Original Cobras with 428s what hp?

[olddog]

Many original Cobras were sold with 428 FE engines. Were these the same 428 CJ engines that Ford put in everything else or did Shelby do anything to them to bring them up closer to the 427 FE?

Everything I have read listed the 427 SO at 425 hp, but manufactures were playing with the numbers a bunch back then. So much so that around 72 or 73 the Feds (think this is correct) stepped in with the ASE NET hp standard. So for that matter by todays standards what was the 428 and the 427 engines sold by Shelby actually putting out?

[mrmustang]

335hp..........

[1985 CCX]

I have been told 335hp as well?

[rms427]

I have copies of original spec sheets from Shelby. The 427 competition car was rated at 480 HP, The 427 street engine was rated at 425 HP and and the 428 was rated at 390 HP. However various engines and rear end gears ended up in the cars depending on what was available. The specified rear end ratio on the 428's was 3.31 but my 428 car has 3.54 gears. The specified rear gears in the comp car were 3.77 and the 427 street car specified 3.54.

[rms427]

Here are copies of the Original Shelby Spec Sheets on the 427 Cobras. Unfortunately when I made these copies back in about 1970 the copy machine did not reproduce the red cobras on the 427 spec sheets (just the wheels). I had the color spec sheets at one time but can't find them. Sorry that they are hard to read but I had to reduce the sizes to be able to post them. The percentage numbers are just the amounts I reduced the files.

[rsimoes]

Originally Posted by rms427

Here are copies of the Original Shelby Spec Sheets on the 427 Cobras. Unfortunately when I made these copies back in about 1970 the copy machine did not reproduce the red cobras on the 427 spec sheets (just the wheels). I had the color spec sheets at one time but can't find them. Sorry that they are hard to read but I had to reduce the sizes to be able to post them. The percentage numbers are just the amounts I reduced the files.

Can you email me the original copies (larger)? Thanks!

[Byots]

nm .

[Ron61]

OldDog,

The original 428 engines were from the Thunderbird line per what literature I have on it and was rated at around 355 horse. The 428 CJ engines weren't around back then and he used them in the GT-500KR Mustangs I think.

RMS,

To make your copies where they are easier to read, why not upload them to your gallery and then link them to the post or use some place like Photo Bucket and do the same.

Ron

[rms427]

My original stock 428 engine had low riser 427 heads, 427 AA cam, 10 to 1 compression, aluminum intake manifold and ford autolite 4 bbl. carb. I confirmed all this when I rebuilt the engine.

[Byots]

nm .

[olddog]

Originally Posted by rms427

Here are copies of the Original Shelby Spec Sheets on the 427 Cobras. Unfortunately when I made these copies back in about 1970 the copy machine did not reproduce the red cobras on the 427 spec sheets (just the wheels). I had the color spec sheets at one time but can't find them. Sorry that they are hard to read but I had to reduce the sizes to be able to post them. The percentage numbers are just the amounts I reduced the files.

I'm impressed with the original literature and the car. Thanks

[rms427]

Here is the information I found written down on a slip of paper inside an old parts book. I wrote this down when I was rebuilding the engine in about 1974. I assume the information was off the engine but it was over 30 years ago and I could have just taken it from one of the parts books. In fact, I thought I remembered the intake valves being 2.09" diameter not 2.04. So take it for what it's worth.

1966 428 PI.

Cylinder heads C7AZ-6049-A. Intake Valve 2.04 Ex 1.57. Intake port 1.34x1.93. Ex. port 1.28x1.84.

Intake Manifold C6AZ-9424-H. Ports 1.24x1.94. Carb 2 1.78 by 2.5 ovals.

Camshaft C3AZ-6250-AA Mechanical cam - Lash.025. Duration 306 deg Intake and exhaust with .5 lift.

Pistons Dished with eyebrows.

Rods 762-774 grams with 13/32" bolts

Crankshaft C9ZZ-6303-B Main 2.749 and rods 2.438 with 3.98 stroke.

[Anthony]

Originally Posted by olddog

Original Cobras with 428s what hp?

not enough.

[Woodz428]

Originally Posted by rms427

Here is the information I found written down on a slip of paper inside an old parts book.

Crankshaft C9ZZ-6303-B Main 2.749 and rods 2.438 with 3.98 stroke.

I can't speak to the other items listed...but this one is a 1969 428CJ crank. It wasn't even available at the time Cobras were being made....unless you are referring to the Torino Cobras which had 428CJ engines.

[Byots]

nm .

[KeithBrown]

Here is a red copy of the brouchure - I have no idea where I got it from.

[theturd]

Would like to point out that the 1967 post card that i have also quotes a 428 engine. It just amazes me how many people are still confused about the 428 car.
Vern

[Badsnake427]

Does anyone know how many of the originals came with the 428?

[Ron61]

If you have the 1997 registry you can look it up. If not, then take the easy way and wait until Ron(CW) sees this and he can answer it without having to look through the registry. I am pretty sure the n\first 60 CSX3XXX cars were 427 comp cars with single 4 barrels and then he went into the 428s and finished the 3000 series with 427s with dual 4s.

Ron

[Badsnake427]

Thanks Ron, much appreciated.