Turbo vs. Carrera Dimensions

DSPTurtle · 09-04-2011, 12:28 PM

It's too early in the day for me to be drunk... is it possible that a 1986 Narrowbody Carrera is one inch shorter from shock tower mount to motor mount then a 1985 Turbo Widebody?
I just measured it and had my neighbor measure it too. I can't get the 3.3T motor/trans to fit in the narrow body right now so I started taking measurements.
Is this even possible?

Thanks in advance!

Ken911 · 09-04-2011, 04:22 PM

ok i have an 88 turbo. on the bottom of the car when the transmission cross member bolts in. there are two sets of holes about an inch apart. I think that maybe the reason yours will not fit is that the cross member for a 915 tranny is different than the one for a 930 tranny. Just a thought if you still have the engine and tranny you took out you might want to compare some measurements.

RarlyL8 · RarlyL8's Garage

The late 930 tranny is 1" longer than the 915. The mounts are in different locations.
To keep the 911 dimension you need the early 930 tranny or modify the late 930 tranny.

MrShades · MrShades's Garage

I have a 85 narrow body with a 3,3 engine. But it was not me that did the twin turbo convertion so it might be a 3,2 engine with 3,3 cylinders?

But i really did not think that there is any difference between the 3,3 l engine and the 3,2 l engine?

911TT33 · 09-05-2011, 01:03 AM

Quote:

Originally Posted by MrShades

But i really did not think that there is any difference between the 3,3 l engine and the 3,2 l engine?

They have the same bottom end, but the Carrera is EFI and the 930 uses mechanical injection. The material the 930 heads are made of is different too, and the inlet and exhaust ports are smaller on the 930 motor.

DSPTurtle · 09-05-2011, 05:21 AM

Brian,
Are you saying that there were two different dimensions for the 930 (4 speed) gearbox depending on the year produced???

As for all the other comments, the tranny mount was fabricated to fit a 930 gearbox and a 911 chassis.

I pulled the trans mount off and got the engine to fit in the engine bay but did not get the trans to bolt up in the front. I fear that the nose of the tranny is hitting the torsion tube.

JFairman · 09-05-2011, 06:23 AM

The 930 bellhousing was around an inch shorter during the first 2 or 3 years because they used a narrow spring center clutch disc and pressure plate back then.

Then Porsche and Sachs got stupid and started putting a big thick rubber center clutch disc and thicker deeper pressure plate to fit over it and made the bellhousing deeper and longer to fit it in there.

I have no idea why they did that, the spring center disc works fine and lets the motor mount around an inch forward in the chassis and the rubber center disc dry rots, cracks, and breaks apart and costs more to replace.

Most people replace the rubber center 930 disc with a spring center disc. Then you can also replace the Sachs pressure plate with a KEP stage 1 aluminum pressure plate that weighs around 12 pounds less and has a deep aluminum basket frame to take up the extra space in the stock 930 bellhousing.

Or you can have the 930 bellhousing shortened, install the narrow early 930 pressure plate and move motor around an inch forward in the car. Seems the rear motor mount must be different or maybe it uses a spacer to allow that.

RarlyL8 · RarlyL8's Garage

Yes, as Jim explained the 930 tranny gained an inch in 1978 when the engine went form 3.0L to 3.3L.

DSPTurtle · 09-05-2011, 07:27 AM

I get it... but I need the engine to stay back where it is and the tranny to be about an inch shorter in the front. I already went with the 1978 clutch setup but used the big aluminum spacer ring and T/O bearing extension. It would be nice to shorten the bellhousing by an inch, but I wonder if I can move a few key sheet metal points with a BFH.

MrShades · MrShades's Garage

One in my local Porsche club put a G50 in but that took a lot CNC machining to shorten the house of the transmission and axle.

Is it the axle that is to long?

TurboKraft · 09-05-2011, 09:37 AM

Turtle,

Yes, you need the engine to be in the same position to make the engine mount line up, plus the engine cooling tins / sheetmetal, exhaust, etc.

The Turbo's case, engine console (steel bracket around the pulley) and engine mount crossbar are dimensionally the same as the Carrera's.

If you put the engine & gearbox into the chassis, are you saying the transmission crossmember holes do not line up with the chassis' holes?
Is your gearbox clearing the torsion tube housing completely?

As far as I know, only the 1987 chassis had 2 sets of gearbox mounting holes depending if the car got a Turbo/4-sp or Carrera/G50 drive train.

Ken911 · 09-05-2011, 10:35 AM

Quote:

Originally Posted by TurboKraft

Turtle,

Yes, you need the engine to be in the same position to make the engine mount line up, plus the engine cooling tins / sheetmetal, exhaust, etc.

The Turbo's case, engine console (steel bracket around the pulley) and engine mount crossbar are dimensionally the same as the Carrera's.

If you put the engine & gearbox into the chassis, are you saying the transmission crossmember holes do not line up with the chassis' holes?
Is your gearbox clearing the torsion tube housing completely?

As far as I know, only the 1987 chassis had 2 sets of gearbox mounting holes depending if the car got a Turbo/4-sp or Carrera/G50 drive train.

mine is an 88 and has 2 sets of holes about an inch apart.

DSPTurtle · 09-05-2011, 11:50 AM

It appears that the little brace pieces for the torsion tube are getting in the way (you can see the shiny metal right above the trailing arm mounting nuts)...

I am not sure if, once those are out of the way, the torsion tube will need any massaging. I think the first step is going to be to "move" those brackets a little bit.

Tilikum Turbo · Tilikum Turbo's Garage

I dropped in a 3.3L stock engine into a 83' 911SC mated to a modified 915 tranny(internally) with no dimensional issues whatsoever.

DSPTurtle · 09-05-2011, 12:59 PM

Quote:

Originally Posted by Tilikum Turbo

I dropped in a 3.3L stock engine into a 83' 911SC mated to a modified 915 tranny(internally) with no dimensional issues whatsoever.

I thought you had a shop do it?

DSPTurtle · 09-05-2011, 01:08 PM

I think this picture shows it best...
After moving those little triangle brackets, here you can see the nose of the tranny butting up against the torsion tube. I am wondering how "bad" is it to beat the torsion tube flatter in that one area...

WinRice · 01:46 PM

I'm under mine as we speak.

For reference, the dimension I have from the front most trans bolt centerline to the edge of the pan is right at 2.0", in relation to your pic above.

I have the two sets of holes on my 86, look at the second pic down just behind the mount:

935 Suspension with Moton Coilovers for the street

DSPTurtle · 09-05-2011, 02:49 PM

After staring at that picture I posted above for about 30 minutes, I realized that it was an angle issue. If I could get the engine up and the trans down, that webbing is at such an angle that it will not contact the torsion tube.
So, at the end of the day, once I moved those little triangle braces back a little bit she popped right in. There are about a million jokes I want to make right now that would really get the Mods thinking twice about letting me post.
Let's just say that I am at least gonna leave it in there overnight so it can get used to the feeling. Thanks for the help Pelicans!

TurboKraft · 09-05-2011, 09:26 PM

Quote:

Originally Posted by Ken911

mine is an 88 and has 2 sets of holes about an inch apart.

Sorry, I meant to say 1987- onwards, so all 1987-89.

DSPTurtle · 09-06-2011, 06:59 AM

Quote:

Originally Posted by IndianDrives

I think maybe the reason you can not fit, that the beam 915 is different from a transsexual trans 930. Just a thought, if you still have the engine and trans removed you should compare some measures.

Did he just call my car a transsexual? Was it a girl before the engine swap? Wow... what gives on that post??? LOL