5.0 HO Flywheel

RXTbone

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Mar 30, 2005
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This has been answered somewhat in previous threads - but not specifically enough that I feel comfortable moving forward...

I have a '66 fastback - and I am installing a 5.0 HO. I have a 289 donor that I'm using the oil pan and pickup from. I plan on hooking the 5.0 to the 4sp Toploader that is original to the car.

Do I use the flywheel from the 5.0, or the flywheel from the 289? Any clutch suggestions within a reasonable price?

Any info would be appreciated!

Thanks!
 
Since you engine is newer you will want to use a 50oz flywheel. If you were using an older engine you would use a 28oz. The only thing I am unaware of is the compatibility of a H.O. 50oz flywheel and the toploader's pressure plate. I am sure someone can answer that here.
 
Yeah - I think that would be my next question. Makes sense the flywheel would remain - I guess what I need to know now is what type of pressure plate I need. It certainly doesn't appear that the old (289) pressure plate works...

Thanks for the help!
 
From what Ive read, you would need to use the 5.0's flywheel (50 oz imbalance) and a pressure plate matched to it. (the stock 289 design does not use the same type of pressure plate. Diaphram vs long style?) The combo that I have going into a 5.0 is the following (mind the assembly is balanced to 28 oz, instead of 50)
1) 157 tooth, 28 oz imbalanced flywheel, drilled to work with late style pressure plate
2) 93 mustang Centerforce 2 pressure plate. (The pressure plate needs the dowel pins, and the old 65 set up didnt have the provisions for it). Also, the clutch/pressure plate need to match the spline of the toploader.
Tranny is a 10 spline toploader that used to work behind the 289. I think it should work?
 
Sounds like you're trying to do the same thing I'm doing, just going about it differently. So I understand - you're basically remachining the 289 flywheel to accept a newer 302 flywheel's pressure plate (164 tooth, 50 oz.)?

So, if the Centerforce 2 pressure plate works for you - it should work for me?

Thanks for the help - I figured with a million 302's around, people would be throwing part numbers around - but I suppose maybe the toploader is the issue with most people using the T5's...

Thanks again!
 
You must use the flywheel required by the engine. Since you have a 5.0HO, you need a 50oz flywheel. Be warned that if you use a stock flywheel for a 5.0, the pressure plate bolts are metric.

I have a roller 5.0 I built myself and have a 50oz aluminum flywheel with a Toploader and a Ram 3-finger clutch. The clutch was a good price from Summit at about $165. I ordered one for an early Mustang, NOT a 5.0.

My flywheel is a Fidanza universal 157 tooth model that can be used on zero, 28oz, and 50oz balance engines with up to a 10.5" clutch. It also has SAE 5/16-18(early) and metric pressure plate bolt holes, plus it came with seperate dowel pins also for use on a latemodel 5.0 with the diaphragm clutch.

On a side note, if you are using the stock z-bar clutch linkage, you'll need a special z-bar pivot bracket that mounts onto the bellhounsing bolts because the roller blocks lost the mounting point. If you use a scattershield and not the stock bellhousing,it will also need spacers like this:

View attachment 419166
 
Flywheel: you need the flywheel to match the engine's imbalance, in this case the 5.0L HO's 50oz imbalance.
--Use the 289 flywheel, but rebalanced to 50oz and the older style three finger pressure plate or machined for dowels to accept late-model pressure plates
--or use the stock HO or upgraded replacement 5.0L flywheel. The second option (and the remachined, rebalanced early flywheel) allows you to use any 10.5" clutch made for the HO--Centerforce, Ford Motorsports, stock 1982-1995 HO replacement clutch, RAM, Spec, etc., and the diaphragm style pressure plate.

The throwout bearing will follow the style of clutch arm--vintage bellcrank use vintage TO bearing, cable/hydraulic later-model style use late model throwout bearing.

I'd also suggest changing to a roller pilot bearing instead of the vintage bronze one for slightly less drag.

Bellhousings--use scattershield (bellcrank style linkage), 1982-1993 Mustang HO bellhousing with cable clutch or vintage bellhousing with vintage bellcrank style clutch linkage.

Small block toploaders and V8 T-5s both have 10 splines and are the same diameter so both fit either style flywheel. Just make sure on the imbalance.
Make sense?
Daniel
 
BorninaFord: You put that very well. thats what I was trying to explain in my previous post...it just didnt come out that clean.

RXTBone: Im not changine that tooth count on the flywheel. My 289 flywheel originally was a 28 oz imbalance, 157 tooth count flywheel. Like posted, to make it work with a 50 oz imblance 5.0 and a late style diaphram style pressure plate set up, you would need to have it machined to 50 oz imbalance, and have the dowel pins drilled to match it to the pressure plate.
I chose to avoid all of that, and go with a new 157 tooth flywheel and im my case balanced to 28 oz's, that has provisions for both the old style pressure plate, as well as newer style pressure plates. The size of the flywheel also matters. I went with a 10.5 inch flywheel, as that lets me go with the matching 10.5 inch clutch and pressure plate combo.

Heres my parts list and parts numbers from summit:

RAM-1527
Flywheel, 157-Tooth, 10.50 in. Diameter, Steel, 24.0 lb., External Balance, Ford, 221-302/351W

CTF-DF021048
Clutch Kit, Organic, 1 1/16 in. Diameter Shaft, 10-Spline, 10.4 in. Diameter Disc, Ford/Mercury, Kit

This sould work together I think? Quick question: Whats the deal with pilot bushings? Which pilot bushing is needed? One for a 65/66 or one for a 5.0?
 
I'd use the later model roller pilot bearing. It's the same size as the stock 66 bronze bushing, goes in the same way, but is freer in movement so frees up a tiny bit of power. It is a bit more expensive, but you can get it from NAPA or autozone for under $20, IIRC. Ask for a 1990 Mustang GT pilot bearing or something like that. :D
Daniel
 
I'd use the later model roller pilot bearing. It's the same size as the stock 66 bronze bushing, goes in the same way, but is freer in movement so frees up a tiny bit of power. It is a bit more expensive, but you can get it from NAPA or autozone for under $20, IIRC. Ask for a 1990 Mustang GT pilot bearing or something like that. :D

+1

The bronze pilot bushings and roller pilot bearings are dimensionally the same. I have a roller pilot for an '89 5.0 Mustang in my '68. '87-93 5.0 Mustang roller pilots are all the same p/n. Mine cost somewhere between $12 and 15.