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914World.com _ 914World Garage _ Clutches?

Posted by: technicalninja Jan 11 2024, 01:48 PM

I've seen a bunch of clutch options that are available and had questions.

What's up with all the different diameters?

Is there one size that has more or better options than the rest?

I've found a decent price on a stock 2.0 Sachs kit and am leaning this way now.

I'm hoping this thread will alter or prove my decision.

What will a properly installed and bedded stock 2.0 set up hold in torque?

I'd be tickled pink if ya'll say 200lbs./ft...

I do not expect to exceed this number, but I don't want to spend money on something I have to replace again shorty down the road.

If you were provisioning for 200lbs./ft which clutch would you chose?

Hoping for a PINK ninja here!

Afterthought: Are there differences between 2.0 / 1.8 flywheels?
I didn't think there were but am not sure.

Posted by: Jack Standz Jan 11 2024, 01:57 PM

We've run Centerforce dual friction clutches in 914s and other vehicles on the street.

https://www.summitracing.com/parts/ctf-df191198

All 914 flywheels are all functionally the same. Have a good German one machined versus getting a new one (unless you're using a conversion flywheel to put a type IV motor in a bug). The old flywheels are better than the new ones which tend to be softer. While you're at it, you can have them lighten it. And, it's probably less money than a new one too.

The different sizes are because the flywheels from type IV buses are not the same and use a different size clutch.

Posted by: technicalninja Jan 11 2024, 02:45 PM

Thanks Jack!

That's a nice clutch and I've used Centerforce many times in the past.

I was aware of the crappy new flywheels...

Even Raby posted "brand new German Sebo" got thrown in the trash as it was stupid soft.

I have both 1.8 and 2.0 originals in excellent shape (never machined) so I'm good in the flywheel department.

I'm a SERIOUS engine builder and on a car that is not constrained by rules (not a race car) I'm a HUGE believer in the heaviest flywheel you can find, especially if you have doubled the output. Yep, you accelerate ever so slightly slower but...

The tranny lives 3 times as long!

The heavy flywheel acts as a damper to the individual firing pulses and the input shaft bearing is less "hammered."

The idle is smoother and the car is far less likely to be stalled by poor launch.

AC load is not "felt" as much with heavy flywheel too.

It's not BETTER (except for tranny life!), it's just more user friendly...

This might be MPITO (mouse piss in the ocean) on a 200 hp car but it gets critical on a 400hp car. My 914 will be lucky to see 175 hp.
I am planning mods to increase the available torque throughout the usable range.

Posted by: rhodyguy Jan 11 2024, 03:08 PM

I don’t know if new FW bolts are available. When I did a clutch I had to grind a bit off of the top of the new bolts and then weight them and adj as needed. We were informed the bolts were a one time app due to size/torque/stretch. Also replace the clutch fork cup bushing, the metal retaining clip and the 2 plastic pivots for the TOB.

Posted by: Jack Standz Jan 11 2024, 03:35 PM

Well, some say " heavy car, heavy flywheel & light car, light flywheel." But, of course, run what you want!

We're running that exact centerforce dual friction clutch on a 2056 with a 12.5 lb flywheel. The motor is probably putting out 120 HP plus or minus 10 HP. The car has a custom fiberglass body, including hood, but don't have an overall weight on the car. Everything was dynamically balanced (all reciprocating motor parts, clutch, flywheel, pressure plate). We're very happy with the combination.

Posted by: technicalninja Jan 13 2024, 11:11 AM

Anyone else?

I want to know what a stock clutch can hold.

I've found the German stuff tends to be much heavier duty than they needed from the start.

Posted by: 914Sixer Jan 14 2024, 06:54 AM

Sachs makes a performance kit for the 911/914 early clutches

Posted by: mlindner Jan 14 2024, 07:57 AM

I bought the Sachs six spring clutch kit from Pelican. This is on my 914-6 Tribute running a 2.2L S motor with short gears. Three years now and runs great. #3000-509-001-M38. Best, Mark

Posted by: R Dub Jan 14 2024, 02:33 PM

I have a Sachs clutch in my 2056 since 2019 and zero issues. I actually really like it.

Posted by: 914Sixer Jan 14 2024, 09:43 PM

Here is what I found on the Sachs website, click to open

Kit part number 999741.000064

Attached thumbnail(s)

Posted by: technicalninja Jan 15 2024, 03:00 PM

Thank you, Mark!