Before I order my new cam, I'd like a little confirmation that 4.0 and 4.2 cams are swapable. Summit Racing has a Comp Cams 252h pn 68-200-4 listed, but it only comes up when searching AMC 258. If you search a Jeep 4.0, Summit wants to sell you the cam that seems most popular on here but it has more than .480" lift, and would most likely require valve springs.
The reason I'm more interested in the 252h is because it's a big improvement over stock, but still only has .433" valve lift, which I assume would work just fine with stock 4.0 springs in a 4000 max rpm motor without any valve float or over compressing the springs.
Cam Compatibility?
-
Rescue Diver
- Posts: 6
- Joined: July 2nd, 2012, 6:02 am
- Stroker Displacement: 4.7
- Vehicle Year: 1979
- Vehicle Make: Jeep
- Vehicle Model: CJ-7
-
Rescue Diver
- Posts: 6
- Joined: July 2nd, 2012, 6:02 am
- Stroker Displacement: 4.7
- Vehicle Year: 1979
- Vehicle Make: Jeep
- Vehicle Model: CJ-7
Re: Cam Compatibility?
I got the answer from Summit. Their site said the 68-200-4 252h grind fits through 87, but their book shows it'll also fit a 4.0 through 97, so the cams are interchangeable between 258's and 4.0's.
I have a 252h on order, and with only .433 valve lift, I see no reason why it won't work just fine with stock 4.0 springs.
I have a 252h on order, and with only .433 valve lift, I see no reason why it won't work just fine with stock 4.0 springs.
Who is online
Users browsing this forum: No registered users and 2 guests