this is the cam i got:

Gross Lift

In 431 Ex 431

Advertised Duration

IN 272 EX 272

.050 Duration

In 220 Ex 220

RPM Range

1500---4800

Valve Lash Hot

IN 6 EX 8


i have it in, have the truck running, and the truck is loping extremely hard. i only get it to smooth out by inducing more vacuum (raising idle). And, any small vacuum leak is turnedinto a huge one with this cam iv'e got. So when is big too big? And is this the circumstance? I just can't seem to get my rig running right. thoughts, PPLLLEASE! i want my truck back!!!

That is a fair amount of duration but nothing outrageous. There are a lot of cam specs on Cyber auto's website and Jeff Moskovitz has a few on his website.

What kind of cam is it? Is all of your power up high in the powerband now or can you even drive it in its current condition?

That sounds like the same cam I have, mine works fine but I gave up immediately on the old 750rpm idle. Mine idles smooth above 1000 rpm so that's where I set it. Make sure you don't have any vacuum leaks. Check your TPS to make sure it's adjusted correctly and bump the idle a bit, works for me. It's a little lumpy but it pulls like a mule from 2K to redline.
TPS

Oh yeah you also will want to disconnect your EGR valve. The extra vacuum from the new cam will pull it open prematurely and make your engine run like crap. Just hook it back up at emissions time (if you have that).

sounds like the big Engnbldr cam...i love mine although i dont like the loping at an idle,but i got used to it

Did you time the cam when you installed it? It's also possible that the cam timing is somewhat retarded and this is making things worse. Cam timing is a PITA to check, but it might tell you more about your situation.

This article explains how to degree in a cam on a 22R-series engine.

Jeff

Well, by unplugging the EGR, do you mean simply d/c'ing the vacuum lines, and plugging them up? Or physically removing the assy, and fab up block off plates? Also...no, i didn't time the cam. I just dont understand it. As well as the TPS. I did my best to set it within spec's, but I just dont understand it completely, with those directions 4crawler provides. I guess it doesnt answer the questions i have, mainly. It's a JFE (Johns Foreign Engines, http://22r.biz) RV2 cam.

I'd say your poor idle is caused mostly by your misadjusted TPS. Do this to fix it.
1. Loosen screws that hold it on so you can move it but it's still a little stiff. Disconnect electrical connector.
2. Get little bits of vacuum hose and put them over your meter lead ends so they don't fall off and put them on the bottom two terminals (IDL-E2).
3. Insert a .85mm feeler guage between the throttle stop screw and throttle plate.

4. Check the resistance on the meter. It should be reading OL, or infinite, or open, however your meter displays it.
5. Rotate the TPS until you see the resistance change from OL to something (less than 2.3K ohms). Move the TPS around until that magic point at which it changes is just a tiny bit towards the "something" direction.
6. Tighten the top screw and remove the .85mm feeler and insert the .57 (or something close). You should read some resistance (less than 2.3K ohm).
7. If you don't read anything go back to step 5 and repeat.
8. Tighten the screws and reinstall the connector

Try that and let me know how it works, also to check if it is adjusted right insert the check timing jumper and listen for an audible drop in engine rpm, if you don't get it your TPS is misadjusted.

As far as the EGR I just meant take the single vacuum line going to the EGR valve from the vacuum modulator off and plug it.

>>>*There are a lot of factors to consider when choosing a camshaft.
Often the hard part to understand is that one can make an infinite number of profiles, all with exactly the same lift/duration, and all of them completely different.
*Lobe timing is the key, and how fast the valve opens once it starts to move.
Now some report "lope" even with our design. In nearly every case, I would guess that the head/block have been surfaced. This retards the camshaft timing, and yes, our design will lope and tend to operate in the higher RPM ranges more efficiently if it is retarded by even 2?.
The most common "272/431" design was made by Crane initially, that design is now copied by just about everyone.
We found the .050" lobe timing of 220? to be just a tad too much for the EFI engines, so we reduced it to 219?, (270/430) mostly to improve emissions, and idle quality. We also use the factory 110? lobe centers.
The Crane design is ground on a 108? lobe seperation, and yep! It will lope.
"Lope" begins when airflow velocity is slowed as the area of volume created by the valve action and port exceeds the volume the engine can draw.
This can be improved some by advancing the camshaft by around 2?. There are other tricks, but all of them are much more expensive...*EB

Wow thats alot of cam information. You definately know what you are talking about engblder. Glad i got my stuff from you, came wednesday. <img src="/forums/images/graemlins/cool.gif" alt="" /> I will give a report on my cam once it goes in.