Inliners International Forums General Discussion AMC/JEEP Right Cam?

I would like some expert opinions. I am upgrading my '69 Javelin as follows: '73 258 short block (stock), my existing 232 head with 1.95" intake - 1.50" exhaust valves, 904 Torque Command w/ 1800 stall converter, "20" rear end with 352:1 gears, a possible upgrade from my 390 cfm Holley to a 500cfm Edelbrock, and a new cam. The cam is the issue. I already bought a "Comp Cams - Extreme Energy" cam and kit (not yet installed) with the following specs: .493" - .512" lift (intake & exhaust), and 218 & 226 degrees dur. @.050" (intake & exhaust). This cam has a 111 degree lobe seperation. I bought this cam because Comp advertises that due to an aggresive lobe ramp causing a more rapid timing event, these cams produce better vaccuum and low end and mid-range power than other cams of similar specs. However, I've since talked to a techy at Clifford performance who says that a cam for this application needs to be a single pattern cam of less lift and duration than what I have. While I'd very much like to use what I've already got, I don't wan't to make a mistake either. My goal for this car will be mostly street driven, with occassional trips to the strip where I'd like to have the potential of at least 14 second ET's. Someone like to weigh in on this?

Sorry folks,
I had a brain fart when I gave the intake valve size. I meant to type 1.65".

Javelindan

I think the cam will work ok for the way you want to use the car,know a guy using one in a 258 powered Gremlin and he is happy with it.
Not trying to spend your money but you might want
to look into installing the 4.0 H.O. cyl. head.
Word is its worth 25 to 40 h.p. over the standard 258 head. There are quite a few showing
up in salvage yards and not real expensive. As
of 6 months ago they could be had for 150.00 or
less. The heads were used on '91 up Jeep Cherokees. Casting number 7120.

Gordy

Hi, Dan, here's my 2 cent's worth, and I'll start off by saying that I'm not an AMC person, having never owned one, but I have been playing with inline sixes for a few years. Back in the middle 70's, I built a 194 chevy six, and used a Sig Erson cam in it with .480" lift and 256 degrees advertised duration (they didn't use the .050" standard then) on both intake and exhaust, plus Clifford intake, Holley 350 cfm 2-bbl, and Clifford headers and glass packs. The cam was listed as an RV cam by Erson. It idled very smoothly, and pulled like a John Deere from idle to 5000 rpm. Wouldn't rev higher than that, but I didn't really care. It sounds like your cam is a little hotter than the one I used, but not a lot, about 10 or 12 degrees more duration and a bit more lift. It should still be pretty streetable and give you decent gas mileage, and GOBS

of torque in the midrange. Sorry about cutting off the last message........hit the wrong key. And depending on the exhaust system you're running, should have pretty decent top end, too. Good luck with it, and have fun.

Javelindan,

I'd expect I have more experience than anyone else on this planet when it comes to hopping up a 258 in a 69 Javelin, as I've run that combo on the street/strip for about 20 years, with times in the 13'9's.

The cam I use currently is a Crane, with 218/224 @ 0.050, and .494/.512 lift, on 112 degree lobe center. I love it. It idles very well, and with quiet mufflers on it you couldn't tell it isn't stock. With a pair of 2.5" Dynomax mufflers you can hear it lope a bit. It pulls really smooth, and pulls hard up to the 6200 rpm I shift at. If I could improve the cam, I'd add faster ramp rates (the AMC uses a large lifter and can afford a faster ramp than a Chevy) and I'd tighten the lobe center to 111. SOUND FAMILIAR? IT'S THE CAM YOU HAVE!

That cam will give you great street/strip results, easy 14's, and low 13's if you really go after them with the other mods. Keep the compression down to 10:1 or lower - I've run 11.25:1 and the cam just builds too much pressure at low RPM, making it very hard to crank over and start when hot.

Clifford's folks don't know the AMC the way they know other inlines, and who can blame them as almost nobody drag races with one.

I'd skip the large valve conversion - it's really not going to help you (I run stock valve sizes in a 1968 era 199 head). The 4.0L head offers much more.

Chris in KC