I'm trying to decide which I would like better between a 28LB Steel OR a 18LB Alum; steel is 55% heavier AND reciprocating mass.

I have NO Real World experience here.

My expectation is heavy will act similar to the stocker and normal take off from dead stop will react similar to present.

Present is LS2 with Airaid CAI and Corsa Sport on a 2006 Z51 Manual top vert. I won't go into the mill to make changes (saving that for a diff platform on the next vette). I like this fuel mileage and VERT is awesome! (t56 needs some attention / CGW shifter and custom bilsteins on order, new michelin zp's installed in July 2011, car has 23k miles.)

Less reciprocating mass suggests faster spin up and could actually be felt in powerband? Alum perhaps suggests it could be resurfaced if repairs were in order - so I have read.

Questions for those who have chosen to go lighter or heavier than stocker for similar LS2:

1. Which did you choose and why?
1a. Did change meet your expectation?
1b. Would you do same again or different again?

Please add anything else to sway my decision help me with an informed decision! THANK YOU!!!! this is fun!

 

1. I went with alum because of the lesser rotating mass. It only makes sense that the lighter mass should let the motor rev a bit happier and it did.

1a. Yes! All the negatives I heard from others were not the case for me.

1b. I went even lighter. The stock LS7 and alum fly was @47lbs and I went with an Exedy Twin plate thats @38lbs. Engine is very happy. I wont go any lighter than this though.

 

It is rotating mass, reciprocating is back and forth motion, ie your pistons and rods. The car will feel snappier but stop and go traffic gets a little tricky. The car will want to kill a lot easier as you get to the friction point of the clutch. If you are a good driver you will get used to it pretty fast and go on with your business. When my clutch goes out i'm going Aluminum.

 

I stand corrected on my terminology. (duh)... Thanks!

I appreciate the feedback greatly!

I wonder if torque feels down at low RPM's? (yeah; I suppose torque is (somewhat of) a equation of HP too but feel free to correct my thinking - I'm no auto engineer.

(zx1216 - hmmmmmmm, I'm thinking green but I liked the 2000(?) Red better) tks again!

 

You say that this is for fun? Have you considered other upgrades to your car that would more "fun"? Changing a clutch is pretty involved in these cars and isn't something that I would do for fun. If your looking for a peppier car, consider headers first. They are much easier to install.

 

I would (and have) take the aluminum over the steel. I'm a long-trim drag racer, and STILL would take aluminum over steel. That said, you likely won't feel the difference on the street.

 

I'm kinda "TWISTED" so I can have fun wrenching on my equipment. I have quite fast and smooth motorcycles that I get real thrills from. Yes I am considering Headers for the vette.

In reality I have no problems conceptually with changing the entire exhaust (UNSURE ABOUT Emissions but have a plan to understand this) other than mostly funding. I suspect my clutch has a slight wobble in the TO Bearing??? In other words it does not seem perfect. I probably need the ability to bleed the TO bearing too - but I have not worked through that either at this time! Otherwise, so far it appears headers are not cheap and I'd obviously need a pipe to get from new Headers to Corsa Sport. I'm doing research - still don't want to mangle my efficient fuel mileage nor put undue stress on the mill. To me changing the intake and exhaust should not stress the mill internals too far and could allow more overall efficiency. If the power is there - I will use it at times!!! Due to my bikes (limited $) and long term plan for platform upgrade I may not choose to spend additional funds for more power. I'd like the shifting, brakes and drivetrain perfect if at all possible though. (Brakes are in need of minor attention too - topic for later and after I get the service manual. I have time.)

WHAT Header (package) do you / does anyone recommend for LS2 and Corsa Sport? I need value per $ expended. (Please make that suggestion stupid proof too if possible. I may need to do the work myself and cannot compromise the integrity of the vehicle by doing so. I also do not want to waste our vendors time by asking questions / absorbing their time.)


BLACKCLOUD - Thanks for feedback! Potentially Not feeling a difference on the street with less flywheel weight is a huge BENEFIT in my mind.

 

When I changed my clutch, I went with all lighter components. Lightweight pressure plate and lightweight flywheel. The entire assembly was 21 lbs light than stock. I could definitely feel the engine rev faster but I have 4.10 gears so take off wasn't as big of an issue as it might be for someone with stock gearing. The peddle feel was a little tougher but I pretty much got the feel for it by the end of the 25+ mile drive home from the shop. I have no quantifiable testing to compare it to other than some spirited driving. There is one stretch of highway that I like to take some full throttle runs on when it's empty. After the clutch install, I found I was going 10mph faster than I usually do in relatively the same amount of time and distance. Like I said this is a highly inaccurate way of measuring anything, but it was something I noticed without actually trying to do anything different.

 

I bought LG street series catless headers from a vendor for less than $1100 shipped. They came with the xpipe so it will bolt directly to your exhaust. Perfect fitment and great sound and power. Got about 50-55 rwhp from headers, ported stock intake / throttle body combo and initial tune. No baseline numbers but ended at 384/390 on a mustang dyno.

 

In a light vehicle like the vette I prefer a lighter flywheel as it makes the engine snappier. It rev matches easier if you prefer rowing through the gears. The 10lbs isn't a huge difference in driveability (no need for a re-tune) and you will likely become accustomed to it after a few drives. It's takes more seat time to learn to drive a lightweight clutch set-up with an aggressive friction material.