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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

4.2L 255 from 81 Mustang

  • Thread starter Thread starter ³à³
  • Start date Start date May 3, 2004
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The Shape

Founding Member
Jan 11, 2002
2,224
8
49
East ARKANSAS Delta
May 7, 2004
#61
  • May 7, 2004
  • #61
Good luck with it man. I had a friend with this engine in a Fairmont. I never drove it so I have no idea how they feel, he did install an a set of stock 5.0 headers on it that I had lying around.
 
M

maddog11

New Member
Jul 13, 2003
54
0
0
Ameliasburgh, ON, Ca.
May 7, 2004
#62
  • May 7, 2004
  • #62
Good to hear it turned over, now for how it feels driving it! Like I said it isn't like a 302 , BUT driving it on the highway was a whole other story!!!!! Let us know how it goes!!!! I would like to see what the 255 will do, now that some parts are available!
 

dvs bullet

New Member
Feb 20, 2004
326
0
0
Ontario, Canada
May 7, 2004
#63
  • May 7, 2004
  • #63
I did that conversion my self a long time ago, it was a good learning experience. It was a sled, I popped the motor in 2 weeks, then went and bought a gt 5.0, the only saving grace was that it was geared really steep. good luck but I don't think it'll be what you think it will. Like I said it's good experience though.
 
³

³à³

New Member
Apr 16, 2004
88
0
0
nowhere
May 8, 2004
#64
  • May 8, 2004
  • #64
OK we worked late on getting the thing running. It runs and sounds crisp with the cam in it. Not sure of the exact specs but it sounds good.
Went down the road in it and its ALOT different than the 2.3L. I know I know it isnt a beast or anything and will prolly lose to 5.0s and all but it sounds so awesome. I hate to have to install exhaust on it today
It pulls evenly and will bark the tires in 2nd pretty easily. Id guess it will run in the 15s and with that I am happy
 

dastang2

Active Member
Dec 11, 2003
2,020
0
46
tx
May 8, 2004
#65
  • May 8, 2004
  • #65
watch the rearend and tranny when you do those burnouts and scratches
 

NeVeRLiFt

Founding Member
Sep 29, 2002
63
0
6
In the shadows of the Megacorporations
May 8, 2004
#66
  • May 8, 2004
  • #66
Get the heads ported and polished by someone that knows what they are doing and get a good valve job. Get some roller rockers if you can also this will help you pickup 15-45hp depending on the cam and intake. I highly recommend a set of long tube headers.

Goodluck and hope it lasts you.
 

jwzg

Member
Apr 6, 2004
237
0
16
Prattville, AL
May 8, 2004
#67
  • May 8, 2004
  • #67
What kind of exhaust did you go with? My hope is that you went with something you can grow into (2 1/4" or greater). I agree with the dastang2. Get the engine running well and take it easy until you can get enough money to get your drivetrain where you want it. BTW, don't worry about times too much. I take it you are still pretty young, so you'll be better off just learning how to drive the thing smooth and safe for now.
 
D

Demon440

New Member
Jan 2, 2002
15
0
0
May 8, 2004
#68
  • May 8, 2004
  • #68
Do you have any pictures? I would like to see what the engine looks like in there.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
May 8, 2004
#69
  • May 8, 2004
  • #69
It looks just like any other carb'd small block Ford in a Stang. Except it's appears smaller because of it's inferiority complex.

Nice job on moving forward with what you wanted to do --- enjoy your handiwork.
 

85_SS_302_Coupe

it sucks (I know) to be on the receiving end
15 Year Member
Nov 11, 2003
6,945
1,598
223
Northern KY
May 8, 2004
#70
  • May 8, 2004
  • #70
STROKE IT AND BLOW IT BOY!!! WHOOOO WHOOOOOOO!!!!!






sorry i couldnt resist..
 

The Shape

Founding Member
Jan 11, 2002
2,224
8
49
East ARKANSAS Delta
May 8, 2004
#71
  • May 8, 2004
  • #71
Congrats man glad you got it going.
 
³

³à³

New Member
Apr 16, 2004
88
0
0
nowhere
May 8, 2004
#72
  • May 8, 2004
  • #72
Put about 50miles on it today
Looks like my 4cyl radiator is too small. It wants to run warm at stoplights. Im happy so far
 

jwzg

Member
Apr 6, 2004
237
0
16
Prattville, AL
May 8, 2004
#73
  • May 8, 2004
  • #73
Congrats from here as well. Remember, whatever you do from now on, make sure you buy parts that will help you grow into a larger motor.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
May 8, 2004
#74
  • May 8, 2004
  • #74
No doubt the radiator will need to be upgraded, but running warm at low speed usually just means you're not moving enough air across the radiator - usually a fan/shroud issue.
 
³

³à³

New Member
Apr 16, 2004
88
0
0
nowhere
May 9, 2004
#75
  • May 9, 2004
  • #75
Yeah I understand. We just used the stock 4cyl setup with the small electric fan. Looks like we will go with dual 12 fan setup and swap to a V8 radiator
 
B

blk9450

Founding Member
Jan 31, 2002
1,507
0
0
your moms bed
May 9, 2004
#76
  • May 9, 2004
  • #76
4cyl and 8cyl stangs had different radiators? maybe this is why i run hot...
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,253
17,937
224
Massachusetts
May 9, 2004
#77
  • May 9, 2004
  • #77
4-bangers without A/C got 1-core radiators

4-bangers w/ A/C and 5.0's got 2-cores


The hard parts done. I would worry less about modding the motor and more about getting everything else up to snuff in terms of drivetrain, rear end, brakes and so on.

Keep your eye open for a good deal on a 302 or 351. Get one, toss it on a stand and build it to the hilt. Then switch motors and you are all set to go.

Can prob snag a good 302 HO out of a Mark 7 around here for 200-300. Hell, even town cars and thunderbirds have the same bottom end.
 
³

³à³

New Member
Apr 16, 2004
88
0
0
nowhere
May 9, 2004
#78
  • May 9, 2004
  • #78
Yep I have my first race today
80ish V6 Camaro that I raced with the 2.3 wants to try me. Im sure I will waste him unlike last race where I got creamed. We race in an hour on the old airport strip.
I still have no clue where to shift this thing at?
 
J

Js5ohLX

Member
Apr 5, 2004
287
0
16
Ohio
May 9, 2004
#79
  • May 9, 2004
  • #79
if it's a 2.8 multi port, he'll stomp you. If it's carbed, you'll stomp him.
 

CarlsV6

Founding Member
Sep 27, 2001
400
0
0
Stafford, VA
May 9, 2004
#80
  • May 9, 2004
  • #80
Glad to hear you got it in and got it running good. Be easy on that 7.5 rear though.
 
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