I guess the camaor lt1 engine ar external blanaced like our vettes. That must mean the camaro FW has the same balance offset like the ZF fw ? or??

 

thats a good question... and I am hoping one of the machinest types chimes in. This is where my knowledge gets fuzzy and confused.

:lurk:

 

yes, but all the combinations, even from vette to vette and camaro to camaro, are slightly different from each other. some years use bolts in various holes to fine tune the balance, such that you can just transfer those over to the replacement flywheel. i see some post their flywheels even had a bolt-on weight, although all the ones i've seen have it cast into place.

fwiw, though, i bolted a camaro flywheel onto my vette with no modifications, and it was smooth. i know some aren't so lucky.

the bottom line, though, is that the engine balance spec is the same for all LTx engines. they're just not as rigorously toleranced such that you can't expect a perfectly smooth engine if you start swapping parts around.

-michael

 

fish, I think you have been "fishing" :lol: around this flywheel/clutch subject for a while if I'm not mistaken. This is an area that does NOT invite experimentation. Having been down this road with "experts" who cannot agree on what works, and in addition, MUCH well intended but nonetheless MIS-information posted on the CF, my recommendation is to simply bite the bullet and buy a matched FW/clutch/T-O bearing set up from a company like McCloed. You will be happy with the results, and you will only have to do the job ONCE. (or only pay to have it done once.) It's your call. Just an opinion. :cheers:

 

That's all well and good... but it doesn't solve the problem of the flywheel being matched back to the engine... if the new assembly is out of balance, in relationship to the engine, then there the potential for a vibration.

 

yes i have been fishing, but havent really got any final answers yet on this issue.
If I get a complete kit from McLeaod, i should face the same probleme like if i use a camaro fw. Both just use the same offset that GM used to balance our engines. And do NOT use fine adjusments like the orginial dualmass ( the tiny wieghts that you plug in to the back of the FW to fineadjust the offset ).
I know many people that change there dualss to a new one and DONT use "fine tune" wieghts with no probleme. But then again, they dont revve the engine abow 5500.
So untill I get a final solution to this issue I will keep posting this question all over the i-net :) hehe

 

What happen to me is this:
I had an 89 L98. It was externally balanced (stock)
I put a camaro FW that was neutral balanced. The motor was shaking like crazy.
So I took it back out and took it and the original DM FW to a machine shop with a balancing machine. They added weight(welded it on) to the camaro FW. Then the motor was fine and smooth after that.


I have since changed the motor to something else that is fully internally balanced and I took off the welded on weight of the camaro FW.

 

exactly. a friend in austin installed a set with a single-mass Al flywheel, and it vibrated. i forget who's it was.

my fidanza came with 2 different weights and a note saying the balance should be checked prior to installing.

i'm not sure why gm couldn't keep the tolerances tight like ford with the 5.0L. those engines and flywheels are all so close than you can interchange at will.

-michael

 

A internal balanced camaro FW? Where did you get that?
This balance thing is so annoying.
How the hell do you bild a extern balanced stroker engine with the stock dual mass FW without going throu all this bull***it? And if you build a internal balanced stroker you still need to get the dualmass fW zero blanaced..
arghhhhh..

:nonod:

 

keep in mind, too, for if/when you build that stroker: the stock d-m flywheel has springs and grease inside. if they try to neutral balance it and drill too far, you're left with scrap metal. this happened to me and a few others online.

-michael

 

L98's are balanced differently.
Just take whatever flywheel you are buying and the one you already have in to a GOOD machine shop. Have them balance the new one to match the old one. I converted to a F-body wheel. Had them deck to match (0.085") and balance match. cost $150, a bit much, but it was worth it. I have no vibrations. Have them to make sure your new one is the same thickness/deck height as well.


[Modified by y5e06, 3:59 PM 2/26/2004]

 

"L98's are balanced differently?"
Yes and no.

All the L98 that came out from the GM factory has the same basic balance offset . And then uses the small wieghts to fine tune it. If that would not be the case, it would be impossible to get a new FW from gm. Then you would need to rebalance the hole rotating assembly every time you get a new fw.




[Modified by devilfish, 11:12 PM 2/26/2004]

 

"That's all well and good... but it doesn't solve the problem of the flywheel being matched back to the engine... if the new assembly is out of balance, in relationship to the engine, then there the potential for a vibration."-- bogus

"Then you would need to rebalance the hole rotating assembly every time you get a new fw." --devilfish

IMO, neither of you guys want to get it. Whatever FW you get to replace what you currently have, presuming that your existing setup did not cause vibration, all you have to do is as noted and illustrated above. If you match the counterbalance of the old to the new, you're good to go. You would only neutral balance your FW if you had your motor rebuilt and totally 100% internally balanced.
Fish, the reason I suggested not re-inventing the wheel was not to in any way admonish you, it was to help you avoid the BS I went through. That's why I suggested a known, matched set from a prominent manufacturer. My engine builder tried an unknown combo at MY expense. He shared in it jsut a little when he had to do a second R&R at his expense because the first FW was .100" too thick. The THIRD R&R and second full FW and clutch assembly was at MY expense when the POS Spec unit exploded.
FYI only. It's your car.:cheers:

 

I appreciate all the info i get here.

My question really comes down to two questions. This is what bugs me, just tell me if I think right or not on this one :) heh

If you get a internal balanced rotating assembly you must zero balance your dualmass FW, and that involves some danger if your machine shop dont know what they are dealing with. If they drill to deep in the FW they can damage the the FW and cause a leak on the material between the two masses? Right?

If you get a external balanced rotating assembly you must balance the kit with YOUR balancer and YOUR FW. And the same goes here, if your machine shop dont know what they are dealing with, they can damage the FW.
And if you sometime get a new FW you must transfer the balance to the new FW.

Can that sum it up?

 

y5e06-If I use a f-body flywheel just have .085 machined off the face? also can I use my existing clutch p/p t/o bearing.(centerforce d/f 3000 miles old).
I am building another engine to replace the the old one and would like to have ready to r/r in one weekend without worrying about balancing with original flywheel.thanks.

 

I think so.

If you want to externally balanced engine, take your crank, front pulley and hub (I'm pretty sure these are neutral but take them anyway), flywheel, and bobweight (or let them figure it) to the machine shop and do whatever you have to do to the flywheel to get it balanced. Then if you ever have to change flywheels in the future, just match balance them and you will be fine.

If your internals are neutral, then neutral balance the flywheel. Three independantely neutral balanced objects (pulley/internals/flywheel) bolted together gives you a neutral balanced assembly.

My tip on neutral balancing the dual-mass it to not drill. Have the shop put the flywheel on a mill and remove the offset mass on the engine side. This will get you in the ballpark where you can then drill small holes around the perimeter pointing toward the center to get it neutral. This will keep you away from the flywheel internals.

 

Others who have done the conversion say 0.090". I took both my wheels in and they measured them. To match they needed to take off 0.085". You'd probably be doing pretty good if you went with 0.085". but if you are doing the job yourself and have a 2nd car then just take both in so the can get the thickness correct and a good balance. FWIW the machine shop only had to remove a small amount of material to get the balances matched. Most likely would have been ok w/o balance but I didn't want to put it all together to find out. I've reved the car up past 5500RPM a few times already and its smooth as glass. Yes, I believe you can use your same PP & TB. Just use pieces intended for corvette and it will work. If you have a solid hub clutch disc you may want to consider going to a camaro type with a sprung hub. It will aid in dampening any kind of rattling you may induce with the single mass conversion. I used an SLP (lightenend LT4) pressure plate, camaro disc, and GM Corvette TB. I bought the SLP PP w/o thinking it through, it came w/ a camaro TB which won't work. So I orded the stock TB from samtaylor.com for $75 and replaced the camaro unit.

I just reread your post. If you are building another engine then when/if you have it balanced take everything including the FW into to have it balanced together. Should work out beautifully.


[Modified by y5e06, 12:23 PM 2/27/2004]

 

i changed to an single mass, using a camaro FW machined down .080, was running fine...drove about a summer with that setup, without vib.problems

finally when i did my engine upgrade, i had the whole unit fine balanced, was only of about 4 grams..now..0 :D

 

well it looks like I'm on the hunt for a camaro flywheel, any help will be great in finding a deal on one, thanks

 

Post a WTB add in camaroz28.com classifieds forum. I got mine from there for $40 shipped.

md