CK5
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GM 4.2 straight 6
- Thread starter HankScorpio
- Start date
Finnegan just did a turbo one into the death metal charger.
It would blow the OC-12 rear right out of a snowcat but it would sound incredible doing it.
It would blow the OC-12 rear right out of a snowcat but it would sound incredible doing it.
We had one of these for the power company in moab. It was trimmed down to 10k due to license restrictions for the guy that towed it and used it most. They have a similar one here local to me now that is a crew cab and has a big enclosed box on the back. I've never had it in the snow but it will do 25 mph across a parking lot no problem. They are fun and I've heard they will straight up or down whatever you want depending on snow conditions.
Prinoth trooper is a sweet machine. Not a ton of groomers end up as personal cats, just too wide to fit down the trails.
The little one in moab was narrower for weight savings but the one my buddy has at the power company here has the extended width tracks.
Those little ones like you have are definitely more nimble and easier to take anywhere.
I had the 4.2L I6 in my trailblazer I drove for ~7 years as my daily, had 160K on it and it ran like new, didn't burn any oil. I changed the plugs once at about 80K and the air filters, etc and ran it like that until I sold it. It was a good engine, didn't get very good mileage in that application, averaged ~17, but it worked good, I really liked that vehicle. The DOHC with VVT helped it run pretty good, and it even had an aluminum block so it was likely pretty light. It also held a lot of oil for a stock 6 cylinder, I think 7 or 8 quarts if I remember correctly.
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I guess I hadn't thought about an aluminum block, even better. The large oil capacity is great. The jeep straight 6 were the same, I think its part of the reason they lasted so long, lots of oil.
Vortec 4200: GM's Powerful DOHC Inline Six Was Almost America's 2JZ
Was the Chevy Trailblazer and GMC Envoy engine the greatest American inline six ever?
www.drivingline.com
The Forgotten Inline Engine: GM’s 4.2-liter Atlas I-6
The real story of GM’s high-tech straight-six, its impact on GM's engines, and why it was discontinued
www.topspeed.com
Didn't the axle shaft pass through a hole in the oil pan on 4x4 Trailblazers?
And why did GM abandon the I6 at the end of the Trailblazer run for the LS?
And why did GM abandon the I6 at the end of the Trailblazer run for the LS?
Even the 2wd 4.2 has the hole for the axle to pass through.
I’m guessing the 4.2 had run it’s course. Gm had been moving away from body on frame suvs to more fwd crossover style units. So a big in-line six wasn’t fitting the plan. The 3.6 that came in the Traverse that replaced the trailblazer made 300 hp and still had better fuel economy.
The above articles touch on it, the 6 was great but didn't fit in the transverse mounting of the new SUV platforms. Having 2 completely different mounting patterns stopped it from being a base engine for the trucks or even the camaro. Much easier to use a V8 and V6 as the 2 engine options fitment wise.
The 4.2 looks to be an excellent engine and its all aluminum which is a bonus. With no distributor and drive by wire, doing anything non stock looks to be difficult. The guys building boosted ones are running megasquirt. The engine controls will probably be the deciding factor for me in this application. I have not found stand alone harnesses or much ECU programing information yet. Like many others there is anti theft, torque management and such programed in. EFI live may be able to deal with all those things but its all new to me.
The 4.2 looks to be an excellent engine and its all aluminum which is a bonus. With no distributor and drive by wire, doing anything non stock looks to be difficult. The guys building boosted ones are running megasquirt. The engine controls will probably be the deciding factor for me in this application. I have not found stand alone harnesses or much ECU programing information yet. Like many others there is anti theft, torque management and such programed in. EFI live may be able to deal with all those things but its all new to me.
Power Nation has build videos on a Chevy 292 straight 6 and also a boosted 300 Ford.
I would bet the Holley can control it, Terminator X Max or HP/Dominator. It's just a matter of the correct connectors and setup. I can help you set it up if needed with the software and wiring harness to purchase, etc.
The closest thing is probably to start with a LS DBW harness, and remove two of the coil and injector plugs, etc. I know it can run the DBW but not sure on which connectors are the same, etc.
We'd also need to know how many teeth on the crank and cam targets, etc. I've read some are 58x, not sure what the others are on the 4200?
The closest thing is probably to start with a LS DBW harness, and remove two of the coil and injector plugs, etc. I know it can run the DBW but not sure on which connectors are the same, etc.
We'd also need to know how many teeth on the crank and cam targets, etc. I've read some are 58x, not sure what the others are on the 4200?
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I like the idea of the aluminum engine for snow, lighter is better. Good power and fuel injection would be great too. Going to be a slow project, need to find a 4200 first. Took some measurements and it might be possible to fit a V8 with some fab work on the tunnel. Not sure if I want to go that route, weight is important but V8 has all the info and engine controls are easy. Bellhousing has more options too. Electronic trans worries me but I know that there are standalone controllers and the terminator has capabilities too. I can't throw unlimited power to this thing, the OC12 rear end is only strong enough, it's a pretty old Oliver tractor designed unit used in the 60's and 70's in snow cats. A big 6.0 or aluminum 6.2 would be a waste so the 4200 would be a great motor. 4200 also makes great torque all the way across the RPM range.
Yeah I saw it had 90% of full torque from about 1500-5000 or something. It has a lot of stroke compared to the bore size, the I6 is a good engine really. I'd take that over a 90 degree V6 to be honest. A 60 degree V6 makes more sense balance wise but most are small and don't make the torque.
I would think weight would definitely be a factor. The Holley can control the trans too. And the difference in cost between controlling just DBW, or DBW and trans is only about $225 at this time.
Does an OD trans make any sense in that thing though, could you use the OD gear?
I would think weight would definitely be a factor. The Holley can control the trans too. And the difference in cost between controlling just DBW, or DBW and trans is only about $225 at this time.
Does an OD trans make any sense in that thing though, could you use the OD gear?
OD does make sense as long as there is enough power. They are really slow but there is no reason that they can't run 30mph+ if the trail is smooth. All the bogies are on independent torsion axles so they can absorb bumps like a tank.
Going to have to check on that. Ring and pinion, times a drop box that moves the axle centerline lower. Then couple that with the fact that the drive cogs on the track are small. Like putting little car tires on a truck.
