Engine Upgrade - Boxster S Engine vs oem 2.5l engine

[JBW]

Hi from OZ!

Sad story - started an upgrade project for a 986 1997 Boxster - but bought a Tiptronic car- vs Manual

Obviously want the car to be manual for track!

Porsche Dealer who started the upgrade had estimated the tip to manual conversion would cost approx $AUS 2,500 extra

- pedal box, cables etc

- this was factored by me into the purchase of the car (not bought from the dealer)

- I sold the Tip in exchange for a 5-spd box

Accessed a Boxster S engine, bored to 3.4l & fitted with Sports cams etc -Porsche X51 package

- circa 260kw

Now all involved are worried as its an ex-TIP, the cost to do the complete manual convert could be a huge unknown & further, we will never be sure all the car’s electronics will be “talking to each other” – ie ABS, Eng Mngmt, etc

Situation:

- worked 3.4l engine sitting on wooden blocks in the car – ie not connected to transmission etc

- was a big job to strip the car down & make space for the 3.4 l engine!

- Dealer got it to start

- manual 5spd box ready - will need upgraded clutch/flywheel

-manual wiring harness accessed – but looks a little tired

Was using the Tiptronic to start a fatal decision?

I'm now "half pregnant" - ie will cost real $$$ to convert back to original Tip car & sell!

- or cost a potential huge $$$ to complete as per plan

appreciated

Justin :)

[txhokie4life]

Hi from OZ!

Sad story - started an upgrade project for a 986 1997 Boxster - but bought a Tiptronic car- vs Manual

Obviously want the car to be manual for track!

Porsche Dealer who started the upgrade had estimated the tip to manual conversion would cost approx $AUS 2,500 extra

- pedal box, cables etc

- this was factored by me into the purchase of the car (not bought from the dealer)

- I sold the Tip in exchange for a 5-spd box

Accessed a Boxster S engine, bored to 3.4l & fitted with Sports cams etc -Porsche X51 package

- circa 260kw

Now all involved are worried as its an ex-TIP, the cost to do the complete manual convert could be a huge unknown & further, we will never be sure all the car’s electronics will be “talking to each other” – ie ABS, Eng Mngmt, etc

Situation:

- worked 3.4l engine sitting on wooden blocks in the car – ie not connected to transmission etc

- was a big job to strip the car down & make space for the 3.4 l engine!

- Dealer got it to start

- manual 5spd box ready - will need upgraded clutch/flywheel

-manual wiring harness accessed – but looks a little tired

Was using the Tiptronic to start a fatal decision?

I'm now "half pregnant" - ie will cost real $$$ to convert back to original Tip car & sell!

- or cost a potential huge $$$ to complete as per plan

appreciated

Justin :)

There is a used 6 speed tranny on Ebay for about $2k (US), not sure how much it would cost to ship it.

It's from a 996, but believe it will work with a 3.2L S engine.

m

[Tool Pants]

Don't know anyone who has done a tip to manual conversion. Not saying it cannot be done. You can do almost anything if you are willing to spend the money. People who have put in a 996 3.4 have used the Boxster 5 speed with no problems - it can handle the torque. You don't want a 996 transmission because you will have 6 reverse gears.

[usaf-lt-g]

If the engine that was being replaced came from a 3.2 Boxster S, the fact that it was bored to a 3.4 specification shouldn't matter... it's still a 3.2 S engine. That would mean that as a plug-and-play solution, you would need to fit it was a standard 6-speed manual transmission (as the boxster S uses a 6-speed manual transmission).

However, since the original car was a 1997 Boxster, I don't believe E-Gas was introduced yet (essentially the fly-by-wire). The engine, would in my guess, already contain the throttle body assembly with e-gas, however, the pedal and electronics in the driver's foot pedal bay would not be present. So the pedal assembly for e-gas would likely also need to be replaced.

The dual-mass flywheel, and clutch assembly with pressure plate would need to also come from a Boxster S, and be replaced, along with the shifting cables and linkages necessary to swap in the 6-spd shifter.

It might just be my opinion, but I don't think hooking up a 5-spd transmission to a Boxster S engine is even a possibility without some serious re-workage of parts. Would be MUCH easier to swap in the e-gas and 6-spd trans. Because the engine is bored to a 3.4 specification, however, it may be necessary to look for a heavier duty flywheel / clutch assembly that can support the torque of the increased size of the engine.

My 2 cents

[JBW]

Don't know anyone who has done a tip to manual conversion. Not saying it cannot be done. You can do almost anything if you are willing to spend the money. People who have put in a 996 3.4 have used the Boxster 5 speed with no problems - it can handle the torque. You don't want a 996 transmission because you will have 6 reverse gears.

Many thanks :)

Yes - it is just a question of dollars.

But the issue is being advised using a TIP to start with was ok, was a fatal error re $$ - yes or no?

- will take forever to rtn to manual trim - ie replace entire wiring harness I am told, etc etc

Yes - I plan to use the Boxster 5 spd box I have

cheers

[JBW]

If the engine that was being replaced came from a 3.2 Boxster S, the fact that it was bored to a 3.4 specification shouldn't matter... it's still a 3.2 S engine. That would mean that as a plug-and-play solution, you would need to fit it was a standard 6-speed manual transmission (as the boxster S uses a 6-speed manual transmission).

However, since the original car was a 1997 Boxster, I don't believe E-Gas was introduced yet (essentially the fly-by-wire). The engine, would in my guess, already contain the throttle body assembly with e-gas, however, the pedal and electronics in the driver's foot pedal bay would not be present. So the pedal assembly for e-gas would likely also need to be replaced.

The dual-mass flywheel, and clutch assembly with pressure plate would need to also come from a Boxster S, and be replaced, along with the shifting cables and linkages necessary to swap in the 6-spd shifter.

It might just be my opinion, but I don't think hooking up a 5-spd transmission to a Boxster S engine is even a possibility without some serious re-workage of parts. Would be MUCH easier to swap in the e-gas and 6-spd trans. Because the engine is bored to a 3.4 specification, however, it may be necessary to look for a heavier duty flywheel / clutch assembly that can support the torque of the increased size of the engine.

My 2 cents

WOW - that is worth far more than 2cents - thanks a "million" :)

Dealer was ok that the 5spd box that I have - ex 1999 2.5l Boxster would be ok with the 3.2 - both re fitment & ability to handle torque - so will raise your point with them re 6 spd box - very curious indeed.

Has me even more worried now!! - over & above the whole tip to man conversion.

Yes - re the e-gas & throttle issue. We knew this had to be re-worked & has been done successfully already, back to suit the non e-gas version

Have started work on single mass flywheel & race clutch - both to suit the 5 spd box thou.....

Finally - what is your view on the whole tip to manual conversion - the killer seems to be the wiring system

- never being able to get all the components thereof to talk together......engine mngmt, ABS, lights, A/C etc

many thanks

Justin

[catmanluge]

I have a 3.4 non egas Throttle body and ram tube if you need one?

[JBW]

many thanks - but we are ok there

cheers Justin

[usaf-lt-g]

WOW - that is worth far more than 2cents - thanks a "million" :)

Dealer was ok that the 5spd box that I have - ex 1999 2.5l Boxster would be ok with the 3.2 - both re fitment & ability to handle torque - so will raise your point with them re 6 spd box - very curious indeed.

Has me even more worried now!! - over & above the whole tip to man conversion.

Yes - re the e-gas & throttle issue. We knew this had to be re-worked & has been done successfully already, back to suit the non e-gas version

Have started work on single mass flywheel & race clutch - both to suit the 5 spd box thou.....

Finally - what is your view on the whole tip to manual conversion - the killer seems to be the wiring system

- never being able to get all the components thereof to talk together......engine mngmt, ABS, lights, A/C etc

many thanks

Justin

Well you're going to have a couple of other challenges where wiring is concerned. #1, you're going to have replace the OBC, which i'm assuming you got with the new engine yes? I'm not 100% positive on this or not, but the instrument gauge cluster you have in your car, and that of the cluster found in a boxster S are 2 different versions... I believe it's similar to people who have wanted to swap in the 996 cluster in their boxsters, but I'm not 100% positive. That may be something you need to research more. The new 3.2 L OBC will be configured to a 3.2L's specs. However, because you have bored the engine, you will likely need to find an indy shop capable of "tuning" the engine. The MAF may need to be re-mapped among other things to fully take advantage of the performance specs.

The A/C controls (HVAC) control unit should be plug and play, I don't see there being anything different between these modules.

If the car has not been equpped with the "third radiator" already... you'll definately also want to make sure that gets installed as well. The 3.2S comes stock with 3 radiators, with the third in the middle. Has the car already been fitted with a Boxster S front bumper? Not sure if it's 100% necessary to put the S bumper on, however, that particular bumper has an air opening for cooling of the third radiator. Obviously the lines also have to be run to this radiator.

While we're at it, we might as well discuss the brakes and suspension. The S uses bigger rotors (cross-drilled) on both the fronts and rears, as well as larger calipers and pads among other things. It "may" be easier to purchase the "BREMBO" big brake kit, rather than trying to find Boxster S parts for all of it. You'll get the same if not better performance out of them, and it may cost less in the long run than having to hunt down all the parts. Just my thoughts there.

The suspension... the rear and front sway bars are more robust than a standard boxster, along with the linkage. These can be swapped out, and should help with overall stability. Since neither the S or the standard boxster were really designed for a larger engine like the 3.4 (at least on your year and model you're working on), and considering you're specing the car out for race... I would also suggest a more heavy duty engine mount. There are articles on how to swap in the 996 engine mount, which i believe would suit your purpose. There are some aftermarket ones that are out there, however, I have heard bad reviews on them and them causing more problems rather than fixing them.

As for the ABS, I'm not entirely sure as to the differences, someone else would need to chime in to give you some sound advice there.

One other thing you really should consider... again, with the intent of "racing" in mind. Replace the factory 3.2S AOS (Air Oil Separator) that's on the engine with larger more robust MotorSports AOS. It's a 2 compartmental true AOS as opossed to the factory ones that come on both the non-S and S engines, and it's meant for higher G-Forces (especially on cornering). Last time I checked, Sunset Imports can get the MotorSports AOS (which is a special Porsche order item) for $150, which isn't too bad all things considered.

Hope this helps. cheers

[JBW]

WOW - that is worth far more than 2cents - thanks a "million" :)

Dealer was ok that the 5spd box that I have - ex 1999 2.5l Boxster would be ok with the 3.2 - both re fitment & ability to handle torque - so will raise your point with them re 6 spd box - very curious indeed.

Has me even more worried now!! - over & above the whole tip to man conversion.

Yes - re the e-gas & throttle issue. We knew this had to be re-worked & has been done successfully already, back to suit the non e-gas version

Have started work on single mass flywheel & race clutch - both to suit the 5 spd box thou.....

Finally - what is your view on the whole tip to manual conversion - the killer seems to be the wiring system

- never being able to get all the components thereof to talk together......engine mngmt, ABS, lights, A/C etc

many thanks

Justin

Well you're going to have a couple of other challenges where wiring is concerned. #1, you're going to have replace the OBC, which i'm assuming you got with the new engine yes? I'm not 100% positive on this or not, but the instrument gauge cluster you have in your car, and that of the cluster found in a boxster S are 2 different versions... I believe it's similar to people who have wanted to swap in the 996 cluster in their boxsters, but I'm not 100% positive. That may be something you need to research more. The new 3.2 L OBC will be configured to a 3.2L's specs. However, because you have bored the engine, you will likely need to find an indy shop capable of "tuning" the engine. The MAF may need to be re-mapped among other things to fully take advantage of the performance specs.

The A/C controls (HVAC) control unit should be plug and play, I don't see there being anything different between these modules.

If the car has not been equpped with the "third radiator" already... you'll definately also want to make sure that gets installed as well. The 3.2S comes stock with 3 radiators, with the third in the middle. Has the car already been fitted with a Boxster S front bumper? Not sure if it's 100% necessary to put the S bumper on, however, that particular bumper has an air opening for cooling of the third radiator. Obviously the lines also have to be run to this radiator.

While we're at it, we might as well discuss the brakes and suspension. The S uses bigger rotors (cross-drilled) on both the fronts and rears, as well as larger calipers and pads among other things. It "may" be easier to purchase the "BREMBO" big brake kit, rather than trying to find Boxster S parts for all of it. You'll get the same if not better performance out of them, and it may cost less in the long run than having to hunt down all the parts. Just my thoughts there.

The suspension... the rear and front sway bars are more robust than a standard boxster, along with the linkage. These can be swapped out, and should help with overall stability. Since neither the S or the standard boxster were really designed for a larger engine like the 3.4 (at least on your year and model you're working on), and considering you're specing the car out for race... I would also suggest a more heavy duty engine mount. There are articles on how to swap in the 996 engine mount, which i believe would suit your purpose. There are some aftermarket ones that are out there, however, I have heard bad reviews on them and them causing more problems rather than fixing them.

As for the ABS, I'm not entirely sure as to the differences, someone else would need to chime in to give you some sound advice there.

One other thing you really should consider... again, with the intent of "racing" in mind. Replace the factory 3.2S AOS (Air Oil Separator) that's on the engine with larger more robust MotorSports AOS. It's a 2 compartmental true AOS as opossed to the factory ones that come on both the non-S and S engines, and it's meant for higher G-Forces (especially on cornering). Last time I checked, Sunset Imports can get the MotorSports AOS (which is a special Porsche order item) for $150, which isn't too bad all things considered.

Hope this helps. cheers

many thanks again :)

apologies for delayed reponse

Really feel we have bitten off more than we can chew here

- really should have started with a mna S & upgraded form there

- not a 97 Tip

- bad advice from Dealer

thks again

J