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Anyone swap a 3.4 to 3.8 yet?

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Old 01-04-2019, 09:30 PM
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dporsche74
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Default Anyone swap a 3.4 to 3.8 yet?
Now my CPO is over and i see very low mileage 991 3.8 engine complete on Ebay for super cheap .. Has anyone installed the 3.8S engine into a 3.4 ?

What does it take to install a S engine like the old days ? All i can think of is the 3.8 computer with wiring harness and and 3.8 engine..


thanks much !!!
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Old 01-04-2019, 10:30 PM
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awrryan
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Originally Posted by dporsche74
Now my CPO is over and i see very low mileage 991 3.8 engine complete on Ebay for super cheap .. Has anyone installed the 3.8S engine into a 3.4 ?

What does it take to install a S engine like the old days ? All i can think of is the 3.8 computer with wiring harness and and 3.8 engine..


thanks much !!!
check with BGB Motor Sports in FL. They appear to work a lot on Caymans, but have been stuffing bigger OEM engines in them.
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Old 01-05-2019, 08:08 AM
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Originally Posted by awrryan


check with BGB Motor Sports in FL. They appear to work a lot on Caymans, but have been stuffing bigger OEM engines in them.
Very good advice here. A 3.8 with the PowerKit, and a few mods (filters, headers, exhaust) and you'd be quickly to 450 HP.........a 100 over your current base. That would be a hoot. And a sleeper.

Another option, if you have the time to wait, would be calling Jake at Flat 6 Innovations. He can easily take your current 3.4 to 4.0 or over. Bring cash. Lots of it.
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Old 01-05-2019, 09:51 AM
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You'd be creating a car worth nothing, and spending a lot of time and money doing it. Just upgrade to a faster car.
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Old 01-05-2019, 12:04 PM
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arter
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would be cheaper to trade your current base for the same year S and would maintain your future tradein values.
Check with BGB. I believe the install ( not counting the engine cost) is around $6000.
arter is offline  
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Old 01-05-2019, 10:11 PM
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Originally Posted by LexVan
Another option, if you have the time to wait, would be calling Jake at Flat 6 Innovations. He can easily take your current 3.4 to 4.0 or over. Bring cash. Lots of it.
I know he has a great reputation and this is only one sample out of many, but a close friend of ours who has a Raby 3.8 in his 986 Boxster has been having tons of issues with his engine. I'd avoid this route if you can.
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Old 01-05-2019, 11:55 PM
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Originally Posted by reacher
You'd be creating a car worth nothing, and spending a lot of time and money doing it. Just upgrade to a faster car.
You make a good point, but, if my engine went, I’d be all in. Of course, at that point, I’d be without an engine and would have no choice. Also, I have a base 991. Upgrading to a Carrera S x51 would be worth it for me if I need an engine replacement. Hmmmm, wonder if a gt3 engine would work.
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Old 01-05-2019, 11:58 PM
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Originally Posted by erko1905
I know he has a great reputation and this is only one sample out of many, but a close friend of ours who has a Raby 3.8 in his 986 Boxster has been having tons of issues with his engine. I'd avoid this route if you can.
Strange. Practically unheard of. There's more to your story.
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Old 01-06-2019, 06:12 AM
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Originally Posted by awrryan


You make a good point, but, if my engine went, I’d be all in. Of course, at that point, I’d be without an engine and would have no choice. Also, I have a base 991. Upgrading to a Carrera S x51 would be worth it for me if I need an engine replacement. Hmmmm, wonder if a gt3 engine would work.
It's extremely unlikely your engine will blow. Even if you put an S engine in a base, it'll still just be a base. I'd start looking for an S if I were you. The rule of thumb is to always trade up instead of doing heavy modification if there is a higher model that has what you want. Obviously if you wanted something that didn't already exist, that's a different story
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Old 01-06-2019, 11:45 AM
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Originally Posted by reacher
It's extremely unlikely your engine will blow. Even if you put an S engine in a base, it'll still just be a base. I'd start looking for an S if I were you. The rule of thumb is to always trade up instead of doing heavy modification if there is a higher model that has what you want. Obviously if you wanted something that didn't already exist, that's a different story
That rule of thumb is completely personal. Some of us enjoy tinkering and modifying the stuff we have rather than buying up.

Op, as mentioned bgb has a swap option but it's quite costly. https://rennlist.com/forums/991/892884-anyone-with-a-991-3-4l-want-to-upgrade-to-a-power-kit-gts-engine.html

It's a consideration if you love your baby but just want a little more juice.
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Old 01-06-2019, 02:19 PM
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If you’re asking what makes sense.... trade it in on a GTS or 991.1 GT3. Either will be cheaper and a lot more reliable. I’m not one to judge resale as I don’t care but you’re never going to be able to even sell it with a swap like that.
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Old 01-06-2019, 03:23 PM
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Originally Posted by erko1905
I know he has a great reputation and this is only one sample out of many, but a close friend of ours who has a Raby 3.8 in his 986 Boxster has been having tons of issues with his engine. I'd avoid this route if you can.
+1 I don't want to go into details but I know another problem engine (well, grenaded engine) from this shop that Raby has handled incredibly poorly.
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Old 01-06-2019, 04:46 PM
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Originally Posted by dporsche74
Now my CPO is over and i see very low mileage 991 3.8 engine complete on Ebay for super cheap .. Has anyone installed the 3.8S engine into a 3.4 ?

What does it take to install a S engine like the old days ? All i can think of is the 3.8 computer with wiring harness and and 3.8 engine..


thanks much !!!
OP - I have the wiring harness & some other bits from a 3.8 motor for sale if you choose to upgrade (PM me with any questions). As others have said, it will NOT be the cheaper route but I understand the “tinker” factor Good luck!
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Old 01-06-2019, 04:59 PM
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Originally Posted by erko1905
I know he has a great reputation and this is only one sample out of many, but a close friend of ours who has a Raby 3.8 in his 986 Boxster has been having tons of issues with his engine. I'd avoid this route if you can.
Not sure who this may be, but there’s been no reports here of such an instance. Based on this poster's location I can only think of one possible car. After a trip to his local mechanic, the car caught fire. I gave him over 1,000.00 worth of ancillary components to fix it- for free (4+ years after we saw the car last). Haven't heard much since then, and nothing recently, or at least in the last 3-4 months. We built that engine around 5+ years ago, IF thats the one. Can't think of any other that it could be.

I’d appreciate it if he could contact me.

As far as a supposed “grenaded” engine- no report of one of those either. We've had two "grenade" in the last 5 years, one was driver error (zinged it to 12,000 RPM) so either "this" is the "other one" or its something that wasn't ever reported to us. There are no current warranty claims, were none in 2018, and we haven't denied a single warranty claim since 2010.
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Old 01-06-2019, 05:15 PM
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Originally Posted by reacher
It's extremely unlikely your engine will blow. Even if you put an S engine in a base, it'll still just be a base. I'd start looking for an S if I were you. The rule of thumb is to always trade up instead of doing heavy modification if there is a higher model that has what you want. Obviously if you wanted something that didn't already exist, that's a different story
Only different between the base and the S is the engine and breaks (recognizing that I do not know if there is a difference in gearing in the transmission). I also agree it’s unlikely my engine will blow, but just thinking out loud
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