Any downsides to UDP
07-11-2003, 10:47 AM
#1
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Thread Starter
Join Date: Jun 2003
Posts: 6
Any downsides to UDP
I am considering getting a lightened UDP on my Maxima. Are there any downsides to it, such as noise, reliablity, or anything? Any help would be greatly appreciated. I'm not planning on going SC anytime soon, so I'm probably going to purchase UDP's.
07-11-2003, 11:02 AM
#2
Well it COULD underdrive your water pump or alternator to the point that you fry them but I personally havn't heard of anyone with a maxima having that problem. Supposedly RVM pulleys have had problems with the crank seal leaking or something of that nature, if i recall correctly. UR pulleys i havent heard of any problems with.
07-11-2003, 11:15 AM
#7
Senior Member
Join Date: Jan 2002
Posts: 187
Originally posted by 95emeraldgxe
if you like your A/C or you like to play your music loud dont get one
if you like your A/C or you like to play your music loud dont get one
-Sean
07-11-2003, 01:47 PM
#8
Originally posted by 95emeraldgxe
if you like your A/C or you like to play your music loud dont get one
if you like your A/C or you like to play your music loud dont get one
You're a/c will still be cold. But maybe a tiny bit less then before
07-11-2003, 02:01 PM
#9
Originally posted by SprintMax
well if you don't mind spending $150 for 0 hp and 1 hour worth of labor.. then i would say their is really no down side to it
well if you don't mind spending $150 for 0 hp and 1 hour worth of labor.. then i would say their is really no down side to it
You'll barely feel any performance gains with the pulley. SLIGHTLY less lag off the line, but nothing drastic.I do know that DaThrillr dyno'd the RVM pulley and got a max gain of 6hp at the wheels. There was a huge thread about this a few months ago, I think he posted the dyno chart as well.
07-11-2003, 11:03 PM
#12
Senior Member
Join Date: Oct 2002
Posts: 368
The overall benefit of the lightweight UDP is that it saves wear and tear on your engine by spooling/revving faster due to the lighter weight than the stock flywheel.
From what I know of them you don't necessarily gain any hp, just the added benefit of faster revving engine and longer lasting as I stated earlier.
From what I know of them you don't necessarily gain any hp, just the added benefit of faster revving engine and longer lasting as I stated earlier.
07-11-2003, 11:58 PM
#15
Originally posted by BadKarma99-4spd
so which one is the ONE to get? also how much were the belts?
thanks
so which one is the ONE to get? also how much were the belts?
thanks
-Tony
07-12-2003, 12:11 AM
#17
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Join Date: Dec 2000
Posts: 253
07-12-2003, 12:28 AM
#18
Originally posted by MaxVQ
I was going to get a UDP until I read this:
http://www.dinanbmw.com/html/danger_...er_pulleys.htm
I was going to get a UDP until I read this:
http://www.dinanbmw.com/html/danger_...er_pulleys.htm
07-12-2003, 12:31 AM
#19
Supporting Maxima.org Member
Join Date: Feb 2001
Posts: 621
Originally posted by MaxVQ
I was going to get a UDP until I read this:
http://www.dinanbmw.com/html/danger_...er_pulleys.htm
I was going to get a UDP until I read this:
http://www.dinanbmw.com/html/danger_...er_pulleys.htm
Is your maxima a BMW? no
Has anyone EVER ran into any serious problems with a UDP in their maxima? no
07-12-2003, 11:08 AM
#20
Member
Join Date: Dec 2000
Posts: 253
Originally posted by araffio
Last time I checked, this is a Maxima board and we all drive Maximas, not BMWs. That article relates specifically to BMW engines...
Last time I checked, this is a Maxima board and we all drive Maximas, not BMWs. That article relates specifically to BMW engines...
I am talking about harmonics of the crankshaft. It does not matter who makes the engine, or even the layout (I6, V6) the engine operates on the exact same principals.
With that in mind, if the gains were so easy to get, with out any harm, why wouldn't Nissan shave ~4 pounds off the crank pulley? I think there is a VERY GOOD reason why Nissan designed the crank pulley to weigh what it does.
Who would connect a bearing failure (or something of that nature) to a UDP. No one.
If you lease your car, who cares. You won't have to deal with any long term problems. If you own your car, and you want to keep it a long time is it worth it for 4-5 HP?
![][ 35's Avatar](data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 50 50'><circle class='avatar-circle-default' fill='%23915f9f' cx='25px' cy='25px' r='20px'></circle><text class='avatar-text-default' x='49%' y='53%' fill='white' text-anchor='middle' alignment-baseline='middle'>]</text></svg>)
07-12-2003, 12:03 PM
#22
Not DAVEB the parts guy
Join Date: Aug 2000
Posts: 8,555
Originally posted by MaxVQ
Let me try again:
I am talking about harmonics of the crankshaft. It does not matter who makes the engine, or even the layout (I6, V6) the engine operates on the exact same principals.
With that in mind, if the gains were so easy to get, with out any harm, why wouldn't Nissan shave ~4 pounds off the crank pulley? I think there is a VERY GOOD reason why Nissan designed the crank pulley to weigh what it does.
Who would connect a bearing failure (or something of that nature) to a UDP. No one.
If you lease your car, who cares. You won't have to deal with any long term problems. If you own your car, and you want to keep it a long time is it worth it for 4-5 HP?
Let me try again:
I am talking about harmonics of the crankshaft. It does not matter who makes the engine, or even the layout (I6, V6) the engine operates on the exact same principals.
With that in mind, if the gains were so easy to get, with out any harm, why wouldn't Nissan shave ~4 pounds off the crank pulley? I think there is a VERY GOOD reason why Nissan designed the crank pulley to weigh what it does.
Who would connect a bearing failure (or something of that nature) to a UDP. No one.
If you lease your car, who cares. You won't have to deal with any long term problems. If you own your car, and you want to keep it a long time is it worth it for 4-5 HP?
MaxVQ, I was of the same opinion as yourself concerning UDPs until I did further research into the UDPs and the VQ. I found out the VQ DOES NOT have a harmonic balancer as the crank pulley. The crank pulley is simply that, a crank pulley. It does nothing to quell harmonic frequencies of the crank. In a nutshell, the VQ is internally balanced thanks to forged, hydro-cut, and knife-edged crank. I should note that the VE/VG are NOT balanced and DO have harmonic balancers. DO NOT add UDPs to these motors.
The I6 motors in the BMW are NOT internally balanced and the crank pulley also serves as a balancer therefore it would not be wise to add any sort of non-harmonic balancer.
To answer your question as to why Nissan made the pulley rather heavy, it is to keep up the momentum of the motor during shifts. With the light UDP, the VQ has the tendency to loose revs quicker between shifts which can make it hard to engage gears as smoothly.
You're definately free to do what you want since it's your car, but there are gains with the UDP. Contrary to what Sprint says, I saw 5 fwhp/fwtq from 3000-6500rpms on the dyno and an average .1 and 1mph gain in the 1/4.
Dave
07-12-2003, 12:09 PM
#23
ok, well then how long has everyone had their pulleys for? i for one plan on driving my maxima until it explodes whether from something i did or from being too old.
thanks for the belt price info
thanks for the belt price info
07-12-2003, 12:17 PM
#24
Member
Join Date: Dec 2000
Posts: 253
Originally posted by Dave B
MaxVQ, I was of the same opinion as yourself concerning UDPs until I did further research into the UDPs and the VQ. I found out the VQ DOES NOT have a harmonic balancer as the crank pulley. The crank pulley is simply that, a crank pulley. It does nothing to quell harmonic frequencies of the crank. In a nutshell, the VQ is internally balanced thanks to forged, hydro-cut, and knife-edged crank. I should note that the VE/VG are NOT balanced and DO have harmonic balancers. DO NOT add UDPs to these motors.
To answer your question as to why Nissan made the pulley rather heavy, it is to keep up the momentum of the motor during shifts. With the light UDP, the VQ has the tendency to loose revs quicker between shifts which can make it hard to engage gears as smoothly.
You're definately free to do what you want since it's your car, but there are gains with the UDP. Contrary to what Sprint says, I saw 5 fwhp/fwtq from 3000-6500rpms on the dyno and an average .1 and 1mph gain in the 1/4.
Dave
MaxVQ, I was of the same opinion as yourself concerning UDPs until I did further research into the UDPs and the VQ. I found out the VQ DOES NOT have a harmonic balancer as the crank pulley. The crank pulley is simply that, a crank pulley. It does nothing to quell harmonic frequencies of the crank. In a nutshell, the VQ is internally balanced thanks to forged, hydro-cut, and knife-edged crank. I should note that the VE/VG are NOT balanced and DO have harmonic balancers. DO NOT add UDPs to these motors.
To answer your question as to why Nissan made the pulley rather heavy, it is to keep up the momentum of the motor during shifts. With the light UDP, the VQ has the tendency to loose revs quicker between shifts which can make it hard to engage gears as smoothly.
You're definately free to do what you want since it's your car, but there are gains with the UDP. Contrary to what Sprint says, I saw 5 fwhp/fwtq from 3000-6500rpms on the dyno and an average .1 and 1mph gain in the 1/4.
Dave
Thanks for the insight.
07-12-2003, 04:04 PM
#25
Not DAVEB the parts guy
Join Date: Aug 2000
Posts: 8,555
Originally posted by BadKarma99-4spd
ok, well then how long has everyone had their pulleys for? i for one plan on driving my maxima until it explodes whether from something i did or from being too old.
thanks for the belt price info
ok, well then how long has everyone had their pulleys for? i for one plan on driving my maxima until it explodes whether from something i did or from being too old.
thanks for the belt price info
Dave
07-12-2003, 05:10 PM
#27
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Posts: n/a
Originally posted by Dave B
MaxVQ, I was of the same opinion as yourself concerning UDPs until I did further research into the UDPs and the VQ. I found out the VQ DOES NOT have a harmonic balancer as the crank pulley. The crank pulley is simply that, a crank pulley. It does nothing to quell harmonic frequencies of the crank. In a nutshell, the VQ is internally balanced thanks to forged, hydro-cut, and knife-edged crank. I should note that the VE/VG are NOT balanced and DO have harmonic balancers. DO NOT add UDPs to these motors.
The I6 motors in the BMW are NOT internally balanced and the crank pulley also serves as a balancer therefore it would not be wise to add any sort of non-harmonic balancer.
To answer your question as to why Nissan made the pulley rather heavy, it is to keep up the momentum of the motor during shifts. With the light UDP, the VQ has the tendency to loose revs quicker between shifts which can make it hard to engage gears as smoothly.
You're definately free to do what you want since it's your car, but there are gains with the UDP. Contrary to what Sprint says, I saw 5 fwhp/fwtq from 3000-6500rpms on the dyno and an average .1 and 1mph gain in the 1/4.
Dave
MaxVQ, I was of the same opinion as yourself concerning UDPs until I did further research into the UDPs and the VQ. I found out the VQ DOES NOT have a harmonic balancer as the crank pulley. The crank pulley is simply that, a crank pulley. It does nothing to quell harmonic frequencies of the crank. In a nutshell, the VQ is internally balanced thanks to forged, hydro-cut, and knife-edged crank. I should note that the VE/VG are NOT balanced and DO have harmonic balancers. DO NOT add UDPs to these motors.
The I6 motors in the BMW are NOT internally balanced and the crank pulley also serves as a balancer therefore it would not be wise to add any sort of non-harmonic balancer.
To answer your question as to why Nissan made the pulley rather heavy, it is to keep up the momentum of the motor during shifts. With the light UDP, the VQ has the tendency to loose revs quicker between shifts which can make it hard to engage gears as smoothly.
You're definately free to do what you want since it's your car, but there are gains with the UDP. Contrary to what Sprint says, I saw 5 fwhp/fwtq from 3000-6500rpms on the dyno and an average .1 and 1mph gain in the 1/4.
Dave
There a LOTS of VE owners with UDP's and the gain is .10-.20 easily.
Calm down buddy.
07-12-2003, 08:42 PM
#29
I think the screwup with the RVM UDP may have been a simple case of RVM specifiying too high a torque rating for the bolts than they were supposed to be. The RVM instruction said to use something 146 lb-ft of TQ to screw in the bolts. I checked my FSM for the stock pulley. 46 Lb-ft. Someone may have just put a one where there wasn't supposed to be, and all those pulleys failed. Shame.
DW
DW
Originally posted by ][ 35
I'm just going to comment on the RVM UDP...
They SUCK!!!!!!!!!!! if you want to spend $80 and labor for a nice paper weight......
I'm just going to comment on the RVM UDP...
They SUCK!!!!!!!!!!! if you want to spend $80 and labor for a nice paper weight......
07-12-2003, 08:50 PM
#30
Originally posted by Dave B
MaxVQ, I was of the same opinion as yourself concerning UDPs until I did further research into the UDPs and the VQ. I found out the VQ DOES NOT have a harmonic balancer as the crank pulley. The crank pulley is simply that, a crank pulley. It does nothing to quell harmonic frequencies of the crank. In a nutshell, the VQ is internally balanced thanks to forged, hydro-cut, and knife-edged crank. I should note that the VE/VG are NOT balanced and DO have harmonic balancers. DO NOT add UDPs to these motors.
Dave
MaxVQ, I was of the same opinion as yourself concerning UDPs until I did further research into the UDPs and the VQ. I found out the VQ DOES NOT have a harmonic balancer as the crank pulley. The crank pulley is simply that, a crank pulley. It does nothing to quell harmonic frequencies of the crank. In a nutshell, the VQ is internally balanced thanks to forged, hydro-cut, and knife-edged crank. I should note that the VE/VG are NOT balanced and DO have harmonic balancers. DO NOT add UDPs to these motors.
Dave
i have a 3rd gen with the VG. and i have shyed away from the udp, as i am never given a straight answer about it. or the information does not overlap. you are saying that the VG/VE motors are not internally balanced. and i have read things about that, btw. so, then, DOES the stock pulley on these engines act, then, as the harmonic balancer? is there a final answer for this?
-bonz
07-12-2003, 09:46 PM
#31
Not DAVEB the parts guy
Join Date: Aug 2000
Posts: 8,555
According to my Chilton's service manual, the VE and VG crank pulleys are indeed harmonic balancers. The VQs crank pulley is not. I would NEVER run an UDP in place of a harmonic balancer. NEVER.
dmontzsta-
Sure, they make UDPs for the VE/VG, but that doesn't mean they're safe. I don't know of any failures, but snapping a crank because of running an non-harmonic balancer UDP seems crazy to me. It's not worth the risk for a little extra power. To each his own.
Dave
dmontzsta-
Sure, they make UDPs for the VE/VG, but that doesn't mean they're safe. I don't know of any failures, but snapping a crank because of running an non-harmonic balancer UDP seems crazy to me. It's not worth the risk for a little extra power. To each his own.
Dave
07-12-2003, 09:59 PM
#32
yes, Dave B, i hear you. your advice is sort of the "last in line" for me. that is all i needed to hear further about this whole UDP issue. i have read this and that and this subject has come to a head >>> an extra 4 or 5 hp is absolutely NOT worth getting if my VG, in great shape, is going to be destroyed. absolutely not worth it. a UDP cannot be a harmonic balancer in a million years. btw, brian catts of Cattman recommends AGAINST the UDP in the 3rd gen as well. so i have heard enough. thank you so much, good sir. and happy motoring in your awesome ride. for all else who actually can get away with a UDP, in a way, i do envy you all. but i am fine no matter what. VG-to-VE VLSD 5spd tranny swap, lightweight fidanza flywheel/exedy stage one, here i come.
07-12-2003, 10:55 PM
#33
Originally posted by Dave B
To answer your question as to why Nissan made the pulley rather heavy, it is to keep up the momentum of the motor during shifts. With the light UDP, the VQ has the tendency to loose revs quicker between shifts which can make it hard to engage gears as smoothly.
To answer your question as to why Nissan made the pulley rather heavy, it is to keep up the momentum of the motor during shifts. With the light UDP, the VQ has the tendency to loose revs quicker between shifts which can make it hard to engage gears as smoothly.
07-13-2003, 08:27 AM
#35
I thought that was the purpose of the heavy OEM flywheel, not the OEM drive pulley.
DW
DW
Originally posted by Dave B
. . . To answer your question as to why Nissan made the pulley rather heavy, it is to keep up the momentum of the motor during shifts. With the light UDP, the VQ has the tendency to loose revs quicker between shifts which can make it hard to engage gears as smoothly.
Dave
. . . To answer your question as to why Nissan made the pulley rather heavy, it is to keep up the momentum of the motor during shifts. With the light UDP, the VQ has the tendency to loose revs quicker between shifts which can make it hard to engage gears as smoothly.
Dave
07-13-2003, 08:39 AM
#36
Guest
Posts: n/a
Originally posted by Dave B
According to my Chilton's service manual, the VE and VG crank pulleys are indeed harmonic balancers. The VQs crank pulley is not. I would NEVER run an UDP in place of a harmonic balancer. NEVER.
dmontzsta-
Sure, they make UDPs for the VE/VG, but that doesn't mean they're safe. I don't know of any failures, but snapping a crank because of running an non-harmonic balancer UDP seems crazy to me. It's not worth the risk for a little extra power. To each his own.
Dave
According to my Chilton's service manual, the VE and VG crank pulleys are indeed harmonic balancers. The VQs crank pulley is not. I would NEVER run an UDP in place of a harmonic balancer. NEVER.
dmontzsta-
Sure, they make UDPs for the VE/VG, but that doesn't mean they're safe. I don't know of any failures, but snapping a crank because of running an non-harmonic balancer UDP seems crazy to me. It's not worth the risk for a little extra power. To each his own.
Dave
07-13-2003, 10:07 AM
#38
Not DAVEB the parts guy
Join Date: Aug 2000
Posts: 8,555
Originally posted by dmontzsta
hmmm...this is interesting. I am looking in the FSM and do not see anything about a harmonic balancer. Where did you hear about it?
hmmm...this is interesting. I am looking in the FSM and do not see anything about a harmonic balancer. Where did you hear about it?
Dave
07-13-2003, 10:09 AM
#39
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Posts: n/a
Originally posted by Dave B
I'm going by what I read in my Chilton's manual since it uses many of Nissan's FSM diagrams. Chilton's makes many references to the VE/VG pulley as being a "damper" whereas the VQ's pulley is referenced as a "pulley". Damper is usually another way of saying balancer. My 1996 FSM referes to the VQ pulley as a pulley only.
Dave
I'm going by what I read in my Chilton's manual since it uses many of Nissan's FSM diagrams. Chilton's makes many references to the VE/VG pulley as being a "damper" whereas the VQ's pulley is referenced as a "pulley". Damper is usually another way of saying balancer. My 1996 FSM referes to the VQ pulley as a pulley only.
Dave
