New engine questions

[MYSTANG]

Greetings to all,

I have a couple of question about the new engine that I’m swapping into my car. But first, here’s what I’m working with.

I have a 66 mustang coupe with a 200 I6 and a 2.77 3 speed (non-syncro), both are getting tired. I purchased a complete 200 I6 with c4 transmission (side of block reads 5x, D8BE, 6015GC) out of a 78 Fairmount. Engine and transmission has 25,000 miles. I am in the process of taking the oil pan and pickup tube off the old engine and putting them on the new engine. The car, 78 Fairmont, came from California and I am removing all of the emission stuff since it’s not needed. I will be sell all of the emission stuff and c4 transmission once I get the engine transferred into my 66 mustang.

My goal for the car: Daily Driver (66 Mustang Coupe)
A) Headers
B) New cam
C) New crab. (2v or 4v)
D) 8” rear-end (already have a 8” out of a 72 Marv w/2.79:1 gear ratio)
E) T5 transmission (1985-93 Borg Warner)

After pulling the engine and transmission from my car (66 Mustang), I found that I have the following:
Bell Housing # C6OA-6394-C
9” Clutch

Questions: Fly Wheel:
Since, the new engine had an automatic (c4) behind it and I will be using a manual (t5):
(1) Which fly wheel should I use? Take the fly wheel off the old engine (manual 3 speed) and put it on the new engine or use the fly wheel (automatic c4) which is already on the new engine. The reason I ask, the fly wheel on the new engine (with auto. C4) seem smaller than the fly wheel (manual 3 speed) on the old engine.

(2) If the old fly wheels needs to be swap to the new engine, will the old fly wheel have to be (re) balance, before being put on the new engine.

Question: T5 Transmission:
After, looking at my goals for the car:
(1) Which T5 should I use? ( 4 cycle version or v8 version)

Any and all suggestion will be greatly appreciated.
Thanks in advance.

Mystang

 

[rocklord]

Greetings to all,

I have a couple of question about the new engine that I’m swapping into my car. But first, here’s what I’m working with.

I have a 66 mustang coupe with a 200 I6 and a 2.77 3 speed (non-syncro), both are getting tired. I purchased a complete 200 I6 with c4 transmission (side of block reads 5x, D8BE, 6015GC) out of a 78 Fairmount. Engine and transmission has 25,000 miles. I am in the process of taking the oil pan and pickup tube off the old engine and putting them on the new engine. The car, 78 Fairmont, came from California and I am removing all of the emission stuff since it’s not needed. I will be sell all of the emission stuff and c4 transmission once I get the engine transferred into my 66 mustang.

My goal for the car: Daily Driver (66 Mustang Coupe)
A) Headers
B) New cam
C) New crab. (2v or 4v)
D) 8” rear-end (already have a 8” out of a 72 Marv w/2.79:1 gear ratio)
E) T5 transmission (1985-93 Borg Warner)

After pulling the engine and transmission from my car (66 Mustang), I found that I have the following:
Bell Housing # C6OA-6394-C
9” Clutch

Questions: Fly Wheel:
Since, the new engine had an automatic (c4) behind it and I will be using a manual (t5):
(1) Which fly wheel should I use? Take the fly wheel off the old engine (manual 3 speed) and put it on the new engine or use the fly wheel (automatic c4) which is already on the new engine. The reason I ask, the fly wheel on the new engine (with auto. C4) seem smaller than the fly wheel (manual 3 speed) on the old engine.

(2) If the old fly wheels needs to be swap to the new engine, will the old fly wheel have to be (re) balance, before being put on the new engine.

Question: T5 Transmission:
After, looking at my goals for the car:
(1) Which T5 should I use? ( 4 cycle version or v8 version)

Any and all suggestion will be greatly appreciated.
Thanks in advance.

Mystang

(1) You have to use the flywheel from your Mustang. The C4 does not have a flywheel but a flexplate that the torque converter bolts to.
(2) The old flywheel doesn't have to be rebalanced before installing it. It may have to be resurfaced if it has hot spots.

T5 - If you're going to use the 2.79 gearing in the Maverick 8-inch, go with the 4Cyl T5; You'll get better offline starts without excessive clutch slipage. If you purchase a 4 Cyl T5, make sure you get the correct input shaft bearing; the one for the V8 T5 is too large. Also, when you purchase the adapter for the T5, you will have to use the one specifically made for the 66 bellhousing. Check it out below:

http://www.safepay.net/cgi-bin/shop/car ... ndriveline

Hope this helps.

 

[Eric Rose]

Where in GA are you located?

 

[MYSTANG]

Rocklord, Thanks again for the reply...
I also found this adapter plate from California Mustang. See link
http://www.cal-mustang.com/1966-MUSTANG-6-CYL-T5-SPACER-ADAPTER-PLATE-P8111C330.aspx
It states that it should fix my bellhousing which have the casting #C6OA-6394-C

Question: If I change the rear-end gearing from 2.79 t0 3.25 0r maybe 3.50 should I then use a v8 t5.

I'm located in Powder Springs; West Cobb.

 

[FalconSedanDelivery]

Depending on the tire size ( overall diameter ) , even 2.79 is fine with reg v-8 T-5 . your overall gearing is still 9.35 ( 3.35x2.79), its the 2.95 first geared T-5 ( Cobra V-8's and upgrades only )trans , that would be slightly geared high , I would be more concerned about the overdrive ratio with the V-8 T-5 as its a .68 ( in most cases ) .68 x 2.79 = 1.89 , Way too tall for anything but a big cubed Bonniville salt flats car , However , getting the right rear gear , say 3.25-3.80 ( depends on usage and Tire diameter ) still better than buying 2 transmissions . so I say Use a V-8 T-5, the switch to a little more gear later

 

[rocklord]

I've got a 4Cyl T5 WC with plans to use an 8-inch Maverick rear end with 3.27 gears. This will give me an overall gearing in OD of 2.58 (3.27 x 0.79).
This overall gearing would be equivalent to running 3.73 gears with the typical V8 T5 WC (3.73 x 0.69 = 2.57).

3.25 gearing would be find with a 4Cyl T5. If you go with anything numerically higher (3.50, 3.73, etc.), then you should go with the V8 T5

The 4Cyl T5 WC is rated for 240 ft lb torque, the V8 T5 WC around 300. If you look at the dyno runs on the CI site, all of the NA 200s tested were below
the torque rating for the 4Cyl. If you were planning on turbocharging your 200, or installing a 250, go with the V8 T5.

An upside to the 4Cyl T5 is that they can be less expensive to purchase.
A downside is that the steel input shaft bearing housing (what the TO bearing rides on) is difficult to find, and expensive if you do; so make sure the the
aluminum housing is in decent shape, or the TO bearing could bind on it.

Hope this helps.