how about underdrive pulleys?
03-01-2007, 03:12 PM
#1
Launching!
Thread Starter
Join Date: Feb 2006
Location: South Carolina
Posts: 272
Likes: 0
Received 0 Likes
on
0 Posts
how about underdrive pulleys? how many of you guys use underdrive pulleys? i saw the set of March Serpentine Pulleys in the summit catalog for just over 100 dollars? would i get a fair gain for the money and time it would take? thanks
03-01-2007, 05:23 PM
#3
i got a underdrive, no balanced engine but my car's rpms well lets just say foot goes down im at like 6.4k already shifting... they said going from a 48-52 mm TB will kinda kill that alittle bit but my car needs to breath go for it man
hey merv u know how to tell what % underdrive its a little ****** but i dunno what percent or whatever
hey merv u know how to tell what % underdrive its a little ****** but i dunno what percent or whatever
03-02-2007, 11:57 PM
#4
TECH Apprentice
iTrader: (6)
Join Date: Jun 2006
Location: Quebec,Canada
Posts: 373
Likes: 0
Received 0 Likes
on
0 Posts
Personally, I wouldn't bother with an UD pulley unless it is the ASP brand since its the only one with an incorporated damper.
So its an 23% underdrive with the damper for the crank and it your sytem fully charge at only 800rpm.
All the other one are solid pulley that will not absorb vibration so it basiclly sucks...
You have also piggyback one that bolts over your stock crank damper.This will increase the weights on the end of the crank and will not help you at all.
Even if your engine is neutral balance you still wanna have the damper to absorb the small vibration that will kill your bearings
You wont see huge gain because our water pump are gear driven instead of belt driven.But you will see that the throttle response and rpm will come quicker.
So its an 23% underdrive with the damper for the crank and it your sytem fully charge at only 800rpm.
All the other one are solid pulley that will not absorb vibration so it basiclly sucks...
You have also piggyback one that bolts over your stock crank damper.This will increase the weights on the end of the crank and will not help you at all.
Even if your engine is neutral balance you still wanna have the damper to absorb the small vibration that will kill your bearings
You wont see huge gain because our water pump are gear driven instead of belt driven.But you will see that the throttle response and rpm will come quicker.
03-03-2007, 12:43 PM
#6
ASP???
ATI I know about and they offer UD dampers.
Underdrive pullies are best on vehicles with belt driven water pumps.
On an LT1 the most useful they can be is for road racers where it slows accessories which helps keep the PS system happy, good idea if that is your usage.
In the future I will likely get an STI damper in a UD size but it will be the damper I am after and the UD just a SLIGHT side benifit.
I know someone who put a UD pulley on his car but then runs dual batteries for his very modest stereo, as is needs no electrical upgrade unless you compromise the stock system with an UD crank pulley
.
I see that as pretty much the same level of reasoning ability that the rest of the UD lovers exhibit.
Like I said with the road racing thing they can serve some purposes but as an early bolton on a stockish car I see them as a waste. With the WP not driven by the belt the load on out belt is much lower than that of other cars so the potential for gain is much lower than other cars.
ATI I know about and they offer UD dampers.
Underdrive pullies are best on vehicles with belt driven water pumps.
On an LT1 the most useful they can be is for road racers where it slows accessories which helps keep the PS system happy, good idea if that is your usage.
In the future I will likely get an STI damper in a UD size but it will be the damper I am after and the UD just a SLIGHT side benifit.
I know someone who put a UD pulley on his car but then runs dual batteries for his very modest stereo, as is needs no electrical upgrade unless you compromise the stock system with an UD crank pulley
.I see that as pretty much the same level of reasoning ability that the rest of the UD lovers exhibit.
Like I said with the road racing thing they can serve some purposes but as an early bolton on a stockish car I see them as a waste. With the WP not driven by the belt the load on out belt is much lower than that of other cars so the potential for gain is much lower than other cars.
03-03-2007, 02:54 PM
#7
TECH Addict
iTrader: (9)
Join Date: Nov 2004
Location: Kzoo, MI
Posts: 2,289
Likes: 0
Received 0 Likes
on
0 Posts
I mostly wanted it to slow the PS pump down on the long highway trips.
Dwayne ASP makes an integrated damper/underdrive pulley. I had ask Dmitry about them, and he said they stopped making the b-car one 4yrs ago or so. He said the F-body assembly (that they currently sell) is different.
Dwayne ASP makes an integrated damper/underdrive pulley. I had ask Dmitry about them, and he said they stopped making the b-car one 4yrs ago or so. He said the F-body assembly (that they currently sell) is different.
