Ode to the 930 4 speed
 

Always thought it was cool that the 930 had 4 speed gear boxes vs the regular 5 speed gear boxes in other porsches.

I remember the first time I saw a 930 at the porsche dealership.. early 90s how completely odd and cool to see the shifter with just 4 ratios!

To me this has become a CENTRAL PART of the 930 experience beside of course the LAG.

Looking down and seeing that classic 4 speed which can only mean this is a 930 turbo!

Anyhow a lot of flak over the years for this transmission by those who most likely never experienced driving a 930..

I can say that the 4 speed is FASTER on brute acceleration 0-60 and 0-100 than a 5 speed. I’m not of the opinion shifting the 5 speed faster than the 4 speed is possible.. At least not without destroying the 5 speeds synchronized mechanisms.

Looking back 40 years later it makes perfect sense why porsche choose the 4 speed for the 930.

It was the STRONGEST transmission porsche had at the time. Capable of handling 700 + hp.

Today it makes it that much cooler being a 4 speed over the 5 speed found in everything else.

That and the 930 4 transmission was also FIA homologated which is super cool!






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4 speed transmissions were available much earlier than that. My '67 normal came with a 901 4 speed. I've replaced it with a dog leg 5 speed though. I still have the original if you want it. 50K miles, shifts great and the synchros are excellent. I'll never put it back into my car and I'll sell it cheap!

^ Does the ‘67 do 92 mph in second gear though? ;)

Uh....no. had it up to 95 in third though. A certain CHP officer can attest. :-)

several years ago I picked up a 78 SC/930 conversion, not running project.

the guy built this car with a 3.3 turbo engine, and what turned out to be a mag case 915, 7:31 and 2-4 autocross gearing, with a TALL 5th. sold the gearbox to a friend and when he was rebuilding said the gears were very burned and surprised it had not blown up.

I'll be getting a proper 930 4sp, either a short BH or have one shortened. if I have to rebuild to shorten, may regear 2-3 a little tighter. we'll see.

all the engine stuff is about to ship to Steve Weiner for machine work. I'll have him do the gearbox too.

The 930 four speed was so great...that Ruf designed a proper five speed.

I mean, what the hell? Next you'll be waxing philosophic on the lovely 3LDZ turbo unit...

Rubbish. Borg Warner synchros are so superior to Porsche's balk ring design.

https://www.youtube.com/watch?v=nFYH4MntnVg

ps. The 901 was FIA homologated. The 915 was FIA homologated. The G50 was FIA homologated. Every car Porsche has ever raced got it's gearbox homologated. I do not think that word means what you think it means... :rolleyes:

Ode to the 930 4 speed
 

The 4 speed is faster for hardcore acceleration which is what a 930 is for..

I’m sorry but the tall gears just work better with the MASSIVE torque a 930 produces on boost..

I really dont think the gears on five speeds are correct for 930s or at least work well with the on and off power delivery..

Also none of you can ROW gears fast enough on a 5 speed to keep up with a 4 speed..

On boost the 4 speed is a rocket ship that you only shift once below 92 MPH..

I know on paper the 5 speed seems faster but in reality at least for acceleration it’s not..

You can’t shift 5 gears faster than 4...

That simple.


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I gotta be honest I wish my 4 speed had 5 cogs. I like doing backroad twisty driving and I always feel like I'd love a gear between 2nd and 3rd. Someday I'd like to get shorter 2,3,4 gears. Might cause RPM's to be a tad too high cruising the highway, but I don't use the car for that too often.

If you're not a purist throw some low profile tires on. Same result, mo cheapa

I have the short bell housing tranny in my car 1st-65 2nd-100 3rd-about 130. never ran 4th to redline lol.
I have aEFI turbo motor and works very well with the 4sp.
I would trade it for a good 5 speed in a heart beat. I run my car up against pretty big HP cars
(vette Z06 ,etc ). Most guys running my car at the track Quarter mile are running faster times with proper 5 speeds. Dont get me wrong with big power it is nice to not shift as much. I really dont think you would be going backwoods in speed. I think the 5 speed would be an upgrade all the way..
John

You're not paying attention. Or maybe you don't know the car I posted. That's Eddie Bello. It's a 964 turbo. It had a G50-52 gearbox in it. That's a taller geared turbo 5spd gearbox. I don't know what generic 5spd you are arguing against. I am offering up a real gearbox from a real car that Porsche built and sold. Same ratios were in the G50-50 in 1989 if you want to keep it to G body 930s.

0-60, both your 930 and his 50-52 will require 1 shift. 0-100, both his 50-52 and your 930 will require 2 shifts. His does top out 2nd at 83 mph versus your 92mph. In a 0-100 contest it's totally inconsequential.

However, what will make a difference if you both line up at the drag strip is the synchro design. Even a monkey can shift a G50 faster than the balk ring synchros in a 930. Your comment that you can't shift 5 gears faster than 4 makes no sense in practical analysis. Why? Because it's the same number of shifts in both gearboxes. The number of gears in the box means nothing.

I have owned a 1987 turbo cab for about 10 years, always thought it was a 930 with a G50 conversion. Turns out she was born as a narrow body with a Targa roof. Looks like, sounds like, runs like a 930 but without the proper vin. I cannot make a 4 speed comparison, but can say the G50 rocks. Pulls 140 mph in 4th gear at redline. I have not pushed 5th gear for ant more speed.

The 930 box is cool and sturdy, but it was outdated when new. 4 gears was not a feature, it was a limitation.
I run a 4speed 915 in my 77. I like the tall second gear, but the step between the next is to long.
A G50 is sweet and heavy, but the weight is worth it.

I had an 81 Turbo 4 spd then a 91 Turbo G50 5 spd, the 5sp transmission made it far easier to stay on the boost. RUF new this when he added a 5th to the box. Of course on the highway 3d and 4th were perfectly sufficient with all the torque.

I wish my 915 had 6 gears.

They really just need a usable 1st gear. 2.78 or 2.64 are just about right.

There is little subjectivity when the data supports the facts. The OP made some strong statements based more on passion than fact. Matt's post support the facts.

I had a 76 turbo in 1978 with an RSR 915. Not many choices back then. The motor was around 360 hp. I had the opportunity to see results back to back. Hands down the 915 gets it done better than the 930. To be fair the 915 is far from a slick shifter but it is still less balky that the 930.

There are plenty of reasons to support taller gears and less shifting. For the turbo that tall gearing created some extra load and needed exhaust heat. Porsche had no choice but to increase gear width and center distance to handle the perceived loads the race cars were going to see. Even if they wanted to poke 5 speeds into the street turbo of the day I would think they did not want to shake up the chassis to package that large gearbox for such low volumes. Look what was needed for the G50 in the Carrera.

To also support the statement on the Borg synchro's, Porsche's design can not hold a candle to them. They had their place back when they replaced sliding gears but the B&W paper synchros in the G50 represent what continual improvement is all about.

He does that each time he states that the factory turbo lag from that horrible turbocharger is good (character) and should not be changed for a unit that spools much earlier and does not run out of steam shortly after it hits. :D

consider the context, matt. pretty sure he's never seen 92 in second gear given how he treats his car.

nonsense...