S52 n/a Flywheel - Clutch Setup

[RobertK]

ive used a S52 crank engine with 12-13lb fly and OEM m5 clutch no problems for 8years on a DD car. it was supposedly balanced with the entire bottom end assembly and i had to send everything off for that. not sure what they actually do. it still rattles at idle on occasions take up is nice but its not light enough....

Good call on the balanced bottom end.

For every UUC horror story, there are 10 guys who run it with no issue. I have had mine on for 2 years and taken long (1000 mile) drives without issue. Yes it chatters, yes I will open it up and retorque everything sinces it's been about 10k miles since install. But hot Damn does it make the engine rev happy, and grab like crazy.

I guess I just view those parts more as wear items than permanent fixtures. My e30 is purely for fun, so whatever makes it more fun is what I'm going to use.

Opposite experience here. I know 1 person out of 10 that have kept it. If I were hell bent on having a super light flywheel I would do it as part of a blueprinted and balanced build just for pure reliability.

Either way the F1 flywheel is a good choice if you want an affordable and decent single mass flywheel that is lighter than stock but doesn't come with the chatter and potential reliability issues that come with the lighter aluminum flywheels.

Aside from that it comes down to what you prefer. Faster acceleration / easy rev matches or to be faster off the line / smoother shifting.

If the car is a fun street / DD / light track duty car then go F1. If the car is purely for track / competitive racing then you would want to keep the lighter flywheel.. but have your bottom end properly balanced to get the most out of it and avoid potential issues in the future.

[digger]

Good call on the balanced bottom end.

my next engine i will be doing the same but using an alloy FW as opposed to a lightened stock one im thinking of one step above the OEM friction material even though it is probably enough

[Rob@UUC]

Opposite experience here. I know 1 person out of 10 that have kept it.

Honestly, the real-world statistics are the opposite.

For about every 300 units we sell, we get a tech call with a problem.

90% of the time, that one call's problem turns out to be something simple - improperly bled slave cylinder, that sort of thing.

9.9% of the time, that one call's problem turns out to be an installation issue - improperly torqued bolts, no loctite, forgot gall plate, etc.

.01% of the time, what we may diagnose as an actual issue (usually something with the clutch), we replace it for the customer immediately.

There is a reason the UUC flywheel/clutch kits are the #1 selling flywheel/clutch kit for BMW in the world.

How do we know this? Our flywheels are sold by just about every big, reputable distributor across the USA and in other parts of the world. Same companies offer competing brands... and they tell us of all the other brands combined, they sell 1 or 2 for every 10 UUC flywheels they send out.

So do you hear about problems on message boards? Of course you do - that's what people do on message boards - post problems!

But the statistics don't lie. 100% American made, SFI certified, commercially the most popular, and by our design criteria, the best possible. That's the truth.

[RobertK]

I couldn't resist.

[digger]

so rob is the UUC Performance Organic a PITA for a daily driver and noticeably worse compared to the OEM M5 clutch?

[MR E30 325is]

so rob is the UUC Performance Organic a PITA for a daily driver and noticeably worse compared to the OEM M5 clutch?

I am running the performance organic clutch disc and although I never used the stock disk, I don't feel any issues with my current setup.

I DD my 'racecar' E30 just about everyday, in a multitude of climates (Hot as balls Phoenix, cold as balls Flagstaff, in the snow, etc.) and the clutch is the least of my worries.

Just be good with your left foot and you're golden.

[Rob@UUC]

so rob is the UUC Performance Organic a PITA for a daily driver and noticeably worse compared to the OEM M5 clutch?

Just the opposite! It drives completely normally, like a standard OEM organic clutch.

The difference with the Performance Organic is simply that it has more torque capacity and the better organic formulation is resistant to higher temperatures (will take more hard use/abuse).

[RobertK]

Honestly, if you're dead set on an aluminum flywheel I would say go with a quality JB Racing flywheel. UUC and F1 sell more flywheels because they are cheaper. Do a Google search for UUC flywheel failures and then do a search for JBR flywheel failures.

So do you hear about problems on message boards? Of course you do - that's what people do on message boards - post problems!

Sorry if I believe this is a total cop out. Only a certain percentage of people who have a bad experience will take the time to air out their problems on an internet forum and you sir have lots of disappointed customers. I am willing to bet for every person that has complained about you online there is an equal number of people who were also disappointed but just didn't take the time to do the same.

[golde30]

I ran the f1 spec chromoly flywheel with Sachs m3 clutch kit, and it chartered just as much as my UUC setup, if not more. As far as clamping force, I have no complaints about either.

[digger]

Honestly, if you're dead set on an aluminum flywheel I would say go with a quality JB Racing flywheel. UUC and F1 sell more flywheels because they are cheaper. Do a Google search for UUC flywheel failures and then do a search for JBR flywheel failures.



Sorry if I believe this is a total cop out. Only a certain percentage of people who have a bad experience will take the time to air out their problems on an internet forum and you sir have lots of disappointed customers. I am willing to bet for every person that has complained about you online there is an equal number of people who were also disappointed but just didn't take the time to do the same.

i'm after a 240 mm clutch assy for M20 engine, only ones i know about are:
- UUC or
- Metric mechanic lightened steel FW with OEM M5 clutch that i have now

price aside why are JBR "better" than the others?

[Fernflex]

I don't think UUC is bad but in my case my car has UUC blue fw it sounds alot in idle but I dont care about that but also Im using the m5 clutch kit with no more than 6,000 miles of use and fifth gear is grinding and if you shift after 7,000 rpm the next gear the clutch do not hold the power and you feel it spin.

I will maybe change to F1 Fw and the stock M3 clutch because of pricing, a new M5 clutch kit without the new friction plate cost more than a brandnew F1 fw and m3 clutch kit.

[Fernflex]

Update

I think I found a problem, my car has the e36 getrag tansmission and the stage 1 fw m5 clutch and m3 pressure plate. The problem I was having I think it was caused because the input shaft of the getrag is smaller than the shaft in the zf. The clutch and everything was slipping and not moving with the shaft.

[mpowerful]

I read this entire thread then got to the last post.....and all i can think is....wait, what?!?

[Fernflex]

My mech told I was wrong, so forget my last comment.

[IronFreak]

i'm after a 240 mm clutch assy for M20 engine, only ones i know about are:
- UUC or
- Metric mechanic lightened steel FW with OEM M5 clutch that i have now

price aside why are JBR "better" than the others?

you can bolt an m50 starter to the m20 and use any s5x flywheel/clutch combo you want on the m20. plus....bigger grip surface.