All Porsche powertrain in SLC?

Getting close, thanks for asking:
1) Physical wiring of engine: Done except for dash. So far, out of the 120+ connections I made, my extensive design work in Excel paid off and the harness was exactly correct except for the throttle body which was reversed (an easy 1-minute fix). The dash is easy since it's just power + CAN and the wires are already run to the dash. It will be a Motec D175. Beyond that, I'm just fixing a few minor things like getting a couple switches to properly work. The rear wheel speed sensors don't seem to be compatible with the ECU either, but all this doesn't prevent an engine start.
2) ECU config: Done to get the car started except for things like traction control since the speed sensors aren't cooperating yet. I'll need to fully calibrate a few more stock temperature sensor values, but they're close enough to run the engine initially. I also did the math to get the injector flow rates to a good enough spot. It's complicated because injectors don't follow the theoretical flow rates as their input pressure in the fuel rail varies. You always know the the 3 bar rate from the manufacturer (453 cc/min in my case), but for stock injectors it's hard to find their calibration values. All injectors have some variance off the theoretical rate as pressure changes. I may need to send one in to be tested later to get exact values.
3) Sent the ECU back to AEM today for a little rework since there were a few board changes. I have a relatively early AEM Infinity, so that's why.
4) Converting the rear transmission mount from aluminum to steel for piece of mind. Getting part back next week.
5) Seats: bit the bullet and got Tillett B4's. Love 'em. IMO, they are the best option if you want to make sure a 6' 2" passenger has their head fully inside the roll bar.
6) Alignment: getting a basic alignment done in my garage.
7) ISIS wiring: need to finish up headlight and front harness install. No biggie.
8) Fender liner install: postponed except the rear ones on the center section, which is done.
9) Windshield: waiting until last minute to install
10) Seat belts: waiting, but think I found a good cheap supplier at SEMA. I'm doing a 5-pt harness and am still working through the legal issues of getting CHP approval or if it doesn't matter.
11) Interior: what's that? Punting on it until after car is on the road.
12) Headers: Fully custom. This was a TON of work, but really interesting. I managed to find the right flanges from SPD Exhaust and then bought the pieces to build my own headers and exhaust. The fitment is very tight, so accuracy is key. The angles are all very complicated, since most of the time they go in 2 directions. I just tack welded them and then had them professionally finished. After that, ceramic coating.

That's the top-of-my-head list. I'm sure there's more. I'll probably wait until the new year to start the car, but it's basically all there ready to go. If I took a week off work, I'd have a running car. :)

Tim
 
Getting close, thanks for asking:
1)
10) Seat belts: waiting, but think I found a good cheap supplier at SEMA. I'm doing a 5-pt harness and am still working through the legal issues of getting CHP approval or if it doesn't matter.
11) Interior: what's that? Punting on it until after car is on the road.

Tim
Hi Tim,

2 FYIs

CHP doesn't care about the seatbelts during the registration process. Its not what they're looking at. They just care that all your components aren't stolen. However, I'm not aware of any 5-point harness that is road legal. Its all about the latching mechanism.

Doing the interior is much easier without the windshield installed.

Cheers,

Ruth
 
Hi Ruth,

Interesting, so then who cares about he seat belts? Is it an issue if you get pull over? Is there some other inspection?

My understanding is that the Schroth Profi II ASM FE harness is road legal because it's got the push button release.

I'm still trying to get more details about the road legality aspects and who ultimately regulates the seat belts. In talking to a seat belt manufacturer at SEMA, they said it's actually not the DOT, but another agency whose name I now forget. If anyone has links to where the seat belt laws pertaining to the type of device (vs. need to wear one) are documented, I'd love to see it.

Windshield - completely agree. That's why it's last. Also something that I'd rather not scratch by doing something dumb.

Best,

Tim
 
Hi Ruth,

Interesting, so then who cares about he seat belts? Is it an issue if you get pull over? Is there some other inspection?

My understanding is that the Schroth Profi II ASM FE harness is road legal because it's got the push button release.
If you get pulled over, urban legend has it that it could be a violation, but I doubt any officer will pay attention and I've read the California motor vehicle code and couldn't find any mention of any requirement other than needing a lap belt and in certain cases a shoulder belt.

You are correct though, the Profi II ASM is road legal based on the spec referenced in the urban legend. Forgot about that one.

FWIW, you WILL get pulled over. We've been pulled over 4 times since July. We didn't have the plates on the car yet but were clearly displaying the temp permit. Officers just like to look at it.

Get the belts you like and don't worry about it. We're more concerned about what to do about a front license plate.
 
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I've taken two cars to the CHP (part of the SB100 process), they've never ever even looked inside the cars. They just want to make sure that none of the major components are stolen.

Been pulled over in my cobra with 6-point harness, didn't hear a word about my seatbelt. I know lots of people running 5-6 point restrains on the street, I'm sure some of them have been pulled over :), but I've never heard of anyone having been hassled about anything other than not wearing them.

I'm sure you'll be fine.
 
I had 5 point racing harnesses in my SLR and was pulled over multiple times (never for any infractions, they were just curious). Anyways, I never heard anything from the LEOs about my "racing" seat belts. I wouldn't worry about it
 
Thanks for the update Tim. Love to see some photos if you get a chance, particularly the engine/headers. Sounds cool.
 
Funny thing you ask. The plan is to fire it up this weekend. I still need a firmware update for the ECU and a base map, but otherwise it's ready to fire up and see if it will idle. Seat harnesses went in this past weekend (mostly, waiting for correct crotch straps), so I'll have some protection if the car turns into a soapbox down my street. :shy:

Tim
 

Attachments

Cool! Would love to see pics/video if you are able.

Is it blue, or is that just painter's tape? (I recall it being white gelcoat)
 
He updated his build site fairly recently
SuperLite Coupe | Ze German does a bloggings!
Luke - thanks for asking.

Matt - thanks for putting the link in.

I've been a bit distracted with new work opportunities, but I've been slowly rebuilding the engine. Turns out the issue was a coolant/air vent configuration issue that I'd screwed up and the engine actually wasn't fundamentally broken in any way. Compression was fine, no gasket issues, etc. Just some wear and tear.0

So I took it down main case (without splitting it) to replace the rod bearings. Now I'm awaiting arrival of new rod bolts, which isn't as simple as "call ARP for a set" in the Porsche world. It's more complicated and MUCH more expensive. I also sent out the heads to be rebuilt and should have those Friday or Monday. I've done a lot of parts washing wherever I can and am replacing all the seals and o-rings I come across. I'm basically getting a fresh engine as a result and have learned more than I want to know about GT3 engines. :)

For a much longer read, see this thread on Rennlist: 996 GT3 engine rebuild - Rennlist Discussion Forums. It's been really helpful to get advice from Porsche guys there.

The main case looks like this FYI:
 
Had to service my GT2 this spring. They are wonderful machines, but any car that for a plug change starts by remove tail lights, bumper and rear wheels first is not going to be fun. I was amazed by the cost variance between vendors and even found some of the parts on Amazon as Bosch parts like MAP and MAF sensors. I've never felt the need to up pay for the Porsche part # if same part available through manufactor.

Thanks for update, sorry for your frustration and hassles. Hey, it'll be like a NEW GT3 engine now. Plus how many guys can say they've built a GT3 engine!

How do you think serviceability will be in this application? I doubt it could be much more difficult than OEM. It was obvious to me that the 996 wasn't intended for this engine compared to working on my 964's engine.
 
Had to service my GT2 this spring. They are wonderful machines, but any car that for a plug change starts by remove tail lights, bumper and rear wheels first is not going to be fun. I was amazed by the cost variance between vendors and even found some of the parts on Amazon as Bosch parts like MAP and MAF sensors. I've never felt the need to up pay for the Porsche part # if same part available through manufactor.

Thanks for update, sorry for your frustration and hassles. Hey, it'll be like a NEW GT3 engine now. Plus how many guys can say they've built a GT3 engine!

How do you think serviceability will be in this application? I doubt it could be much more difficult than OEM. It was obvious to me that the 996 wasn't intended for this engine compared to working on my 964's engine.
No need to feel sorry! I've actually not had any big points of frustration. Hassle, sure that's the case from time to time, but for me this has all been a giant learning experience. I love learning by doing and don't mind digging around to find that little crucial piece of info, so it's all good. And like you said, it's kinda neat to be one of the few guys that have rebuilt a GT3 engine on their own.

The engine is pretty serviceable in the SLC. I pulled the plugs a number of times while trying to debug why I had no spark. I get scrapes on the arms, but I don't have to undo anything really to pull them. The only thing that's hard to get to is the belt and anything on the front of the engine, but even to change the belt on any 911 of I believe any era, you have to remove the front engine carrier. That's not super hard and not a frequent repair anyway.

Once you take the engine apart, you really notice how it's an air-cooled block with parts bolted to it to make it water-cooled via the heads and cylinder jackets. Moreover, the basic block is very very similar to a 930 block. It's basically a really old engine that's had new stuff added to it and still runs in the current Cup/RS/RSR cars. And it makes a reliable ~115 HP / liter.

Regarding parts purchases, I definitely haven't been going via the dealer. I'm friends with a local mechanic that can source many parts for less than the dealer price and I actually bought the rod bearings on Amazon (original Porsche part). Those you're really supposed to go with the original even though it's possible to source direct, because Porsche does a secondary quality control apparently and stamps their logo on it. But yes, I totally agree with sourcing from the supplier wherever possible through whatever channel is cheapest.

Especially the Bosch stuff tends to be fairly standard, but I've come across a few parts that have the supplier's name stamped on them, yet it's a Porsche-owned design so they won't sell it direct - ever. Those are the ones that really get you, like $98 rod bolts. Each, not for the set of 12. Ouch. Thankfully, I found them much cheaper through the wonder of Google. Research, research, research. :)

Jealous of your GT2, what a car!

Tim
 
I've used AutohausAZ for parts for our Mercedes. They seem to have the best pricing on parts for German cars, and they list the manufacturer of the parts so you don't have to guess if you're getting a cheap chinese copy, though sometimes they offer those and I've put 100k on a pair of front axles/cv joints which is about what we got out of the factory units.

Just found a fairly clean 944 w/ a blown head gasket on Craigslist and might have to delay my RCR 70 plans for a 944 LS3 :D
 
OK, so I'm guessing you had the bellhousing modified (welded?) to flip the bolt pattern on gt3 transaxle, correct?

What other modifications did you make (internal oil lines)? I also heard you can simply fill the transaxle with more oil to reach pickup when upside down? I was leaning towards the Graz, but with the engine combo that's coming together gearing is a little short 1-3.
 
OK, so I'm guessing you had the bellhousing modified (welded?) to flip the bolt pattern on gt3 transaxle, correct?

What other modifications did you make (internal oil lines)? I also heard you can simply fill the transaxle with more oil to reach pickup when upside down? I was leaning towards the Graz, but with the engine combo that's coming together gearing is a little short 1-3.
Yes, the bell housing had to be modified since the bolt spacing is slightly different. Weld and re-drill.

Other than that, the standard modifications such as a new oil drain plug were done by Gbox, including removing of the oil cooler. It just plumbs feed direct to return and should it ever be an issue, it's just AN fitting that I can then run through a Sadev. Call them for the details on filling with fluid - I've since forgotten how much after I filled him. Very helpful team over there.

Tim
 
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