Driving the 6 speed manual
03-07-2009, 06:24 PM
#51
JK Super Freak
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Well, the engine has zero low end, thats why you need to rev it to get power. However, it does not "like" to be revved. Its a horribly balanced engine with no counter balance shafts (like just about every modern V6 has, even those dating back to the late 80's). Which is why it gets loud as the RPM go up, and why it never idles as smooth as more modern engines.
I wish my Jeep had a 4.0 in it. The low end grunt of an i6 cannot be matched by a V6. I could care less about top end HP, I want low to mid range torque.
I wish my Jeep had a 4.0 in it. The low end grunt of an i6 cannot be matched by a V6. I could care less about top end HP, I want low to mid range torque.
03-07-2009, 06:30 PM
#52
JK Junkie
Personally I prefer an engine that has tons of low end, and goes to mid range rpm when driving a truck or Jeep. High end HP is useless to me where I am. I do no mud and no sand. Just crawling. When crawling, low end torque is everything.
03-07-2009, 06:30 PM
#53
JK Junkie
What he means is its a very poorly balanced engine. It will build power at upper RPM yes. But it does not run smoothly up there.
03-07-2009, 06:35 PM
#55
JK Super Freak
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That dyno sheet was originally shown in a JP Magazine review of the JK (where their biggest complain was the engine). It came directly from Chrysler, and is not a real dyno sheet, its a target that they were shooting for. The V6 in my JK will not pull well below 1000rpm. It bucks and sputters and eventually dies. With every 258/4.0 I have driven, they pull smoothly down to 400rpm. Which is NICE off road.
Something a dyno doesn't show is rotational mass. The V6 in the JK is *WAY* easier to stall than an inline 6. Not to mention an inline 6 is naturally harmonically balanced (the only engine that runs smoother is a V12). Plus, when you have 7 main bearings, and only 1 piston per journal, it makes for a very strong engine. The 4.0 (and the 258/232 that it was based on) has proven itself for the past 35 years as being an extremely reliable engine, known for having a lot of low end grunt. I have almost 250k miles on the 258 in my other Jeep, and it still runs extremely well.
I would gladly give up a few more HP at an RPM that I never use to pick up grunt at the RPM that I use the most.
Something a dyno doesn't show is rotational mass. The V6 in the JK is *WAY* easier to stall than an inline 6. Not to mention an inline 6 is naturally harmonically balanced (the only engine that runs smoother is a V12). Plus, when you have 7 main bearings, and only 1 piston per journal, it makes for a very strong engine. The 4.0 (and the 258/232 that it was based on) has proven itself for the past 35 years as being an extremely reliable engine, known for having a lot of low end grunt. I have almost 250k miles on the 258 in my other Jeep, and it still runs extremely well.
I would gladly give up a few more HP at an RPM that I never use to pick up grunt at the RPM that I use the most.
V6's do not idle anywhere near 400K and the electronics are not programmed for it. Stall speed also has to due with your gearing. Try stalling it in 4Lo.
Inline anythings are more difficult to balance, a 7 cylinder inline is very much smoother than a 6.
Wnat more torque? then get some decent gears.
03-07-2009, 06:39 PM
#56
JK Freak
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Well, the engine has zero low end, thats why you need to rev it to get power. However, it does not "like" to be revved. Its a horribly balanced engine with no counter balance shafts (like just about every modern V6 has, even those dating back to the late 80's). Which is why it gets loud as the RPM go up, and why it never idles as smooth as more modern engines.
I wish my Jeep had a 4.0 in it. The low end grunt of an i6 cannot be matched by a V6. I could care less about top end HP, I want low to mid range torque.
I wish my Jeep had a 4.0 in it. The low end grunt of an i6 cannot be matched by a V6. I could care less about top end HP, I want low to mid range torque.
03-07-2009, 06:48 PM
#57
JK Super Freak
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I think some of you guys are blaming a lot of stuff on the engine when it is your gearing and tire sizes. Don't believe me? Try a real test drive with something like a Rubi or any Jeep that has 4:10 gears/six speed. I think you'll change your minds unless that sucker has been driven/broken in slowly. We all have after all, DBW Jeeps
03-08-2009, 09:37 AM
#58
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Last edited by 999666; 03-08-2009 at 12:24 PM.
03-09-2009, 07:45 PM
#59
JK Super Freak
I think some of you guys are blaming a lot of stuff on the engine when it is your gearing and tire sizes. Don't believe me? Try a real test drive with something like a Rubi or any Jeep that has 4:10 gears/six speed. I think you'll change your minds unless that sucker has been driven/broken in slowly. We all have after all, DBW Jeeps