cmartin2112

Hey guys so I know I posted about this earlier but I really need some insite before I do this.

I want to order a new cam for 89 4.0. The reason being is I am rebuilding my motor and my current cam is worn out and there is a few lobes that have chips in them... So I am wondering should I stay OEM or upgrade? I have heard that the OEM cams are designed to provide a high amount of torque compared to other OEM cams. But its not that much of a price diffrence ($40 to $50) to go with the comp cams set through summit (CL68-232-4). If I upgrade I am assuming I need to get new valve springs... Would I have to replace the rockers and the push rods? I just had a valve job done on my head so would I have to replace my valves too?

SeriousOffroad

If you're goint ot replace the cam you should also replace the lifters and push rods.

An aftermarket cam won't make a huge difference in the output of your motor.

VTJeep

Yea, but air-fuel-spark? (and compression) What other components are aftermarket on his jeep to provide increased delivery of afore mentioned 3 things? Free flowing air, more fuel and hotter spark are all well and good, but without increasing any of that, an aftermarket can isnt worth it. Just my two Lincoln's...

SeriousOffroad

That's why I stated that an aftermarket cam won't make a huge difference. It's only 1 piece of the puzzle.

VTJeep

Word.. I was skimming so I guess I missed that little bit at the end, haha..

cmartin2112

I am going to put spectre cowl intake, aftermarket exhaust, as far as ignition I tried to look for upgrades but there are'nt to many out there. I will porbably be getting my head port and polished with the valve job also will be replacing/upgrading fuel injectors too. The block was bored over .04 with new pistons, rings, bearings, serviced crank, and all the other things that go along with the full rebuild.

cmartin2112

Oh yeah I alos forgot to mention that the aftermarket cam is a kit and it comes with new lifters.

SeriousOffroad

The big problem here is the motor itself. Renix motors have lower horsepower and torque output than their HO brethren.

I don't see adding parts to a low HP/Tq motor as making much sense. The Return on Investment just isn't there, and there's very little aftermarket support for the Renix era motors.

cmartin2112

Dang... So I guess I will probably just go with OEM cam since it makes more since. Then spend $200 and not see any changes... Thanks for the advice SeriousOffroad.

cmartin2112

So I actually ordered a melling cam from O'riely's today... It was way cheaper and since melling a pretty well known name I figured that was the best choice.