I'm tryin to decide on a cam for my 86 f250 mud truck. I want something that has a noticeable idle and tremendous horsepower/torque in the 3500-4500 rmp range. The truck isn't a daily driver and is only a woods truck. The engine is a low compression 79-80 460 out of an econoline van (I think). Should I use a 218/218, 216/228, 226/230, or a 230/230. I was also planning on using rhoads lifters for better low end torque. I'll change over to an adjustable roller rocker setup to get rid of the factory nonsense. Anybody run a similiar cam have any feedback? Thanks guys

 

What all are you doing to the motor? you said it was low compression so im guessing youre leaving it at that. anything else? i ran those cams into my new desktop dyno 2000 (woohoo!) and left everything constant (including lift...which will probably be higher with the higher duration.) for a pretty much stock motor, the 218 had the most horsepower and torque at 3500 but was then passed up by the 216/228 between 4-4500. the two bigger cams both had less torque from 35-45 than the 216/28, and surprisingly, less horsepower to boot. im guessing that without more done to it (namely heads and compression) the motor isnt going to be making much use of the bigger cams, especially at those rpms. get back to me with more info and i can give you some #'s and a better idea of what cam will work best based on the rest of the combo. by the way, i have a 218/218 in my mild 429 and it feels about right for what im running. with my weight, 33" tires, stock converter, and 3.54 gears, its about as big as i would want to go. it pulls fairly hard off the line but needs improvement. after some more engine work and lower gears, i think ill be ready for a bigger cam though. the setup i have right now is great for offroading though. it has so much torque at idle in 4lo that i really have to mash the brakes to keep it still, and barely tapping the gas snaps your head back. =) but at the same time, it has a lot of mid range and top end for when i need to make a hard run on a mud bog. anyways, its pretty hard to screw up on a big block, so i think youll be happy whichever way you go on the cam. good luck

 

>I'm tryin to decide on a cam for my 86 f250 mud truck. I
>want something that has a noticeable idle and tremendous
>horsepower/torque in the 3500-4500 rmp range. The truck
>isn't a daily driver and is only a woods truck. The engine
>is a low compression 79-80 460 out of an econoline van (I
>think). Should I use a 218/218, 216/228, 226/230, or a
>230/230. I was also planning on using rhoads lifters for
>better low end torque. I'll change over to an adjustable
>roller rocker setup to get rid of the factory nonsense.
>Anybody run a similiar cam have any feedback? Thanks guys

If you want a HP peak to be in that range, that aint gonna give a noticable lope at idle. A grunt cam like that sould idle pretty smooth. You called it a mud truck, if so you want a cam targeting 6500 or so, no? Or are you talking mud in your back yard/woods and not a mud racer? The mud racers run big numbers in RPM, HP, and would never do a low compression smog head 460....so I guess you mean that you want to play in the woods. In that case, read my post on valve size, listen to that truck I give you a link to, and I'll sale you the cam and lifters for 50.00, or you can go buy similar new on your own for 120.00. That cam is most likely what your looking for with your set up. You can't get good flow for big lift and such, so go for a low-mid monster. That 460 dyno-ed out nicely for a mild build.You should see about 340 HP with some porting and a bit of planing on the heads. If your chasing a "Noticable Idle" you got to give up on the low side. It comes with big duration, and that usually comes with bigger lift. The big duration promots reversion and it takes rpm's to get past the reversion effect. Most biger duration cams are just waking up at 3000-3500 rpm. I would forgo the large idle lope, and get what will let you torque throught he mud, rocks, and hill climbs.

 

If you want a rumpy idle, you can also just pick something with a tighter LSA to increase overlap. This also actually boosts midrange power, and raises your dynamic compression. Something with 218* duration will be fine in the 3500-4500rpm range, but not much more. Problem is, as mentioned, it will be very mild. Have one custom ground on a 108LSA and it will help with HP, and with a meaner idle.

 

Well right now the engine has the D3VE A2A heads but I'm looking for a set of earlier heads to boost compression. I figure it should make a bunch more power with the earlier heads, plus I'd be able to run a longer duration cam. The truck has 3.54 gears, 36 inch swampers, and a 4 speed granny transmission.

 

I would recomment the CompCams 268H . It has a mild lope at an idle and makes gobs of power from 1500-5500rpm. I run one in my 77 Lincoln low compression 460 that is in my 77 F150. I changed the cam, lifters, Valve springs and added a double roller timing chain( old chain was only 2 years old, but stock chains have a 4 degree timing retard built in). It makes alot more power now. I already had headers, 2 1/4 duals w/Flowmasters, An Edelbrock Performer intake and 750 Carb.