Adding a 429 Thunder Jet to a 71 Mustang

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Joined
Jul 24, 2018
Messages
108
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3
Location
Northville, MI
My Car
70 Maverick Grabber w/351W & Toploader
71 Mach 1 w/ 429 & T56
Hi guys - another question - 

In process of taking a plain-jane 71 Fastback - and converting it into a 429 Mach 1.  Project is pretty far along, and towards the end of last year, we fitted the 429 Thunder jet into the bay prior to making the headers, custom mount brackets, etc.  The overall package includes an SFI bell housing mated to a Tremec T-56 6 speed.  The process of fitting this combo to the car involved us making a small rolling jack stand, getting everything into the best position we could before fabbing the mounts and headers.  Problem was - when we dropped the repo rain-catcher (w/seal)  onto the carb, the hood would not sit down fully in the rear (front latched no problem).  This engine currently has the stock heads, intake and carb, so I'm thinking this should be pretty close to what the final combo will be with the motorsport heads, Edelbrock intake etc.  There is about .5" of clearance between the stock oil pan and the crossmember, so, I don't want to cheat that anymore.  The combo is dead nuts perfect in the X and Y direction - made sure of that - it lines directly with the center of the plenum.  I have not tried to work the seal to see if that will alleviate the issue.

Several questions to this one:

- Has anyone else seen this issue when mating a "Thunderjet" to a 71 Mustang?

- Were the oil pans different for mustangs - ie. shallower (I believe the blocks were identical)?  This engine is out of a T-Bird.

- What has anyone else done to correct this?

Barring any stunning revelations, I'm likely going to have to work the seal and possibly even have to modify my rain catcher to sit deeper on the carb.

Thx..

 
Just a thought, is the air cleaner 429 specific or the standard 351 Ram Air type ? I believe the 429 type, which are not reproduced and are very difficult to obtain. Your only option maybe to modify your present unit.

Thanks, Jay.

 
The angle of the engine can also play a role. What is the angle?

The magnum transmission is much taller and i assume you had to modify the tunnel to allow it to fit.

Sent from my SAMSUNG-SM-G930A using Tapatalk

 
Just a thought, is the air cleaner 429 specific or the standard 351 Ram Air type ? I believe the 429 type, which are not reproduced and are very difficult to obtain. Your only option maybe to modify your present unit.  

Thanks, Jay.
...well I'll be.  Thanks for this tip cleveland coupe.  When I bought the catcher, I was told it would fit any ram air and they were all the same.  However, this time around I drilled down another level and called Dynacorn.  They were able to confirm - after a few checks - that this rain catcher is in fact for a 351 application.  They were also able to confirm that they do not make one for a 429 application.  and since I see the same PN from almost everyone, leads me to believe this is the only one on the market.  

Looks like I'm modifying the one I have!

 
The angle of the engine can also play a role. What is the angle?

The magnum transmission is much taller and i assume you had to modify the tunnel to allow it to fit.

Sent from my SAMSUNG-SM-G930A using Tapatalk
I set it up so that my driveline would maintain 1-3 degrees with a 2 pass loading condition.  With that set-up, the tunnel sheet metal was pretty good, but the one cross member had to be modified.  I think the fit's about as good as I can get it at this point.

 
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