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Texops

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Thanks - I love it.
I have a 401 I have had for 4 or 5 years sitting on a stand in my shop all covered up (along with a 343 and most of another 360) - need to rebuild it and have it ready for this car. I have Scorpion rollers for it and other odds and ends.
Also have a spare TF727 I plan on building so one of these days, I'll actually do it and swap that into the car. Nice thing is that the 401 will drop in and use the same headers and - well, you know - nothing changes. Same externals.
That 401 is the best ever engine, i tried to buy a 76 Gladiator with a built factory 401 had 450 hp but he kept backing out of the deal.
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ShadowsPapa

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I remember my 1st brand new vehicle a 1983 Jeep CJ-7 Renegade in Copper head. It had a 258cid straight six cylinder (4.2) for those young folk. 112 HP . But it weighed 3200# 5 speed and good torque down low. Had it 12 years a daily driver never wanted more power.
Yup - those engines lasted and lasted. I know guys with over 200,000 on them. Good torque. The 258 in my SX4 finally started losing oil pressure at 160,000 miles so I decided to have a bit of fun and put a 4.0 in it. Same bolt pattern, engine mounts and such. It also has the T5 five speed.
I've had 4 vehicles with the 258 - 2 of them Eagles if I don't count the one I sold and one waiting for a new body.

Those remind me of the first Jeeps I worked on.
 

Texops

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Yup - those engines lasted and lasted. I know guys with over 200,000 on them. Good torque. The 258 in my SX4 finally started losing oil pressure at 160,000 miles so I decided to have a bit of fun and put a 4.0 in it. Same bolt pattern, engine mounts and such. It also has the T5 five speed.
I've had 4 vehicles with the 258 - 2 of them Eagles if I don't count the one I sold and one waiting for a new body.

Those remind me of the first Jeeps I worked on.
Very Jeep like vehicle, my dad had a new 1975 AMC hornet wagon silver/black very cool ride 258 with an auto.
 

hjdca

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Yup - those engines lasted and lasted. I know guys with over 200,000 on them. Good torque. The 258 in my SX4 finally started losing oil pressure at 160,000 miles so I decided to have a bit of fun and put a 4.0 in it. Same bolt pattern, engine mounts and such. It also has the T5 five speed.
I've had 4 vehicles with the 258 - 2 of them Eagles if I don't count the one I sold and one waiting for a new body.

Those remind me of the first Jeeps I worked on.
There is something about the straight six that equals longevity. Every straight six I have been part of has lasted tons and tons of miles, over 200K miles ie. old Jeep straight six, old Land Cruiser straight six, old Buick straight six, and even BMW straight six ------ then there is the old Mercedes Diesel straight six that you used to hear of going 800K miles and more being used as taxi cabs in Europe....

I remember reading somewhere that the architecture and balance of the straight six is the reason for this longevity. Too bad they are too long to put in modern cars....
 

Rocksalt

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Not necessarily. Look at Ford's F-150. The EcoBoost V6 gets the same MPG as the Coyote V8 in the real world, and LESS MPG while towing/hauling than the V8. Larger displacement engines don't have to work as hard to produce the same output. So, they don't need as much fuel.



Yeah, 1998 ZJ 5.9 Limited.. World's Fastest SUV and WITH a solid front axle. But that was a totally different time from a crash test standpoint and gasoline was $0.89/gallon here in Kentucky when that Jeep came out. Today's Grand Cherokee SRT8 is still fast, but it doesn't have to meet the demands of rock crawling and it has different cooling needs. Plus the engine bay is larger.



Why? A full size truck adds weight. A V8 in a midsize would be the most fun and most useful I think.



Heck, the 3.6L Pentastar out performs the V8 from the Dakota if you're talking speed. I think everybody today wants more torque in their Jeeps though, and that's where a V8 would come into play. You could have a lot more torque without the expensive and finicky nature of the diesel.
I get it, you would like more torque and HP. I am simply saying that I am happy with the 3.6. I agree with you about a v8 vs a diesel..
 

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MarineHawk

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There is something about the straight six that equals longevity. Every straight six I have been part of has lasted tons and tons of miles, over 200K miles ie. old Jeep straight six, old Land Cruiser straight six, old Buick straight six, and even BMW straight six ------ then there is the old Mercedes Diesel straight six that you used to hear of going 800K miles and more being used as taxi cabs in Europe....

I remember reading somewhere that the architecture and balance of the straight six is the reason for this longevity. Too bad they are too long to put in modern cars....
The H3 had an inline 5-cylinder engine. The one I recently had to hand over to my separated wife has run 102K miles without the slightest hiccup. Not so much for the transmission and a few other things.
 

ShadowsPapa

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I wonder if there's room.......................

Jeep Gladiator Factory V8 allison
 

jalbrecht55

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I’ve had/have both the 258 and the 4.0 I6. Honestly I’m not a fan at all. Both have been slow, noisy, underpowered gas hogs for me. Only good thing I can say is that they do have good low end grunt. My 4.0 will chug over things at idle in high range that would stall out my Toyota 4cyl with dual transfercases... funny story my wife drove my LJ and panicked pulling into a parking spot, forgetting to push in the clutch. (She’s learning).

Pushing the brake as hard as she could it drove over the curb, through the bushes over the hill through the ditch and back up out onto the adjacent road. :)

For some reason after that she said she’s done with learning to drive a manual.

I said I’m just glad she didn’t take the space facing the building.
 

ShadowsPapa

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I’ve had/have both the 258 and the 4.0 I6. Honestly I’m not a fan at all. Both have been slow, noisy, underpowered gas hogs for me. Only good thing I can say is that they do have good low end grunt. My 4.0 will chug over things at idle in high range that would stall out my Toyota 4cyl with dual transfercases... funny story my wife drove my LJ and panicked pulling into a parking spot, forgetting to push in the clutch. (She’s learning).

Pushing the brake as hard as she could it drove over the curb, through the bushes over the hill through the ditch and back up out onto the adjacent road. :)

For some reason after that she said she’s done with learning to drive a manual.

I said I’m just glad she didn’t take the space facing the building.
The 4.0 I put in my Eagle will get me anywhere from 18 mpg to 27 mpg, depending on driving. Fast in that car is not good for MPG but if I keep it under 65 or so, it does great. It really does very well in mixed driving and in town. It's a T5 behind it and the axle ratio is high- that's how those cars were equipped. High enough I never hit 5th unless I'm doing at least 50 or 55. It will go up a 4 degree grade at 40 mph and accelerate without struggle in 4th gear (which is high or 1:1 in the T5.
The other Eagle I bought new in 84 with 258 did great on gas as well and it made fantastic time when my first wife went into labor with our second son - and when it started we knew there was no time to lose. She reclined the passenger seat, I hit I35 north to Mason City and pretty much pegged the speedometer most of the way there - without trouble doing so. We got there and she was rushed to a room, Jason pretty much popped out 5 minutes after they got her into the room. We credit that Eagle wagon with getting her there in time.
I raced a Javelin with the AMC 6 back in the 70s and beat a few small block 8s. Did autocross with it as well.
Another car I had with a 258 I drove to Denver and around the mountains for a week or so, then back to Iowa again - good mileage and great power up in the mountains, around Pike's Peak and so on - no lack of power, didn't have to gas up often.
The 258 is a pretty quiet engine normally. The 4.0 sounds more like a truck engine - but, oh, wait - it was - and was developed for the Jeep. Mine is a bit more noisy because I put a Comp xtreme 4x4 cam in it and those xtreme cams have some more radical ramps and slam the valves open and drop them closed (so you don't need as much lift to get the same air in and out)
want roller rockers with them............

I've built a few of those 232, 258 and 4.0 engines over the years.

Jeep Gladiator Factory V8 eagle-jeep-rockers-002
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ShadowsPapa

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Thanks Bill, forgot about the stroke part.
Cheers
Trust me, I forget things I knew years ago - sometimes I think I've forgotten more than I ever knew!
I learn stuff - or am reminded of things, pretty much every day.
The day comes when I don't learn something - time for the pine box.
I pity those who go even a single day and don't learn something. It's what makes life fun, IMO. And life is a blast!
 

Rocksalt

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Trust me, I forget things I knew years ago - sometimes I think I've forgotten more than I ever knew!
I learn stuff - or am reminded of things, pretty much every day.
The day comes when I don't learn something - time for the pine box.
I pity those who go even a single day and don't learn something. It's what makes life fun, IMO. And life is a blast!
Amen!
 

Factoid

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I dropped a 6.2L LS motor and 6L80 tranny from a 2012 Camaro in my 1988 LR Defender 90 a few years ago. From 85hp to 480hp in a few weeks. It was awesome! Sold it on BaT last year and have missed it ever since. I’m itchy for a V8.

Here’s my middle daughter helping me demo it.



Jeep Gladiator Factory V8 9AFAF5F6-22F6-4D3C-9448-5B790BCC6D5E
 

Rocksalt

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I dropped a 6.2L LS motor and 6L80 tranny from a 2012 Camaro in my 1988 LR Defender 90 a few years ago. From 85hp to 480hp in a few weeks. It was awesome! Sold it on BaT last year and have missed it ever since. I’m itchy for a V8.

Here’s my middle daughter helping me demo it.



9AFAF5F6-22F6-4D3C-9448-5B790BCC6D5E.jpeg
good luck with the JT
 

Mr._Bill

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Damn, Nissan Leafs are faster than I thought! :LOL:
They do fly. I can beat most cars off the line, and be at speed before they get through the intersection. It hurts range to drive that way, but they are fast little cars.
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