Which flywheel do I need?

[Clutch_Grabwell]

My 87 Chevy 350 engine is externally balanced..

It seems that there are two schools of thought about how to categorize the one-piece RMS motors:
There was a small counterweight on the old two-piece crank output flanges. This was in the way when they changed over to the one-piece seal and the weight was relocated to the flywheel/flexplate. The bolt circle also changed to prevent attaching the wrong flywheel.
I'm standing by my definition because your '87 uses a neutral balance harmonic balancer (unlike a 400) and you're obliged to use a one-piece RMS specific flywheel that compensates for the design change.

None of this affects the OP, he appears certain that his motor has a two-piece RMS and all he needs is a third-gen Camaro flywheel for a two-piece RMS.

 

[Chillin014]

Well I checked quite a few websites and they all said the decoding of my casting # was a 2 pc rear main seal. The motor is in the car. Do I really need to find a flywheel from that specific of a year Camaro? "83-86". If the flywheel is 153 tooth, and with the counterweight, would it matter what vehicle it came from and etc?

I appreciate the help, I'm just trying to find a deal on ebay or otherwise and want to make sure I'm getting the right thing. If I have to break down, I'll buy one new after searching.

for example, is there any reason this one wouldn't fit?
http://cgi.ebay.com/ebaymotors/SBC-...r_Truck_Parts_Accessories?hash=item2ea956b5c5

 

[pontiacgp]

I read that add and it says that flywheel has the bold pattern for an 11 1/2" clutch and pressure plate. I don't think I have ever heard of a GM product having an 11 1/2" clutch. What size clutch do you want to use?. I have a 10.5" clutch in mine.

 

[anakputa]

Trucks and Vettes run the large clutch disc.. just go to shucks/oreilly's and buy a new or reman flywheel. I know they have all of them there. Just tell them an earlier model car (Mid 80's camaro or something) and get the flywheel with 153 teeth for the 2 Piece rear main seal, dont forget the flywheel bolt that go on the end of the crank unless you already have them..

 

[pontiacgp]

big blocks do run a larger clutch but it's a 12" not an 11 1/2"

 

[Clutch_Grabwell]

I read that add and it says that flywheel has the bold pattern for an 11 1/2" clutch and pressure plate. I don't think I have ever heard of a GM product having an 11 1/2" clutch.

The seller may have measured the pressure plate bolt circle.
I haven't been able to figure out if the 3rd-gen Camaros use the same flywheels as the old-school four-speeds. A check of the Hollander exchange manual should clear this up.

 

[Chillin014]

that may have been a bad example to use, perhaps I should find another. I don't have a clutch preference although if one is more common than the other I will probably just go that route. I believe I have a 10.5 inch clutch provided by the previous owner of the transmission, not sure if I want to use it or not.

Now that I know that I need a 153 tooth, 2 pc rear seal flywheel, I am trying to understand why I couldnt just use any SBC flywheel that meets those two specifications. For example, if on craigslist the only information in the ad reads "153 tooth, 2 pc rear seal", what are the chances that its going NOT going to work for me?

I am not going to pay 120+ for a brand new flywheel unless I have to...I'm on a budget.

 

[pontiacgp]

take a look at the flange where the flywheel bolts to the crank....if it has a counter balance weight attached to the flange then you need a neutral balanced flywheel...if there is no weight on the flange then you need a weighted flywheel.

 

[Chillin014]

Right, I'll only be able to check that out when I get it all torn apart. I keep reading that all sbc except the 400 are internally balanced though.

the search continues.

 

[pontiacgp]

the 400 is the only external balance as been posted....you need to read over the other posts cause all the information is there.