. Go figure.
4. The 4.2 is a $36K engine conversion to your existing 3.4L DFI engine with a 6 month lead time that makes the most power of any naturally aspirated non-Cup motor i have ever seen. While I have only talked to the guys, their dyno runs are on the web site and they look strong. I bet it's an amazing piece but not legal for our racing so we can't use it. I remember talking to Charlie at L&N when we started pulling the motors apart in the end of 2009 and those guys know their stuff and he's a really nice guy.
5. It makes no sense to put a GT3 motor in a Cayman unless you absolutely have to have one. Then, if you do, like i said, call me.
6. What was 6? When all the engine people figured out what PMAG did several years ago to run the 3.99L RSR motor, then became the boring and stroking measures. The flat-6 RSR motor that was in the Daytona Prototypes was a 3.99L with a 3.6L crank and I'm assuming a 3.8L bottom end. Sound familiar? I got tired of waiting to have someone make me a special 3.8L DFI 9A1 piston so i could put a stock Porsche 3.6L crank shaft in a 3.8L DFI engine. I started asking for one in 2009 and no one would sell me one. So we are having them made and they will be done shortly because you can create a 4.0L from a 3.8L WITHOUT overboring! Again...you know the number to the shop.
Sorry for the quick reply but we have two days of testing Wed/Thursday and Porsche needs to win the Watkins Glen 6 Hour weekend this year or it's going to be a long season.
Thanks for the distance on the thread. I had to leave the shop but the car is awaiting the calipers, wheels and suede bits still. Stay tuned.
John
Sorry to chime in so late but we are on the road testing at Watkins Glen. I feel that there is a lot of stuff that I need to reply to and I'm going to do it briefly and I am sure I will miss something.
1. ReadyKW - Email me or call me. It seems like you are going to go forward with this by yourself. It's not by any means rocket-surgery but you do have to completely undress a 3.4L and re-dress the 3.8L, with all 3.4 parts from fuel lines to coolant passages to oil manifolds, plugging passages, etc. Again, it's feasible but just call/email.
2. While it can be done that you can drop the 3.8L into the car without additional tuning, you need to tune the car. Furthermore, an X51 motor has variable length runners in the manifold tract and therefore requires knowing what to do with it, specific only to the 997.2 ECU file.
3. If someone wants to pay $150K for a Cayman with a GT3 motor, sign me up and I'll build it but I'm pretty sure people make fun of me behind my back for asking over $120K for anything Cayman. Yet other cars sell on the INTERNET for that. Go figure.
4. The 4.2 is a $36K engine conversion to your existing 3.4L DFI engine with a 6 month lead time that makes the most power of any naturally aspirated non-Cup motor i have ever seen. While I have only talked to the guys, their dyno runs are on the web site and they look strong. I bet it's an amazing piece but not legal for our racing so we can't use it. I remember talking to Charlie at L&N when we started pulling the motors apart in the end of 2009 and those guys know their stuff and he's a really nice guy.
5. It makes no sense to put a GT3 motor in a Cayman unless you absolutely have to have one. Then, if you do, like i said, call me.
6. What was 6? When all the engine people figured out what PMAG did several years ago to run the 3.99L RSR motor, then became the boring and stroking measures. The flat-6 RSR motor that was in the Daytona Prototypes was a 3.99L with a 3.6L crank and I'm assuming a 3.8L bottom end. Sound familiar? I got tired of waiting to have someone make me a special 3.8L DFI 9A1 piston so i could put a stock Porsche 3.6L crank shaft in a 3.8L DFI engine. I started asking for one in 2009 and no one would sell me one. So we are having them made and they will be done shortly because you can create a 4.0L from a 3.8L WITHOUT overboring! Again...you know the number to the shop.
Sorry for the quick reply but we have two days of testing Wed/Thursday and Porsche needs to win the Watkins Glen 6 Hour weekend this year or it's going to be a long season.
Thanks for the distance on the thread. I had to leave the shop but the car is awaiting the calipers, wheels and suede bits still. Stay tuned.
John
#68
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#69
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#72
Originally Posted by BGB Motorsports
1. ReadyKW - Email me or call me. It seems like you are going to go forward with this by yourself. It's not by any means rocket-surgery but you do have to completely undress a 3.4L and re-dress the 3.8L, with all 3.4 parts from fuel lines to coolant passages to oil manifolds, plugging passages, etc. Again, it's feasible but just call/email.
Anyway, there is clearly a thirst for information regarding this. What does everyone think, new thread or continue this one? Mods?
#73
Three Wheelin'
#75
From what I've seen, 3.8 L will run with stock 3.4 ECU but the power you make will be pitifully little. Certainly not 408 or even 385 bhp. You need 3.8 L tune to take advantage of the switch.