4.2L 255 from 81 Mustang

93 teal terror · May 3, 2004

Well not to shoot you down, but heres a quote form one of the many mustang books out there....."The 4.2-liter V8 found in this series of mustangs is totally worthless for high performance modification. Do not waste the time or money trying to modify this engine"

On a side note, it will leak from the rear main seal as it has a 2 piece rear main seal. Its hard enough to get a one piece to seal right much less a 2 piece

blk9450 · May 3, 2004

³à³ said:
My dad didnt even know they existed

³à³ said:
My dad has a customer that has one in a 80 F100 and it runs like a scalded dog.

dude you are obviously a moron, you shouldnt have a mustang, you should be riding the short bus

NKau · May 3, 2004

blk9450 said:
dude you are obviously a moron, you shouldnt have a mustang, you should be riding the short bus

Good constructive criticism there; prick. To the original poster, cut your losses and try and resell that engine. Chalk it up as a lesson learned and move on. I'm sure you'll research other parts purchases much harder after this Trust me, lots of others have dropped a lot more money on parts only to find out later they weren't going to do the job.

blk9450 · May 3, 2004

NKau said:
Good constructive criticism there; prick. To the original poster, cut your losses and try and resell that engine. Chalk it up as a lesson learned and move on. I'm sure you'll research other parts purchases much harder after this Trust me, lots of others have dropped a lot more money on parts only to find out later they weren't going to do the job.

hey no problem there tough guy, by the way, you are using someone else's avatar.

³à³ · May 3, 2004

My dad always thought it was a 302 in the truck until now. The guy seen the motor in the garage and asked about it. My dad started talking about it when the man said that was in his truck. My dad paid for it so no money out my pocket
And what is a short bus?

hllon4whls · May 3, 2004

I am not sure what will fit from a 289/302 onto that motor. Edelbrock says that the performer will not fit.
http://www.edelbrock.com/automotive/man_ford_289.html
It looks like it is the same cam according to this.
http://www.lazercams.com/FD8Erly_LateFirOrderApp.html

As far as that little motor running like a scalded dog in a F100, I doubt it. Too small, too much of a smog motor. That motor is to ford what a 305 is to chevy.

If you did not want everyones advice, you shouldnt have asked. Also, $500 is a lot of money for a used non rebuilt engine. Most junkyards have them in the 350 range with a 30 day warranty. You used to be able to get a pep boys rebuilt motor for around $600 for a V8. I dont know what they go for now.

³à³ · May 3, 2004

It is freshly rebuilt but to stock specs with 2bbl carb.
We are changing the cam and intake to a 4bbl.
I know the truck will spin the tires through 2nd gear and bark 3rd. Everyone thinks/thought it was a 302

I do appreciate the responses but was hoping to find someone that had souped one up to speak from expierence instead of speculation or magazine articles.

maverick0716 · May 3, 2004

When you get the engine in there you should post on here to let us know how it went. I'm curious anyway.

³à³ · May 3, 2004

I sure will. It should be done by no later than Sun night. We are actually pulling the 2.3 tomorrow night. May get started on the install sooner. Cam is already purchased but I gotta find an intake. Already have a 850 Holley for it.

³à³ · May 3, 2004

that should read 580 Holley not 850. Im not that stupid

³à³ · May 3, 2004

Is my T5 gonna work behind this motor? What about my rearend? Is it gonna explode with first dump of the clutch? Oh my I have alot of questions now

CarlsV6 · May 3, 2004

Not the path I would have chosen but good luck none the less, be sure to post up how things go with the swap.

cmozez · May 3, 2004

My boy, you just bought yourself a lesson.

dastang2 · May 3, 2004

you don't know what the tard car is, AKA the short bus. i have 2 HO's here that many here have already seen the ads. 100 each for the whole thing.. one is an 87 and one is a 91

bgjohnson · May 3, 2004

that's a damn good deal, 100 bucks man, I'd seriously consider it. but if the 4.2 is rebuilt and fresh you might as well go with it and be one of the first people to use it as a performance option. I kind of admire you trying to use somthing like that, and your tranny and rear end might go out. I have no idea what power it will put out(170-180 maybe) the horse power won't kill you it will be the torque that does your driveline in. and as for the truck being able to bark them in third, don't forget that a truck is geared like a truck, not a car. but with a 2.3 tranny I believe they are geared higher than a t-5 tranny. I just hope you don't break anything and I don't think the 2.3 tranny will hook up to the 4.2 motor, but I'm just guessing. good luck with all the stuff, you are lucky it is carbed EFI would be a bitch!

dastang2 · May 3, 2004

i wonder if you can put a 302 crank, rods and heads to make it a 302

SilikonBlu · May 3, 2004

Courtesy of Mustang Monthly

"It may interest you to know that 1980 was the first year the Mustang received halogen headlamps. It was also the first year the Mustang ever had an optional V-8 smaller than the 260ci small-block available the Mustang’s first year. The de-cubed 255ci small-block was a weak attempt by Ford to develop a V-8 that would offer better fuel economy than the 302 it replaced. In fact, the 302 wasn’t even available in the Mustang in 1980-’81. Ford took the 302’s three-inch stroke and married it to a smaller 3.68-inch bore. But this is where the similarity ends. The 255 had different cylinder-head porting designed to improve low-end torque and reduce emissions. Buff magazines of the period experimented with the 255 without much success. It was never considered a performance engine."

Good luck with your swap - regardless of the performance outcome it will be a good learning experience for you on the Fox platform...

SPEED FREAK · May 4, 2004

This is something I never thought I would read here..... I am however really interested in the outcome. A 302 would deffinetly have been a better starting point however this thing might work with..... I dont know its never been done . Good luck and keep us posted. That v8 will not have the power stock to hurt either your t5 or your rear end. Just be sure to get the proper pilot bushing. See if you can at least locate some e 7 heads as they will be a billion times better than whatever came on that motor stock. of course providing they are interchangable.

Good luck.

hllon4whls · May 4, 2004

³à³ said:
It is freshly rebuilt but to stock specs with 2bbl carb.
We are changing the cam and intake to a 4bbl.
I know the truck will spin the tires through 2nd gear and bark 3rd. Everyone thinks/thought it was a 302

I do appreciate the responses but was hoping to find someone that had souped one up to speak from expierence instead of speculation or magazine articles.

What sort of intake did you find to fit? DOES a 289/302 intake infact fit properly ? Including port alignment?

³à³ · May 4, 2004

Nope the 302 intake does NOT fit. We found that out today. Not sure what we are gonna do with the intake selection now

Good note is the 2.3 is out and gone already. One of dads friends wanted to replace a motor in a Ranger that has over 400K miles. I was like DAYUMMMM 400K?????? Must be tough but still so weak.

The motor will be placed into the car tomorrow. The intake will be sorted out ASAP.
Would a 2bbl to 4bbl adapter kill performance on it?

4.2L 255 from 81 Mustang

93 teal terror

blk9450

NKau

blk9450

³à³

New Member

hllon4whls

BANNED

³à³

New Member

maverick0716

³à³

New Member

³à³

New Member

³à³

New Member

CarlsV6

cmozez

Member

dastang2

Active Member

bgjohnson

dastang2

Active Member

SilikonBlu

New Member

SPEED FREAK

hllon4whls

BANNED

³à³

New Member

Similar threads

4.2L 255 from 81 Mustang

New Member

BANNED

New Member

New Member

New Member

New Member

Member

Active Member

Active Member

New Member

BANNED

New Member

Similar threads

Privacy & Transparency

Privacy & Transparency