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'85 302 Roller Block in '66 Mustang

  • Thread starter Thread starter Red66GT
  • Start date Start date Jul 9, 2004
R

Red66GT

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Jul 14, 2003
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Simi Valley, CA
Jul 9, 2004
#1
  • Jul 9, 2004
  • #1
I'm getting ready to do my swap ('85 HO Roller in 66 stang) but am unsure of some things that I'm hoping some of you can shed some light on.

I'm already aware I'll have to get a 50oz flywheel and harmonic balancer.
What about the distriubutor? Do I have to replace the iron gear w/ a steel gear for use w/ a roller cam?

Also, I have a 4spd manual tranny and am planning on buying a new clutch, do I buy a 66 Mustang clutch or an 85 (to match the block), or does it even matter?

Anything else I should be aware of that may be problematic when doing the swap? or is it pretty much a straightforward and simple?

Performance: The 85 HO Roller block is rated at 210hp and 270torque, my '66 A code was rated at 225hp and 300 or so torque back in it's day. Now I'm aware that they tested the engines in the 60's a different way than they did in the 80's, so how much more powerful do you think the 85 Roller is even though the numbers aren't llisted as being as high?

Any input on any of these Q's is greatly appreciated.
 

66bluefb

Member
Feb 6, 2002
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okla.city,okla
Jul 9, 2004
#2
  • Jul 9, 2004
  • #2
You can buy a 85 gt mustang dist. with a steel gear for 50.00 and go ahead and buy dura spark box for 15.00 and change to a duraspark ignition.Buy a 85 clutch and pressure plate and use the 66 throw out bearing
 
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Red66GT

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Jul 9, 2004
#3
  • Jul 9, 2004
  • #3
66bluefb said:
Buy a 85 clutch and pressure plate and use the 66 throw out bearing
Click to expand...

Do I have to use the 66 throw out bearing? or can I use the new one that'll come w/ the 85 clutch kit?
 

Loup-garou

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Aug 11, 2001
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New Orleans, LA
Jul 10, 2004
#4
  • Jul 10, 2004
  • #4
I think the throwout bearing is interchangeable - check with Centerforce or some clutch manufacturer; they may have an online catalog that'll allow you to compare T/O bearing part numbers for both applications.

Also, I see that you've got a 4-speed. Do you have the required clutch bracket to bolt to that '85 block? The roller-cam blocks don't have the cast-in boss with the threaded hole for the Z-bar pivot point.
 

latamud

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Oct 22, 2002
791
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19
Tampa, FL
Jul 10, 2004
#5
  • Jul 10, 2004
  • #5
Loup is correct. Check your block to see if the hole is in the block. most likely it is not there. I did find one on an 84 block once but it was from a towncar. The bracket is about $70 at most mustang retailers.
 
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D.Hearne

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south louisiana
Jul 10, 2004
#6
  • Jul 10, 2004
  • #6
he may run into clutch adjustment problems with the 85 pressure plate, I don't know how it stacks up to the older Long style pressure plates as far as the distance the fingers on it are spaced away from the flywheel. Only way is to try it. The 85 used the same spline count disc as the older ones, so that will not be an issue. If he doesn't want to go the Duraspark route, he can just swap the cam gear on the points distributor to a steel one, just make sure the 85 motor has a roller cam before doing so.The 85 motor is rated differently, so it will have much more power than the older ones.
 

Loup-garou

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New Orleans, LA
Jul 10, 2004
#7
  • Jul 10, 2004
  • #7
Red66GT said:
(snip)
Also, I have a 4spd manual tranny and am planning on buying a new clutch, do I buy a 66 Mustang clutch or an 85 (to match the block), or does it even matter?
(snip)
Click to expand...

Okay, I dug up my notes from when I replaced the clutch in my '65. I used a Centerforce clutch kit, and the only part that was the same in both '65 and '85 applications was the 10" clutch disc. Both the throwout bearing and the pressure plate were different.

Since you're going to purchase a new flywheel anyway, you might consider going with a larger diameter - the '86 and later 5.0 ran a 10.5" clutch, IIRC. Even if you don't race the car, go ahead and build it as stout as you can - the price difference is not significant. In fact, the larger size is much more common and possibly less expensive (certainly more parts to choose from).

If you're keeping the old-style clutch linkage, buy the throwout bearing for the '66 application. Then, buy a pressure plate to fit the flywheel that you choose ('86 or later model). The clutch disk should simply be matched to the pressure plate size. That's the combo I used, and I've had no problems adjusting the linkage with the diaphragm-style clutch.
 
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Red66GT

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#8
  • Jul 10, 2004
  • #8
Thanks for all the info so far guys.

Anyone know where I can buy a steel gear for my 66 distributor?
 
R

Red66GT

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#9
  • Jul 10, 2004
  • #9
Clutch

One more thing real quick on the clutch,
To make things simple, If I buy a Clutch Linkage Kit for 86-93 Mustangs, and a Heavy duty Clutch Kit for 86-93 Mustangs will that be enough? or do I still
have to buy the "required clutch bracket to bolt to that '85 block"?
 
D

D.Hearne

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south louisiana
Jul 10, 2004
#10
  • Jul 10, 2004
  • #10
You will need the Z bar bracket to use the 85 block with a 66 clutch linkage. Also you cannot change flywheel size without swapping to a larger bellhousing too. The flywheel you choose must be the same tooth count and daimeter as the old one to keep using the original bell housing. A linkage kit for fox body Stangs will not work in a 66 without extensive fabrication work to fit it to a 66 Stang
 

SnakeStang65

Founding Member
Jan 11, 2002
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Jasper, Indiana
Jul 10, 2004
#11
  • Jul 10, 2004
  • #11
You will need the steel distributor gear. Make sure that it is the steel one. The steel gear is smooth where the cast iron one is rough.

You can buy the distributor at your local parts store. They typically will stock the cast gear, and have to special order the steel one. Shop arround and you may get lucky and find that one of the stores has one. Make sure that you get the one with the steel gear if you are using the roller cam. Otherwise, the car will start and run, but after about 100 miles, the gear will be completely eaten up by the cam.

John
 

66bluefb

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Feb 6, 2002
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okla.city,okla
Jul 10, 2004
#12
  • Jul 10, 2004
  • #12
When I put my 86-302 in my 66 I bought a 85 gt duraspark dist. from Autozone.But make sure it is steel as mine was but I have heard of people buying the same dist. without a steel gear.You are doing the same swap as I did 2 years ago.I too had a 4 speed toploader but changed to a c-4 last winter so my wife could drive the car.I still wish I had the 4 speed tho
 

Loup-garou

Founding Member
Aug 11, 2001
337
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16
New Orleans, LA
Jul 10, 2004
#13
  • Jul 10, 2004
  • #13
Red66GT said:
One more thing real quick on the clutch,
To make things simple, If I buy a Clutch Linkage Kit for 86-93 Mustangs, and a Heavy duty Clutch Kit for 86-93 Mustangs will that be enough? or do I still
have to buy the "required clutch bracket to bolt to that '85 block"?
Click to expand...


The Fox-chassis cars use a cable-actuated linkage that is much different that the Z-bar or bellcrank system used on the '66. If your original parts are all there and in good shape, all you should need is the flywheel, pressure plate, clutch disk and throwout bearing. Oh, and the pilot bushing or bearing, too.
 

ashford

Member
Dec 19, 2003
485
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16
fargo ND
Jul 11, 2004
#14
  • Jul 11, 2004
  • #14
for the pivot point for the z-bar you can also goto a junkyard and find an early 80's f150 with a v8 and manual they have that bracket for the pivot also
 
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