Towing Engine

[mattawajeep]

Thinking about an bigger engine for the Gladiator - this discussion mostly for fun as this will likely happen a couple years into the future. It just needs to get finished in current form first, and since I have paint drying right now I can procrastinate searching for engines for a couple hours.

If I eventually add some sort of in bed camper, or even something similar (though smaller) to Tim's toy hauler, I'm going to want some more power. The 350 will work pulling the TJ for now, I've used 350 powered vehicles to tow and haul some pretty heavy loads, but they don't compare to a big block, especially up hills. The Gladiator likely won't be driven for things other than it's primary purpose - Hauling heavy stuff. So I'm not all that concerned about fuel economy, it probably won't be seeing that many miles.

My original thinking was to grab a re-buildable 454, go over the heads, re-ring the stock pistons (if bores are good), add a new cam and lifters, replace all the bearings, new oil pump, seals, gaskets, intake, carb.

Now, the cost for all the above for parts, fluids, & a couple tools I don't have access to, comes to around $1200 with the original cost of the block factored in. No real clue about machining costs, possibly as much as $500, and then maybe $300 for odds and ends like an AC compressor, brackets, flywheel ect...

79chevy39.5 mentioned that I might be better off starting with a newer engine that's ready to go. I did some quick craigslist searches to see if I could find an 8.1 but nothing showed.

What do you all think?

[Wrench]

The Chevy 6.0 would be my first choice. Tons of aftermarket support, and they are very fuel efficient compared to an older style big-block. They also have huge potential for power increase.

The Chevy 6.0's in the Class C rentals at Broadmoor RV would get 10mpg all day long and pull every hill they ran into. They also pull a Cherokee pretty well...

[mattawajeep]

I'll have to take a look at them.

A 6.0 never crossed my mind as being useful, I always thought they were just a stroked 350 and figured the gas mileage would be about equal with a big block when towing. Our 7000lb tow truck with a 454 gets 11-12 mpg empty if you drive 55. Loaded it tends to get around 9.

I'll have to hunt for numbers, but I'm thinking that the torque can't be anywhere near even a cheaply built 454. Perhaps modern technology compensates somehow.

Other things I'd have to think about are the additional costs of the modern engines. I don't think it will easily bolt up to the rest of my drivetrain like the 454, so I'd probably be sourcing another trans and t-case or getting an adapter of some sort. Not to mention computers, wiring, and all the other sensors. I'd probably have to get another parts truck, or tear everything out of one.

[Wrench]

The 6.0 engine design is SO much more advanced than the old 454. The power is in the cam/heads, intake, and fuel injection system. I have no doubt a well built 6.0 will lay waste to a comparably built 454.

If I remember right, the 6.0 stock numbers are nearly identical to stock 454, but fuel consumption is down. That should tell you something about improved design.

The 6.0 is right around 364ci.

[Grumpy]

366CI...A number I've seen on Chevy truck engines for years. Had 'em in our delivery rigs at Pacific Waterworks in Tacoma. Same design as a 348/409.

[mattawajeep]

The 6.0 engine design is SO much more advanced than the old 454. The power is in the cam/heads, intake, and fuel injection system. I have no doubt a well built 6.0 will lay waste to a comparably built 454.

If I remember right, the 6.0 stock numbers are nearly identical to stock 454, but fuel consumption is down. That should tell you something about improved design.

The 6.0 is right around 383ci.

You're correct. When they're both in stock form the peak numbers are pretty darn close when you compare the higher output 6.0 and the weaker 454's.

I'm going to guess that the torque curves between the two change the story a bit though. There's lots of into out there on the 454, but I haven't found a torque/hp chart for the stock 6.0. The 454 has massive torque off idle, but I'll bet the 6.0 has it's power quite a bit further up the RPM scale, probably well over 4000 rpm.

Still bears looking at though, fuel injection and economy are really nice. Has cool factor going for it (which is a little bit important on a truck like this), though maybe not as much as a big block.

Found this article when searching for mild/cheap 454 builds. They do a really nice job of breaking down the costs, and the torque numbers seem to blow a stock 454 out of the water.

http://www.carcraft.com/techarticles/cc ... lar_build/

Wonder what kind of gas mileage it gets.


ETA: Found a chart for the 6.0, at pirate 4x4 of all places.

http://www.pirate4x4.com/tech/billavist ... ngine.html

It's not as anemic down low as I was expecting, pretty darn good for 366ci but it's still nothing like the 454's numbers.

[79chevy39.5's]

You can bolt your trans up to the 6.0/5.3/8.1....also there's a reason 6.0s are in one tons still today they pull good and with your gearing will scream

[mattawajeep]

You can bolt your trans up to the 6.0/5.3/8.1....also there's a reason 6.0s are in one tons still today they pull good and with your gearing will scream

Yup, looks like it will bolt up. Depending on the block a spacer could be needed for the flywheel, or have a custom flywheel made, there's some funky pilot bearing needed, and you need a block with provisions for bolting up a clutch. Doesn't sound like all of them have it.

Hrm. I'll have to do some looking around.

[79chevy39.5's]

There's lots of info any of them can have sm465 behind it just google lsx with sm465

[SquirrelCrusher]

Swap in a diesel. Towing power, cool factor, and MPG. Get an older 5.9 and no computers to worry about.

[mattawajeep]

There's lots of info any of them can have sm465 behind it just google lsx with sm465

Yeah, I can't find the thread now, but I thought I read something about needing to something funny for clutch linkage stuff - but that's not really a big deal, hydraulic could solve all of that for not much money.

Swap in a diesel. Towing power, cool factor, and MPG. Get an older 5.9 and no computers to worry about.

Heh. An older 6bt would be really easy to drop in and get running, they need like two wires. I think they're going for stupid prices though, maybe I could talk the boss out of our spare.... Probably not.... I'd have to do some research on trans/t-case. No clue what dodge has for that kind of stuff.

Time for bed... I have to actually work on the truck tomorrow, not just yak about it.

[Wrench]

Advantages to the factory 6.0:
-aluminum heads, can handle higher CR than cast iron
-improved combustion chamber design
-dramatically improved intake/port/valve combination
-slimmer valve stems
-behive valve springs (can handle much more aggressive valve events=major power advantages)
-roller tipped rockers
-steel roller cam=more aggressive valve events
-no need for flat-tappet cam oil additives
-free-floating wrist pins in pistons (lower drag)
-ECM, with great tunability

I am sure there are a whole lot more I am not listing. I had an old race-engine builder said that he loves building the newer Vortec engines as they are so much easier to extract power from than the older BBC and SBC setups.

I will say this: I dont know if you were planning on the 454 being carbureted or fuel injected, but a good fuel injection system can DRAMATICALLY increase the life of an engine. Carbureted engines tend to run rich, which tends to wash the oil from the cylinder walls leading to extensive cylinder wear and total engine wear when it reaches the engine oil and saturates it. This is why engines started lasting so much longer after the OBDII system was mandated in 1996 (which integrated monitoring of the quality of fuel injection, forced the use of a closed-loop system, etc).

On another note: I have seen two different (late 90's) Chevy 454's in motorhomes this last year that came down with a valve tick. Both were due to the little plates in the lifter that push the pushrod up getting stuck /cocked sideways inside the lifter. If you dont know, the 454 lifters do not line up directly with the pushrods, they pushrods are angled to the side slightly. The best theory I could come up with is that the hydraulic lifters lost enough oil from sitting for too long that the plate was forced crooked the next time the engine was started. Once cocked sideways, they stick down and leave major slack in the pushrod/rocker, causing a noticable ticking sound. Not cool.

[mattawajeep]

Advantages to the factory 6.0:
-aluminum heads, can handle higher CR than cast iron
-improved combustion chamber design
-dramatically improved intake/port/valve combination
-slimmer valve stems
-behive valve springs (can handle much more aggressive valve events=major power advantages)
-roller tipped rockers
-steel roller cam=more aggressive valve events
-no need for flat-tappet cam oil additives
-free-floating wrist pins in pistons (lower drag)
-ECM, with great tenability

I am sure there are a whole lot more I am not listing. I had an old race-engine builder said that he loves building the newer Vortec engines as they are so much easier to extract power from than the older BBC and SBC setups.

Yeah, the 6.0 is certainly well built, lots of modern goodies packed in there. Pretty much all of that stuff could be added to a 454 rebuild, but it wouldn't be cheap. I'm going to have to look pretty good at costs and see what can get me the most usable power. If I go the 454 route I'll probably stay with a flat tappet cam just because of the cost issues. I can deal with the oil additive thing, I have 3 vehicles right now, and every single one has a flat tappet cam. Bought a bunch of additive in bulk cheap, so I'm set for a good long while.

About it being easier to squeeze out more power.... Seems to me like it might be harder, as the only reason it's making so much to start with is all the added goodies. Perhaps your guy was talking about it being a bit cheaper to squeeze out the last remaining HP because so much has been paid for already.

I will say this: I dont know if you were planning on the 454 being carbureted or fuel injected, but a good fuel injection system can DRAMATICALLY increase the life of an engine. Carbureted engines tend to run rich, which tends to wash the oil from the cylinder walls leading to extensive cylinder wear and total engine wear when it reaches the engine oil and saturates it. This is why engines started lasting so much longer after the OBDII system was mandated in 1996 (which integrated monitoring of the quality of fuel injection, forced the use of a closed-loop system, etc).

Yeah, can't really argue against fuel injection, especially if it's something cheap like TBI. Whatever I end up doing it'll be tuned. If I go carb, I'll be getting a multi-band O2 sensor, and tuning the heck out of the carb. That doesn't help as much on startup, but it'll go a long way to adding more life.

I've got to think about how much life I'm actually going to realistically need out of an engine as well. Even if the engine were to blow up at 100,000 miles that's a whole heck of a lot of trips to the mountains. This won't be a daily driver. I've got my mustang for that, and after I swap in a 5-speed I'm hoping for 18-20 mpg.

On another note: I have seen two different (late 90's) Chevy 454's in motorhomes this last year that came down with a valve tick. Both were due to the little plates in the lifter that push the pushrod up getting stuck /cocked sideways inside the lifter. If you dont know, the 454 lifters do not line up directly with the pushrods, they pushrods are angled to the side slightly. The best theory I could come up with is that the hydraulic lifters lost enough oil from sitting for too long that the plate was forced crooked the next time the engine was started. Once cocked sideways, they stick down and leave major slack in the pushrod/rocker, causing a noticable ticking sound. Not cool.

Huh, I wonder if the angle is dependent on what heads you're running.

If I go that route I'll certainly have to pay attention to lifter selection and oiling. I was already looking at potential issues from flat tappet lifters. There's a lot of talk out there of modifying the lifter oil valley and groove to get more flow through the lifter and to then splash it onto the cam in advance of the contact patch.

I'll have to do some price comparisons tonight and figure out some cost/power ratios for various builds. Might even look at costs for a cheap stoker build. Wonder how cheaply a 496 can be built, and what kind of power number can be had with a moderate build.

[White trash]

For what you're doing at this point I'd just leave the small block. Snag a nice low to midrange cam and double roller timing chain and go with it.



Later on down the road I'd look into either a 6bt or even a DT466 diesel if you really want to have a tow rig with power. Gassers are nice but when it comes to moving weight there is a reason you don't see unleaded being used in the heavy industries.



If you want to go efi I've got a complete tbi setup I'd let go rather cheaply.

[79chevy39.5's]

The reason I didn't suggest cummins or other diesel was trans..... figured cost was too high

[White trash]

The reason I didn't suggest cummins or other diesel was trans..... figured cost was too high

6bt+NP435+NP205=cheap nearly bolt in.

[79chevy39.5's]

What about the cost of going insane because 14 is top speed....the 727 3.08 geared truckswweren't fun to drive

[Grumpy]

If you want to go efi I've got a complete tbi setup I'd let go rather cheaply. Very Happy

2bbl I 'spose?

[White trash]

What about the cost of going insane because 14 is top speed....the 727 3.08 geared truckswweren't fun to drive

Old slushboxes sucked behind 6bt's. A 435 wouldn't be too bad with say 3.73's and 33's. Granted I'd never subject an old j truck chassis to the mildest of 6bt's since the torque and vibration would destroy it.




Yes grumpy it's a 2 barrel from an 89 suburban. I should have each and every piece for it other than the fuel tank.

[mattawajeep]

Of course the diesel would probably be the best bet for an industrial rig. I'm not sure it's worth the expense for something that'll at the very most see 2500 miles per year.

I've never driven a 6bt truck with an automatic, but I doubt that it makes much difference. Our two farm trucks with 6bt's pull heavy loads great, but they're not all that fun to drive.

Gas gives you the ability to do a bit of both. Id be afraid that a 6bt built to the point of being fun would turn my truck frame into a pretzel. And like trash mentions, they vibrate like crazy. I had to go to some silly lengths to get the murphy panels on our modified irrigation 6bt's to keep from falling apart.

The 6bt's 1100 lbs might balance out the 42 gallon tank I have planned for the rear though.


You guys with the TBI's for sale, are those for a big block or the 350?

[SquirrelCrusher]

4BT?

My dad's 5.9 with an auto is stock and is pretty fun to drive. Just add a few more crossmembers.

[White trash]

You guys with the TBI's for sale, are those for a big block or the 350?

350

[mattawajeep]

You guys with the TBI's for sale, are those for a big block or the 350?

350

Any thoughts on TBI along with a bigger cam? I've heard they don't play well together. If they don't mix opinions on what will gain the most power and economy? I've already got a 4 barrel intake and carb.

[White trash]

You're right tbi doesn't play well with a huge cam but keeping the cam in the sane range that a tow rig demands would be fine.

[Grumpy]

Phooey, mine's a 4bbl intake...