I am looking at purchasing a 429 that was recently rebuilt and a C6 tranny. The guy who is selling it says its a 429 Thunderjet, i have never heard of this engine, I have heard of the 429 Cobra Jet. Is there a difference or is he mistaken? Thanks

 

Okay I researched into it a little more, this is a 429 Thunderjet out of a 69 Thunderbird. Supposedly it came from the factory with 325 horse. The guy who i will be buying it off of told me that its bored 30 over has TRW flattop pistons, wolverine cam high output melling oilpump, its been converted to all individual rockers and the pushrods are by Moog performance. He also said that the shop that built the motor says its pushing close to 600 horsepower, does this seem close? It was redone 20,000km ago and the C6 tranny with a stage 2 b&m shift kit was redone last month. What is soemthing like this worth, it does sound to good to be true but he is givin me a guaruntee with it so that helps. What is this worth roughly in Canadian dollars.

 

I am pretty certian that all base 429 where called thunderjets at least all the late 68,69, tbird's I have seen had 429 thunderjets in them. As far as the cost in Canadian with the tranny I am into mine for over $2500 Canadian and most of the labour was me. So I think any where between $1000 and $1500 would be a good buy. But hey some times it's not what its worth but what you can get it for and how hungery the seller is. Eric

 

With the specs you've listed I thing your about 200 HP too high. To get an honest 600 HP out of that engine you'll need all the tricks: 460 or more cubic inch, CJ heads, big roller cam, dominator carb, open headers,
11.5 or higher compression, etc.
Also remember when those engines came from the factory they were rated at gross HP. The 325 HP gross is more likely around 240 HP net (at the rear wheels). Deen

 

Two things that would make me wary: One, the 429 already has "individual rockers" from the factory. There is no rocker shaft such as you'd find on the 390-428 FE motors. In fact, the canted valve design makes fitting the rockers on a single shaft impossible. Perhaps he meant it had been converted to adjustable rockers, which if not done correctly, is a liability not an asset. Two, the horsepower claim is way too high; at the most, you're looking at 400-425hp at the flywheel and it would have to have a pretty stout cam to make that.

 

Yes maybe 400-425 hp the factory hp on a thunderjet was supposed to be 365. Few things to consider the factor pistons are true flatops with 2 eyebrows. Some aftermarket flatops actually have a slightly lower deck highth or a slight dish to them. In either case you loose some compresion. Also after the statement about the rockers. Check the cast numbers on the heads they should be C9VE or maybe C8VE. It kinda sounds to me like they used mid 70s heads and did away with the pedastal mount rockers. If thats the case the true hp may even be less than the origional 365. Good Luck keep us posted. Andy

 

Yeah, the motor sounds pretty gutless at only 400 hp... You could always bring it to me, and I will trade you straight across for my stock 76 460. Where do you live? I may drive there to do the swap.
Mark


https://www.ford-trucks.com/user_gallery/displaythumbnail.php?&photoid=5362&.jpg
Ford started it; Ford will finish it!

 

Well this is what the guy told me, I am gonna get the number for the shop who built it and talk to them. I can get it for $1000 an he will pull the engine and trans for me. Even at 400 horse I am pretty impressed. What other questions can I ask him?

 

The Thunder Jet 429 was in a lot of cars until 1971. It is a strong engine & will propel most vehicles into the 13's & sound like your fathers Oldsmobile while kicking some...

 

Canadian Ranger
Stop by my web site and on ther index page you will the Zip files of my truck.

Click the "Born to be Wild" file to see it run the 1/4.

[font color=red]Dennis

FTE Assistant Administrator
[/font]

[link:www.ford-trucks.com/guidelines.html|Club FTE]

[link: motorhaven.autoanything.com|How YOU Can Support This Site]

http://www.clubfte.com/users/mil1ion/canada_flag_animated.gif

[link:www.clubfte.com/users/mil1ion/Mil1ion.html|My Website,"North Of The 49th"]