Pelican Parts
Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   Pelican Parts Technical BBS > 1- Porsche Technical Forums > 911 / 930 Turbo & Super Charging Forum

Reply
 
LinkBack Thread Tools Rate Thread
Author
Thread Post New Thread    Reply
Registered User
 
Join Date: Jul 2003
Location: Glorious Pac NW
Posts: 2,744
Question Pumped-up 915 clutch?

915 Power clutch kit seemed to deal OK with stock 930 power.

Unscheduled rebuild and restrained bolt-on goody frenzy ensues. Seemed just fine during break-in, made about 395 HP/350 ft/lbs (crank) when we checked the AFRs.

Seemed just fine for a while longer, too.

Now the clutch is obviously not happy and is polishing the flywheel with less provocation each time. It's got to come out and soon.

I want to pull the trigger on buying parts in the next few days, but I'm undecided what to put back in (although I'm leaning towards a Sach competition cover).

What you guys with 915's and > 300 ft/lbs torque running for a clutch setup, how much (if any) difference in streetability is there, how long are they lasting you and how much power/torque is your motor making ?

Thanks for any help!
__________________
'77 S with '78 930 power and a few other things.
Old 07-21-2007, 06:22 PM
  Pelican Parts Technical Article Directory    Reply With Quote #1 (permalink)
Crotchety Old Bastard
 
RarlyL8's Avatar
 
Join Date: Jan 2000
Location: Huntsville, AL
Posts: 13,257
Garage
The Sachs sport clutch is really nice for a street car. I'd put another one in. They don't like drag racing but niether does the 915!
__________________
RarlyL8 Motorsports / M&K Exhaust - 911/930 Exhaust Systems, Turbos, TiAL, CIS Mods/Rebuilds
'78 911SC Widebody, 930 engine, 915 Tranny, K27, SC Cams, RL8 Headers & GT3 Muffler. 350whp @ 0.75bar
Brian B. (256)536-9977 Service@MKExhaust Brian@RarlyL8
Old 07-21-2007, 07:16 PM
  Pelican Parts Technical Article Directory    Reply With Quote #2 (permalink)
Registered User
 
Join Date: Jun 2002
Posts: 458
I have a centerforce dual with around 400hp and 375T. The
pressure plate has 33% more clamping force than stock. I
don't care for the disc. It takes a lot of foot pressure. I
wonder about my cable breaking. I really need a hydralic
clutch with that pressure plate. It seems that with kevlar
clutches you get a lot of chatter. They are on or off.
Old 07-21-2007, 07:23 PM
  Pelican Parts Technical Article Directory    Reply With Quote #3 (permalink)
Registered User
 
Join Date: Jul 2003
Location: Glorious Pac NW
Posts: 2,744
Cool, thanks.

Brian, do you have a part # for the Sport clutch? Any specs? (I can probably get the latter with the part #'s...)

Is it a complete kit or an uprated plate? I'm told Sachs do a pressure plate they rate @ 350 ft/lbs, and I'm wondering if that's the same as you're referring to.

The power clutch had an original # (for the kit) of 3000961101, which apparently references or supercedes the following parts:

91511691100
91511600116
91511600127
91511601122

Must look up all the part #'s...

Jess, thanks for your reply too - I was told (by a competition clutch guy) that the 225mm Sachs 915 organic friction plate is rated (by Sachs) @ 600 NM, or about 442 ft/lbs. I was considering trick friction materials until I heard that...

Another competition clutch guy told me that all ratings quoted by Sachs have a 20-25% margin built in. (He was talking specifically about pressure plates in that instance, mind you - but seems like a fair bet it's across the board)...

KEP told me that their Stage 1 kit (which they rate @ 417 ft/lbs) uses the stock Sachs friction plate with their pressure plate.

One of the clutch guys I spoke to laughed when I mentioned the 930 motor and the Power Clutch, said "yeh, that won't work" and told me that the Power Clutch is a stock 915 pressure plate, and they just cherry pick the top 10% of the batch into the Power Clutch boxes (like Harley did for Cafe Racer motors in the 70's)... So there's apparently a pretty fair chance you could buy a stock Sachs clutch kit and end up with one with an identical rating to a Power Clutch...

Seems to me a pressure plate rated @ 350 ft/lbs with a 25% margin will hold up to 437 ft/lbs, which seem to be a good match for the stock friction plate.

I like off-the-shelf stuff, but I don't want to have to get a gym membership to change gear...
__________________
'77 S with '78 930 power and a few other things.

Last edited by spuggy; 07-22-2007 at 07:23 AM..
Old 07-22-2007, 07:20 AM
  Pelican Parts Technical Article Directory    Reply With Quote #4 (permalink)
Registered User
 
Join Date: Nov 2005
Location: oregon
Posts: 77
Garage
So what did you end up buying? How do you like it?
I myself am going to replace the clutch in my supercharged 911 carrera (1986) $340 HP. Too much power for standard clutch.

I drive on the street and rarely go to track events. I was thinking the Sachs Sport clutch might be good, but ive heard good things about Spec stage 3 clutch, and Kennedy. The Centerforce duel friction clutch sounds to be too extreme. "either your in gear or out, no in between"

Any follow up ?
__________________
Tauran
1986 911 Carrera Targa 3.5L Supercharged
Needful Toyz LLC
www.needfultoyz.com
Tauran@needfultoyz.com
Old 06-13-2008, 09:44 AM
  Pelican Parts Technical Article Directory    Reply With Quote #5 (permalink)
A fellow Pelacanite
 
NathanUK's Avatar
 
Join Date: Nov 2006
Location: UK
Posts: 2,002
Garage
Stock disc and a KEP pressure plate would be good. They offer different stages.
__________________
1981 UK 930. G50/01 shortened, 964 3.8RS Fibreglass Body Kit, 18" Alloys 8.5" F & 10" R, 225's F & 285's R, Special Colour Metallic Blue Paint, FIA Sparco Evo's, A/C and Air Pump removed, Electronic Boost Controller, GHL Headers, Tial46 WG.
Fitting - New service kit.
Needs Fitting - Innovate XD-16 Kit, Kokeln IC. Stephen's K27 HFS, EVO Intake Assy & his Modded USA Fuel Head.

1983 UK 911 3.2 Carrera Sport Coupe. Black, Black Leather with Red Piping, Black Alloy Gear Knob, K&N Air Filter Element, Turbo Tie rods.
Needs Fitting - K&N CO Sensor, Round A/F Dial Gauge, Factory Short Shift Kit.

http://www.danasoft.com/sig/Iamnotanumber.jpg
Old 06-14-2008, 02:52 AM
  Pelican Parts Technical Article Directory    Reply With Quote #6 (permalink)
 
Now Available for Ordering:   101 Projects For Your BMW 3 Series 1982-2000  [more info]
Registered User
 
Join Date: Jul 2003
Location: Glorious Pac NW
Posts: 2,744
Quote:
Originally Posted by ivallt View Post
So what did you end up buying? How do you like it?
I myself am going to replace the clutch in my supercharged 911 carrera (1986) $340 HP. Too much power for standard clutch.

I drive on the street and rarely go to track events. I was thinking the Sachs Sport clutch might be good, but ive heard good things about Spec stage 3 clutch, and Kennedy. The Centerforce duel friction clutch sounds to be too extreme. "either your in gear or out, no in between"

Any follow up ?
I spoke to a few people, including Kennedy who were fairly helpful. I don't recall exactly why I didn't go with them, but something bothered me at the time. I don't recall exactly.

I used a Sachs competition pressure plate, and just replaced the stock friction plate.

Pedal pressure is higher than stock, but the clutch doesn't slip. Not at all. I checked.

Got about 8,000 miles on it now, seems to be holding up well.
__________________
'77 S with '78 930 power and a few other things.
Old 06-14-2008, 10:22 AM
  Pelican Parts Technical Article Directory    Reply With Quote #7 (permalink)
Reply

Thread Tools
Rate This Thread
Rate This Thread:

 


All times are GMT -8. The time now is 02:36 PM.


 
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2016 Pelican Parts - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page
 

DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.