varkwso

What is recommended for a harmonic balancer replacement for a LS1/6/2? I am pretty sure I want a ARP replacement bolt.

I have a bad one on a C5 - any tips on replacing one?

thanks...

trackboss

ATI.
Use a GM/Chrysler puller and to install you need a piece of 16mmx2.0 all thread along with some nuts. Normal installer will not work as the threads in the LS cranks are very deep. After it's installed have someone step on the brakes and transmission in 4th gear to help prevent motor from spinning while you torque the bolt. Use assembly lube or silicone under the bolt head and washer.

Z11409

http://forums.corvetteforum.com/c5-t...ving-bolt.html

drivinhard

Jeff whatever one you get, make sure you get a pulley with a 3/16 key slot, and get the ATI pin kit and pin that thing. No need for the "torque bolt to 7 million ft/lbs and then stretch it another 1/4 mile" method. I am not a fan of the "bolt torque smooth bore interference fit" on the LS engines.

BTW I've got a pin kit fixture (and maybe even a spare pin or 2) and a crank installer tool. Can bring it to RA next weekend if you want to borrow it.

davidfarmer

ATI worked with GM racing to develop theres. I'd go with 10% underdrive aluminum, but you MUST key it as the aluminum can "grow" over time, especially if you ever remove/reinstall.

I've run these on several engines. You will likely need a fixed belt tensioner to keep the belt from flying off.

varkwso

can you pin it while it is in the car?


please bring to RA if possible - how did the trans swap go this weekend?

varkwso

I have one in the garage (not sure of why I have it) wondered why anyone installed them..

kmagvette

I did this a while ago as part of a timing chain change. Per suggestions from this forum I went with the ATI 10% underdrive and pinned the crank while I was at it. I drilled the crank from under the car on jack stands.

Everything was pretty easy, for a first-time like myself, if you don't force things. I had to drop the pan to heli-coil the temperature sensor block so I dropped the entire front cradle...so I missed out on the wrestling match with the power steering rack, my loss I guess.

drivinhard

yeah you can pin it in the car


Swap went good. Jason got to peek under the M12's skirt (case) and I found a way to ensure that I can beat him in paralyzing his car in the below fashion

davidfarmer

pinning is easy, just drill a hole in the snout of the crank. I have a "kit" as well, but you can literally just drill a hole and it will be fine (you need it as perpendicular to the crank as possible. I just get iron rod from Lowes and cut it to length.

As with anything on this part of the car, getting the steering rack out of the way is the hard part

96CollectorSport

ATI has a couple of different options 10% or 25% underdrive they also have different hardness of rubber. For a track day/road race car you want the 10% UD with the softer rubber. You will also have to rebuild the balancer every year or two. And as stated above you will want to pin the crank. With all of the extra maintenance you may just want to stick with stock. Just my opinion.
Joel

thehammer69

Fluidamper makes another good one that you never have to rebuild due to hardening rubber.

96CollectorSport

Not trying to shoot down recommendations but Katech uses ATI and if you look around on LS1Tech there are timing chain failures due to dampeners that are not up to the task at the race track.
This is information that I wish I had a few years ago.

varkwso

Went with ATI and ARP bolt. They told me 5 years (I do ~42 track days a year - should make ~50,000 before rebuild needed).

drivinhard

do you need the pin fixture at RA this weekend or do you have it done already?

varkwso

I was planning on borrowing yours...

I am bringing some body parts for your garage art from Mikes car also...

drivinhard

I'll bring it over with me sat.

varkwso

Thanks! I will be doing the repair when I get back from Knoxville on Friday...

varkwso

After you pin damper onto the crank (or in the case of my ATI setup the "collar") - how do you get it off again since at some point I will be back into the engine?

stairman

you pin it straight in from the front and it slides on and off like a key.
the trick is lining it back up when you reinstall it.