Go Back   986 Forum - The Community for Porsche Boxster & Cayman Owners > Porsche Boxster & Cayman Forums > Boxster General Discussions

Post Reply
 
LinkBack Thread Tools Display Modes
Old 08-07-2010, 10:07 PM   #1
Registered User
 
Join Date: Oct 2008
Location: Gilbert, AZ
Posts: 266
Boxster Subaru conversion interest? (Now with Audi V8 content)

I'm doing a Boxster/Subaru engine conversion and I was wondering if there is an interest in a build thread here. Not sure what the demographic is here or whether most are purists, but if people are interested in watching, I'd be happy to post up some information/pictures as I go along.


Last edited by kcpaz; 12-01-2013 at 09:19 PM.
kcpaz is offline   Reply With Quote
Old 08-07-2010, 10:35 PM   #2
Registered User
 
roadracer311's Avatar
 
Join Date: May 2007
Location: San Francisco, CA
Posts: 218
Boxster engine in a Subaru or Subaru engine in a Boxster?
__________________
2003 Boxster S
1995 Ferrari F355 Spider
San Francisco, CA
roadracer311 is offline   Reply With Quote
Old 08-08-2010, 02:36 AM   #3
Registered User
 
Join Date: Jul 2005
Location: Preston, CT
Posts: 100
Send a message via AIM to 986rgt
Sure, there's always SOMEONE interested. If you are talking a Subie engine in a Boxster, I'm sure there would be more interest than the other way around. Are you gonna try a WRX motor or a Legacy H6 motor? You would probably have less trouble with a 3.6R swap as you would not have to worry about intercooler placement. Either way, it sounds like it will be quite the project. Keep us informed.

Steve
986rgt is offline   Reply With Quote
Old 08-08-2010, 04:42 AM   #4
Registered User
 
Join Date: Nov 2007
Location: Chicago suburbs
Posts: 1,675
I'm a "purist", but I think a swap like this would appeal to a number of folks out there as an inexpensive alternative to a blown M96 engine. Plus it is a "boxer" configuration, so it's far better than some domestic transplant
__________________
JGM
2002 Boxster S
1973 911 Green FrankenMeanie
PCA DE Instructor circa '95
jmatta is offline   Reply With Quote
Old 08-08-2010, 05:21 AM   #5
Carnut
 
AndyA6's Avatar
 
Join Date: May 2010
Location: Utah
Posts: 775
I'd like to see this!
__________________
'14 Boxster
AndyA6 is offline   Reply With Quote
Old 08-08-2010, 06:25 AM   #6
Porscheectomy
 
Join Date: Mar 2006
Location: Seattle Area
Posts: 3,011
Quote:
Originally Posted by kcpaz
I'm doing a Boxster/Subaru engine conversion and I was wondering if there is an interest in a build thread here. Not sure what the demographic is here or whether most are purists, but if people are interested in watching, I'd be happy to post up some information/pictures as I go along.
If it's a Subaru engine in the Boxster, what engine are you using? I don't think I'd like the 2.0 turbo from my WRX in my Boxster as much as I like my 3.2. The Porsche engine has a much wider torque band and has so much more character. The Impreza engine, as fun as it is, is more like an on/off switch in comparison.

I'd also think the gearing of the Boxster would need to be altered. The WRX has short gearing and it's still easy to catch the engine off boost going around sharp corners. The Porsche has taller gearing in general.

Last edited by blue2000s; 08-08-2010 at 06:27 AM.
blue2000s is offline   Reply With Quote
Old 08-08-2010, 11:08 AM   #7
Registered User
 
Join Date: Oct 2008
Location: Gilbert, AZ
Posts: 266
Just to clearify, I will be putting an STI motor, into a Boxster S that I bought with a blown motor. Why anyone would go the other way around is beyond me...
kcpaz is offline   Reply With Quote
Old 08-08-2010, 03:46 PM   #8
Registered User
 
Join Date: Oct 2008
Location: San Diego
Posts: 434
Interested. I look forward to seeing more.
__________________
1999 Carrera 4 • Aero kit • 4" UD Pulley
My Corvette doesn't leak oil... it sweats horsepower.
sd_boxster is offline   Reply With Quote
Old 08-08-2010, 04:17 PM   #9
Registered User
 
Join Date: Jul 2004
Location: Houston, Texas
Posts: 7,243
Yup. Interested!
RandallNeighbour is offline   Reply With Quote
Old 08-08-2010, 06:26 PM   #10
Registered User
 
The Radium King's Avatar
 
Join Date: Apr 2010
Location: Canada
Posts: 3,121
fyi, there is a thread in another forum (914 i believe) where a capable-sounding fellow was looking into putting an ls1 v8 into the boxster. while that may sound a bit silly, the ls1 is about the same weight and dimesions as the m96. most of the thread goes on about all the work required to modify/fabricate bell housings and starter locations, but one of the interesting side notes of the whole thing is that the cayanne and audi v8's are both direct bolt-ons to the boxster transmissions. the author of the thread actually admits that an audi or cayanne conversion would be much simpler, but didn't pursue it as he couldn't afford to buy the engine (an ls1 is much cheaper). apparently the audi or cayanne would be less expensive in the long run given that transmission modifications are not required.

long story short, have a look at putting an audi v8 in there - might be easier.
The Radium King is offline   Reply With Quote
Old 08-08-2010, 08:43 PM   #11
Registered User
 
Join Date: Jul 2009
Location: Kansas
Posts: 83
very interested. keep us informed
__________________
1983 928 S Euro- fun to work on
2002 Boxster- fun to work on, being able to drive it is a bonus
al83s is offline   Reply With Quote
Old 08-09-2010, 12:03 PM   #12
Registered User
 
Join Date: Oct 2008
Location: Gilbert, AZ
Posts: 266
Quote:
Originally Posted by The Radium King
fyi, there is a thread in another forum (914 i believe) where a capable-sounding fellow was looking into putting an ls1 v8 into the boxster. while that may sound a bit silly, the ls1 is about the same weight and dimesions as the m96. most of the thread goes on about all the work required to modify/fabricate bell housings and starter locations, but one of the interesting side notes of the whole thing is that the cayanne and audi v8's are both direct bolt-ons to the boxster transmissions. the author of the thread actually admits that an audi or cayanne conversion would be much simpler, but didn't pursue it as he couldn't afford to buy the engine (an ls1 is much cheaper). apparently the audi or cayanne would be less expensive in the long run given that transmission modifications are not required.

long story short, have a look at putting an audi v8 in there - might be easier.

If you are talking about Brad Roberts, I know him and I know he's working on the LS conversion into a Boxster. We have talked at length about it. Bottom line, he is going that direction, and I am going the Subaru direction. The problem with the Audi/Porsche V8 is they are HUGE with their DOHC 32 valve design, and massively top heavy. Also, engine management could get expensive. In both of these cases, the Subaru and even LS motors are better for the Boxster than the German V8. No don't even get me stated on the cost of replacement/upgrade parts...

It sounds like there is some interest in atleast watching the project here so I will post up some pictures as I go.

Last edited by kcpaz; 09-04-2010 at 01:37 PM.
kcpaz is offline   Reply With Quote
Old 08-09-2010, 12:22 PM   #13
Registered User
 
Perfectlap's Avatar
 
Join Date: Nov 2004
Location: New Jersey
Posts: 8,709
A Cayenne engine in a Boxster sounds interesting. A V8 Audi engine sounded interesting until I spoke to my Porsche Indy who could not have more bad things to say about their engines after I mentioned an interest in buying an R8 once the prices had come down.
Subi Boxer engine would be pretty bad ass. A guy in one of the many autocross clubs around here made some exhaust mods to his and it sounded like a .50 caliber cannon.
__________________
GT3 Recaro Seats - Boxster Red
GT3 Aero / Carrera 18" 5 spoke / Potenza RE-11
Fabspeed Headers & Noise Maker
BORN: March 2000 - FINLAND
IMS#1 REPLACED: April 2010 - NEW JERSEY -- LNE DUAL ROW
Perfectlap is offline   Reply With Quote
Old 08-09-2010, 12:37 PM   #14
Registered User
 
Join Date: Oct 2008
Location: Gilbert, AZ
Posts: 266
Quote:
Originally Posted by Perfectlap
A Cayenne engine in a Boxster sounds interesting. A V8 Audi engine sounded interesting until I spoke to my Porsche Indy who could not have more bad things to say about their engines after I mentioned an interest in buying an R8 once the prices had come down.
Subi Boxer engine would be pretty bad ass. A guy in one of the many autocross clubs around here made some exhaust mods to his and it sounded like a .50 caliber cannon.
Cayenne V8 = Audi V8. It's the same thing.
kcpaz is offline   Reply With Quote
Old 08-09-2010, 12:57 PM   #15
Registered User
 
Join Date: Sep 2006
Location: Honolulu
Posts: 29
I wanna see this
BlitzSRM is offline   Reply With Quote
Old 08-09-2010, 04:46 PM   #16
Registered User
 
Join Date: Dec 2008
Location: Atlanta
Posts: 77
very interested in a build up with pix!
-Jimmy
jjanari is offline   Reply With Quote
Old 08-10-2010, 08:11 AM   #17
Registered User
 
Join Date: Jul 2010
Location: West Chester, PA
Posts: 211
Very interested as well. I own a 2008 Subaru Legacy GT, which has the exact same engine as the STi except with a different turbo (and obviously engine management).

The 2.5 liter Subaru engine is capable of safely putting down 350awhp without modification to any internals and with a mildly upgraded turbo , as long as it's got plenty of fuel and is running a solid tune. The only real soft-spots internally-speaking are the pistons & piston rings, which seem not to like detonation as much as perhaps some forged pistons would

In stock format, with an opened up exhaust and conservative tune, 280-300whp is easily accomplished with no other modifications.

At the same time, expect peak torque (of about 300+ lb/ft) to be delivered by 3000rpms and power to stay on until 5500-6000 rpms.

I think Porsche purists would miss the buttery smoothness of the flat six engine and how it never gets out of sorts, even at very low rpms in higher gears, but otherwise the engine is a great replacement if someone can make it work.

I'm not worried about the intercooler...plenty of ways to make that work....but I'm curious about the transmission adapter, starter mounting, and electronics.

Also, I think the boxster 5-speed's gearing is actually ideal for this engine. The taller gearing means the turbo will get a higher load, which means earlier spool while giving some nice long-pulling times. Combine that with the drop of ~300-400 pounds + 2 less wheels to drive, and I think the engine will drive like a dream.

Good luck to you. This is one swap that's been waiting to happen.
__________________
99 Boxster 5spd - 64k miles

06 Civic SI - 114k miles, D.D., unbelievably reliable and fun to beat on everyday.

08 Legacy GT 5spd - 74k miles.
JoeFromPA is offline   Reply With Quote
Old 08-11-2010, 08:48 PM   #18
pcw
Registered User
 
Join Date: Dec 2009
Location: CA
Posts: 26
Interesting discussion going on here. I have an 08 STI with a TBE and a stage 2 tune. It is putting down 340 HP to the wheels and 390tq. This is my second STI, started with an 06. I also just got a 2011 Spyder. The 2 cars are totally different, my STI is my DD and the Spyder spends most of the time in the garage covered. The STI is an in your face kinda car, it's ruff around the edges and just want to be driven hard all the time. It is the funniest cars I have ever driven, that is until the Spyder came along or along came the Spyder . The STI handles very well and I love to drive it when the roads are wet, it slides through corners with total control.. IMO the high roof line makes it a little top heavy and at limit driving does under steel some. The Spyder on the other hand is the cut above the STI in every category , the most neutral, balanced, smooth car I have ever driven and that includes a GT3/RS. The handling is almost like the car reads your mind, it's like you move your eyes and it's there. Putting and STI motor in a boxster would be cool, you might have some fit issues with the motor and as you mentioned the trans, but I think the idea is a good one. That would be one bada$$ car. Good luck with it if you decide to do it.

pcw

Last edited by pcw; 08-11-2010 at 08:58 PM.
pcw is offline   Reply With Quote
Old 08-11-2010, 09:53 PM   #19
Registered User
 
Join Date: Oct 2008
Location: Gilbert, AZ
Posts: 266
It's not a question of whether or not I'm going to do it. It's already started. I have a donor car already (a 2000 "S" with a blown motor) and I already have the first adapter plate finished. Here are the initial pictures of the project...

Last edited by Brucelee; 08-13-2010 at 03:58 AM.
kcpaz is offline   Reply With Quote
Old 08-12-2010, 02:58 AM   #20
JTP
Registered User
 
Join Date: Aug 2009
Location: MD
Posts: 628
Nice work! I didn't realize you were the guy that did the Subaru engine in a 911. I saw your site a few months ago and saw your videos on your exhaust also. Nice work on those as well. With a race prep shop at your disposal this conversion should move right along. Looking forward to see the progress.

JTP is offline   Reply With Quote
Post Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -8. The time now is 07:25 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page