How can a 911 3.4 have so much more HP than a 3.2 Boxster S?

[The Radium King]

this has got me thinking about a 996 3.4 intake manifold on the 3.2 with perhaps a cayman engine cover for the additional clearance required (or lower the engine) - I wonder if it has been done?

[JAAY]

Yes a 987 engine cover fits. I have one on my 3.4 conversion so I didn't have to lower the engine.

[The Radium King]

that would be the ultimate intake conversion then ...

987 air box - $250 used
987 engine cover - $100 used
996 3.4 intake manifold - $250 used
997 plenum - $50 new (you could use the 996 plenum, but one assumes the 997 part is an improvement)
996/997/987 throttle body - $100 used
987 maf housing - $100 jobber

$850.

get a softronic tune that let's you use a 987 maf housing - $700 on sale (or $50 labour at your local indy if a 996 3.4 x51 row pre-variocam+ tune will work).

finally, a $500 performance exhaust (topspeed or 987 S take-off) and a $200 underdrive pulley.

so, potentially 300 hp bolt-on (+50) for $1,600 to $2,250 - worth it?

[jaykay]

Originally Posted by The Radium King

that would be the ultimate intake conversion then ...

987 air box - $250 used
987 engine cover - $100 used
996 3.4 intake manifold - $250 used
997 plenum - $50 new (you could use the 996 plenum, but one assumes the 997 part is an improvement)
996/997/987 throttle body - $100 used
987 maf housing - $100 jobber

$850.

get a softronic tune that let's you use a 987 maf housing - $700 on sale (or $50 labour at your local indy if a 996 3.4 x51 row pre-variocam+ tune will work).

finally, a $500 performance exhaust (topspeed or 987 S take-off) and a $200 underdrive pulley.

so, potentially 300 hp bolt-on (+50) for $1,600 to $2,250 - worth it?

I tried to get softronic to give me a cayman MAF housing tune to no avail.

[itsnotanova]

Bump on this thread. I just switched motors back from a 3.4 to a 3.2 and I don't notice any real difference in power. I have a 3.4 intake, 987 air box,4 inch pulley, 996 ROW tune, headers and custom made exhaust. I question why Porsche even bothered with building a 3.4.

[jaykay]

Originally Posted by itsnotanova

Bump on this thread. I just switched motors back from a 3.4 to a 3.2 and I don't notice any real difference in power. I have a 3.4 intake, 987 air box,4 inch pulley, 996 ROW tune, headers and custom made exhaust. I question why Porsche even bothered with building a 3.4.

Wood,

Have you considered the Cayman intake plenums rather than 996s?

[Bigsmoothlee]

Originally Posted by JAAY

Yes a 987 engine cover fits. I have one on my 3.4 conversion so I didn't have to lower the engine.

Jaay, did you have trouble with the shifter cables being too short when you installed the 3.4 manifold without lowering the engine?

Which 987 engine cover did you use? Was it from a Cayman/Boxster S?

[golonaus]

Originally Posted by Bigsmoothlee

Jaay, did you have trouble with the shifter cables being too short when you installed the 3.4 manifold without lowering the engine?

Which 987 engine cover did you use? Was it from a Cayman/Boxster S?

dont know about Jaay,but In my install yes cables are too short
just a bit tho
Simple solution is to move shifter console about 1/2"
I drilled new mounting holes and shifter boot covered it
looks and works as it should
I'm curious how Jaay solved it too, tho
btw
I'm using cover from a cayman s

[JAAY]

I ran my cables under the intake manifolds.

[Bigsmoothlee]

Originally Posted by golonaus

same here
987 cover got nice bump in the middle. you just need to trim off some of the carpet padding

Excellent, thanks.

Originally Posted by JAAY

I ran my cables under the intake manifolds.

Did you use a 987 S cover or a standard 987 cover? I see both have raised bumps, I wonder if they're different?

I didn't think it was possible to run the cables under the manifold until now... Thanks

[JAAY]

I don't know what cover I used. I think there the same though.

[golonaus]

Originally Posted by JAAY

Yes a 987 engine cover fits. I have one on my 3.4 conversion so I didn't have to lower the engine.

same here
987 cover got nice bump in the middle. you just need to trim off some of the carpet padding

[jaykay]

Originally Posted by JAAY

Yes a 987 engine cover fits. I have one on my 3.4 conversion so I didn't have to lower the engine.

Jaay does the cayman cover mess with the soft top? Were you able to adapt ithe insulation cover to fit over it ?

[golonaus]

Originally Posted by jaykay

Jaay does the cayman cover mess with the soft top? Were you able to adapt ithe insulation cover to fit over it ?

no problem there
5 min job to remove excess sponge/isolation

[BYprodriver]

Originally Posted by The Radium King

this has got me thinking about a 996 3.4 intake manifold on the 3.2 with perhaps a cayman engine cover for the additional clearance required (or lower the engine) - I wonder if it has been done?

I doubt any of this is worth the loss of low RPM torque especially for 3.2L or less.

My 3.6L does fine with the original intake & 997 plenum T

[The Radium King]

would there be a loss? the taller stacks on the 3.4 manifold should improve intake tuning at lower rpm? but I guess intake tuning for a 3.4, not a 3.2 ...

[steved0x]

This is a very interesting discussion and I just found the other big thread by TRK on using the bigger TB and Plenum. Very interesting stuff.

Steve