3.0 Strength (pistons, bottom end, block etc)

[icytower387]

i've been doing some mild research on the strength of a 3.0 vulcan since im very close to getting my hands on a dirt cheep 91 ranger that has one in it, a cool goal would be to put a 4r70w and do a "mild" build on the vulcan to make it capable of towing as much as a f series, put some air bags in the rear, maybe brace the frame etc etc...

but from what i can find, all that is said about the 3.0 is that "it's not that good" and "it'll be really expensive"

but what about the specifics? how much hp/torque can the block handle? the bottom end? pistons rods crank? sure it might be weak but what parts of it exactly

if you tell me it has like...... 2 bolt main caps and the bolts are super tiny then i'd understand there's no saving it but i need more specifics, i at least know the head needs alot of work to flow the necessary amount of air for anything to be attempted.

and since i'd be aiming for more of a torque build, if the block and everything else is kind of weak then... oh well lol.

 

[franklin2]

Do some research and see if you can buy anything to build it with. Usually engines that are not popular to build, do not have any aftermarket support. I have never research building a 3.0, but have ran across this with other engines. The path of least resistance is sometimes the way to go. (as in a more popular engine to build).

 

[RonD]

Welcome to TRS

The 3.0l Vulcan was designed as a high RPM engine, so best used with a manual transmission where DRIVER controls the shift points
Most engines make best torque at 2,700rpms
3.0l Vulcan does that at 3,700rpms, so you need to keep the RPMs high for best power

This is why they got the nickname "3.slow" as most have automatics with shift points well under best torque RPMs for this engine

3.0l Vulcan also runs 9.3:1 compression ratio so not a great candidate for Boost, but you can boost it
Under 5psi boost should be safe


The 4R or 5R44E automatics are rated for 440ft/lb torque so are fine for towing alot of weight, the problem is the LEGAL aspect
(Manual transmission can only take about 300ft/lb, which is why they have a much lower tow rating, just FYI)

The VIN on the vehicle sets the legal limit for towing capacity or overall weight, GCWR
You can put in a V8, 4R70W and a 9" rear axle, and the LEGAL limit still applies

Any Ranger can tow more than it's legal limit, but if there is an accident(not even weight related) your insurance company can leave you hanging, because of the "operate vehicle in a LEGAL and lawful manner"

Towing or bed weight limits are also related to Brakes, and just like the engine/trans changes it doesn't matter if you use bigger brakes, doesn't change a thing for the legal limits

If you want to tow at F-150 capacity then get an F-150

 

[franklin2]

Welcome to TRS

The 3.0l Vulcan was designed as a high RPM engine, so best used with a manual transmission where DRIVER controls the shift points
Most engines make best torque at 2,700rpms
3.0l Vulcan does that at 3,700rpms, so you need to keep the RPMs high for best power

Definitely not a good towing engine candidate. Another reason why a automatic is rated higher for towing on most all vehicles is it has another "virtual gear" the manual doesn't have that comes from the converter slip.

 

[icytower387]

Welcome to TRS

The 3.0l Vulcan was designed as a high RPM engine, so best used with a manual transmission where DRIVER controls the shift points
Most engines make best torque at 2,700rpms
3.0l Vulcan does that at 3,700rpms, so you need to keep the RPMs high for best power

This is why they got the nickname "3.slow" as most have automatics with shift points well under best torque RPMs for this engine

3.0l Vulcan also runs 9.3:1 compression ratio so not a great candidate for Boost, but you can boost it
Under 5psi boost should be safe


The 4R or 5R44E automatics are rated for 440ft/lb torque so are fine for towing alot of weight, the problem is the LEGAL aspect
(Manual transmission can only take about 300ft/lb, which is why they have a much lower tow rating, just FYI)

The VIN on the vehicle sets the legal limit for towing capacity or overall weight, GCWR
You can put in a V8, 4R70W and a 9" rear axle, and the LEGAL limit still applies

Any Ranger can tow more than it's legal limit, but if there is an accident(not even weight related) your insurance company can leave you hanging, because of the "operate vehicle in a LEGAL and lawful manner"

Towing or bed weight limits are also related to Brakes, and just like the engine/trans changes it doesn't matter if you use bigger brakes, doesn't change a thing for the legal limits

If you want to tow at F-150 capacity then get an F-150

i see, oh well, maybe i'll do some very mild mods to it to give it a little help but other than that it just sounds like 5.0 is the way to go
i would ask about economy but, im sure a 5.0 decently built with a computer/tuner/whatever with multiple tunes can probably manage good fuel economy if not better than the 3.0 from what i've read around anyway

 

[stmitch]

i've been doing some mild research on the strength of a 3.0 vulcan since im very close to getting my hands on a dirt cheep 91 ranger that has one in it, a cool goal would be to put a 4r70w and do a "mild" build on the vulcan to make it capable of towing as much as a f series, put some air bags in the rear, maybe brace the frame etc etc...

but from what i can find, all that is said about the 3.0 is that "it's not that good" and "it'll be really expensive"

but what about the specifics? how much hp/torque can the block handle? the bottom end? pistons rods crank? sure it might be weak but what parts of it exactly

if you tell me it has like...... 2 bolt main caps and the bolts are super tiny then i'd understand there's no saving it but i need more specifics, i at least know the head needs alot of work to flow the necessary amount of air for anything to be attempted.

and since i'd be aiming for more of a torque build, if the block and everything else is kind of weak then... oh well lol.

Blocks got added strengthening ribs over the years, so later is generally better. There haven't been many people push the absolute limits of the 3.0, so I can't say that the block is good for XXXhp or anything. There was a member here (JP02XLT I think) that ran a whipple supercharger on his 3.0. He stretched a rod bolt running like 18 psi and spinning it around 7k rpm. There are now ARP upgrades available for the rod bolts I'm pretty sure. Other than that, I'm not sure that anybody has broken one due to pushing the limits too much.
The whipple supercharger kits that were developed with (and warrantied by) Ford Racing ran ~10psi with nothing but a software tune so I'm pretty confident that that amount of boost is safe for a good long as long as the tune is good.
I run 10psi with a pretty worked over 3.0 on e85. Balanced bottom end, ARP head studs, lots of porting, roller rockers, etc. I didn't build it to tow, but it's a good time for an engine that many people look down upon.

That being said, I'm not sure that a one-of highly stressed 6 cyl is the way to go for what you want. A 5.0 could probably get you the same or better power for less money.