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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

Mod (4v) Swap Questions

  • Thread starter Thread starter sen2two
  • Start date Start date Sep 5, 2016

sen2two

I've been lubing and pulling it all morning
5 Year Member
Jul 18, 2013
396
58
59
Sep 5, 2016
#1
  • Sep 5, 2016
  • #1
I was offered a mod motor long block in a parts trade. It's a teksid aluminum block from a 96-98 Mark 8 I believe. I have always wanted to do this, but only if a motor fell into my lap. Well, now it kind of has. But I havn't done any real research on the swap.

I use to do everything the hard way and do little by little as I wire, fab, and research and get it done. But these days, time is short. I don't have the opportunity for long down time like I use to. So, is there some sort of "kit" to swap in a 4v to my Fox?

The only thing I'm actually concerned about is the wiring. This always eats up ALL my time. As I am NO wiring guru. So I have to wire some, research wire some, repeat, to get it working. I would love there to be a plug and play harness.

Is there so sort of how-to real world parts list like there is for the 351 swap...?
 

MikeH686

Mine is only two inches though.
10 Year Member
Oct 11, 2011
2,843
1,753
184
Waldorf, MD
Sep 6, 2016
#2
  • Sep 6, 2016
  • #2
Ditch the wiring for the 4v and put an aftermarket efi system on it
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,287
17,980
224
Massachusetts
Sep 6, 2016
#3
  • Sep 6, 2016
  • #3
Do you have a transmission for it? headers? It's a project for sure, and not one that can be done in a weekend. The mark 8 motor has a different upper manifold than the Cobra, so you'll need to either figure out something for the rear mounted throttle body, or purchase a 96-98 cobra intake and install it on the mark engine.
 

hoopty5.0

mechanicus terribilis
15 Year Member
Dec 14, 2010
7,794
6,946
214
SW Houston
Sep 6, 2016
#4
  • Sep 6, 2016
  • #4
Mod motors are terds without boost.
 

sen2two

I've been lubing and pulling it all morning
5 Year Member
Jul 18, 2013
396
58
59
Sep 6, 2016
#5
  • Sep 6, 2016
  • #5
Mustang5L5 said:
Do you have a transmission for it? headers? It's a project for sure, and not one that can be done in a weekend. The mark 8 motor has a different upper manifold than the Cobra, so you'll need to either figure out something for the rear mounted throttle body, or purchase a 96-98 cobra intake and install it on the mark engine.
Click to expand...

No intake manifold on this motor. So getting a Cobra one or aftermarket would be the plan.

I would only have the long block for now, and start gathering parts if I went for it. I normally gather all needed parts before starting projects now. I've learned from past cars not to start in on something without knowing what I need and having it ready.

hoopty5.0 said:
Mod motors are terds without boost.
Click to expand...

That's the plan.... I've owner about 30 cars now. I would say 85-90% of them either started off Turbo, or ended up with a Turbo. Or two....
 
Reactions: hoopty5.0

sen2two

I've been lubing and pulling it all morning
5 Year Member
Jul 18, 2013
396
58
59
Sep 6, 2016
#6
  • Sep 6, 2016
  • #6
MikeH686 said:
Ditch the wiring for the 4v and put an aftermarket efi system on it
Click to expand...

From what I've been reading the stock 4v harness installs easy. But I havn't found any real information. Just people saying it's easy to wire in. No details yet.

I would much rather get a plug and play harness. I've built my own swap harness before. And dewired/wire tucked others. I hate it.... But I also hate wire clutter in the engine bay.
 

Mr. Rustypwnz

Advanced Member
Jun 1, 2005
1,761
63
69
indianapolis/ valdosta ga
Sep 6, 2016
#7
  • Sep 6, 2016
  • #7
sen2two said:
From what I've been reading the stock 4v harness installs easy. But I havn't found any real information. Just people saying it's easy to wire in. No details yet.

I would much rather get a plug and play harness. I've built my own swap harness before. And dewired/wire tucked others. I hate it.... But I also hate wire clutter in the engine bay.
Click to expand...

Holley efi all the way.
 
Reactions: MikeH686 and Davedacarpainter

TOOLOW91

If you're the village idiot what's that make me?
20+ Year Stangneter
Nov 29, 1999
8,498
8,751
234
S.I.NY
Sep 6, 2016
#8
  • Sep 6, 2016
  • #8
Put a holley on it. Throw some boost at it .
 
Reactions: MikeH686
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