Well the specs he gave me on the heads matched what i found for stock, down to the casting number. So not i'm lost. He called a couple guys he knows and got some ideas. He's coming over to the house tonight to test his theories. He is still leaning towards open valves. Wish us luck, we're gonna need it.

 

Well, we ran test after test and came to the same conclusion. He said i needed to get EXACT specs on the cam. Called MABBCO today, they couldnt give me EXACT specs but told me he's pretty sure on the .480 cams that the intake and exhaust duration is .286/,286. From what i have seen that's pretty high and should be around .200/.206. Thoughts??

 

And just called the cam guy again, he seems to be "99% sure" its the programming in the truck.

 

Then have him explain the low comp numbers. lol

 

By relaxing the rockers for your tests you have taken the cam, timing, pushrods, out of the eq.

There should have been a cam card included with the cam where is it? It has all the specs on it. If you don't have it then the engine builder might have it.

Is this a regrind for a cam? new?

 

When pigs fly.

 

thats exactly what i said

 

not a clue where it is. It was new cam. I called them to get specs, .480 lift, 286/286 advertised duration..... their "cam guy" was about useless. Only thing that helped was telling me the advertised duration. So i called richard at Hi-potek. Damn he was a huge help. Seems that the 286 advertised duration equates to about 230/236 duration...which he said is too much cam and not enough motor. Which is why when i ordered the damn thing i specifically told them i wanted a MILD CAM. apparently they didn't get that. Looks like i'm either going to a) pull this cam out and see if i can get it re-ground nearby to the specs richard gave me, or b) pull it out, see if any of you guys on here have the motor for it, and get a cam that richard advised me on. Pretty pissed that they didnt give me the mild cam i asked for. But also gotta take part of the blame since i didn't give them EXACT specs. I just assumed they knew what the hell mild meant. At least we're about 99% sure it's the cam. So guess what i'll be doing this weekend!?

 

Advertised duration, and duration at .050" lift, are two entirely different numbers.

Given that you have zero leakdown, even at 100 PSI, the problem MUST be cam timing. Intake valves are either opening to late, or closing too soon.

 

well about to order Hi-poteks 212XR cam. Anyone need a stock cam to re-grind or a .480 cam with a 230 duration!? At least i know WTF it is now!