911 915 trans swap in 87 930

[dale007cars]

hello ! i am new to forum in the middle of big project and wondering if someone could help me out here ? i am swaping a 915 trans and all rear suspension components in to a 1987 930 turbo shell .wondering if the 915 will fit the 930 tork tube and will trailling arms fit too ? thank you for the help !

[dale007cars]

sorry forgot to mention trailling arms and suspension components from a 77 911.thank you !

[diverdan]

Should pretty much bolt in and some do it so they can use wider wheels and tires. Would I recommend it? No. The 4 speed tranny of the 930 is a real rock crusher and the ratios well suited to the higher torque generated. An early G50 from an 88 3.2 would be a bit better than the 915 if you are going to have any major increase in torque. The major difference as I recall in the 930 trailing arms is in the area of the hub casting and through the hub axle shafts. That could make a huge difference in wheel bearing life.

Dan

[sc_rufctr]

Sorry but I have to ask why would you even consider doing this?

An 87 turbo would be better than most high return investments right now.. And they're only going one way in value.
If you want to go the other way in value then swap in the earlier 911 components.

So don't do it.

[SiberianDVM]

Don't do it if you are use a 930 motor, but if you are just using a 930 roller to build a turbo look NA car, then go for it.

[dale007cars]

i have purchased a bare 930 shell and swapping over all my parts from a 1977 car that was in a bad accident in the front.my big concern is will my power plant 3.5l twin plug 6webber carb and 915 trans fit without and modification to mounting points and will my trailling arms also fit ? thank you for your help !

[dale007cars]

sorry for the upside down pic ! the 87 930 had a g50 4speed from what i can gather and i have a 915 that has been rebuilt .i am pretty shure a g50 5 speed would require a tork tube swap ? first time doing the swap. idealy would like to find and swap g50 5speed down the road but for the the mean time would like to use the 915.thank you guys !

[Matt Monson]

No such thing as a 4Spd g50. That would be a 930 gearbox.

What you want to do will work out fine. Later a g50 5spd can be fit by shortening the bell housing and mainshaft 1.1".

[Matt Monson]

One thing to consider is smog. It is technically illegal to put an engine into a chassis that is newer than the engine. That's federal law. Local enforcement can be all over the place. Some places don't smog an '87 at all. Here anything newer than 1974 is required to get inspected and tested.

[dale007cars]

thank you for the info so far greatly appreciated .

[krasuskyp]

..

[TRE Cup]

uh... NO The turbo trailing arms are shorter than the 74-89 911 and Carrera rear arms. So you would have a ridiculous amount of toe out if you somehow managed to get them all bolted in.
If you do indeed have a turbo tube in there, then you will need turbo arms.

75-77 turbo arms use standard 911 rear brakes and calipers
78-89 turbo arms use the larger turbo calipers and rotors

Problem number two: The G50, and four speed turbo trans (78-98) have different mounting points for the transmission. Your turbo tube should have two mounting holes per side for the transmission, and your pictures shows the rectangular pads of the two position mount. Compare the measurements of the mountings between a turbo and any 69-86 911 between the engine mount center holes and the trans mount center holes. The 78-89 turbo dimensions will differ

Problem number three: As suggested above, the engine mounts are set further back on 78-89 turbos (and 87-89 911) compared to the earlier turbos and non G50 911. Why? The 930 and G50 bellhousings are longer and porsche set the engine mounts further back

Shifter tube in the tunnel? Same till they went to G50. Shifter? a 915 one will have to be used, so you are okay there


Dave

[dale007cars]

thank you TRE CUP for the technical info .wondering if there are brackets that i can use to correct rear trailing arm aligment if i use the 77 rear arms ? i have a set of turbo trailing arms on a 85 cab m491 factory wide body.trying not to take parts from it might be restoring some day trying to keep original.the 77 trailing arms have big brakes now and urethane bushings etc would like to use them if i can install properly ?

problem 2 is engine mount location .are there conversion brackets available to line things up ?

thank everyone here this is great .

[zztot]

Dave (TRE)
Piggybacking onto this question.....but slightly different question
Planning to install 3.6 and 915 box into 930 body(83)
Had shop trial assemble by dropping in an engine and standard 915 trans mount
Seemed to all work
Did we miss something?
Car has 930 trailing arms ( assumed had to)
If it works which axles ( 930 or ?)
I have flywheel, clutch and engine mount stuff and understand those issues to some extent but would appreciate your input on the other issue
Thanks
TOT

[TRE Cup]

Dale007 : the rear arm brackets, on the tube, can be modified to the longer S arms you have. You will need to find someone to make you a couple templates from their standard 911 chassis of the control arm brackets. What you are looking for is an accurate position of the inner through bolt , for each arm.
Before going to the next step, which MAY involve cutting off the turbo position section of each bracket; test fit the S arm and articulate it through it's range of travel. If it does not interfere with the part of the bracket that is oe turbo, GREAT! no more cutting to do. If not, you will have to remove this unused overhang

zztot : Makes sense as the 3.6 mounting bar gets bent towards the front of the chassis on other installs, but most likely straight on your turbo chassis. BUT you must check how far the shift shaft extends into the tunnel, so it can connect with the coupler. IF your 83 930 tub has the two trans mount positions, and you mounted the trans to the forward two holes, you should be just fine with the stock shift tunnel shaft. IF your tub does not have the two options, then you will have to lengthen (splice in short piece of tube) the shaft so the shifter can engage all the gears

[onboost]

[QUOTE=dale007cars;8410995]thank you TRE CUP for the technical info .

problem 2 is engine mount location .are there conversion brackets available to line things up ?

thank everyone here this is great .

dale007cars,
Not that big of a problem, I did one of these conversions a year or so ago for a friend who had a spare engine & trans, and wanted to swap that in his 87 Turbo so that he could drive while he put together his funding for the turbo engine rebuild.

The issue is that the 915 and motor will sit further forward in the chassis that the turbo motor. So the cross mount bar needs a spacer to mount to the engine mount/cradle. I used the stock engine mount bar and welded roughly an inch of round stock tubing to each 4 mounting points and drill & welded/capped each end. Cleaned it up and powder coated it.

Pic 1 gives an idea of thickness and pic two shows how it looks mounted.

[dale007cars]

thank you ! onboost and TRE cup you guys are very helpful .i am looking forward to my swap.