swapping engine series

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Sep 20, 2009 | 07:21 AM

lyned

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swapping engine series

Hi guys. I parked my '79 F-100, 400 engine a few years ago due to bad engine (blew out rear main seal on the hwy). Now I'm looking at redoing the truck again. My dad recently passed away and he had a '69 Merc Marquis with a strong 390 2V, body is a little rough. I'd like to redo it also but don't have the cash for both. Tempted to drop the 390 into my truck and was wondering if its worth the hassle or just rebuild the 400. Are the '79 frames drilled to move the motor mounts to accept a different series engine? What else would I need to do? Probably have to go with headers, doubt if I'd find any 390 truck manifolds anymore. Thanks.

Sep 20, 2009 | 03:07 PM

75F350

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Welcome to the site.

Many of the earlier trucks, were available with 360 V8's and the FE series engines shared the same engine mounts, bellhousing patterns etc. The same is true for exhaust manifolds. Some FE engines used different heads that had more exhaust flange bolts, but headers and manifolds are available for these too.
YOu may fine some engine mounts that will bolt right to your truck, but your transmission is different. This means that you will require a new transmission unless you decide to use the car trans also. Then you will just have to use a transmission crossmember that fits. Not a problem right?
Ok, so there are bolt in items available for your truck, and that is no biggie right?
How much will that car be worth after you remove the engine?
COuld it be worth enough to fund your rebuild? Could it fund a 460 swap?
It could be argued that the FE is pretty easy to install, but the 460 is probably easier to install. Since the 335 (351M / 400) series engine and the 385 (429 / 460) series engine use the same bellhousing, you have almost a bolt in swap. You will need engine mounts anyway, so find some that are from a truck with a 460 (2wd only) and run with it.
Easy and common.
That choice is up to you. Again, welcome.

Sep 20, 2009 | 03:23 PM

lyned

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Thanks 75F350. Its an idea I was tossing around. The car might be able to fund my rebuild if left intact, seems they're pretty rare. I am leaning more toward the rebuild. It'll be my project truck over time. I did have the body fixed up and painted about 10 years ago but it wasn't a great job, needs some work again. I want to go through it properly this time so I might as well have a new engine to start with.

Sep 20, 2009 | 03:23 PM

Bowtie_Schmowtie

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From: Western N.C.

Quote:

Originally Posted by lyned

My dad recently passed away and he had a '69 Merc Marquis with a strong 390 2V...

'69 Merc Marquis are listed as having a standard 429-2V...post some pics of the engine so we can figure out if it is indeed a 390.

'68s could be had with a 390 2V as the middle option and a 428 as the top option.

Welcome to FTE!

Sep 20, 2009 | 03:29 PM

Bowtie_Schmowtie

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From: Western N.C.

Also, look at the 4th digit on the VIN.

X- 390 2V

Y- 390 2V high compression

P- 428 4V police interceptor

K- 429 2V

N- 429 4V

Sep 20, 2009 | 03:56 PM

lyned

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Thanks Bowtie. It is a 390, didn't check to see if its "X" or "Y" but I will check that next time, I pulled the heads off quite a few years ago to replace exhaust gaskets and, as par for coarse for these engines, broken exhaust bolts The Marquis Broughams had the 429. My dad's was the base Marquis 2 dr. They had the 390 in the base models 68-69: hxxp://wikicars.org/en/Mercury_Marquis

Sep 27, 2009 | 01:09 PM

docholiday72tx

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From: waco

If you want to put that 390 in to your truck, it's actually pretty simple. You will need the engine perches for a 360 or 390 from an F100 through F250 from 1965 up to 1976. Once you have the correct perches, the engine it self is a direct bolt in. You will need to use a transmision that has an FE bell housing. The transmision cross member will be the same for any transmision, but might need to be moved forward or backward to fit your application. You may also run in to issues with your drive shaft length but it can also be fixed pretty cheap.