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How much time to replace a 318 w a 440 68 coronet

Moparnocar

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I have a buddy looking to put a 440 and trans into a 68 Coronet that has a 318 auto.

I know there are a ton of "ifs". But whats a ball park time to do this? Do i need a different k member, mounts, torsion bats?

Thanks
 
About 2 hours... if you have the parts!

The engine and trans will bolt in with the right brackets. The driveshaft will need to be sourced if you don’t have an original. I believe you can shorten a 318/904 one. Obviously a lot of little things like wiring and the cooling will need to be addressed.

If you go aluminum heads, intake, battery in trunk... you can run the 318 T bars.
 
Will the original rearend survive that much power applied? Seems like a pretty big step up.
 
What is the level of wrenching competence? It can be done in a day if you have all the parts and tools sitting there.
Since you are asking about what fits then it will be impossible to tell you a time frame.

the K frame is fine. You need the right engine brackets to fit the k frame. You can use the torsion bars, will not corner very well. Would,be better with bigger bars bit not necessary right away. You need a BB 727 with a long tailhousing for a car. You need a different driveshaft. What rear axle is in the car now? 8 3/4 is what you want. You need a bb PS pump. You can use the SB radiator but the lower hose connection is 1.5” instead of 1.75”
 
All ‘68 318 B bodies had the 8 3/4 I believe.
 
All ‘68 318 B bodies had the 8 3/4 I believe.
No they don’t, that’s why I asked him. Most did, but not all did, it’s something to be aware of in this situation.
 
No they don’t, that’s why I asked him. Most did, but not all did, it’s something to be aware of in this situation.

All the ones I saw did. 318 not 273.
 
Mine does, and sure grip.

The ‘68 Sport Satellite has the 318 standard. I never saw one without an 8 3/4 under it or any 318 car from ‘68. The Wagons all got the 8 3/4, but it was about an inch wider.
 
About 2 hours... if you have the parts!

The engine and trans will bolt in with the right brackets. The driveshaft will need to be sourced if you don’t have an original. I believe you can shorten a 318/904 one. Obviously a lot of little things like wiring and the cooling will need to be addressed.

If you go aluminum heads, intake, battery in trunk... you can run the 318 T bars.
I'm an experienced wrencher, my body is not shot...yet.

2 hrs? I think ive pulled one in 2 hrs lol. So, if stuff bolts in, nothing crazy different? I've only swapped big blocks. Definitely loking at rear end
 
I'm an experienced wrencher, my body is not shot...yet.

2 hrs? I think ive pulled one in 2 hrs lol. So, if stuff bolts in, nothing crazy different? I've only swapped big blocks. Definitely loking at rear end

If the 5th digit in your VIN is “F”. You will have an 8 3/4 rear.
 
If you are a good wrenched than it is a pretty easy job. You just need the correct pieces to change it over.

Forget all this talk and look at the rear axle to see what the car has. It is something to be aware of because you don’t want to make or scrounge a driveshaft for the smaller rear axle.
 
I say give yourself a weekend as long as you have everything. If you have a 727 behind the 318 you will not need a new driveshaft.

A 7 1/4 rear will hold up if you don't beat the hell out of it. My buddy had a 72 b-body that had a 7 1/4 and 318 stock. We dropped in a 440 with 500 HP and drove it easy until until he found a 8 3/4. Because he was that kind of guy he then wanted to try to explode the 7 1/4 for the fun of it. He had 10 inch L-60's on the back and with the one wheel peel he only succeeded in burning up the tires. If he had sticky tires on the back it probably would have blown.
 
If you are a good wrenched than it is a pretty easy job. You just need the correct pieces to change it over.

Forget all this talk and look at the rear axle to see what the car has. It is something to be aware of because you don’t want to make or scrounge a driveshaft for the smaller rear axle.

You do realize the 318 was an option on the ‘68 B body, except the Sport Satellite and Coronet 500. The 8 3/4 was part of the package. That changed for ‘69. They you started seeing the 7 1/4 rear under 318 cars.
 
Will take a lot longer than expected, especially if engine has been in awhile and if you have never done it before.

Make sure you have a couple good jacks and jack stands and put a block or rim under car for extra insurance if car falls. Safety is one area not to cheap out on. Saws-all or torch for bolts that won’t come out.
 
@440 PHIXX

what I realize is that they all didn’t come with a 8 3/4 or a 727.

I also realize he claimed a Satellite 318. Not a Sport Satellite.

I also realize that many people ASSume a 273 is a 318.

I also realize the car is now 54 years old and people swap parts.

I also realize that when people ask help it’s good to mention everything.

Please rear what post #6 really says, not what you read into it.

So I advise him to make sure he has an 8 3/4

that is all. Have a great day.
 
@440 PHIXX

what I realize is that they all didn’t come with a 8 3/4 or a 727.

I also realize he claimed a Satellite 318. Not a Sport Satellite.

I also realize that many people ASSume a 273 is a 318.

I also realize the car is now 54 years old and people swap parts.

I also realize that when people ask help it’s good to mention everything.

Please rear what post #6 really says, not what you read into it.

So I advise him to make sure he has an 8 3/4

that is all. Have a great day.

It came off as if you were arguing that I was wrong. Sorry if I took it that way. I’ve only seen 904’s behind the 318’s in ‘68 passenger cars... not police. But I would be interested in seeing a broadcast sheet specifying a 318 and a 7 1/4 rear on any ‘68 B body. Including the Charger. I realize rears get changed. That didn’t seem to be what you were implying when you said I was mistaken.
 
I have a buddy looking to put a 440 and trans into a 68 Coronet that has a 318 auto.

I know there are a ton of "ifs". But whats a ball park time to do this? Do i need a different k member, mounts, torsion bats?

Thanks

I owe you an apology as well... I didn’t mean to turn your thread into a pissing contest. Most of the parts you’ll need are bolt in. If it were me, I’d upgrade to a 26” radiator. The 22” will be OK, but the 26” is added insurance in traffic in the summer.
 
Not much in common between the two engines and drivetrain. It would take a experienced guy a day or so if he had all that was needed for the swap. All the systems need replaced or modified.
 
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