A community of enthusiasts dedicated to Nissan's SR20DE/SR20VE/SR20DET engines.
Start here: forum search. Be sure to search on what you're looking for before posting a new thread.
You are currently browsing the forum as a guest. In order to access special features, the image gallery, and post you will need to be a registered member. Registration is fast, simple and absolutely free so please, join our community today!
If you have any problems with the registration process or your account login, please contact the administrator.
ive read here something about replacing the stock crank pulley to a lighter one (like UR) would be "bad" for the motor in the long run, and i believe even the stock flywheel?
im trying to search for the thread, but can't find it. anybody here knows where is it?
any modification for your car is bad for it in the longrun its how u take car of the car even though we beat on them and slap on as many mods as possible.
replacing the crank pulley with a lighter unit that does not have a dampener in it will cause some added vibration at higher rpms. it is rumored this will cause the rod bolts to vibrate loose and cause you to spin a bearing or worse put a rod through the block. I have seen no real evidence that this is true only some opinion.
Call JWT and ask them about this. They seem pretty adamant about not using a lighter crank pulley like UR. I believe it's because they want that vibration dampening. They do sell a water pump pulley though.
Alot of people seem to run the UR 2-piece pulley set. So far as I can tell, no one has had any problems with them. I guess it's up those guys who have them to really tell you what you need to know.
__________________
'92 SE-R, JWT POP off my old SE-R, Tein SS coilovers w/ camber plates and Whiteline FLCA bushings (woo hoo!), Silverstars, various ES bushings, and Rota C8s w/ ES100s.
The wish list: Progress rear sway and FLCAB, Active Tuning RSTB, FSTB, Crown SS lines, and Axxis Ultimates.
I remember the thread. It was Mike K (Choaderboy2) and Big Toe who were having the discussion. Lots of it flew right over my little bitty brain .
However....IIRC.....
Mike said no problem in most applications. Ie...street cars, auto-x, and even most road racing. At super high rpms over extended time, perhaps a problem.
Big Toe says don't do it ever, it's not worth the horsepower gain. Most of Big Toes experience and incredible knowledge level are attributable to his racing background. I get the feeling that he prettty much only races at 7K rpm and UP.
So there you have it, two of the biggest mechanical brainiacs on the forum....and they disagree on this one...I think.
BINGO! I win the prize. (Advanced search....threads by Bigtoe....key words "crank pulley").
Read that^^^^. LOL. See if you interpret their arguements like I did.
Further, I replaced my crank pulley because it broke. Two metal rings spinning around each other with no rubber in between. The rubber just let go due to age. Now, Bigtoe argues that the MTBF (Mean Time Before Failure) for the engine internals will be lowered if you use the UR pullies. However, I would argue with Bigtoe the the MTBF of the engine might be lowered with the UR pullies at the racetrack at 8K or whatever insane RPM's he runs for extended periods. And replacing an OEM pulley is far cheaper than replacing a race motor. However, on the street at more sane RPM's the lower MTBF of the UR crank pulley itself (vs. OEM, the UR unit can't really break into two peices because it's solid aluminum) may offset any slight lowering of the MTBF of the engine internals.
Hahahahaha....me argueing with Bigtoe about anything mechanical is pretty funny. However, I maintain that my arguement itself is sound. But it would take someone waaaaaay smarter than me to continue my one-sided debate with Bigtoe if he responds to this thread.
__________________
2004 Tahoe, stock and fully loaded.
'93 Classic - Repaired yet? No, currently being restored. Parts up to my eyeballs.
the problem is this is all theroy and experience no real test data. I doubt anyone has actually put a motor on a engine dyno with a vibration meter and percision accelerometer to measure the actual increase in vibration and where it occurs. I have the two piece pulley set on my de-t and I highly doubt it will cause any failure. I also don't run around at 7000rpm and above for extended periods. I have all the test equipment to measure this except access to a engine dyno.
I dont know what you guys consider *extended periods of time* but Ive had my UR crank/wp set on for well over 100,000 miles with absolutely no problems. The car has seen a number of track days and autocross events, including daily trips to 7000+ rpms.
I dont know what you guys consider *extended periods of time* but Ive had my UR crank/wp set on for well over 100,000 miles with absolutely no problems. The car has seen a number of track days and autocross events, including daily trips to 7000+ rpms.
Take that how ever you please.
now thats what i like to hear!!
daily high revs and plenty of track time, and mucho miles to boot... thanks for the peice of mind
__________________
-Mike
1992 NX2000, 1998 Honda Civic
60' 1.997 --- 1/8mi 8.387 @ 84.15--- 1/4mi 13.095 @ 103.29 mph Click here to see my nx2000!
My 400+ whp car had pulleys, saw numerous beatings, autoX and track events. This was an eight counter weight DE crank. My four counterwight VE crank will not get a pulley, though I did equip it witha UR flywheel. The flywheel has no dampening properties.
the problem is this is all theroy and experience no real test data. I doubt anyone has actually put a motor on a engine dyno with a vibration meter and percision accelerometer to measure the actual increase in vibration and where it occurs. I have the two piece pulley set on my de-t and I highly doubt it will cause any failure. I also don't run around at 7000rpm and above for extended periods. I have all the test equipment to measure this except access to a engine dyno.
SAE Paper 971996
Experiments and Analyses of the Three-Dimensional
Vibrations of the Crankshaft and
Torsional Damper in a Four-Cylinder
In-Line High Speed Engine
It would seem that someone has. Pay US$12.00 and see the drastic effects of damper design.
It would also seem that the motives behind studies like these, the millions spent on dampers on 4 cylinders from Japan, Europe and the USA, and the experiences of people like JWT, NISMO, JUN, TODA, TRD etc, are PROVEN useless and wasteful by the expert opinions and experiences on this Forum.
Next to Coke and Heroin, I think UR has the next best product on the market. It works and we love it even if people say it's bad.
I believe that in theory, or in extreme racing, it can create a problem. But in any practicle street car there should be no issues. Has anyone actually experienced engine failure due to somthing like this?
Black '95 200sx SE-R Turbo Lowport 286whp/245wtq 12.306 @ 113.55
White '92 NX2000 All Stock.
White '92 NX2000 Automatic, stock, not moving, and FOR SALE <---- Click for Pics
Quote:
Originally Posted by BORNGEARHEAD
It's pathetic the amount of people in this country that believe all the bullsh*t being spewed out the mouths of Bush, Cheney, Rove, Rice, Snow, oil companies, lobbyists, etc.
I believe that in theory, or in extreme racing, it can create a problem. But in any practicle street car there should be no issues. Has anyone actually experienced engine failure due to somthing like this?
If you read the thread provided you will see that quite a few folks chime in on your question, including Choaderboy2, and state that they have never heard of UR pullies causing a problem.
Hey BigToe, what about my arguement a few posts up about MTBF engine vs. MTBF of the OEM/UR pulley itself? Did I make any sense whatsoever? LOL.
SAE Paper 971996
Experiments and Analyses of the Three-Dimensional
Vibrations of the Crankshaft and
Torsional Damper in a Four-Cylinder
In-Line High Speed Engine
It would seem that someone has. Pay US$12.00 and see the drastic effects of damper design.
It would also seem that the motives behind studies like these, the millions spent on dampers on 4 cylinders from Japan, Europe and the USA, and the experiences of people like JWT, NISMO, JUN, TODA, TRD etc, are PROVEN useless and wasteful by the expert opinions and experiences on this Forum.
Next to Coke and Heroin, I think UR has the next best product on the market. It works and we love it even if people say it's bad.
cool, but was this done on a sr20 motor. I want to see real test data on a sr20 not some other in line 4cyl. Also wouldn't the removal of torque dampener cause the most stress on the number one main bearing not the rod bearings which fail and are blamed on having under drive pullies. Just curious
Next to Coke and Heroin, I think UR has the next best product on the market. It works and we love it even if people say it's bad.
Id tend to agree with the theory about not having a dampner on the crank pulley, im sure the vibrations are increased and probably causing some wear, but for your average user, the car is not sustaining 7000+ RPM for extended periods of time. Unlike dedicated race cars where the entire motor virtually lives at that RPM range. Good points ***.
