Converting a 911 SC to a Turbo

[Sauriel]

Hello everyone.

I have recently pondered about some ideas about doing something mildly interesting with my 79 SC.
It has a newly rebuild with all the low-hanging fruit, SSIs, 964 cams pistons etc , but its still CIS.
Pricing up a full twin plug EFI Motec rebuild quickly became 20-25 grand.

So I got thinking, ok its no doubt gonna be wonderful... but its still 25 grand for essentially 40 bhp.

So how about perhaps converting it into a narrowbody yellowbird-inspired car instead? I wont do a thing about the aesthetics, its a non-sunroof SC with Recaro buckets, halfcage and lightened to about 1050 kiloes. Would be cool with a sleeper I think?



But how about building a turbo engine? Im thinking Motec M84 930-style turbo with perhaps 450-500 bhp? Obviously I would need a 930 gearbox as well, as well as uprating the brakes and suspension etc....

Should I build it on my SC engine, or am I better off selling the engine and buying someone elses engine?

But realisticially, how much is this going to cost? And who should do the job?

Im thinking Richard Chamberlain of CTR developments? www.ctrdevelopments.com

Axel

Edited by Sauriel on Sunday 26th July 15:03

[g7jhp]

Maybe a 3.6 engine transplant from a 964/993 with a supercharger. Some one has done it here

You'd probably be better off buying a 996 turbo for outright speed and keeping your SC as is (sorry that's the sensible, but cop out answer)!

Edited by g7jhp on Sunday 26th July 15:27

[Sauriel]

I have a Cayman R with around 385 bhp for sheer speed, thats not why Im doing this.

and I prefer turbos to superchargers , much more effective!

[Jevvy]

g7jhp said:

Maybe a 3.6 engine transplant from a 964/993 with a supercharger. Some one has done it here

How about a 3.6 without boost? You will be close to 300bhp which is more than enough to make a narrow body car fairly quick:

https://www.youtube.com/watch?v=Cmoy-oKS_KY

You could always bolt some boost on afterwards if you want more power but boosting any NA engine is never cheap and often turns into a long painful project.

[Sauriel]

Ok, so it would be definately be better to basically sell my engine - and get a 930 or 965 engine?

[Jevvy]

Sauriel said:

Ok, so it would be definately be better to basically sell my engine - and get a 930 or 965 engine?

If your engine has just been rebuilt it will sell for good money, if you wanted a decent hike in bhp from boosting yr own engine you would have to tear it open again to change the compression ratio along with a few other bits.

Buying a 930 or 965 engine is an option but they are still old tech (CIS) and need swapping to efi to get much above 375 bhp so you are back to where you started cost wise (CIS to EFI)

An NA 964 or 993 3.6 gets you to 300 bhp and will do it all day long on factory parts with a load of torque. Depending on which exhaust you use a 3.6 is about the same weight as a 3.0 so no weight penalty as such and will probably be just as quick in the real world as an SC with a 930 or 965 running CIS plus it will give you a chunk more mpg.

The sensible money is to do an NA 3.6, if money is no object then hit the boost but please approach it with eyes wide open.

[Sauriel]

I want EFI anyway. Motec M84. So thats a constant.

My rebuilt has brand new Mahle Nikasil Cylinders and forged Mahle 9;8;1 pistons too....


I would want a EFI Motec M84 Turbo-engine though, 400-500 bhp no problem ?

[Jevvy]

Sauriel said:

I want EFI anyway. Motec M84. So thats a constant.
My rebuilt has brand new Mahle Nikasil Cylinders and forged Mahle 9;8;1 pistons too....
I would want a EFI Motec M84 Turbo-engine though, 400-500 bhp no problem ?

Any bhp is possible when you add boost, how long it lasts and what its like to drive is the important bit. Sure it will be fun but anything over about 400bhp needs wider rear rubber than a narrow body can provide unless you want to baby the throttle in everything but 5th gear, thats probably why ruf tweaked the rear arches to fit slightly wider tyres.

That said it sounds like a fun project, good luck with it

[Sauriel]

Thanks for the input. As you say, turn-key reliability is #1 for me. this is a street car, for daily driving.

Im open to both 3.6 NA builds as well as turbo, I would like to keep it under 30 grand though all in.

[Jevvy]

30k will get you a very powerful NA 964/993 based motor very close to turbo bhp numbers without the additional weight and headache of adding boost. PM me if you want some contact details.

[BertBert]

I think you'd end up with a huge and super-expensive project. Feels better to sell the SC and buy the car you want!
Bert