Harmonic Balancer Questions.
Thread Starter
Intermediate
Joined: Jun 2006
Posts: 35
Likes: 3
From: Atlanta Georgia
Harmonic Balancer Questions.
Ive been reading about the balancer issues the c5 has. Ive now noticed my balancer is wobbling. I know not to drive the car cause it will explode but the question is what kind of balancer should i put on it? I most likely will do a cam upgrade so give me both senarios with and without a cam. Also is installing a cam with stock heads and intake a bad idea? Thanks for the help.
Le Mans Master
Joined: Sep 2003
Posts: 6,276
Likes: 227
From: Farmington CT
Cruise-In VII Veteran
read www.ls1howto.com , feeling motivated? the cam is another hour and $1g in parts away, add 2 hours for the spring swap, if you are a skilled wrench turner
Le Mans Master
Joined: Dec 2003
Posts: 5,561
Likes: 448
From: Atlanta metro Ga.
Do what I did, use a marginal pulley as an "excuse" to do a cam upgrade.
I went with the ASP 25% underdrive pulley, A: becuase it was *almost* as light as stock (most aftermarket units are heavier than stock), b: it underdrives both the main and A/C accessories.
Went with a very mild LPE GT2-3 cam, completly stock LS1 heads and intake, 918 springs and Ti retainers, 7.425" hardend push rods. With my B&B shorties and a Vararam, here is a clip from a previous post;
Amb. temp 76.5*, correction factor 1.03
365 HP ~ 352 TQ, to the rear wheels of course. This is w/ the bone-stock PCM tuning.
That equates to approx. FWHP (15% drivetrain loss) of
418.7 HP ~ 403.7 TQ
Now keep in mind my AFR took a huge dump right at 3500 RPM's, exactly where I should start to see gains from the new cam.
From 2000 ~ 3500 it was a perfect 13.0, then by 4000 it had dropped to 12.5, 4500 it was down to 11.8, from 5000 to 6500 somewhere around 11.5 finally ending up at 11.0.
So this rich condition on the top killed the typical "peak" you see from 5500 to 6500 on a stock car, much less one w/ a cam.
You could make a very conservative educated guess and say the fat AFR is costing at least 10RWHP.
I went with the ASP 25% underdrive pulley, A: becuase it was *almost* as light as stock (most aftermarket units are heavier than stock), b: it underdrives both the main and A/C accessories.
Went with a very mild LPE GT2-3 cam, completly stock LS1 heads and intake, 918 springs and Ti retainers, 7.425" hardend push rods. With my B&B shorties and a Vararam, here is a clip from a previous post;
Amb. temp 76.5*, correction factor 1.03
365 HP ~ 352 TQ, to the rear wheels of course. This is w/ the bone-stock PCM tuning.
That equates to approx. FWHP (15% drivetrain loss) of
418.7 HP ~ 403.7 TQ
Now keep in mind my AFR took a huge dump right at 3500 RPM's, exactly where I should start to see gains from the new cam.
From 2000 ~ 3500 it was a perfect 13.0, then by 4000 it had dropped to 12.5, 4500 it was down to 11.8, from 5000 to 6500 somewhere around 11.5 finally ending up at 11.0.
So this rich condition on the top killed the typical "peak" you see from 5500 to 6500 on a stock car, much less one w/ a cam.
You could make a very conservative educated guess and say the fat AFR is costing at least 10RWHP.
Last edited by Dan_the_C5_Man; Jun 14, 2006 at 12:52 AM.
Drifting
Joined: Dec 2005
Posts: 1,720
Likes: 3
From: East Hampton CT
My big question for everyone running 25% underdrive units is if the alternator still charges enough at idle with all accessories running, and if the AC works well in heavy traffic with lots of idling (assuming stock 750rpm idle).
I have heard horror stories of charging and AC issues with underdriven accessories.....
I'm not worried about the cam...more worried about which pulley to go with.
I have heard horror stories of charging and AC issues with underdriven accessories.....
I'm not worried about the cam...more worried about which pulley to go with.
Le Mans Master
Joined: Dec 2003
Posts: 5,561
Likes: 448
From: Atlanta metro Ga.
Originally Posted by Billdog350
My big question for everyone running 25% underdrive units is if the alternator still charges enough at idle with all accessories running, and if the AC works well in heavy traffic with lots of idling (assuming stock 750rpm idle).
I have heard horror stories of charging and AC issues with underdriven accessories.....
I'm not worried about the cam...more worried about which pulley to go with.
I have heard horror stories of charging and AC issues with underdriven accessories.....
I'm not worried about the cam...more worried about which pulley to go with.
Safety Car
Joined: Sep 2003
Posts: 3,558
Likes: 2
From: Cape Coral FL
Originally Posted by Dan_the_C5_Man
Absouletly zero issues w/ the charging or A/C systems here..
Also, with the cam you may want to bump the idle a bit. That will take care of any charge issues. Also, you will get a bit extra gas mileage from the underdrive.
Drifting
Joined: Dec 2005
Posts: 1,720
Likes: 3
From: East Hampton CT
Dan, seeing that you're in Hotlanta....your statement goes a long way. How long have you had your setup and has there EVER been a time where the ac or charging wasn't sufficient? Also, what's your idle set at?
Melting Slicks
Joined: Aug 1999
Posts: 3,452
Likes: 3
From: Spring, TX
Check my sig. I did this swap using as ASP pulley. I have had no problems with the electrics or the A/C. That is until now the compressor died but hell the car has over 120K on it. Doubt it was the pulley. It has been on for two years.
Do this soon. My balancer failed and it took out the front engine cover and the front of the oil pan. Real mess. Did the cam swap and repaired it all myself. Tough job but fun.
Do this soon. My balancer failed and it took out the front engine cover and the front of the oil pan. Real mess. Did the cam swap and repaired it all myself. Tough job but fun.
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Le Mans Master
Joined: Dec 2003
Posts: 5,561
Likes: 448
From: Atlanta metro Ga.
Originally Posted by Billdog350
Dan, seeing that you're in Hotlanta....your statement goes a long way. How long have you had your setup and has there EVER been a time where the ac or charging wasn't sufficient? Also, what's your idle set at?
A/C and charging were no different than before the mod. Now I will say that (I believe) A4 cars stock idle is set lower, so that *might* present an issue. Running this set-up for over a year now.