Are there any side effects to raising my stock A4 idle to 650 for a 25% crank pulley?
09-29-2005, 08:48 PM
#1
TECH Resident
Thread Starter
Join Date: Jan 2002
Location: Picatinny Arsenal, NJ
Posts: 896
Likes: 0
Received 0 Likes
on
0 Posts
Are there any side effects to raising my stock A4 idle to 800 for a 25% crank pulley? I've read that the stock idle for some LS1 cars with the A4 is not high enough for a 25% crank pulley as those cars with the stock idle usually experience charging problems and have a hard time just trying to park. I've also read that there are two ways around this--either use an overdrive alternator pulley which will negate some of the gains of the crank underdrive or simply raise the stock 550 idle to 650-675. Is there a side effect to raising the idle by that much? What would be the preferred method of avoiding any charging problems? Thanks in advance for the info.
Last edited by damon_Z; 10-03-2005 at 05:09 PM.
09-29-2005, 10:27 PM
#2
LS1Tech Administrator
iTrader: (3)
Join Date: Nov 2001
Location: Schiller Park, IL Member: #317
Posts: 32,019
Likes: 0
Received 1,467 Likes
on
1,058 Posts
Stock idle rpm for A4 LS1 is 550rpm in gear/650rpm in park/neutral.
No problem raising the idle with tuning. I had my '00 WS6 idling at 800/850rpm even before I put the cam in. The only thing is that the higher the idle the more you'll feel the car trying to "pull" through the brakes when you're stopping. This is mostly only noticable with the stock stall TC. As you go bigger (looser) this condition will vanish. But at 650 I doubt you'd feel anything anyway.
No problem raising the idle with tuning. I had my '00 WS6 idling at 800/850rpm even before I put the cam in. The only thing is that the higher the idle the more you'll feel the car trying to "pull" through the brakes when you're stopping. This is mostly only noticable with the stock stall TC. As you go bigger (looser) this condition will vanish. But at 650 I doubt you'd feel anything anyway.
09-30-2005, 06:26 PM
#4
TECH Resident
Thread Starter
Join Date: Jan 2002
Location: Picatinny Arsenal, NJ
Posts: 896
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Blacker
I raised mine by 100 rpm to keep the lights from dimming a tad at night. No side effects of doing this.
09-30-2005, 06:34 PM
#5
TECH Resident
Thread Starter
Join Date: Jan 2002
Location: Picatinny Arsenal, NJ
Posts: 896
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by RPM WS6
Stock idle rpm for A4 LS1 is 550rpm in gear/650rpm in park/neutral.
No problem raising the idle with tuning. I had my '00 WS6 idling at 800/850rpm even before I put the cam in. The only thing is that the higher the idle the more you'll feel the car trying to "pull" through the brakes when you're stopping. This is mostly only noticable with the stock stall TC. As you go bigger (looser) this condition will vanish. But at 650 I doubt you'd feel anything anyway.
No problem raising the idle with tuning. I had my '00 WS6 idling at 800/850rpm even before I put the cam in. The only thing is that the higher the idle the more you'll feel the car trying to "pull" through the brakes when you're stopping. This is mostly only noticable with the stock stall TC. As you go bigger (looser) this condition will vanish. But at 650 I doubt you'd feel anything anyway.
09-30-2005, 07:16 PM
#6
TECH Resident
iTrader: (1)
Join Date: May 2004
Location: Tree-Hugging, Bug eating CALI'
Posts: 848
Likes: 0
Received 0 Likes
on
0 Posts
I have mine at 750 with no problems. With the stall in there, sometimes the car wants to die if I stop quickly, with the A/C on. Yeah, if you have the stock converter, it will push the car more, but not so much that it is a pain. With a stall, you can' t hardly tell 
Trending Topics
10-07-2005, 09:38 PM
#12
TECH Resident
Thread Starter
Join Date: Jan 2002
Location: Picatinny Arsenal, NJ
Posts: 896
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by WILWAXU
Why not get a overdrive altenator pulley?
10-07-2005, 10:18 PM
#13
Increasing the idle isn't going to negatively affect anything. Just give in an additional 100-150 rpm's and be done with it. The overdrive pulley is not necessary and will decrease the gains of the underdrive crank pulley. The additional 100-150 rpm is not noticeable. I have mine up to 850 rpm with the cam and no problems with that.
