engine swap question

bear9820 · Jul 14, 2010

I'm in the process of restoring a 69 mustang. It started life as a I6 and currently holds what is believed to be a 289. I'm thinking about picking up a running 429 for $400. my question is, would the 429 fit in what was once a I6 car or am I biting off too much? I dont see the car being drivable for a few years anyway so time is not an issue. I'm fairly mechanically inclined and have swapped engines before but not for a larger one. the 429 will come with a C6 trans as well. if anyone has any advice or pointers anything would be helpful and welcomed.

2+2GT · Jul 15, 2010

bear9820 said:
I'm in the process of restoring a 69 mustang. It started life as a I6 and currently holds what is believed to be a 289. I'm thinking about picking up a running 429 for $400. my question is, would the 429 fit in what was once a I6 car or am I biting off too much? I dont see the car being drivable for a few years anyway so time is not an issue. I'm fairly mechanically inclined and have swapped engines before but not for a larger one. the 429 will come with a C6 trans as well. if anyone has any advice or pointers anything would be helpful and welcomed.

The 385 Series 429/460 will fit perfectly in the 69. All 69's had the same engine compartment (except the BOSS 429 NASCAR equipped cars). All you need are the special motor mounts and headers. Well, the small details will keep you busy for a while, but the 460 will go right into 67-73 Mustangs.

D.Hearne · Jul 15, 2010

You will need to completely upgrade the suspension, brakes and rearend to be able to handle the big block's power and torque.

bear9820 · Jul 15, 2010

someond did alot of work to the car before i even got it, not sure but was told the car should have a 4 lug, but now has a 5 lug so i have no idea what rear end it has

2+2GT · Jul 15, 2010

bear9820 said:
someond did alot of work to the car before i even got it, not sure but was told the car should have a 4 lug, but now has a 5 lug so i have no idea what rear end it has

You'll need a 9" with a 429. I don't mean maybe.

D.Hearne · Jul 15, 2010

bear9820 said:
someond did alot of work to the car before i even got it, not sure but was told the car should have a 4 lug, but now has a 5 lug so i have no idea what rear end it has

Lift the rear, put it on jack stands. Then get under it and see if you can fit a 9/16" socket and rachet on the two bottom nuts that retain the center section in the housing. If you can, then it's an 8" rear. If you can only get an end wrench on these two nuts, it's a 9".

2+2GT · Jul 15, 2010

Yep- The 9" gearcase overhangs these two bolts:

bear9820 · Jul 15, 2010

so, it currently has an 8in and I found a 9in is $300 a good price for one or should I try to talk the guy down. Im not sure what they are worth as I use to always work on chevy and never tried to build anything with the power I hope to get out of this. I seen these motor mounts RockAuto Parts Catalog not sure if that would bolt up to where the 289 mounts are or if ill need to fab something. Have realized that the shock towers will more than likely need to be cut somewhere. not too much of an issue as I can cut and weld decent enough, I went out to look at the motor the guy is selling and took a few pics.

2+2GT · Jul 16, 2010

bear9820 said:
so, it currently has an 8in and I found a 9in is $300 a good price for one or should I try to talk the guy down.

Have realized that the shock towers will more than likely need to be cut somewhere. not too much of an issue as I can cut and weld decent enough, I went out to look at the motor the guy is selling and took a few pics.

If by $300 for a correct-width 9" axle housing drum to drum, yeah, that's a pretty good price.

You absolutely do not have to cut the towers.

http://www.critesrestoration.com/mustang.htm
http://www.thecurb.org/Webazine/Pits/460ina69/rev-460in69.htm

D.Hearne · Jul 16, 2010

If that 9 isn't a direct bolt in, $300 is about $200 too much. Cutting the shock towers isn't manditory, but if you want to keep your sanity, I would definately do this before doing anything else. I've "been there-done that" with a big block Stang and when I bought my current 77 Comet, that was the first thing I did to it. It's soooooo much nicer to have room for plug changes and header bolt clearance.

bear9820 · Jul 16, 2010

thanks for the links, the 9" im looking at is 58.5" and I think my rear is just a hair over 59" so I'll keep looking for another 9". I wasnt to thrilled about the idea of cutting the shock towers so its a relief that this this step is kind of optional. I do like the idea of stress free and being able to change the plugs when needed. I'll test fit the motor and then decide on the cutting issue. The battery is going to have to be relocated I hear to make room for the motor so I'll start there, order the mounts and get some of this work done before the motor is delivered.

D.Hearne · Jul 16, 2010

If that 9 is that close to yours in measurements (width) and is a leaf sprung unit, buy it. It'll should be be a bolt in (your spring pads are 43" apart) and a half inch difference is nothing, actually if it's narrower, that's in your favor.

bear9820 · Jul 16, 2010

the guy said rotor to rotor I think was 58.5" and I was told mine is 59.25" It already has the disc conversion

D.Hearne · Jul 16, 2010

bear9820 said:
the guy said rotor to rotor I think was 58.5" and I was told mine is 59.25" It already has the disc conversion

It sounds like a late 70's Lincoln Versailles 9". It will be a bolt in swap. Jump on it. Check the gear tag on the front, attached to the rear on one of the center section retainer nuts. Some of these came with traction loc. The gear ratios suck though, unless you're going for a Bonneville speed record, most are 2.50 or 2.75 ratio. But that's easy to change.

bear9820 · Jul 17, 2010

The guy I bought the 429 from said he has a 9" off a 70's t-bird and is just going to give it to me but i'm waiting to get the measurements from him before I drive the 2hrs to pick it up. And yes the other guy said it was a Versailles 9".

D.Hearne · Jul 17, 2010

The T-bird rear will be a coil sprung unit and too wide to work without narrowing. It may also have axles with a 5" x 5 bolt pattern. If he'll give it to you, fine, but I'd grab the Versailles rear regardless.

bear9820 · Jul 17, 2010

I got the casting number off the block that is in the car now and it is believed to be an 85 H.O. 302. probably going to try and sell this motor to help pay for machining on the 429

engine swap question

bear9820

New Member

2+2GT

D.Hearne

New Member

bear9820

New Member

2+2GT

D.Hearne

New Member

2+2GT

bear9820

New Member

Attachments

2+2GT

D.Hearne

New Member

bear9820

New Member

D.Hearne

New Member

bear9820

New Member

D.Hearne

New Member

bear9820

New Member

D.Hearne

New Member

bear9820

New Member

Similar threads

engine swap question

New Member

New Member

New Member

New Member

New Member

Attachments

New Member

New Member

New Member

New Member

New Member

New Member

New Member

New Member

Similar threads

Privacy & Transparency

Privacy & Transparency