[Brett]

Buddy of mine who is installing my 350 and new 4 speed just called and indicated the stock 6 cylinder flywheel couldn't allow the pressure plate to be bolted up. I was thinking I'd researched all the 6 banger to 8 conversion pitfalls, but guess I missed this part. Car is 65, using stock 6 cylinder bellhousing and new clutch package is Zoom 10.5", 26 spline to mate to new Richmond T-10. Anyone ran into similar problem? If I have to locate a different flywheel, do you think it'll fit inside the stock smallish 65 bellhousing (it's the "509" or "309" number, what it is, that is same for both 65 V-8 and 6 cylinder). Appreciate yoru comments/thoughts.
Brett.

 

[Mike Goble]

Just get a 153 tooth flywheel. There are a lot of them on the market.

 

[Brett]

I thought my stock '65 6 banger flywheel was 153? That's kinda why I'm lost. I thought there was only 2 flywheels, 153 and 168 and I thought a stock 65 flywheel was 153, because I figured Chevy went to 168 in about 1968 or so? But, I'm far from knowledgeable about flywheels.

 

[Mike Goble]

Which came first, the flywheel or the clutch? If the clutch won't attach to the flywheel, did you buy the right clutch?

 

[Brett]

Here is where I believe I'm stuck. I think the stock 65 bellhousing will only permit a 153 tooth flywheel and a 10.5 clutch. The new Richmond I have is 26 spline input shaft, so that is the Zoom clutch package I have (new also, 10.5"/26 spline).
However, I'm surmising the pressure plate mounting bolts must be in a different pattern between 153 and 168 tooth flywheel, and because my clutch package is 26 spline, it is designed to be mated to a (newer) 168 tooth flywheel that won't fit in my stock 1965 bellhousing.
So, I'm thinking I'm going to have to buy a Lakewood bellhousing (seems I've read they make a Chevy II specific application where the clutch fork comes out at 7 oclock) and probably a 168 tooth flywheel to make everything work. Again, I really do appreciate reading time/advice/thoughts/opinions, Brett.

 

[Mike Goble]

We run a Tex Racing ST-10 with a 26 spline input using a stock bellhousing, a Centerforce DF clutch and a Fidanza flywheel. It seems to me that it would be more cost effective to get a flywheel that fits the clutch than to get the complete bellhousing, clutch and flywheel. The use of a larger flywheel will also bite into your selection of headers and starters, some fit, some won't.

 

[Paul Wright]

Here is where I believe I'm stuck. I think the stock 65 bellhousing will only permit a 153 tooth flywheel and a 10.5 clutch. The new Richmond I have is 26 spline input shaft, so that is the Zoom clutch package I have (new also, 10.5"/26 spline).
However, I'm surmising the pressure plate mounting bolts must be in a different pattern between 153 and 168 tooth flywheel, and because my clutch package is 26 spline, it is designed to be mated to a (newer) 168 tooth flywheel that won't fit in my stock 1965 bellhousing.
So, I'm thinking I'm going to have to buy a Lakewood bellhousing (seems I've read they make a Chevy II specific application where the clutch fork comes out at 7 oclock) and probably a 168 tooth flywheel to make everything work. Again, I really do appreciate reading time/advice/thoughts/opinions, Brett.

I think you are overthinking the problem.

The clutch disc spline count doesn't change the clutch cover (aka pressure plate) bolt pattern. A 10.5" clutch cover should fit a 153 tooth flywheel. The only thing I'm not sure of is if the 6 cylinder bellhousing is the same as the V-8. If they are then you shouldn't have a problem.
If your buddy is swapping in a 350 he may be using a later and therefore larger clutch and flywheel.

 

[Brett]

Paul, you might be right, he might be pulling from the wrong stash of parts at the location and I'm trying to think through this based on a cellphone call that was breaking up some anyhow, so I haven't physically seen the problem yet and won't get to until tomorrow morning. I have the stock 65 flywheel (freshly resurfaced) and brand new Zoom assy (clutch/pressure plate/throwout bearing) and stock 65 bellhousing (which I understood to be same regardless of 6 or 8 in 1965-1967), so I'm not comprehending what the problem is either. I do have a spare flywheel to take down there tomorrow to see any difference. I guess I shouldn't be asking until I go down there and physically see the problem, it could be as simple as he's grabbed from wrong stash of parts. Thx, Brett

 

[the FLYER]

Hey Brett... send me some'a that there STASH, would ya ???

 

[Brett]

figured out problem

I placed the original 6 cylinder pressure plate face to face with an early 283 pressure plate I had laying around and saw the problem, pressure plate bolt hole location. 6 cylinder pressure plate is smaller diameter and therefore bolt holes in smaller pattern on the flywheel. So, no, one cannot reuse a 6 cylinder flywheel for a V-8 swap.
Had my car been an original 283 car, I'd have been good to go in all respects (reusing the flywheel). Brett.

 

[Scooter]

What if you use a six cylinder clutch with the six cylinder flywheel but bolt it to a v8? Aren't the crankshaft holes the same?

-Aaron

 

[Bruce]

The mounting flange on the crankshafts are the same for the 194-250 inlines as they are on the two piece main small blocks. I do not remember when the 26 splines came out as oem from GM, but pressure plate mounting difference may be due to the 26 spline having different bolt patterns than the 10 spline.
If the clutch assembly that came off the 6 is actually a 10.5", will the 26 spline disk work with the original pressure plate?


While many may not agree, as the Lakewood is far safer, I would stay with the 153 tooth flywheel and stock bellhousing. Changing out a clutch with a Lakewood is a major pita compared to the stocker.