Boxster V8 project log

[redpepperracing]

Yes, I have the same image saved. Mine is mounted up at the same level as the brake master, not a lot of room above it, if any, to do something similar.

[Marc_986]

Today I filled my cooling system again after replacing the waterpump yesterday. Went much better this time having probably most of the coolant still in the radiators etc. (previous time, everything was empty). I think I got about as much back in as ran out yesterday. Might have spilled a bit, but should be close. I did a combination of vacuum for getting initial air out (still quite effective) and pressure (pushing the air to places where it can escape). Now when I pressurize to 1 bar, the fluid gets pushed down to about half the reservoir, so not that much air left anymore.

Put the longer belt on (I suspect the short-ish belt might have made the waterpump die) which does fit better. Still have a bit left on the tensioner. So updated belt length for engines with AC (or at least the compressor in place as I have now), but without PS pump is 6PK2080. I guess a 2100 might still work, but this one works well, better than the 6PK2065 I had on it before.

[Marc_986]

No more drops visible Took the car out for a little ride Friday evening and for the first time in the three years of ownership I could drive it more relaxed. Still keeping an eye on the gauges and listening for odd sounds, but it was so much more pleasant. Finally confidence in this car is growing and I might actually start to enjoy it! Well, I always enjoy working on the car, but enjoying a ride is a good bonus

[redpepperracing]

That's awesome! I know the feeling of doing all that work and then being able to just enjoy it. I did my first track day in 3 years a couple of weeks ago and it was great to just be able to drive and not really worry about anything. Many more days of that ahead!

[Gilles]

Originally Posted by Marc_986

No more drops visible Took the car out for a little ride Friday evening and for the first time in the three years of ownership I could drive it more relaxed. Still keeping an eye on the gauges and listening for odd sounds, but it was so much more pleasant. Finally confidence in this car is growing and I might actually start to enjoy it! Well, I always enjoy working on the car, but enjoying a ride is a good bonus

Awesome! It is a great feeling everytime you drive your car after doing a succesful repair, congratulations!
.

[Marc_986]

Thanks! Next step are the old (rear) and crappy (front) tires. Set of Michelin PS4 will hopefully arrive next week to be mounted. Will also get the front end alignment checked (although it drives fine the way I have it set now, maybe just to see how wrong my own attempt was ;-))

Small stuff today, but also some time to start looking at the bigger picture again, the engine. As you'll know, the idea is to but the Audi BBK engine in (originally in the Euro S4). So far it seems that I do need to make some chassis / suspension mods to get it to fit. Should be able to get it through the inspection and be able to drive it legally on the street.

Still, as a side activity and coming from my curiosity I'm trying to get a view on what Porsche would have to offer to this Boxster. I'd be looking at similar power as the BBK and this is what I have learned so far;

New parts (block / rotating assembly) are available in M96.03 form and the money for that is not outrageous. Would still need the rest of a (broken) M96.03 or similar to build it up to a full 3.6 engine, but it would be as new without the main concerns of the M96/97 family (being new, but surely it will still have the engineering issues in...).

This seems a cheaper route than getting a full M96 996 engine (whichever displacement) which in general seem to run at $20k or close.

Surely in these engine families you'd want the GT3 engine. Turns out that his is not family at all (despite the M96 designation) and is a 'Mezger' unit. Basically very robust and capable. Full engines very expensive. In comes the 996 Turbo engine which is the same block, but different parts for the different application. Many more turbos build than GT3, so availability is better. Can find a full engine (all parts on) for $10k on these turbos, which is less than normal 996 engines. Strange.

So, I'm not a turbo fan. Making great power, broad torque curve, but lacking character because of that. Turning a 996 turbo engine into a NA might be a bit of work though, need to know more about the differences (so far I know of conrod and heads).

Another downside of these GT3 and turbo engines are the different bolt patterns for the transmission. Would need to see whether a G87.40 unit (the ones behind the MA1 engines in the gen2 987 S) would fit.

Then finally there is the MA1 engine which is the DFI engine in later 987 models and the 981 (991 etc). So far this one appears cheaper to find than the M96 / M97 engines and is by design a far better engine. DFI though...

Anyway, just writing down my mental notes ;-) Input is always welcome

[The Radium King]

this one comes with a transmission ...

https://tuningbynick.com/pages/boxster-k-swap

[Marc_986]

Not really looking for a 4cyl. Don't get me wrong, these are little marvels of engines, but not something I would consider for the Boxster. It'll be either the V8 (still most likely as I have all the expensive stuff already) or an upgraded Porsche engine. Both have pros and cons, just trying to straighten my head out.

[redpepperracing]

Originally Posted by The Radium King

this one comes with a transmission ...

https://tuningbynick.com/pages/boxster-k-swap

That's my guy! My buddy works with Nick, and if you look at the track picture in my project thread, the silver Boxster is his test mule K swap, and the silver 997 beside it is Nick's turboed 500+ HP K24 daily driver. Nick is not in the picture but he is there somewhere.

[Marc_986]

Just a short update. Not much happend since the last update, but new tires are now fitted. Went with Michelin Pilot Sport 4. In general regarded as a good tire for this car and being a quality brand it will easily improve over the old and low quality rubber it had before. Alignment also done. Toe was off a fair bit, but as I experienced, total toe was actually good enough to drive straight without too much pulling etc. Camber was also off by a bit on one side. Both sides (front) now at -1deg. The rear was also a bit off now, maybe due to new tires fitted. This was corrected as well.

Went on a longer trip on a warm day and ended up in rush hour in the city heading back home. Good thermal test for the car as it was nice up to operating temperature when I entered the city. All good, temps around 90C seems good to me. Checked under the car while it was being aligned, no new leaks or issues spotted.

So I signed up for a local tour sometime end of September. Just a 60mile tour in the area with 20 cars max. Nice opportunity to take the car out, enjoy nice roads and meet some local porsche people along the way.

On V8 side I decided to cut a small part of the chassis out of the wreck. This is the part / bar between engine cover and access panel. This means little cutting, easy to fix, but giving all the possible clearance I could need on the front side. Idea is to move the engine as much forward as allowed by the driveshafts (before they hit the U-shaped suspension carriers). In that position I'll try to fit the engine cover....

This action is planned for this weekend / next week.

[Marc_986]

So, time for a fitment update. As I mentioned, angle grinder time to remove a piece of sheet metal from my wreck. This really helps engine positioning, happy I cut it out

The idea was to move the engine / transmission as much forward as possible to gain clearance at the rear. Main limit is the driveshaft clearance to the suspension support U-shaped things. This is about as far as I could go:


Might be difficult to see on the picture, but height is about right and I think all moved forward by about an inch or so (will measure later). For the driveshaft it comes close, the thicker ones I will actually use might be really tight...



With that done, still a lot of clearance at the front. You can see the standard engine mount with enough clearance to the engine:



The heads will need some extra space at the top part where the bulkhead angles to the rear. Not an issue now that it is cut out, but something to keep in mind.

The cayman engine cover almost fits. On the left side it fits, on the right it fouls the crankcase ventilation elbow on the cam cover (which I was expecting and probably needs to be repositioned).



Again, difficult to see due to angle and light, but you should be able to see the breather elbow..

[Marc_986]

Moving on with more pictures. The heads themselves clear the cover fine, enough margin at the top, no issues here:



And as a final step for now I have put the intake manifold back on. This does give a height issue as it will not allow the cayman cover to fit at the rear (cover angles down), not at the front. Overall it is just too high.

Not mentioned before, but the engine height chosen for this fitment was with the sump in line with the bottom of the car. I don't want to drop it as it seems a bad idea to have the sump as lowest part of the car...

Picture with manifold:


So to summarize this test, I think the two main concerns are:
- Breather connection on valve cover. It is also the head most rearward and moving the engine further to the front would be good.
- Intake manifold is just too tall.

The transmission can't move further forward due to driveshaft clearance. I currently have the 5.5mm spacer between engine and transmission which is what should fit regular S4 / RS4 flywheel / clutch combinations. There is also a 11mm spacer which is used on the V6 engines.... every bit could help here.

Manifold... hmmm.... the only alternative I have seen is the RS5 intake manifold. This is a simple (and cheap) plastic piece. As the RS5 is DFI it doesn't have injector holes, but the RS5 came with 'swirl flaps' in a separate part between head and manifold. In theory I could make a similar part without those stupid flaps but with injector holes. Height of that manifold is unknown to me, it seems to have a slope on it (lower at the front, higher at the rear), but not sure how it compares against the S4 one...