Welcome to the Corvette Forums at the Corvette Action Center!

L-98 Engine Question

Joined
Feb 25, 2003
Messages
887
Location
Clarksville, Tennessee
Corvette
1979 Bright Red L-82
What is this large round metal with the four bolts on it for? ;shrug
7190L-98_Vette_Motor.jpg
 
H

hawaii-5-lo

Guest
hey Daryl,thats the 'frisbee',i took mine off when i had my 89,i think it is suppose to absorb any harmonics from the motor so none off the aluminum brakets crack from vibration,it also acks as a balancer,i think,because mine had holes drilled in one area,i dont know if its related,but shortly after i took mine off, the alternator braket cracked,that little ear piece at the small end.my quarter mile times did not change after removing it,but it must rob a little horsepower,later,Todd
 
Joined
Oct 30, 2001
Messages
2,273
Location
Glen Burnie, MD, USA
Corvette
1986 Bright Red Coupe
If I'm looking at the picture right, you've outlined the harmonic balancer - as others have said. It also has the timing marks on it, IIRC, and the whole pulley is the crank pulley - turned directly by the engine and what is driving the accessories.
[RICHR}
 
Joined
Feb 25, 2003
Messages
887
Location
Clarksville, Tennessee
Corvette
1979 Bright Red L-82
If you take the four bolts off only the big round thing comes off not the pulley......but it must be like hawaii 5 said, keeps some of the brackets from cracking.....thanks again.....just wandering what purpose it had......:D
 
H

hawaii-5-lo

Guest
rrubel,its not on the crank, its bolted to the pulley thats bolted to the water pump,i dont think the 85s had this because i believe all your brackets are steel not aluminum.of coarse i could be wrong about yours being steel,put a magnet up to them, if it sticks its steel, if not its aluminum. on the 89 i had they were aluminum,so i polished them,now im polishing all the aluminum on my 99,it never ends,later,Todd.
 
D

Da Hawaiian Punch

Guest
hawaii-5-lo said:
hey Daryl,thats the 'frisbee',i took mine off when i had my 89,i think it is suppose to absorb any harmonics from the motor so none off the aluminum brakets crack from vibration,it also acks as a balancer,i think,because mine had holes drilled in one area,i dont know if its related,but shortly after i took mine off, the alternator braket cracked,that little ear piece at the small end.my quarter mile times did not change after removing it,but it must rob a little horsepower,later,Todd
Howzit buddy of mine!!
You failed to let Darryl know that the reason that your alt braket cracked was not because of removing the "frisbee" but because of the instalation of the alt that was'nt working down stairs from where we lived at the time, remember? ;)
I took mine off and have not have any problems after doing so, as far as 1/4 mile times, dont know, never raced with it on there before I raced without it.;)
 

vader86

Well-known member
Joined
Sep 5, 2001
Messages
807
Location
Baton Rouge/LSU
Corvette
1986 White Coupe w all options.
its a 10lb weight that GM added to the front of the water pump, remove it

The frisbee didnt start until 88
 
H

hawaii-5-lo

Guest
it must have been 88 when they changed to aluminum brakets im guessing,i ran without it for a while and Da Punch does also,but you gotta think GM put it there for a reason.it does add un-sprung weight,if you do remove it,just check your brakets every time you clean your engine.thats once a week for me.;LOL later Todd.
 

EDDYVETTER

Member
Joined
Mar 4, 2003
Messages
17
Location
nor-cal
Corvette
73 Black coupe<>85 black coupe <>2002 black Z06
They started in 88. It was supposed to help with the new air conditioner compressor that was being used. They stoped using it in 92. The general feeling on this is to remove it. My buddies is off. I heard that it won't affect the compressor at all. It helps by taking the weight off the water pump, less mass to turn on the pully. Thats why they say it increases HP. He Felt no difference when it came off, but it did run smoother. Hope that helps .
 

Ken

Gone but not forgotten
Joined
Jan 30, 2001
Messages
8,236
Location
Hermosa Beach, CA
Corvette
1987 Z51 Silver Coupe
Funny, but I finally got to see one of those things today. I've heard of the "frisbee" before, but I just had to see what you guys have been talking about. Heavy piece too, ain't it? :gap

_ken :w
 
Joined
Oct 30, 2001
Messages
2,273
Location
Glen Burnie, MD, USA
Corvette
1986 Bright Red Coupe
hawaii-5-lo said:
rrubel,its not on the crank, its bolted to the pulley thats bolted to the water pump,i dont think

Ok, then I'm definitely looking at the picture wrong...

At least some of the brackets on the 86 are aluminum - light weight and easily scratched, though I haven't tried the magnet test.

If it's on the water pump, is it perhaps to even out any vibrations there and keep the coolant from cavitating?
[RICHR]
 

Ken

Gone but not forgotten
Joined
Jan 30, 2001
Messages
8,236
Location
Hermosa Beach, CA
Corvette
1987 Z51 Silver Coupe
Don't anyone get offended, but...

That is the idea -- to act as an assist in removing vibration and thus preventing the cracks to the bracketry. It's already been stated several times in this thread. :L

_ken :w
 
Joined
Oct 30, 2001
Messages
2,273
Location
Glen Burnie, MD, USA
Corvette
1986 Bright Red Coupe
Ok, Ok... there were so many theories floating around I couldn't tell WHAT was the truth (the truth is out there... :) ).

Danged new-fangled engines...

[RICHR]
 

Corvette Forums

Not a member of the Corvette Action Center?  Join now!  It's free!

Help support the Corvette Action Center!

Supporting Vendors

Dealers:

MacMulkin Chevrolet - The Second Largest Corvette Dealer in the Country!

Parts/Accessories:

Vetteskins

Advertise with the Corvette Action Center!

Double Your Chances!

Partners

Top Bottom