Need help with 428 cobra jet...

[utvolman99]

All, my father recently passed away. He ran a car repair shop from a 5 bay garage behind his and my mother's house. One of this things I found back there was a 428 Cobra Jet. My father's notes said that it was pulled out of a truck and thought to be a 390. When my father ran the numbers it is indeed a 428 cobra jet (I will double check this). It has a spun bearing but doesn't really look that bad.

 

Anyway, I was thinking of buying this from my mother. I am not sure what it is worth and am not really sure what I would put it in. Here are my questions...

 

1. What is this engine worth?

2. Is this engine special enough to buld the engine then buy a car for it later.

3. I had always planned on buying an older Mustang 65 - 69 fastback and building it for a driver. My plan was to stroke a FI 5.0 roller motor and run a five speed. The Cobra Jet would eliminate the 65 and 66 mustangs and would be a lot heavier. I am not sure what the performance tradeoffs would be?

 

Thanks for your help...

[Mike kZ]

First off, sorry to hear about your father!

The 428 CJ came in 68, to 70 model fords. Here is a web page I found: http://www.fordfairlane.com/428cj.html

[Phantom]

I test drove a 1969 Mustang with the 428 Cobrajet in it in early 1970. Other than it being a bit of a tight fit for me at 6'-4" the most significant memory I have of the car was it walking sideways in 3rd gear when I punched it at 50 mph merging onto the highway. Scared the crap out of my girlfriend. I ended up buying a slightly tamer 340 'Cuda. I'd loe to have either of those cars now.

Ify ou're thinking of putting it in a daily driver don't forget it was not a fuel miser - even by 1970 standards.

[dr_hunt]

The 438CJ motor as it sits is worth at least 3K, maybe more. It is a really good ford motor, actually, one of the best IMO, the 427 side oiler is another. If I were you I'd hang on to that, it's better than money in the bank.

[Gollum]

If it's indeed a CJ then it's worth a pretty penny. The CJ heads where the best production heads of the era except maybe the boss 429 heads.

 

Is the motor special? I wouldn't say so. Ford still produces the CJ series for crate motors so it's not like they're rare. Modern performance parts are much better as well. But the stock motor with forged internals could probly handle some insane powers easily enough. More than enough to be a handful in any car.

 

In theory you could fit the motot in the smaller 65-66 body mustangs, but it just won't be fabrication/modification free. The main reason ford made the mustang bigger in 67 was so they didn't have to vastly modify every mustang to fit the big blocks.

 

Compared to the 5.0 rollers the 428 NA will blow away the potential of the stock 5.0 internals. 500 wheel HP should be easily atainable on a stock 428 block/heads and internals. You gotta consider the starting point for these motors is double the 5.0.

 

I'd say the weight trade off depends on how much work you want to do to the mustang. If you're going to be retro-modding it to have modern suspension I'd say the weight isn't that big of a deal, unless it was gonna be a weekly autox'er or something of the likes.

[utvolman99]

I talked with my brother again and it is indeed a 429 Cobra Jet. I am not sure if this makes a huge difference? What 4 speed transmission would bolt up to this?