Summit underdrive pully?
#1
On The Tree
Thread Starter
iTrader: (14)
Join Date: Mar 2006
Location: Rochester, NY
Posts: 113
Likes: 0
Received 0 Likes
on
0 Posts
Summit underdrive pully?
just wondering if anyone has used or heard anything about the summit brand underdrive balancer? here's a link.
http://store.summitracing.com/partde...DC2502&FROM=MG
http://store.summitracing.com/partde...DC2502&FROM=MG
Trending Topics
#8
TECH Addict
iTrader: (1)
An underdrive is a no brainer. If GM wanted to reduce the parasitic loads on the engine they would come from the factory with one. Not only that but, all those devices last a lot longer because they spin 25% slower throughout their lifetime. Why do water pumps and A/C compressors fail a lot of times? The bearings wear out. With an underdrive the bearings are going to live longer. Your fuel mileage goes up and wasted horsepower is directed to the wheels instead of out the tailpipe. I looked up this item on the Summit website after seeing this post. There are two available. One has a 6.750 dia. while the other is 6.140 even though they are both rated at 25% underdrvie. We know that can't be true. I know which one I'm buying. 5/8" isn't a whole lot, but it might give an extra 5%. Every little bit helps.
#9
TECH Senior Member
iTrader: (8)
Anybody have any experince with March underdrive pulleys? Never seen anyone on the boards list them in their mods but they say they are fluid dampened which I never heard anyone else claim. One of the little talked about about functions of a crank pulley(actually harmonic balancer) is to absorb some of the vibration of the crankshaft and give longer crank/bearing life. I have heard this is actually very critical on some engines (certain Hondas for instance) and they are tuned by the manufacterer and should not be changed. I know LS1's are internally balanced so that is not a factor but am wondering if there is any downside on our motors other than the obvious. I need to know if there are any "pulley/ balancer gurus" to answer this out there before my H/C swap next month? Now if I can only decide on a H/C combo too! lol