Roler Motor Vs. Flat Tappet 302?

[broncoitis]

I have a motor out of an 89-92 Mustang I believe sitting on an engine stand that needs to be rebuilt or freshened up at the minimum. It has 100K on it.

Currently running an older Flat tappet motor in the truck from a 76 bronco.

Is the Roller a better/more efficient motor compared to the Flat Tappet 302! Would it be best to eventually switch the motor from the current 76 302 to the newer 89-92 302?

Or is the difference in mileage not worth it?

 

[broncnaz]

You wont see a mileage differance between two similarly built engines. The Roller is slightly more effiecent due to less friction in the valve train but it makes no differance in mileage.
Overall the roller engine is probably the better choice but there are some small swap issues that will have to addressed.
Unless the roller motor was beat on 100k is not much for those EFI engines they typically go 200K and barely need a rebuild.

 

[mortimersnerd]

Roller motors wear a little better and put out more power. I'm not sure I'd bother rebuilding with only 100k on it. Drop that thing in and go.

 

[Pedestrian]

Agree with above, 100K is nothing for the EFI rollers.

 

[u10072]

EFI roller motors seem to go forever

 

[blubuckaroo]

Another difference is the one piece rear main seal on the roller motor. I can't call it an advantage though since I've had to pull the tranny to replace a leaky one. If you plan to use the FI on the roller, you can expect better driveability and engine life. I can't see better engine life if you use a carb on a roller motor.

 

[broncoitis]

Would it even be worth it to reseal the engine with newer gaskets on the heads, water pump, oil pan, etc.....

I guess that I would need a new cam to bump up the power a bit possibly. Also, will my headers still fit.

I guess what will potential problems be if I make this changeover. All things considered, I think it might be a better option or a big pain in the butt to swap over.

 

[KyleQ]

The headers will fit, the motor is totally fine with that mileage - my 351W with 185K on it needed nothing but a line hone from sitting without cylinder heads on it, still has cross hatching...

 

[Rustytruck]

With the government taking the lead out of the gas and now the zinc out of the oil your better off using the roller motor. Alot of internal and external technology change from 1977 to 1990. You can put 2 grand into your old motor to run 100,000 miles or just slap in the newer motor and run the same distance without putting anything into it or put 2 grand into the newer motor and run 200,000 miles on it. If you want to burn money put the newer motor in and spend your money putting fuel injection back on it.
What ever you do have fun with it.

 

[broncoitis]

The headers will fit, the motor is totally fine with that mileage - my 351W with 185K on it needed nothing but a line hone from sitting without cylinder heads on it, still has cross hatching...

Yeah, I guess that is what I am gonna do. Which is nothing to the motor but swap over my stuff from the current setup eventually and run with it. ;D

With the government taking the lead out of the gas and now the zinc out of the oil your better off using the roller motor. Alot of internal and external technology change from 1977 to 1990. You can put 2 grand into your old motor to run 100,000 miles or just slap in the newer motor and run the same distance without putting anything into it or put 2 grand into the newer motor and run 200,000 miles on it. If you want to burn money put the newer motor in and spend your money putting fuel injection back on it.
What ever you do have fun with it.

I am currently running FI on my rig so that should be a simple change over as well. This just might happen.

What about the flywheel and damper! Can't I just use what I have on the current setup? %)

That would probably be my biggest worry along with swapping over the rockers possibly! My current heads had Studs installed for the rockers and that would be alot more work to have that done at a machine shop.

Hmmm...... a HEART TRANSPLANT just may be in the cards! Would love a Coyote but that would just be too much money at this point in time!

 

[surfer-b]

The only thing I would check is the main and rod bearings, most of those 5.0 mustangs were revved pretty high, kids like to drag them. These are the only parts I have noticed with any wear on them.

 

[bronconut73]

Yeah, I guess that is what I am gonna do. Which is nothing to the motor but swap over my stuff from the current setup eventually and run with it. ;D


I am currently running FI on my rig so that should be a simple change over as well. This just might happen.

What about the flywheel and damper! Can't I just use what I have on the current setup? %)

That would probably be my biggest worry along with swiping over the rockers possibly! My current heads had Studs installed for the rockers and that would be alot more work to have that done at a machine shop.

Hmmm...... a HEART TRANSPLANT just may be in the cards! Would love a Coyote but that would just be too much money at this point in time!

The 5.0 roller motor uses a 50 oz. wt. instead of the 28 oz. wt. your running now. So you will need the harmonic balancer for the 5.0.
A roller motor usually has a wider/flatter torque curve even if it does not make any more peak horsepower. It is part of the reason the old fox body 5.0's felt so quick, they only made about 225 horsepower.

 

[bigmuddy]

I don't see where the engines would produce the same horsepower if both are in stock configurations. A stock 5.0 roller motor is around 225hp while a mid 70's 302 in good shape was between 130 and 150 HP. Not to muddy the waters but the explorer limited 5.0 motors were 275 if memory serves. Seems like a no brainer to me....

I went from a worn out 75 302 in my bronco to a 88-5.0 and it was like night and day.

do it, you will be happy you did.

 

[broncnaz]

explorer motors were only 210-215hp. yes a leap up from the 140 hp 70's motors but on the same note more power needs more gas. mileage doesnt improve. Yes a better choice but up the compression and put a decent cam in a 70's motor asnd your making the same power.
Broncoitis the EFI will swap fine. I'd leave the engine alone and if you went with any cam well it would be a smaller one like the explorer cam. A bigger cam wont really make more power but will move the power up in the RPM's usually not what we want. Want to say that stock 5.0 cam is capible of over 300 hp actually I think you can get close to 400 witha stock cam but Im not 100% on that either way theres no real reason to swap it out. Also wouldnt bother swapping rocker arms or modifing the heads to add them just not worth the money with no gains to be had. but as for the flywheel and balancer well that depends on if have a pre 1982 engine if so then they wont work as the balance is wrong. They can be rebalanced but its probably easier and cheaper to get new stuff.
really you may want to look through the engine swap articles they will give you the ins and outs.

 

[broncoitis]

The 5.0 roller motor uses a 50 oz. wt. instead of the 28 oz. wt. your running now. So you will need the harmonic balancer for the 5.0.
A roller motor usually has a wider/flatter torque curve even if it does not make any more peak horsepower. It is part of the reason the old fox body 5.0's felt so quick, they only made about 225 horsepower.

Ok, so I think I gotta get a balancer possibly! For some reason though I think the old balancer may still be on the motor hopefully! What about the flywheel? Can I use my current flywheel???

I don't see where the engines would produce the same horsepower if both are in stock configurations. A stock 5.0 roller motor is around 225hp while a mid 70's 302 in good shape was between 130 and 150 HP. Not to muddy the waters but the explorer limited 5.0 motors were 275 if memory serves. Seems like a no brainer to me....

I went from a worn out 75 302 in my bronco to a 88-5.0 and it was like night and day.

do it, you will be happy you did.

Yeah, power wise I think that on all fronts it is a no brainer to put the newer engine in the bronco! Should put out alot more power and be more efficient as well.

Were the explorers putting out that much in the HP dept? I'm pretty sure that they were at least at 250 so I guess that 275 is not out of the question.

Would you guys tear the whole thing down and get it cleaned up or just tape it up with duct tape over the cylinders and other areas where water may get in from cleaning and spray it? This is gonna be a winter project for sure! ;D

 

[broncnaz]

210-215 for explorer hp it wasnt until much later with the mod engines that more power was there.
Wouldnt pull anything apart unless it was leaking and needed to be pulled part. just tape and paint. you need a 50 oz flywheel as well.

 

[Rox Crusher]

I did some pretty extensive research when I swapped in a 98 explorer motor which have the GT40P heads.

What I recall is that the P heads gave it a 5 horsepower advantage over the GT40 configured 5.0. It went from 215 to 220 if I recall correctly. I have never heard / seen the 275 figure stated earlier. But maybe this was specific to the Limited version of the explorer, as stated ?

My 5.0 is snappy and responsive off the line.

I would agree that generally these motors easily last 200k if well cared for. Just like anything else, if no maintenance was done then of course the longevity will be affected.

I taped mine up and cleaned it with degreaser and carb cleaner and then painted the heck out of it.

Good luck on your project.

 

[bigmuddy]

explorer motors were only 210-215hp. yes a leap up from the 140 hp 70's motors but on the same note more power needs more gas. mileage doesnt improve. Yes a better choice but up the compression and put a decent cam in a 70's motor asnd your making the same power.

No argument on the gas mileage but why would anyone want to spend the extra money and end up with the same result?

 

[broncnaz]

Jusy sayin theres really no differance even pricewise. build a old one or swap in a junkyard motor. of course building a old one gets you a new one instead of a used one. Most junkyard motors go for around $800 or more then you still have to swap it in so by the time your done you can be into it for way more than a rebuild granted you may get EFI in the process.
I'd also go for a explorer motor if given the choice but it wouldnt go in stock. but thats me

 

[broncoitis]

Jusy sayin theres really no differance even pricewise. build a old one or swap in a junkyard motor. of course building a old one gets you a new one instead of a used one. Most junkyard motors go for around $800 or more then you still have to swap it in so by the time your done you can be into it for way more than a rebuild granted you may get EFI in the process.
I'd also go for a explorer motor if given the choice but it wouldnt go in stock. but thats me

So if you were gonna make any changes to the Mustang motor what would you do? Cam? Rockers? Heads? etc.....

Not lookin to build a beast just a good driver because when it is said and done this truck is gonna see the road and lots of it! ;D

Currently have the explorer upper and lower on current motor which will swap over to the mustang motor! I have 1.7 ratio rockers to swap as well over to the mustang motor! I suppose the timing chain could be swapped as well considering it is new. Explorer P Heads to replace the mustang heads? Cam? Oil Pan needs to be replaced I believe. etc.....%)