# Whats the difference between 4.0. and 4.0 H.O **URL:** \ **Category:** General Discussion\ **Tags:** cherokee, jeep\ **Created:** [December 23, 2010, 9:59pm UTC](https://community.cartalk.com/t/whats-the-difference-between-4-0-and-4-0-h-o/59109 "2010-12-23T21:59:40Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![\_Deleted\_User1111116](https://avatars.discourse-cdn.com/v4/letter/_/ac91a4/32.png) [@\_Deleted\_User1111116](https://community.cartalk.com/u/_Deleted_User1111116)\ **Post date:** [December 23, 2010, 9:59pm UTC](https://community.cartalk.com/t/whats-the-difference-between-4-0-and-4-0-h-o/59109/1 "2010-12-23T21:59:40Z")
Jeep has 4.0 and 4.0 H.O. What are the mechanical differences. Horse power? ---
**Author:** ![\_Deleted\_User1111116](https://avatars.discourse-cdn.com/v4/letter/_/ac91a4/32.png) [@\_Deleted\_User1111116](https://community.cartalk.com/u/_Deleted_User1111116)\ **Post date:** [December 23, 2010, 10:02pm UTC](https://community.cartalk.com/t/whats-the-difference-between-4-0-and-4-0-h-o/59109/2 "2010-12-23T22:02:14Z")
I guess i could google horse power… ---
**Author:** ![Rod-Knox](https://avatars.discourse-cdn.com/v4/letter/r/a183cd/32.png) [@Rod-Knox](https://community.cartalk.com/u/Rod-Knox)\ **Post date:** [December 23, 2010, 10:37pm UTC](https://community.cartalk.com/t/whats-the-difference-between-4-0-and-4-0-h-o/59109/3 "2010-12-23T22:37:02Z")
Sounds like a plan to me. ---
**Author:** ![\_Deleted\_User1111116](https://avatars.discourse-cdn.com/v4/letter/_/ac91a4/32.png) [@\_Deleted\_User1111116](https://community.cartalk.com/u/_Deleted_User1111116)\ **Post date:** [December 23, 2010, 11:14pm UTC](https://community.cartalk.com/t/whats-the-difference-between-4-0-and-4-0-h-o/59109/4 "2010-12-23T23:14:30Z")
190 ---
**Author:** ![\_Deleted\_User1111116](https://avatars.discourse-cdn.com/v4/letter/_/ac91a4/32.png) [@\_Deleted\_User1111116](https://community.cartalk.com/u/_Deleted_User1111116)\ **Post date:** [December 23, 2010, 11:16pm UTC](https://community.cartalk.com/t/whats-the-difference-between-4-0-and-4-0-h-o/59109/5 "2010-12-23T23:16:42Z")
What makes an H.O. an H.O. is it that blower sticking out of the hood ---
**Author:** ![jtsanders](https://avatars.discourse-cdn.com/v4/letter/j/c2a13f/32.png) [@jtsanders](https://community.cartalk.com/u/jtsanders)\ **Post date:** [December 23, 2010, 11:25pm UTC](https://community.cartalk.com/t/whats-the-difference-between-4-0-and-4-0-h-o/59109/6 "2010-12-23T23:25:01Z")
A slight redesign in 1991 led to an increase in horsepower. ---
**Author:** ![VDCdriver](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/vdcdriver/32/48514_2.png) [@VDCdriver](https://community.cartalk.com/u/VDCdriver)\ **Post date:** [December 23, 2010, 11:29pm UTC](https://community.cartalk.com/t/whats-the-difference-between-4-0-and-4-0-h-o/59109/7 "2010-12-23T23:29:16Z")
A “blower” sticking out of the hood? “Blower” usually refers to a supercharger, and I have never seen a factory-stock Jeep equipped with a supercharger. Perhaps you are talking about a hood scoop, but a hood scoop is not necessarily an indication of anything other than a styling affectation. Cars with a turbocharger or a supercharger will usually have a hood scoop, but I could probably come up with a fairly extensive list of vehicles without a forced induction system that also have a hood scoop–such as some Jeeps. ---
**Author:** ![\_Deleted\_User1111116](https://avatars.discourse-cdn.com/v4/letter/_/ac91a4/32.png) [@\_Deleted\_User1111116](https://community.cartalk.com/u/_Deleted_User1111116)\ **Post date:** [December 23, 2010, 11:35pm UTC](https://community.cartalk.com/t/whats-the-difference-between-4-0-and-4-0-h-o/59109/8 "2010-12-23T23:35:58Z")
I was just screwing around…to much time on my hands ---
**Author:** ![\_Deleted\_User1111116](https://avatars.discourse-cdn.com/v4/letter/_/ac91a4/32.png) [@\_Deleted\_User1111116](https://community.cartalk.com/u/_Deleted_User1111116)\ **Post date:** [December 23, 2010, 11:37pm UTC](https://community.cartalk.com/t/whats-the-difference-between-4-0-and-4-0-h-o/59109/9 "2010-12-23T23:37:19Z")
I understand that but whats different about the high output That is whats mechanically different ---
**Author:** ![VDCdriver](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/vdcdriver/32/48514_2.png) [@VDCdriver](https://community.cartalk.com/u/VDCdriver)\ **Post date:** [December 23, 2010, 11:40pm UTC](https://community.cartalk.com/t/whats-the-difference-between-4-0-and-4-0-h-o/59109/10 "2010-12-23T23:40:10Z")
The H.O. engine had–IIRC–larger valves, larger intake passages, and improved injectors. Possibly, it also had a higher-compression cylinder head. ---
**Author:** ![\_Deleted\_User1111116](https://avatars.discourse-cdn.com/v4/letter/_/ac91a4/32.png) [@\_Deleted\_User1111116](https://community.cartalk.com/u/_Deleted_User1111116)\ **Post date:** [December 23, 2010, 11:42pm UTC](https://community.cartalk.com/t/whats-the-difference-between-4-0-and-4-0-h-o/59109/11 "2010-12-23T23:42:39Z")
That helps…Thanks