About A Rabbit - 986 Forum - The Community for Porsche Boxster & Cayman Owners

evolvesociety · 07-15-2009, 05:01 PM

I am new to this forum, looking for some technical data about some of these boxer motors. I have a 1984 Volkswagen GTi, and am looking to make an engine upgrade. All naysayers please leave the thread now.

The plan with this car is rather extensive and quite over the top. I am looking to purchase a boxster totaled in a front end collision. Feel free to contact me if you have one. Anyway, I am looking for a 2.5 or 2.7L engine, preferably with 6 speed transmission included. My rabbit will be undergoing extensive body work and custom modification, and said engine will be mounted in the back of the coupe. The size of the two cars is rather similar, and I am looking to put everything into the rabbit. The transmission, engine, and all the rest of the bells and whistles.

I am looking for some specs on the size of the parts in the car.
How long is the engine?
How long in the engine + transmission together?
How wide is the engine, gearbox, and differential?
How far from the front of the engine to the rear axle?
How long from the shifter to the gearbox?

I am aware that I will need precise measurements to give the garage doing the body modifications, and will need to get them from the car that I use as a donor, but I am just looking for some clues as to the dimensions of the powerhouse. If anyone has any links to sites that may offer technical specs, please help me out!

And just a heads up, when this car is built it will be well worthy of the engine that goes into it. I am a VW AG fanatic. Thanks for the time!

chaabouni · 07-15-2009, 05:41 PM

That's quite a project. It's ambitious, but it sounds like you know what you're getting yourself into. Please do keep us updated, as I am sure many of us who are less adventurous would like to live vicariously through your experiences.

As for the parts, here are a few threads that may help you:

2.7L engine: FS: Complete 2.7L Boxster Engine
Parts Car: Porsche 986 Parts
Parts Car: FS: Parting 01 986 S Arctic Silver

Best of luck!

evolvesociety · 07-15-2009, 07:05 PM

Thanks for the info! The game plan for my car is...

I have stripped it. All that is left to remove are the engine and tranny, and former gas tank. It is going across the state to have a copious amount of body work done. I am having the rear of the cab from a VW caddy pickup installed to separate the cabin from the future engine bay. Also at this point a custom roll cage is being installed. I am currently looking for another donor car to perform a subframe swap into the front of my rabbit (for a donor I need a MK3/MK4 VW Jetta or Golf). These swaps are generally done only to accomodate a larger VR6 engine, but I will be using it, along with the roll cage, to strengthen the unibody car.

One of the reasons I need specs on engine/tranny sizes is because I need to have everything in the rear of the car custom fabricated to hold the 2.5/2.7L engine and gearbox. I need everything from the shifter to the exhaust manifold. The cars are extremely similar in size and this is not as crazy as it sounds.

The final product will be a mid engined, rear wheel drive, (hopefully) 6 speed MK1 GTI. I am building this out of disappoinment in the lack of boxer motors in the VW line. Also to show up some japanese metal (subaru STI).

Everyone give me some resources and I'll mention you when this thing makes it into PVW magazine!

GTI.jpg

RandallNeighbour · 07-15-2009, 07:45 PM

You should definitely upgrade the intermediate shaft on the motor before you install it, and use a cayenne rear main seal and say a prayer for both.

Flat 6 Innovations (sponsor at top right) sells the upgraded IMS. The dealer can sell you the Cayenne RMS that will fit.

Best of luck. I see lots of suspension and brake requirements with this size motor in that car to keep it right side up on the road or track.

evolvesociety · 07-15-2009, 09:09 PM

Quote:

Originally Posted by RandallNeighbour

You should definitely upgrade the intermediate shaft on the motor before you install it, and use a cayenne rear main seal and say a prayer for both.

Flat 6 Innovations (sponsor at top right) sells the upgraded IMS. The dealer can sell you the Cayenne RMS that will fit.

Best of luck. I see lots of suspension and brake requirements with this size motor in that car to keep it right side up on the road or track.

Thank you for the suggestion! Upon further investigation I found that to be great advice! I will be looking into tuning the engine as soon as I get set on which size/MY I'm going to use. But these catastrophic engine failures seem to be quite problematic in the earlier Boxster models.

As for keeping the car on the road, the center of gravity will be much lower than with VW's I4 mounted in the front, and the wheels will all be wider than they are now with much, much larger brakes. I am currently debating the best suspension system to put in the car. I will be keeping my non-powered steering, which should be fine as far as I can tell.

Keep the input coming!

PlayersExpress · 07-15-2009, 11:30 PM

You my friend are creative..

Personally, if I was spending this kind of money.. id just go out and pick up a 2001-03 996 Turbo, Ive found several from dealers for 30-35k with 40k odd miles on them..

Then upgrade the turbos, reflash, strip the back seats.. etc.. and theres your rocket

That is just me, I understand the reason for creativity and attachment to cars and projects, just like Im going to put about 20k into my 10k boxster in the next year.

Good luck and keep us updated. for specifics on engine size and such I would contact Jake Raby or even Brad Roberts on this forum. They have a wealth of knowledge between them.

cvhs18472 · 07-16-2009, 03:14 AM

I love people like you. I grew up as a street racer( big blocks ) and a sports car nut. ! built a 57 Ford with a 454 engine that I had to pull the engine to change plugs; a 64 MGB with a 289 which was a real monster. None of my projects were as ambitious as yours and I envy your dream. Keep up the work but think everything through before you start. You are going to make mistakes and have to regroup. Brain storming sessions with a couple of 6's always helps. Best of luck. Ed

Brucelee · 07-16-2009, 06:04 AM

I will be a naysayer, or at least wonder why you are not looking into a VW/Audi based engine upgrade. Why use a Boxer engine when you can likely find an easier, cheaper, and frankly better match within the VW group???

Just asking; its your money and time.

Topless · 07-16-2009, 06:39 AM

Hot rodding these motors is difficult and expensive. If you want a true "giant killer" go big. There is no substitute for displacement. A 3.8L should get it done at roughly the same dimensions as a 2.5L.

Brucelee · 07-16-2009, 07:03 AM

Quote:

Originally Posted by Topless

Hot rodding these motors is difficult and expensive. If you want a true "giant killer" go big. There is no substitute for displacement. A 3.8L should get it done at roughly the same dimensions as a 2.5L.

I would agree. If you are intent on doing this, go BIG!!!

On the other hand, Porsche had a 4 cylinder in the 969 that I think made upwards of 320HP at one point. Maybe that is an easier way to go.

evolvesociety · 07-16-2009, 07:04 AM

Quote:

Originally Posted by Brucelee

I will be a naysayer, or at least wonder why you are not looking into a VW/Audi based engine upgrade. Why use a Boxer engine when you can likely find an easier, cheaper, and frankly better match within the VW group???

Just asking; its your money and time.

Because VW and Audi do not make what I am looking for. While I do appreciate and love VW's torquey VR6 engines, I already have one in my other VW, and it would be quite a bit more difficult to source the proper components to connect said VR6 to a MR transmission. My problem with Audi's engines is that they make V6's, which I am way not interested in They just don't offer the power I'm looking for in the size I need. My passion lies in staggered, inline, and horizontally opposed 6's, and as I have no experience with the latter, I figured now's as good a time as any to get working on it!

I will be attempting to use all components from the Boxster as they are, or with minimal modification, and the rabbit is what will be modified to suit. The guys who are doing fabrication are extremely talented, and with the close sizes of the two cars I don't think it will be too terrible.

You, however, can naysay whatever you'd like boss.

Also, thanks for the support from everyone! I'll post some pics of it as soon as I have the old 2.0L I4 out of it (which was actually a swap to begin with).

Brucelee · 07-16-2009, 07:07 AM

The 968 was powered by an updated version of the 944's straight-4 engine, now displacing 3.0 L and producing 240 PS (236 hp/177 kW). Changes to the 968's powertrain also included the addition of Porsche's then-new VarioCam variable valve timing system, newly-optimized induction and exhaust systems, a dual-mass flywheel, and updated engine management electronics among other more minor revisions. The 968's engine was the second-largest 4-cylinder ever offered in a production car up to that time. A new 6-speed manual transmission replaced the 944's old 5-speed, and Porsche's dual-mode Tiptronic automatic became an available option. Both the Variocam timing system and Tiptronic transmission were very recent developments for Porsche. The Tiptronic transmission had debuted for the first time ever only 3 years prior to the debut of the 968, on the 1989 Type 964 911. The Variocam timing system was first introduced on the 968 and would later become a feature of the Type 993 air cooled six cylinder engine.

968 Turbo S

Porsche briefly produced a turbocharged 968 sold as "Turbo S", a fairly odd naming choice for Porsche which usually reserves the added "S" moniker for models that have been tuned for more power over a "lesser" counterpart, such as with the 911 Turbo which has infrequently been available in both "Turbo" and higher-performance "Turbo S" guise. Only 15 were produced in total and only for sale in mainland Europe. Tests conducted in 1993 produced a 0 to 60 miles-per-hour time of 4.7 seconds and a top speed of approximately 180 miles-per-hour, performance comparable to the much newer Type 996 911.
968 Turbo RS

A further stripped out version of the Turbo S which was built for Porsche's customer race teams between 1992 and 1994, this variant was available in two states of tune; a 337 bhp version which was built to the German ADAC GT specification and used the K27 turbocharger from the Turbo S, and an international spec version which used a KKK L41 turbocharger producing 350bhp and was reduced to 1212kg in weight (the ADAC GT version had to have ballast added to bring the car up to the 1350kg minimum weight limit allowed by ADAC regulations). Only 4 Turbo RS models were ever built, and along with the 964 Turbo RS these were the only Porsches to have been given the Turbo RS designation.

blue2000s · 07-16-2009, 07:50 AM

Why not buy the hardware before doing the fabrication? I'm sure there will be things that measurements will miss but you could catch by doing test fitting.

Kirk · 07-16-2009, 08:19 AM

#1 I've got to agree with some of the other posters about going bigger. The 3.6 and 3.8L engines have just about the same foot print as the 2.5 and 2.7L, but MUCH more power. This sounds like a very expensive project. I personally would go with a bigger engine to get the most bang for your buck.

Have you considered going air cooled instead of the newer water cooled engines? The last generation of air cooled engines are from the 993 and they were pretty powerful too, more so than the modern 2.5 and 2.7L. I'm just thinking that it might help to simplify things quite a bit to not have to worry about front mount radiators (although an oil cooler might be required). Older 911 engines are even simpler and would be an easier install. I'm not sure how much power the 901 and 915 transmissions from the MR Porsche 914 would take, but you can probably mate up a lot of the 911 engines to those transmissions for the MR layout.

Kirk

jderiansf · 07-16-2009, 10:02 PM

Quote:

Originally Posted by Kirk

#1 I've got to agree with some of the other posters about going bigger. The 3.6 and 3.8L engines have just about the same foot print as the 2.5 and 2.7L, but MUCH more power. This sounds like a very expensive project. I personally would go with a bigger engine to get the most bang for your buck.

Kirk

First of all, good luck w/ your project! Its sounds very cool. Kinda like a german SHOgun (you remember that one don't you? Its a Ford Festiva w/ a SHO Yamaha v6 mounted in back)

I believe Suncoast is having a sale on engines w/ no core needed. You could pick up one of these, get your boxster (w/ a blown engine or rms leak etc. ) and not have to find a crashed one. You could then sell off all the rest of the pieces or ???

Take lots of pics and document everything!!!

Lil bastard · 07-16-2009, 10:21 PM

Naysayers aside...

Dumb thread IMHO...

eightsandaces · 07-17-2009, 09:12 AM

Quote:

Originally Posted by Lil bastard

Naysayers aside...

Dumb thread IMHO...

I got your back on this one...

Perhaps the next project will be the infamous construction of a silk purse from the sow's ear...

Brucelee · 07-17-2009, 09:25 AM

http://968turbo.homestead.com/Number3.html

This was the "mystery car". I spoke to Gerd Schmid at the Porsche racing department and he told me the car was in England. I searched for two years and finally Gary Hill gave me a lead and sure enough, it was in England. The car is black with pink and purple blobs and is affectionately known as "Bubbles". It was purchased new in March of 1994 and raced in the 1994 BPR series, driven by Erik Hendriksen and Justin Bell.

The car is currently being maintained by Russell Lewis, owner of RSR Engineering (Porsche garage) and contributor to "911 & Porsche World" magazine. Russell tells me that the car has 7000 km on it and has never been crashed. Other reliable sources indicate that the car has had many "incidents" and blown engines. Another source once told me that the car was totalled and all that was left were parts, but we know this is not true. So maybe this car is still a bit of a mystery!

Russell says the car has all the endurance mods including 120 litre fuel tank, air jacks, leightweight parts and engine output increased to 440 bhp!

eightsandaces · 07-17-2009, 10:11 AM

If he wants neck snapping acceleration and money isn't an object why not convert to electric? At least after the substantial outlay the car would be inexpensive to operate... Love the RS engine, the specs are eye popping, however, I'd rather have said engine in the 968RS.

evolvesociety · 07-17-2009, 10:18 PM

Nice turnout.

I feel bad for those who are interested in such things as silk purses and sold out shelby!

Anyway, thanks for the feedback about the larger displacement engine. How close is the sizing on this? I know that VW's VR6 engines had the same size block in the 2.8 and 2.9L models, but how close can these larger ones be? Keep in mind that this car weighs pretty close to nothing and it does need to stay on the road, so I'm not looking for insane power. Before I decided on this flat 6 route I had almost purchased an old 928 with an 8 cylinder engine just to be unreasonable. Then I decided smaller is better.

Another thing I was worried about with the larger engines is, it needs to be MR and not RR to preserve handling, and I need to keep the engine in front of the rear axle but behind the firewall.

The most expensive part of this (sadly) is purchasing the Porsche parts for it. The body modifications and the installation of the motor should come out to be well less than the price of the engine and transmission. I am drawing up all the plans for the modifications to the frame on AutoCAD 2009, which should make things reasonably precise. I know I should buy the engine and tranny I need first so...

What engine do you feel I should use?