02 GC 4.7
Thread Starter
CF Veteran
Joined: Jun 2010
Posts: 1,220
Likes: 5
From: Arkansas
Year: 1987 & 1996
Model: Cherokee
Engine: 4.0
02 GC 4.7
Curious thing.
Got this of GC from a friend that picked it up as an abandoned vehicle.
Runs great.
Air box says 4.7 HIGH OUTPUT
But looking on the heads the HO is missing.
So curious if someone replaced the Heads, or the Air Box. or WTF is going on there.
what other difference is there on the outside of the engine I can use to ID this engine?
Got this of GC from a friend that picked it up as an abandoned vehicle.
Runs great.
Air box says 4.7 HIGH OUTPUT
But looking on the heads the HO is missing.
So curious if someone replaced the Heads, or the Air Box. or WTF is going on there.
what other difference is there on the outside of the engine I can use to ID this engine?
Old fart with a wrench
Joined: Nov 2010
Posts: 14,398
Likes: 741
From: Manlius, east of Syracuse, NY
Year: 2000 XJ Sport & WJ Laredo
Model: Grand Cherokee (WJ)
Engine: 4.0L
The 4.7 HO started with the 2002 models and the differences are about 30 more hp and 9.7 compression instead of 9.0. One other way you can tell is the spark plugs. The intakes are SPRC7PYCB4 and the exhaust are RC7PYCB4. They use a platinum rivet for an electrode and should never be cleaned or the gap adjusted.
For maximum performance, it requires 93 octane fuel, although it runs fine on 87.
All this info can be found on wjjeeps.com
For maximum performance, it requires 93 octane fuel, although it runs fine on 87.
All this info can be found on wjjeeps.com
Thread Starter
CF Veteran
Joined: Jun 2010
Posts: 1,220
Likes: 5
From: Arkansas
Year: 1987 & 1996
Model: Cherokee
Engine: 4.0
The 4.7 HO started with the 2002 models and the differences are about 30 more hp and 9.7 compression instead of 9.0. One other way you can tell is the spark plugs. The intakes are SPRC7PYCB4 and the exhaust are RC7PYCB4. They use a platinum rivet for an electrode and should never be cleaned or the gap adjusted.
For maximum performance, it requires 93 octane fuel, although it runs fine on 87.
All this info can be found on wjjeeps.com
For maximum performance, it requires 93 octane fuel, although it runs fine on 87.
All this info can be found on wjjeeps.com
Doesn't state is all HO's have the HO on the head.
Some say yes, some say no.
Thanks XJ 4.3 for your iinfo too.
just looked up VIN and it came with an H.O.
its unmolested as you can see.
So going to assume that not all HO's had the head casting.
Maybe sometime later I'll get a chance to pull intake and see if there is dual knock sensors in the valley.
just for giggles here she is.
Rouhg around the edges but for a nearly free WJ not complaining.
