Big Power Upgrades for 986 - How Much?
 

Hi All,
I am thinking about adding some power to my 986 this winter. The suspensionw rocks (PSS9) but I would likely need to upgrade brakes (easy enough).

The two avenues I am considering are
1) Jake Raby. He can bore out a 2.5 to 2.9 and makeover the mechanicals of the motor to make it more robust. He gets about 260 hp in this fashion (200 stock). Add a turbo and it's about 300 hp.

2) Farnbacherloles engine swap. They can install 3.6, 3.6 X51 or 3.8 powerplants in a Boxster.

Has anyone here researched or gone either avenue? I'm wondering just what the cost is of these types of conversions and whether or not you would recommend doing it in hindsight.

I have been toying with the idea of an engine swap also. Jake states that our stock engines aren't made for the pressure of a turbo or super charger. I have told myself if my engine blows, I will go up to at least a 3.6 but more likely 3.8. I haven't researched either yet as its a whole lot of $$$. I don't know about the FarnBache.. but I would have total confidence with Jake. I just don't know if I want to put 20k into my box I paid almost 13k for. Here is a link I found but after i do more research I will be able to give an opinion.

http://www.caranddriver.com/reviews/car/07q4/farnbacher_loles_cayman_gtr-specialty_file

http://www.europeancarweb.com/features/0701_ec_porsche_cayman_gtr/index.html

If you're going to add much more power, start with an "S" to begin with, for obvious reasons.

I'd go with the Raby 3.6 rebuild, based on the "S" 3.2...

Since you're asking, I would lean towards a Raby build, from a 3.2 to a 3.6.

:cheers:

Under 10k I did my 3.4 swap.

Raby 3.6 if my handgrenades, then it's guaranteed I'll never let her go.

Ditto, the Raby 3.6L, you are then getting an engine that has had most of the major failure modes addressed. His engines look like a good investment if you can do it,

Ed

:)

The 2.5 to 2.9 is a great engine, I can vouch as my wife's track boxster has one. It's tough as nails - it basically has been at every PCA autocross and DE event all season and other than a broken valve spring before Road America (no fault of Jake's - it was a new Porsche OE spring), it's knock on wood reliable.

On top of the time my wife spends driving it, I've had other instructors drive it in separate run groups to purposefully beat the crap out of the car, racking up hundreds of track miles every weekend.

But... all things considered, if you can get a 3.2 to start from, it would probably be cheaper and provide more bang for the buck than starting with the 2.5.

I just finished making up new MLS head gaskets to allow increasing the deck by .010" (these engines run a .027-.033" deck from the factory) to lower the compression, for turbo conversions. That and also because the lowest compression JE can make is about a 9.5:1 off their current FSR forgings, so something more is needed to get the compression down to run a meaningful amount of boost (to justify the cost of doing the turbo in the first place).

I have a TPC blower on mine, puts out around 270-280 hp. Lots of fun I'm contemplating changing the pulley and adding some liquid inter cooling for around 300hp. I think that's really sort of the hypothetical max you can squeeze out of a stock 2.5.

I'd like put a 3.6 in with superchargers in and catch a gt.

Regards, PK

"I have a TPC blower on mine, puts out around 270-280 hp. Lots of fun I'm contemplating changing the pulley and adding some liquid inter cooling for around 300hp."

Sounds like fun, and it adds another data point about how our stock engines behave with forced induction. Is there much spool-up time to make power with the blower? Also, do you have any plans if you get a "D" chunk or other major engine failure?

Ed

:cheers:

I like the idea of of the LN sleeves, as it's a surefire way to eliminate the possibility of cylinder bore failure. Their IMS update is great as well. However, while the 3.2 heads allegedly flow plenty to allow for a 400CC increase in displacement (which could be improved with some head work anyway), what you don't get by doing a 3.6 build off a 3.2 block is VarioCam Plus, which is a significant improvement over basic VarioCam.

If money were no object, what I think is the best ticket is to bore out a 3.6 to a 3.8 with LN sleeves, do the IMS update, uprated rods, bolts, and other things, and wind up with a 3.8 WITH VarioCam Plus that should prove bulletproof. You will have to run a 7.8 DME to make this work, however.

I think a stock M97 3.8 is a pretty good choice as well. The M97 series motor (which includes only the 3.8, to the best of my knowledge) does not seem to suffer the failures that plagued the M96. For that matter (and someone please correct me if I am wrong), I don't think I've heard of a cylinder bore failure in a 3.6 either. Now, IMS failures are a whole different story, but that can be solved with LN's IMS update.

I just finished fixing a 3.6.

The only block I haven't seen is a 3.8 block, so I don't know if they made any changes. As far as I'm concerned, a 3.6 block is identical to a 3.4 block.

Well so much for my idea LOL. I know that the 3.4 and 3.6 share the same bore, the 3.6 achieving it's greater displacement via a longer stroke, but some evidence would seem to indicate that even if Porsche didn't change the case halves at all, that their process or control over the process improved, as there seem to be plenty of D-chunked 3.4s, and not so many 3.6s.