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Engine 78 Mustang Ii Engine Swap

  • Thread starter Thread starter 78mIIman
  • Start date Start date Dec 19, 2016

78mIIman

Member
Dec 19, 2016
24
5
13
Chicago
Dec 19, 2016
#1
  • Dec 19, 2016
  • #1
Hey guys,

I'm new to this website, so i'll tell you my LENGTHY story. I recently aquired a '78 mustang II from my uncle, that has been in storage since 1985. It came from the factory with the 4 cyl and a 4 speed, but he slapped a very mild 302 and a c4 automatic in there. His original plans were to throw a chevy 427 (sorry ford guys) with tunnel ram and a beefy 4 on the floor,4.56 gears and a posi, and bracket race the thing.

However, life got in the way (he had kids) and never got the chance to do that, so with a baby on the way, that is when he decided to just put the little 302 in there and daily it for 6 months before storing it. The mustang has 3,500 original miles on it.

Last year, when I was 19, I offered him $$$ for it, and was lucky enough to be able to get it. I very recently rebuilt the 302 with forged rods, hyper pistons, honed the cylinders (what ever little honing there needed to be done), added a weiand street avenger intake, Holley 600 cfm manual choke, hooker headers, and then left the comp came "gripper" cam in there from the early 80's, since it has very little wear. It has D80E heads, which I realize aren't very good performance heads, but I want to save up for a nice set of Aluminum heads or even GT40 heads. (If anybody has them for sale at a reasonable price, let me know!!) So, it should be pushing around 200-230 hp, once I finally start the thing, I'm still in the process of putting the rebuilt 302 in the car. The rear end is a 3.00:1 posi traction. It even has the slotted aluminum American Racing rims and the 30 yr old BF Goodrich Belted T/A tires.

In the future, for "stage 2" of the car, I would love to live my uncle's dream on the 427 chevy in there with the 4 spd and bracket race it. I already have the bare block from him sitting in the basement. Will you be able to fit a BBC in that little engine space? I can see tht there is little room for headers as it is with the 302. I am curious if anyone on this forum has ever done it, or had experience putting a big engine in there.

please let me know what mods need to be done, i know that the oil pan and cross member need to be modified and I will have to use a manual trans for the 427. I'm only 20, and this is my 2nd engine swap in my life. I'm new to the engine swap game so if you could give me some tips it would be greatly appreciated.

here are a few pics of the mII project

Thanks

 

Adieu

Easy there, this ain't a dating site.
20+ Year Stangneter
Mar 7, 2002
9,531
5,187
224
Dec 31, 2016
#2
  • Dec 31, 2016
  • #2
I've thought long and hard about whether to answer this one and if so, how.

Putting a big-block Chevy in there should be possible if you have the fabrication skills, time, money, and the drive to see it through.

It won't be easy, as few have done it (honestly, few of us put big-block Fords in these cars either, for many reasons), but it should certainly be possible.

No matter how much power you're wanting to make, it can be done with a Ford engine. If it's 427cid you want, that could be done using a tall-deck 351W block bored and stroked to 427cid, which would give you a bolt-in engine instead of a lot of fabrication (though there would still be some modifications necessary to the hood and oil pan).

There are IIs out there with 5.4L supercharged Lightning engines, 4.6L Cobra engines, 500+ cid big-block Ford engines, and even a real oddball out there running a 200cid inline six. If those can all be made to fit, you can throw a Chevy engine in there, there's just not going to be a lot of help here since nobody else here has done it. (The only way I'd go Chevy power in my car is to go with a 4.8, 5.3, or 6.0 Vortec from a GM truck with a cam, heads, intake, and turbo for insane streetable power that was reliable, other than that, there'd be no point in my opinion.)
 

RaggedGT

Been here over a DECADE and still no CT
Mod Dude
Jul 20, 2014
4,738
3,187
203
Taylorsville ky
Jan 1, 2017
#3
  • Jan 1, 2017
  • #3
I vote to be waaaaayyyyyy different... but a twin turbo ecoboost 2.3 in it


As far as your questions- @74stang2togo has given you great answer(s)
Time and Money will be your two biggest hurdles in the beginning
 

jozsefsz

15 Year Member
Aug 11, 2013
1,243
332
124
Cleveland OH Area
Jan 1, 2017
#4
  • Jan 1, 2017
  • #4
I agree with the above fully - - anything can be done, but a BBC into a II is not an engine swap. It's more of a custom fabrication of the full front-end. I'd expect you'll be moving frame-rails, building a firewall, chopping the trans tunnel, if not going fully tubular. And that amount of weight on the front of a II is going to kill its ability to move and turn, some of the primary benefits of the II chassis.

Lots of high-power options staying Ford (including putting some Forced Induction on what you already have), but if you'd like to go Chevy, why not consider an LSx swap? I believe someone on this forum was doing one, and the physical fit seemed very good. Huge aftermarket support, tough blocks, light-weight, and relatively low cost. It might still be living your uncle's dream in-spirit with a little bit of newer tech.
 

78mIIman

Member
Dec 19, 2016
24
5
13
Chicago
Jan 17, 2017
#5
  • Jan 17, 2017
  • #5
Thanks for the reply guys, really appreciate it. I will definatly consider what everyone mentioned about the BBC and other options as well. Its just I have the 454 bare block from 1969 just sitting and waiting, which is why I was considering it. However, for now, I want to enjoy the 302 and save up for a Weiand supercharger, maybe for next year.
 
Reactions: Marcolivier
I

Ih8chrome

Member
Mar 21, 2017
3
1
13
Mar 21, 2017
#6
  • Mar 21, 2017
  • #6
New here as well recently aquired a 68 thunderbird donor car with a 429. For 400 bucks so I'll be attempting this with my 76 posting this so I get notifications on the thread thanks
 

RaggedGT

Been here over a DECADE and still no CT
Mod Dude
Jul 20, 2014
4,738
3,187
203
Taylorsville ky
Mar 21, 2017
#7
  • Mar 21, 2017
  • #7
Ih8chrome said:
New here as well recently aquired a 68 thunderbird donor car with a 429. For 400 bucks so I'll be attempting this with my 76 posting this so I get notifications on the thread thanks
Click to expand...
Start a New thread on your build-many will pop in to check it out,offer advice/and start useless banter
 
Reactions: LILCBRA, Ih8chrome and Adieu
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