![]() |
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
![]() ![]() |
![]() |
vintage914racer |
![]()
Post
#1
|
Member ![]() ![]() Group: Members Posts: 455 Joined: 28-December 03 From: Minneapolis, MN Member No.: 1,473 ![]() |
This past weekend I took my 914-6 vintage racer to the Elkhart Lake Vintage Festival at Road America. My car ran great up to the final feature race on Sunday. Long story short, I was running up front in fourth behind a couple high-budget, blazing fast 911s when my clutch pedal went to the floor while downshifting in a heavy braking zone. I was able to pull it back and regain normal operation for a lap or two when it happened again and sidelined me for the rest of the race.
![]() Well, tonight I pulled the tranny to assess the damage and the problem is clear -- a blown clutch. It now sits on my bench in three pieces. ![]() I have a few questions for the wrenches wiser than me on these forums: 1) Should I be concerned about some underlying issue causing the failure? 2) Is it worth upgrading to a lightened flywheel and racing clutch kit? My understanding is these early flywheels are pretty light to begin with. For reference, the car is running a 2.5l six putting out somewhere around 250hp. 3) Given the state of the clutch and what was spinning around on the flywheel, is it reasonable to think the current can be resurfaced, or am I destined for a new flywheel? Any and all input would be appreciated. ![]() |
Mikey914 |
![]()
Post
#2
|
The rubber man ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 12,767 Joined: 27-December 04 From: Hillsboro, OR Member No.: 3,348 Region Association: None ![]() ![]() |
Yep, that would do it
|
Superhawk996 |
![]()
Post
#3
|
914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 7,005 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch ![]() ![]() |
Resurface (assuming material is there to do so within factory spec) and move on.
This looks to be a 914 flywheel on a six? Likewise a 4 spring clutch disc. Are you running the 901 transmission? If so that clutch / trans was never intended to take 250 HP if that is what you have. Clutch should be viewed as a fuse if this is indeed the case. |
wndsrfr |
![]()
Post
#4
|
Senior Member ![]() ![]() ![]() Group: Members Posts: 1,449 Joined: 30-April 09 From: Rescue, Virginia Member No.: 10,318 Region Association: MidAtlantic Region ![]() ![]() |
Yep, that would do it Just had the same thing happen to me.... look at my post in the Paddock section. Call Kennedy... get a proper racing puck clutch with 901 splines and the spring hub. They shipped one to me last week via priority mail... had it here across the country at noon of second day. |
johnhora |
![]()
Post
#5
|
Senior Member ![]() ![]() ![]() Group: Members Posts: 883 Joined: 7-January 03 From: Derby City KY Member No.: 107 Region Association: None ![]() ![]() |
Nice racer 914...show us some more pics.
Looks like a stock disc and pressure plate...how many hours on those? Need something a little stronger or change stock ones often. Kennedy and Center-force work well for track use. As mentioned check flywheel for in spec measurements...if in should be fine..they are tough. As for a lighter flywheel...there was a GT ones...here are pics. ![]() ![]() ![]() |
brant |
![]()
Post
#6
|
914 Wizard ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 11,945 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains ![]() ![]() ![]() |
more flywheel options that work well on race 901's
the aluminum 5.5 has proven much more robust than the steel 5.5 which I broke the 901's become NOT cost effective at 200hp on the track the annual rebuilds... Cooling my 901 has so far doubled the life expectancy for high RPM use. Attached image(s) ![]() ![]() ![]() |
vintage914racer |
![]()
Post
#7
|
Member ![]() ![]() Group: Members Posts: 455 Joined: 28-December 03 From: Minneapolis, MN Member No.: 1,473 ![]() |
Yep, that would do it Just had the same thing happen to me.... look at my post in the Paddock section. Call Kennedy... get a proper racing puck clutch with 901 splines and the spring hub. They shipped one to me last week via priority mail... had it here across the country at noon of second day. I will investigate. Does Kennedy provide the pressure plate as well, or just the clutch? more flywheel options that work well on race 901's the aluminum 5.5 has proven much more robust than the steel 5.5 which I broke the 901's become NOT cost effective at 200hp on the track the annual rebuilds... Cooling my 901 has so far doubled the life expectancy for high RPM use. I hear you. The lesser built engines I used to run over the years played nicer with the trans. I just added cooling this season after I found I was cooking the fluid. Have to get the stack rebuilt again this winter... Who makes the setup you have, Brant? I’ve had my eye on the JB Racing setup. Seems to have a good reputation. Looks like there’s been a few failures with the Patrick lightweight flywheel kit |
sixnotfour |
![]()
Post
#8
|
914 Wizard ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 10,805 Joined: 12-September 04 From: Life Elevated..planet UT. Member No.: 2,744 Region Association: Rocky Mountains ![]() ![]() ![]() |
QUOTE Looks like there’s been a few failures with the Patrick lightweight flywheel kit Ive got 3 of them from different owners , bad starter ring gear, the whole flywheel seems soft |
brant |
![]()
Post
#9
|
914 Wizard ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 11,945 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains ![]() ![]() ![]() |
My flywheel came from beck. But I think pms sells the same one
It’s held up for over 5 years and beck used to run the same without problems He also had good reliability to n arguably one of the fastest 2.5 914/6 cars ever built Around 1600 lbs and around 305hp |
wndsrfr |
![]()
Post
#10
|
Senior Member ![]() ![]() ![]() Group: Members Posts: 1,449 Joined: 30-April 09 From: Rescue, Virginia Member No.: 10,318 Region Association: MidAtlantic Region ![]() ![]() |
I will investigate. Does Kennedy provide the pressure plate as well, or just the clutch? Kennedy does have pressure plates...I'm pretty sure mine's a stock Sachs one though. The clutch disc was only about $160, not bad at all. My flywheel is AASCO aluminum with a steel starter ring gear & replaceable friction surface disc. That was $600 a couple of years ago. FWIW if your flywheel is in spec I'd suggest just install a Kennedy clutch disc, scratch up the surface of the flywheel & pressure plate with 80 grit sandpaper & drive it... |
SirAndy |
![]()
Post
#11
|
Resident German ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Admin Posts: 42,199 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California ![]() |
I contacted Kennedy after i burnt up my previous clutch and they made me a special version (not listed on their website) that can take the torque from the 3.6L and still work with the 901.
That included the pressure plate and clutch. So far, so good ... (IMG:style_emoticons/default/driving.gif) |
vintage914racer |
![]()
Post
#12
|
Member ![]() ![]() Group: Members Posts: 455 Joined: 28-December 03 From: Minneapolis, MN Member No.: 1,473 ![]() |
I will investigate. Does Kennedy provide the pressure plate as well, or just the clutch? Kennedy does have pressure plates...I'm pretty sure mine's a stock Sachs one though. The clutch disc was only about $160, not bad at all. My flywheel is AASCO aluminum with a steel starter ring gear & replaceable friction surface disc. That was $600 a couple of years ago. FWIW if your flywheel is in spec I'd suggest just install a Kennedy clutch disc, scratch up the surface of the flywheel & pressure plate with 80 grit sandpaper & drive it.. Kennedy sounds like a winner, and a relatively cheap one at that. The general consensus seems to be that my flywheel is probably fine. I’m thinking about having it lightened RSR style at Ollie’s. Any wisdom from folks on this approach? I contacted Kennedy after i burnt up my previous clutch and they made me a special version (not listed on their website) that can take the torque from the 3.6L and still work with the 901. That included the pressure plate and clutch. So far, so good ... (IMG:style_emoticons/default/driving.gif) I’m going to reach out and see what they recommend. Glad to hear they build to suit if you will |
vintage914racer |
![]()
Post
#13
|
Member ![]() ![]() Group: Members Posts: 455 Joined: 28-December 03 From: Minneapolis, MN Member No.: 1,473 ![]() |
Spoke with Kennedy about options. I'm leaning toward their race spec clutch that works with existing flywheel and PP. Toying with the idea of having Ollie's shave some weight off of the OEM flywheel. Anyone done this?
|
rick 918-S |
![]()
Post
#14
|
Hey nice rack! -Celette ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 20,931 Joined: 30-December 02 From: Now in Superior WI Member No.: 43 Region Association: Northstar Region ![]() ![]() ![]() |
I have a clutch failure on an Isuzu Trooper we owned. I had the shop just do the disc. Got 4 blocks away and PP failed. Cost me twice. (IMG:style_emoticons/default/slap.gif) wife was not happy
|
rick 918-S |
![]()
Post
#15
|
Hey nice rack! -Celette ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 20,931 Joined: 30-December 02 From: Now in Superior WI Member No.: 43 Region Association: Northstar Region ![]() ![]() ![]() |
Did a lightened flywheel on the 2.0 in 7 of 9. It was a noticeable difference. The guy that purchased her said the car is faster than his factory 6. The engine will rev faster. The down side on a street car it will also decel faster and sometimes stall the engine. Not an issue on a race car.
|
![]() ![]() |
![]() |
Lo-Fi Version | Time is now: 26th April 2025 - 05:34 PM |
All rights reserved 914World.com © since 2002 |
914World.com is the fastest growing online 914 community! We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ... |