Cams
 

Well I decided not to do a 4v swap instead I'm going to build up my 2v 5.4 (mainly cause of the cost of a 4v swap) I pretty much found everything I need but I don't know much about cams, I was thinking about a comp cam 102530. Does anyone know much about this cam? Or know of a better cam? I was looking for more of torque since this motor will be in a lifted 4x4.

Well, i cant find info on what the specs for the stock cam are, but from the looks of it, that looks like a pretty mild cam at .475 lift. i dont think you'd even have to change the valve springs (not saying to re-use the old springs, you'd still need to replace them, but you wouldnt need aftermarket springs i dont think) Best thing to do man is call comp cams themselves, and they can either custom spec you a cam, or tell you what cam suits your needs! Its been awhile since i did a bunch of reading on cams, but either more duration or more lift will give you more torque, which is what youre wanting. dont quote me on that, but IIRC, that holds some water. Let us know what comp says man! id like a set for my truck!

i guess ill call them sometime, it will be hard catching them since i work a 13 hour day. I also finally got around to building my motor on desktop dyno today, and it shows with the 102530 cam it will make 476tq @2000 and 335hp @5000 at the fly wheel with the cam advanced 5 degrees. I also put in the comp 102500 cam wich has more lift and it lost a few ftlbs but gained some hp. I guess ill play around with some different cams on there, but i dont want to base my discision on what desktop dyno says.

Man this is why I love this forum! THe diversity of waht you can learn is endless! :thumbup:

X2

Never believe exactly what a desktop dyno says. Those numbers are only accurate with in 20%. I built a 310CI Ford and on a actual engine dyno the engine made 60+Hp and 45tq over what the desktop dyno said. It can also be lower.

Longer duration means more torque because the valves stay open longer at low rpm. Where more lift Creates higher horsepower opening the valves more but in less time, making them able to open/close faster at high rpm.

I've run numerous sets of cams in modular engines. I think a custom grind set would be better. I never liked the ramp rates of Comps Cams for modulars. You will need better than stock springs for any of them.

I knew it was one of them, but i had one of those "brain farts" :thumbsup:


Why must you change them? Excuse my ignorance, i come from the Chevy LS pushrod world, and .475 is smaller than a stock cam! Does it have to do with the fact that its an OHC motor? I wasnt sure if the valvetrain geometry had something to do with it. (you know, like when you change the rocker arm ratio?)

OP also, dont forget that if youre going to run an auto tranny you are also going to lose around 20% of your crank HP due to drivetrain.

Also Car crazy, do you recall what kind of lobes you used on these modular motors?