Building a 10,000 RPM Jeep 4.0

Brianj5600

Brianj5600

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Very interesting for gearheads. I kept on seeing in my Youtube suggestions, but didn't watch it because the picture appeared to be clickbait. It is a multi video series of Jeep engine development and I am half way through volume 2 and hooked. I want one of those cylinder heads.

 
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Zorba said:
That was EXACTLY my thought as well. What good does 10K RPM do you in an application where you really need/want low end grunt?
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Maybe if you are rock crawling, but not everyone is. High RPMs and HP can be advantageous in some applications like sand or mud. Or for the 99.9% of the time most Wranglers spend on paved roads.
 
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Zorba said:
That was EXACTLY my thought as well. What good does 10K RPM do you in an application where you really need/want low end grunt?
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I neither need nor want low end grunt. The transfer case gearing and axle gears can handle all of that quite well. What I need is something with enough mid range grunt to stay up with traffic on other than flat ground, enough RPM to drop a gear or two and run at higher RPM to get up hills when needed, and a tolerable amount of grunt at other than the low end to cruise at 70-75 MPH in OD at 25-2600 rpm and not downshift when it encounters a 1% grade.

Something like the Atlas 4.2 would be perfect.
 
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mrblaine said:
I neither need nor want low end grunt. The transfer case gearing and axle gears can handle all of that quite well. What I need is something with enough mid range grunt to stay up with traffic on other than flat ground, enough RPM to drop a gear or two and run at higher RPM to get up hills when needed, and a tolerable amount of grunt at other than the low end to cruise at 70-75 MPH in OD at 25-2600 rpm and not downshift when it encounters a 1% grade.

Something like the Atlas 4.2 would be perfect.
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I want GOBS of torque right off of idle (read: Diesel) - but that's me. Its what I grew up with, its what I find driveable, its what I like. High revs do nothing for me. Yes, good drivetrain gearing helps immensely (and good luck finding THAT today), but lack of low end annoys me - you don't have to gear down as much/often if the engine has the low end power to accomplish the job in the first place.

My employer had a Ranger pickup - had to rev the damn thing over 3K to even BEGIN to get anything out of it - and yea, you had to not just shift outta OD, you had to go down 2 gears to make it over an overpass! Not my idea of fun - completely gutless even compared to an early 70s Mercedes Diesel!
 
Jerry Bransford said:
Why? Wouldn't that be about like mounting a scramjet engine onto the Wright Flyer?
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True , but hasn't this been done for over 60 years with jeeps ?
Think of it this way , back in the day folks swapped in a 327 SBC into a flatty that had a 60 h.p. 4 banger. The 300 h.p. 327 has 5 times the horsepower.
Fast forward to today , If I did the equivalent to my 99 242 I would have to replace it with an engine with 905 h.p.

Truly there is nothing new under the sun. :)
 
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Zorba said:
I want GOBS of torque right off of idle (read: Diesel) - but that's me. Its what I grew up with, its what I find driveable, its what I like. High revs do nothing for me. Yes, good drivetrain gearing helps immensely (and good luck finding THAT today), but lack of low end annoys me - you don't have to gear down as much/often if the engine has the low end power to accomplish the job in the first place.

My employer had a Ranger pickup - had to rev the damn thing over 3K to even BEGIN to get anything out of it - and yea, you had to not just shift outta OD, you had to go down 2 gears to make it over an overpass! Not my idea of fun - completely gutless even compared to an early 70s Mercedes Diesel!
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Meh, whatever.
 
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Brianj5600 said:
Very interesting for gearheads. I kept on seeing in my Youtube suggestions, but didn't watch it because the picture appeared to be clickbait. It is a multi video series of Jeep engine development and I am half way through volume 2 and hooked. I want one of those cylinder heads.
Click to expand...
Listen to a couple of these now, these are interesting/entertaining. Good fodder for some bench racing discussion!
 
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Brianj5600 said:
Very interesting for gearheads. I kept on seeing in my Youtube suggestions, but didn't watch it because the picture appeared to be clickbait. It is a multi video series of Jeep engine development and I am half way through volume 2 and hooked. I want one of those cylinder heads.

Click to expand...

Interesting history. The first episode should be required listening for young people. It shows how you should train in your area if interest bc you’ll naturally excell out of sheer interest and background study that others aren’t doing. As an educator I see it every day. It’s clear who the driven students are.
 
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Jezza said:
It can go too far. My S2000 had no guts under 6k RPM. Above that it would scream. That made dead stop starts a pain.
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I remember driving a new S2000 20 years ago when I was looking for a new car. I liked it, but not as much as I thought I would. Great fun when you were really working it hard but gutless in normal driving. Still, it was a looker and handled well.
 
Woodrow said:
I remember driving a new S2000 20 years ago when I was looking for a new car. I liked it, but not as much as I thought I would. Great fun when you were really working it hard but gutless in normal driving. Still, it was a looker and handled well.
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The S2000 torque was better in 04 and up cars. That made daily driving less of a chore.
 
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mrblaine said:
I neither need nor want low end grunt. The transfer case gearing and axle gears can handle all of that quite well. What I need is something with enough mid range grunt to stay up with traffic on other than flat ground, enough RPM to drop a gear or two and run at higher RPM to get up hills when needed, and a tolerable amount of grunt at other than the low end to cruise at 70-75 MPH in OD at 25-2600 rpm and not downshift when it encounters a 1% grade.

Something like the Atlas 4.2 would be perfect.
Click to expand...

Something like the 4.2 engine is what the TJ should have really come with. 4.0 was already well past it's prime even during the YJ timeframe.
 
Zorba said:
I want GOBS of torque right off of idle (read: Diesel) - but that's me. Its what I grew up with, its what I find driveable, its what I like. High revs do nothing for me. Yes, good drivetrain gearing helps immensely (and good luck finding THAT today), but lack of low end annoys me - you don't have to gear down as much/often if the engine has the low end power to accomplish the job in the first place.

My employer had a Ranger pickup - had to rev the damn thing over 3K to even BEGIN to get anything out of it - and yea, you had to not just shift outta OD, you had to go down 2 gears to make it over an overpass! Not my idea of fun - completely gutless even compared to an early 70s Mercedes Diesel!
Click to expand...

Offroading, torque isn't why we gear down, it's to get a wheel speed that agrees with a vehicle speed desired for controllability and grip (aka really effing slow). If you're geared for that to begin with, the torque takes care of itself.

I want more power every time I hit the interstate. I've never been in 4 low and wanted for torque.
 
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freedom_in_4low said:
I want more power every time I hit the interstate. I've never been in 4 low and wanted for torque.
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Even in JV, we've run with lots of folks who are not geared correctly, still run the 231 but the auto trans torque converter takes care of the rest. Where neither of those work very well is at highway speed. God forbid you want to run up to Big Bear with stock gears and 35's.
 
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