ford 302 to inline six conversion
Posting Guru
Joined: Feb 2002
Posts: 1,712
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From: Atlanta, Georgia, USA
I can't find and don't care to spend more time researching how picky they are on the inspection. Out here, an engine swap like this is going to get the red flags up and subject you to an even more detailed inspection and approval process. On the other side, if you don't get everything hooked up right, or don't match the OEM emissions specs, you may not pass.
FWIW, get another 302 and put it back the way it was. I'd tell you the same thing if you had a 300.
Good luck with whatever you decide, but watch yourself, you don't want to end up parked without registration or having to spend more money on this than necessary.
The reason I think you'll get away with it at any inspection is because in your '90, the I-6 was a factory option. They'd have to pry into the VIN to compare what it was built with an what it has now. Again, it's worth looking into because would be a serious failure if you couldn't get it registered! Still, it's not like you're showing up with a 429 big block and a pair of Holley Double-Pumpers sitting on top of a tunnel ram manifold through a hood cut-out.
The inspector would have to a (insert your favorite insult) to fail you with that swap, because it would be legal in every state I've lived in, including the King Kong of ridiculous gearhead-hater laws, California.
Super Moderator
Joined: Apr 2004
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I will definitely agree with this if your state goes crazy with the inspection. I my experience however, I've never had an inspection done by somebody who would have 1) caught the engine swap or 2) cared to throw the flag on it.
The reason I think you'll get away with it at any inspection is because in your '90, the I-6 was a factory option. They'd have to pry into the VIN to compare what it was built with an what it has now. Again, it's worth looking into because would be a serious failure if you couldn't get it registered! Still, it's not like you're showing up with a 429 big block and a pair of Holley Double-Pumpers sitting on top of a tunnel ram manifold through a hood cut-out.
The inspector would have to a (insert your favorite insult) to fail you with that swap, because it would be legal in every state I've lived in, including the King Kong of ridiculous gearhead-hater laws, California.
The reason I think you'll get away with it at any inspection is because in your '90, the I-6 was a factory option. They'd have to pry into the VIN to compare what it was built with an what it has now. Again, it's worth looking into because would be a serious failure if you couldn't get it registered! Still, it's not like you're showing up with a 429 big block and a pair of Holley Double-Pumpers sitting on top of a tunnel ram manifold through a hood cut-out.
The inspector would have to a (insert your favorite insult) to fail you with that swap, because it would be legal in every state I've lived in, including the King Kong of ridiculous gearhead-hater laws, California.
Post Fiend
Joined: Jan 2007
Posts: 7,021
Likes: 4
From: Almost Heaven
Hello my friend
Baseline carb'd: 300 @ 255 ft lbs, 302 @ 230 ft lbs
EFI: 300 @ 265 ft lbs and the 302 @ 270 / 280 ft lbs.
The 302 never made 210 ft lbs that I'm aware of.
Baseline carb'd: 300 @ 255 ft lbs, 302 @ 230 ft lbs
EFI: 300 @ 265 ft lbs and the 302 @ 270 / 280 ft lbs.
The 302 never made 210 ft lbs that I'm aware of.
Cargo Master
Joined: Sep 2010
Posts: 3,191
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From: SW Washington
Post Fiend
Joined: Jan 2007
Posts: 7,021
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From: Almost Heaven
I wonder where John got those numbers from?
The 302 and 300 have always put out decent torque for their size. Even the 350's back then were only putting out 10 more ft lbs of torque. The Ford engines were putting out good pulling power for their size.
And heck the 300 is just a bored and stroked 240.
So, basically a beefed up 240 I6 was giving the Chevy 350's a time in the torque department.
Cargo Master
Joined: Sep 2010
Posts: 3,191
Likes: 2,007
From: SW Washington
I wonder where John got those numbers from?
The 302 and 300 have always put out decent torque for their size. Even the 350's back then were only putting out 10 more ft lbs of torque. The Ford engines were putting out good pulling power for their size.
And heck the 300 is just a bored and stroked 240.
So, basically a beefed up 240 I6 was giving the Chevy 350's a time in the torque department.
According to Wikipedia, "The 300 cu in (4.9 L) six was added for the F-series in 1965. It was essentially a 240 cu in (3.9 L) with a longer stroke. The two engines are nearly identical; the differences are in block dimensions, combustion chamber size, and the rotating assembly."
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Senior User
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One important aspect that is being ignored, is RPM of torque output. The 302 will put out peak torque at a much higher rpm, because of bore vs stroke. The 302 has a much shorter stroke in comparison to the bore diameter (about 4"x3"), while the 300 bore vs stroke is essentially square. Almost 4"x4" per cylinder. Essentially, the 300 will have a much smoother, earlier torque output vs a 302, which will require more RPMs to make the same torque. This is stock for stock of course. This also means the 6 is at a disadvantage for horsepower, which is essentially rate of torque output. Does this make either a BETTER engine? It comes down more to what the owner needs
Post Fiend
Joined: Jan 2007
Posts: 7,021
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From: Almost Heaven
Thanks Gigger! Awful nice of you to say. Betsy is my baby. She's like a horse to me.
91chevywt, Kapusta is right. It really just depends on the gearing.
The EFI 300 makes it's peak torque at 2,000 RPM. The 302 will make peak torque around 2,400 RPM. Not that huge of a difference.
The carb'd 300's make peak torque much lower, around 1,400 RPM.
The 300 really is more like a diesel. It's deffinately a working engine. Afteral, the airport tugs use 300 I6 engines with a C6 transmission with 1st gear locked out.
So, yes. The 300 is a better work-truck engine. But that doesn't mean the 302 can't pull or haul! It's just much happier going fast and blowing the doors off a dumb kid's Chubby or Rum truck.
91chevywt, Kapusta is right. It really just depends on the gearing.
The EFI 300 makes it's peak torque at 2,000 RPM. The 302 will make peak torque around 2,400 RPM. Not that huge of a difference.
The carb'd 300's make peak torque much lower, around 1,400 RPM.
The 300 really is more like a diesel. It's deffinately a working engine. Afteral, the airport tugs use 300 I6 engines with a C6 transmission with 1st gear locked out.
So, yes. The 300 is a better work-truck engine. But that doesn't mean the 302 can't pull or haul! It's just much happier going fast and blowing the doors off a dumb kid's Chubby or Rum truck.
Senior User
Joined: Sep 2009
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From: Rocky Mountians
One important aspect that is being ignored, is RPM of torque output. The 302 will put out peak torque at a much higher rpm, because of bore vs stroke. The 302 has a much shorter stroke in comparison to the bore diameter (about 4"x3"), while the 300 bore vs stroke is essentially square. Almost 4"x4" per cylinder. Essentially, the 300 will have a much smoother, earlier torque output vs a 302, which will require more RPMs to make the same torque. This is stock for stock of course. This also means the 6 is at a disadvantage for horsepower, which is essentially rate of torque output. Does this make either a BETTER engine? It comes down more to what the owner needs
They are tough engines.
Im not sure how many people will believe me but on my last road trip I was driving 65mph, all highway, with my 300EFI, M50D R-2, 4x4 with manual hubs, standered cab long box, loaded down with huning gear.
And I pulled a constent 22mpg.
I am also running a slightly over sized tire. 31x10.50 mud kings, so my mileage was slightly better.
I have pulled a 21ft boat, and moved a 31ft toy hauler around out property with my 300.
That engine will never leave my truck