Dumb ques: If I got a turbocharger from a 930 could I bolt on to a regular 911?

[Paul-V.]

Yes, yes, this may be a very very dumb question to those of you who 'know better', but I'm kind of curious. I know of some factory KKK turbochargers from 930's for sale. One guy says it is bolt on. Would I be able to bolt on a turbocharger into a regular 911, or would there be drastic problems. Thanks.

[dtw]

Paul - it is not a dumb question but unforunately it is also not a bolt-on. Just a turbo alone will not do much for you; there are bolt-on kits available for NA 911s from Supercharging of Knoxville (supercharger actually, not an exhaust-driven turbo), Protomotive, Powerhaus, others.

[Kurt B]

Trust me, I've thought about this a lot. I know with a DME system is going to be a no go. The 930s from 84 to 89 still used that ancient CIS lamer...dunno why tho.

[WydRyd]

It would probably be a bolt-on for another 930, but certainly not a naturally aspirated 911.

You need to have appropriate exhaust & intake plumbing fabricated in order to facilitate the turbocharger.

It's not a small job, but certainly worth it in the end if done right

[speeder]

There are no dumb questions around here, Paul. Just a lot of dumb answers.

A turbo could be, (and has been), fitted to a 'regular' 911, main problem is that boost is quite limited by compression ratio of N.A. motor. Basically, the lower the C.R., the more boost you can run, but on a N.A. car, the higher the C.R., the more specific output. There are some brilliant engineers and hotrodders on this BBS, maybe someone can explain in better detail. Welcome aboard!

[speeder]

BTW, I started typing above post before any of the others appeared, these are not dumb answers. And I was kidding, of course, welcome to the board!

[A Quiet Boom]

Based soley on used prices for turbo motors as well as the fact that the turbo long block itself differs from a standard 911 motor, I think you'd be farther ahead both from a HP as well as financial standpoint to just sell your current motor and install a factory turbo motor, modded or stock. I have researched this and this is the route I'll be taking on my next project sometime next summer.

[Paul-V.]

Thanks for the info and advice guys. Let me say that the people on this forum are really great...I would have expected to have been flamed by now for asking alot of rather silly questions. Just to let you know, I know very little about 911's (hence why I am asking alot of 'beginner questions'). I just got one about 3 weeks ago and am now in love. My brother is the one who has been lusting after a Porsche 911 for the past 16 years (and I am the one who bought one before him--though he's got a 912 and a 928!) Really never thought I'd own one because, let's face it, the price of even a beat up 911 is relatively high, but I managed to find a good deal on it. You'll probably be seeing more 'dumb questions' from me in the future (so I'll apologize in advance). Thanks for the help.

[A Quiet Boom]

The only dumb question is the one you were afraid to ask. Knowledge is built by asking questions as well as answering them so ask away!

[5axis]

I have been following Rarlyl8's conversion and he is eventually going to have a great car. Given the headaches and expense I would bet he would agree that if you want a turbo, then buy one. You can do the swap thing, but you are still short all the expensive turbo brake and suspension parts. The engine is only the begining of a full turbo conversion. Something to ponder before diving in.
david 89 turbo cab

[Overpaid Slacker]

I think it's a brave question, and the stuff that innovation is made of. However, I think speeder mentions one of the most basic of issues -- design theory behind the compression ratio of the motor itself. Turbocharged motors traditionally run at a much lower compression (7.0:1 vs 11.5:1, e.g.) than n/a motors b/c when you add boost to "normal" compression, things can go catastrophically wrong very very quickly.
Basically, think of a turbocharged system like a feedback loop --
Exhaust drives the turbo, which compresses the intake charge, resulting in more power, which results in more and more "forceful" exhaust, which further increases the intake charge, which results in even more power, which results in even stronger exhaust, causing even higher compression...

Although, if you bolted a turbocharger on the hood, it might keep the deer away...

JP

[stuartj]

David
I find it very hard to read your posts. I want to, but after 5 minutes of trying, I cant get past that captivating animation. Its...hypnotic.

stuart 87 Carrera

[WydRyd]

Originally posted by Overpaid Slacker
when you add boost to "normal" compression, things can go catastrophically wrong very very quickly.

JP, I run 0.7bar at 9.5:1 C/R and nothing catastrophic has happened to my engine over the last 5-6 months. Nor Mike's or Juan's over 2 years

You have to look at the WHOLE package, not just say high compression + boost = catastrophy

You have to factor in ignition timing, engine management, intercooler efficiency, fuel system flow capacity & fuel quality, limited boost levels, effective C/R etc... With a "properly" tuned/designed system, things don't just go BANG! If they did, how does Porsche get away with running the boost levels (0.8bar) they do on such high C/R as 9.4:1 C/R?

[Wayne 962]

It's kind of similar to buying a second sink for your bathroom. Yes, the sink can bolt in, but you have to modify a tremendous amount of plumbing and piping (not to mention tearing out your cabinet) to make it work...

-Wayne

[WydRyd]

Nice analogy Wayne

However, in the end, it comes down to how much you love your house and how bad you actually want that sink in there, not to mention how much you're willing to spend to make it fit

There's no use buying a new house just because it's bathroom has a second sink.

Paul-V, are you asking the question because you are seriously considering a turbocharger conversion, or just curiosity sake?

What type of 911 do you have anyway?

[juan ruiz]

I have some REAL NICE Turbo KITS 4 Sale, If you wish send me a e-mail to JRuiz12599@aol.com and I will send you all the Inf.
I be back home on monday,so as soon as I arrive I can send it.

Regards Juan
Turbo 3.2 Undercover Undersurgery

[Overpaid Slacker]

Wyd-

Admittedly an oversimplification, but just to illustrate that there are some fundamental design differences when you start designing a turbocharged motor from a clean sheet, so to speak. And w/o anticipating and accommodating all of the variables you mention (which goes beyond "bolt-in" in my world of limited mechanical acumen), things could go spectacularly wrong just amping the compression of an already 11.0/11.5:1 motor.


9.5:1 is a relatively low c/r for a performance n/a motor (of recent vintage), but as it's higher than "stock" turbo motors (which have always been in the 7.0/7.5:1 area if memory serves), it makes sense that you're at .7 bar, which is relatively modest boost. Porsche can do anything within the realm of materials science that it puts its mind to, but again, we've left bolt-in land.

Best,
JP

[clnilsen]

Does anyone have a web address for superchargers of knoxville, or any other Turbo bolt on manufacturers?

Thanks!

Chuck

[barlowdo]

Merv,

I am interested in how much noticable gain you get from your .7 boost ? I have also thought along these lines of cutting back on the boost on a NA engine. Of course you would not gain all the benifits of full boost on a factory Turbo boost engine but I would guess you would gain some.

-Don

[island911]

Originally posted by speeder
. . .A turbo could be, (and has been), fitted to a 'regular' 911, main problem is that boost is quite limited by compression ratio of N.A. motor. Basically, the lower the C.R., the more boost you can run, but on a N.A. car, the higher the C.R., the more specific output. . . .

to add a bit to this; your motor pulls in air and compresses it (just as a turbo does) When air is compressed, it heats up. Too much heat/compression and the air fuel charge goes bang, on its own, and too soon. (detonation)
Your N/A engine has been designed to depend on the piston to compress the air/fuel just enough to keep this from happening. So if you add the boost of the turbo you will need to run expensive (higher octane rated) gas, or else detonation will occur.
The big pay-off for turbos comes from letting the piston do less work compressing, and letting the turbo do that work instead. AND- you then have the opportunity to cool the compressed air (intercooler) before it gets fired-off. (read: a cool dense charge of fuel and air in the cylinder to make lots'o power)
--in a nutshell--