Anybody here turbo a non-turbo 911?

[kwiktsi]

Has anyone here turboed a non-turbo 3.4 996? I am thinking of fabbing up a single turbo setup for the car, it will be extremely easy, but just curious how the motor holds up to boost. I can't find the compression ratio anywhere for this car, maybe I'm not looking in the right places, I dunno. I was thinking I should be able to get away with ~7psi or so fairly easily on the stock motor- as long as the motors are relatively strong. It would not be my first NA to turbo conversion by a long shot, but I am not familiar with the Porsche motor and tuning to know what hurdles lie ahead. Thanks in advance.

Joe

[Loren]

A 996 Carrera and a 996 TT use different base engines.

[kwiktsi]

A 996 Carrera and a 996 TT use different base engines.

Thanks, I'm aware of that. That's why I am wondering what the compression ratio of the NA motor is and if anyone has had any luck adding a turbo to one. I have seen a few with superchargers, so I know they'll handle some boost. I just need specs and want to know if anyone has done it here to know what to look out for when boosting this motor. Thank again though.

Joe

[viper501]

I think Ruf has done it, although I'm not sure what they have done to the internals. IIRC, compression on the 3.4 is something like 11:1 so I don't think you want too much boost going into the engine and tuning better be spot on. I'd suggest you keep the Goat for high HP and enjoy the 996 as is. Replacing that engine is not what I would call cheap. BTDT.

[kwiktsi]

I think Ruf has done it, although I'm not sure what they have done to the internals. IIRC, compression on the 3.4 is something like 11:1 so I don't think you want too much boost going into the engine and tuning better be spot on. I'd suggest you keep the Goat for high HP and enjoy the 996 as is. Replacing that engine is not what I would call cheap. BTDT.

I just like modding things, I always have. But you're right- one screw up and it's done. The GTO is~11:1 stock also and I have run up to 14 psi on a stock motor, but tuning with that car is easy with all the tuning software available for the LSx motors. I didn't know if there was anything similar to HP Tuners (www.hptuners.com if you are interested at all) for the Porsche or not. Or if there is something known about them like "the case flexes too much on the NA motors with boost" or "the heads tend to lift under boost and blow gaskets"- something common that I just haven't been around long enough to know (all cars have their own issues when modding). It just seems that a majority of Porsche owners just leave it alone or have one of the few shops do it for them, so the knowledge isn't as public as it is with other cars apparently :(. Oh well. Thanks guys!

Joe

[viper501]

Joe,

Majority of the problem is that the engines are so blooming expensive and there really aren't that many of them relative to the SBC's. Therefore, the learning curve can be fairly expensive. I think there is someone on Rennlist, or maybe 6speed, doing his own centrifigal s/c build.

Ruf did this ... http://euroautoforums.com/forums/index.php?showtopic=1408 ... while it looks like a 997, the interior shows it is really a 996. The back end also shows that it has twin turbos with the IC's old school style on top of the engine.

Also, the turbo cars (TT and GT2) and the GT3 use a substantially different block than the m96 that is installed in the 996/97 cars. It is much stouter and is really more a water cooled version of the 993 engines. Presumably, this is because the m96 can't take the boost levels that the TT/GT engines can handle.

[kwiktsi]

Joe,

Majority of the problem is that the engines are so blooming expensive and there really aren't that many of them relative to the SBC's. Therefore, the learning curve can be fairly expensive. I think there is someone on Rennlist, or maybe 6speed, doing his own centrifigal s/c build.

Ruf did this ... http://euroautoforums.com/forums/index.php?showtopic=1408 ... while it looks like a 997, the interior shows it is really a 996. The back end also shows that it has twin turbos with the IC's old school style on top of the engine.

Also, the turbo cars (TT and GT2) and the GT3 use a substantially different block than the m96 that is installed in the 996/97 cars. It is much stouter and is really more a water cooled version of the 993 engines. Presumably, this is because the m96 can't take the boost levels that the TT/GT engines can handle.

Wow, that car is a work of art. Thanks for the info, I'm still not sure if I want to bother trying or not. This car is new to me, so I'm not too familiar with the ins and outs yet and don' know of any message boards aside from this one- it's going to be a learning experience for me if I do anything with it, that's for sure.

Before I do anything, the car has some other minor issues that need to be worked out and some paint work done. I bought it from a used car lot for a steal of a price, but you can tell it's been around the block a few times. It's going to take some work to get it where I want it prior to even starting any mods. It is one of those "looks great from 5' away" cars. It isn't in too bad of shape, just has had some shoddy paint work done in the past and my winter project is more than likely going to consist of disassembling the car, stripping it, doing whatever body work is necessary and respraying it. Still undecided if I am staying with the silver or doing something custom since it isn't going to be original anymore anyway. Decisions, decisions....

Joe

[viper501]

Keep us posted on your progress. There is a lot of information here but you can also look at rennlist.com and 6speedonline.com . Rennlist tends to be a bit more tech than 6speed but neither seem to have as much tech information as here.

[kwiktsi]

Keep us posted on your progress. There is a lot of information here but you can also look at rennlist.com and 6speedonline.com . Rennlist tends to be a bit more tech than 6speed but neither seem to have as much tech information as here.

I am amazed at the amount of info on this board! Everything you need to own and maintain this thing :). I just wish there were more serious modders for me to learn from without breaking stuff myself ;).

Anyway, I will certainly keep you guys posted about whatever I do. As of right this second, I really have a sour taste about modding it- just got my GTO back together yesterday, took it out last night and on the way home, my $1400 twin disk clutch with 3000 miles on it started slipping in 4th- I'm furious. Right now, I don't want to mod anything, just drive the thing and enjoy it lol.

Joe