"Factory" lightened flywheel??

[opelspyder]

I stumbled across a flywheel that I instantly noticed it was cut smaller than the usual stock 1.9 one. Didn't think about it for a while, but noticed it was a lot easier to handle(not as heavy) Then I began to wonder what it was from...1.5??? I looked in part number books and they only list the one for 1.9 and 1.5. Does anyone know what engine this flywheel had come from. The cut down area is not actually cut down, but it is left in a rough cast finish. Obviously a factory job, but wondering. The holes are all the same-the ball for timing is indexed the same, and the oil drain holes/debris holes are the same. It might be something the racers are interested in that cannot modify their flywheel,but can run only a factory one. Here are pics
Keith

[tomking]

You have an automatic and automatics do not have flywheels. So dont bother with one. Autos use a flexplate that you do not lighten. Whoops! Sorry I responded to the wrong post. Keith you obviously know what you have ( and I dont!)

[hrcollinsjr]

Keith,

I believe that is a stock 1.9 flywheel that has been cut down.

Harold

[RallyBob]

I'd say the same thing, looks like a modified stocker.

[opelbits]

I'd agree that it looks cut. Too nice of a radius for a casting.

Can you weigh it? See how it compares to a stock one. Mine is cut down almost exactly the same way, but I never weighed it.

Since we are on the topic, can anyone make any statements concerning the removal of material at the outer edge only (such as in the picture) versus doing the all over lightening? Is one preferable over the other? Does one have more of an impact on idle quality, yet still allows it to rev a faster? I know it's the whole mass/inertia/rpm thing, but reducing mass solely at the perimeter would seem to have different characteristics than removing the same weight from the backside.

[opelspyder]

Guys I know what a cut down one looks like, and the cut down area is not smooth machined-it is actually cast rough. There are no machine marks on it. It would be near impossible to mimmick the cast rough finish there, and if you did, why go through the trouble. I will sandblast this and take some closeups. This came from a house where I aquired two cars and lots of engine parts. All were early engines and parts-I just thought it might be from a 1.5 car
Keith

[RallyBob]

FWIW, when we used to run 'stock' classes in mini-stocks, I typically went through a lot more trouble hiding the modifications than actually making the modifications!

This included things like using a needle-scaler on machined surfaces, then sandblasting, then leaving the parts outside in the rain and sprinking salt on them. Basically if the tech guys thought it looked stock they let it go....

[opelspyder]

It may be due to it being very rusty, I blasted it, and it is still hard to tell. If it was cut down they cut the inside as well because there are no marking inside either. This has got to be about 25 years old, did come from VA-might be some Rallye Bob work
Keith

[opelbits]

I checked my books (Dated '76), and they show only one flywheel for 1.5 and 1.9 engines for 68-75. Prior to that is the 66-67, which also shows one flywheel, but no engine breakout, so I assume that is the 1.0/1.1.

Also, looking at the pics, the ring gear looks narrower too. I'll bet if you put a straight edge across the backside, you'll find the ring gear is absolutely flush with the edge of the flywheel. No chamfers, no mating groove, just totally smooth. Pretty mean trick to get a ring gear that flush all the way around without machine work.

[hrcollinsjr]

Originally Posted by opelbits ... so I assume that is the 1.0/1.1.

I have a NOS 1.1 flywheel, not even close to a 1.9 flywheel.

Harold

[opelnut10]

Originally Posted by RallyBob FWIW, when we used to run 'stock' classes in mini-stocks, I typically went through a lot more trouble hiding the modifications than actually making the modifications! This included things like using a needle-scaler on machined surfaces, then sandblasting, then leaving the parts outside in the rain and sprinking salt on them. Basically if the tech guys thought it looked stock they let it go....

I like the way you think Bob, should have been a drag racer I am guilty of having knowledge about that masterpiece, it looks like the flywheel that we made for Tommy Tice (Red Kadett Wagon in my pictures) it had about 4 pounds trimmed off and yes, the tech people said "yelp, looks stock to me"

[opelspyder]

This came from an Estate of a well known Opeler in the VA, Fairfax area off I-66. His name was Bill Schmidt who passed away. He was going to leave the cars to either my grandfather Frank, or some Opel club...well thankfully he left them to us. Bill didn't seem to be into racing, but then again when I think about it, he did have several upgrades on the 69 GT I got from him. Head work done, lowering springs, ect. Maybe he came across it back then. He quit fooling with Opels about 1990, and judging where it was, well it had been there quite some time. Whoever did it, did it right, meaning they didn't leave any sharp edges (round nose lathe bit used) And tapered out the inner cut so well it looks factory. So now...who wants to buy a professionally lightened flywheel?????????
Keith

[opelbits]

Speed is just a question of money...how fast do you want to sell it?!

[opelspyder]

Would have sold it yesterday if I knew you wanted it. Well possibly. Email me and we can talk-set you in it right
Keith

[jeff denton]

Originally Posted by RallyBob FWIW, when we used to run 'stock' classes in mini-stocks, I typically went through a lot more trouble hiding the modifications than actually making the modifications! This included things like using a needle-scaler on machined surfaces, then sandblasting, then leaving the parts outside in the rain and sprinking salt on them. Basically if the tech guys thought it looked stock they let it go....

Yeah, guys. You should see a "New England Intake" sometime.

As for lightened flywheels, how, when, what, where, and why, there is a thread that goes into extreme detail.

[mod mini gt 75]

jeff the flyweel I run . Its a1500 flywheel that was cut down in 1975 .When i was running a 1.5 eng. Yes the flywheels are the same. My flywheel was cut down to 17.5 pounds. It looks a little lighter then one you picked up. I now have it on a 2.0 with a1.5 head. Now looking into cutting a new flywheel down to fit the Chevette pressure plate. But with a twist. Cutting the flywheel down at the edge of the pressure plate and then going to run a automatic flex plate behind it. We can't run an aluminum fly wheel. Will send pictures of mod mini gt soon.

Steve

[tomking]

Originally Posted by mod mini gt 75 jeff the flyweel I run . Its a1500 flywheel that was cut down in 1975 .When i was running a 1.5 eng. Yes the flywheels are the same. My flywheel was cut down to 17.5 pounds. It looks a little lighter then one you picked up. I now have it on a 2.0 with a1.5 head. Now looking into cutting a new flywheel down to fit the Chevette pressure plate. But with a twist. Cutting the flywheel down at the edge of the pressure plate and then going to run a automatic flex plate behind it. We can't run an aluminum fly wheel. Will send pictures of mod mini gt soon. Steve

Well seeing the pics would be interesting. Fernely NV eh? I almost built a plant in Fernley and would have moved there to run it. I always wanted to live in the West but it never happened. I cant say though that Fernley looked terribly appealing as a place to live, especially to my wife. Good Opeling out there in the high desert.

[opelbits]

The flywheel in question (Thanks Keith!) weighs in at about 18.5 lbs. The stock one I have is 22.5 lbs. This is according to a cheap bathroom scale. It may be off a little.

Anyone know offhand what the stock weight is specifically? I'd like to believe the scale is actually reading high...if you know what I mean..

[yellaopelgt]

22.5 is what mine weighed in at before I had it lightened. I had mine taken down to 16.5...........
HTH
Joe

[RallyBob]

Since they are cast iron and there are variances, I've measured stock flywheels at anywhere from 22.5 lbs to 23.25 lbs.

[hrcollinsjr]

Originally Posted by yellaopelgt 22.5 is what mine weighed in at before I had it lightened. I had mine taken down to 16.5........... HTH Joe

Street car? And how long did it take you to learn how to drive smoothly with it?

Harold

[yellaopelgt]

Originally Posted by hrcollinsjr Street car? And how long did it take you to learn how to drive smoothly with it? Harold

yea I know...... but havent actually fired this thing up yet.(I AM getting real close here.Just need to figure out my new add one wiring with relays) I'm hoping the added weight of an s-10 clutch will help make it run smoother and be easier to shift.

[RallyBob]

Originally Posted by yellaopelgt yea I know...... but havent actually fired this thing up yet. I'm hoping the added weight of an s-10 clutch will help make it run smoother.

It'll be fine. I ran a 15.5 lb flywheel with 8" Opel clutch on an 11.2:1 compression/big cam engine for years with no issues, daily driver and all.

The S-10 clutch is 9.125" in diameter, and while it weighs minimally more than the Opel clutch, it has more inertia and is very driveable as a result.

I used my first S-10 clutch on a 14 lb lightened flywheel on a stock engine and it drove beautifully. Lighter pedal effort, smooth engagement, no chatter.

Bob

[yellaopelgt]

Originally Posted by RallyBob It'll be fine. I ran a 15.5 lb flywheel with 8" Opel clutch on an 11.2:1 compression/big cam engine for years with no issues, daily driver and all. Bob

This is basically my recipe as well. And we had discussed this on another thread,thats why I went with it. Soon.....real soon,I'll be turning the key over !!!!