Cam=Rough Idle?

[Rednek]

I only have one question...

Does the cam cause a rough idle... not dieing but just rough?

 

[Mike G]

If its a good one it will give it a lope at idle. Nothing better then a good cam firing through cold headers.

 

[Rednek]

lope?

 

[walnuts75]

Lope makes the tuck sound like vroommm!!!VROOMMM!!!vroomm!!VROOOMMMM!!! Sorry I dont know how else to descibe it. It sounds like the engine is overlapping. Since you screen name is Redneck, I assume that you have been to a few tractor/truck pulls in your life. Loping can be easily heard from a lot of the pulling trucks. They idle a bit differently.

 

[bidibronco]

Theres a lot of thing to be concidered about a cam. Yes, a large cam will give a noticable idle. The "lope" he's talking about it the way the cam makes the engine sound. Getting a cam for the sole purpuse of the lope isn't a good idea. There is a such thing as "overcam" and it's when the cam is to big for the application and actually robs HP.

 

[Rednek]

walnut

i live for tractor pulls man.. heh and its not redneck.. its rednek like team rednek...

keepin it country thats all.

cuz i already got a cam and i got a f#@!ing tight ass "lope" omg ppl are so jealous!!!!!!!!!!

lol

all who are helping me "bidi,walnut,mike" check out this video

watch the whole video liek when he it just idling in the driveway

is that "lope"????

 

[BLADE262US]

One thing you guys have to remember this truck has speed denstity efi which means that the EEC is preprogrammed with the cam specs if you get outside of them you will loose power to the point of possibly not being drivable . You cant fool the computer on the cam . You would have to have it reprogrammed /emoticons/[email protected] 2x" width="20" height="20" />

 

[bidibronco]

Or you can get a cam that is speced to work with the computer. That's what I did but I'll admit that it idles a little funny. I'm at work so I can't check out the video, sorry.... The "lope" you hear usually comes from the lobe sep. The smaller the number the bigger the "lope." I can't think of the "correct" way to describe it?

 

[Leadsled]

The "lope" in the video is not from the cam but from a massive amount of boost being made by the charger at idle. Actual "lope" from a cam occurs when the cam is ground with a long duration. Both valves are actually open at the same time for a very very short period of time. Anything bigger than an rv cam will have a "lope".

 

[bidibronco]

Is it the duration of the lift or is it the lobe sep? I thought it was the lobe sep because that would give you the overlap wouldn't it?

 

[crazyhorse85]

I always thought it was depended on duration of the lift of the cam that gave you the lope....

 

[BLADE262US]

I agree with crazyhorse on this one /emoticons/[email protected] 2x" width="20" height="20" />

 

[Crude dude]

Look up Van Halen - Hot for teacher. The beginning drum solo is a perfect description for a lopey cam....haha I dont feel tardy

 

[American Thunder]

watch the whole video liek when he it just idling in the drivewayis that "lope"????

My Mustang has a "lope" you could say.(Idling at 1400 rpm) Solid lifter camshaft, 260 duration @.050" and .605" lift.

http://videos.streetfire.net/video/BURNOUT...ng-II_11661.htm

 

[BLADE262US]

Your mustang is also mass air if I remember right and his truck is speed density too completely different animals . /emoticons/[email protected] 2x" width="20" height="20" />

 

[American Thunder]

Your mustang is also mass air if I remember right and his truck is speed density too completely different animals . /emoticons/[email protected] 2x" width="20" height="20" />

My mustang has a Barry Grant 750 Race Demon carb on the stroker motor. I don't do fuel injection. I was merely demonstrating what a loping idle from an aggressive cam sounds like.

The speed density problem you mentioned mostly just effects idle quality. Once it's revving, they usually perform OK. That system will handle slight modifications to the engine, and even a mild camshaft, but once you pass a certain point, the computer becomes a spaz. Loping from a large camshaft sounds a lot different than when the engine is surging up and down from a speed density system operating outside its parameters, though.

The fix is to either convert to carb or convert to mass air flow.

 

[Mike G]

Ford Bronco lope.

 

[bidibronco]

My mustang has a Barry Grant 750 Race Demon carb on the stroker motor. I don't do fuel injection. I was merely demonstrating what a loping idle from an aggressive cam sounds like.The speed density problem you mentioned mostly just effects idle quality. Once it's revving, they usually perform OK. That system will handle slight modifications to the engine, and even a mild camshaft, but once you pass a certain point, the computer becomes a spaz. Loping from a large camshaft sounds a lot different than when the engine is surging up and down from a speed density system operating outside its parameters, though.

The fix is to either convert to carb or convert to mass air flow.

Agreed 100%. Even though I have a mild cam with 1.7 roller rockers I have a funny idle but as soon as the engine hits anything over about 1200 rpms (less than anything I see at any given speed) it smooths out like butter. The idle isn't bad but noticable. Nothing that sounds like a lope to me. Just a little bit of the speed density acting up. Runs like a scalded dog and has good low end for me. Speed density is a gremlin for cams though.