gblauf

iTrader: (1)

I have an 08 Chev 5.3 silverado 4x4. I recently put a Comp Thumpr Cam in it and am having a few problems. First, my truck has port match heads, headers, flow super 44, intake, 4.56 gears, 2500 stall converter, 1.8 roller rockers, Predator tuner and the Comp Thumpr 219/233 cam. Cam provides lots of power and i love it but it came at a price. I was getting DTC codes p1175 and p1174 which are cam sensor codes so i took everything back apart and moved the cam gear 1 tooth. Now the Cam codes are gone but i get p0016, which is CKP sensor or timing off!! I give up. Can anyone help me. I am about to put the stock cam back in!

I used the 3 bolt cam gear (4x sensors) out of an 06 vette to make this cam work since my factory one was a single bolt.

Any help woulld be great.

Thanks gb

00ChevyScott

iTrader: (10)

Take it back apart, make sure the dots are aligned properly (it's really not that hard to do) and get a real tune. Also, what springs, lifters, and pushrods are you using?

gblauf

iTrader: (1)

Dumb question, but what dot am i lookng for on the crank gear? i only saw a yellow paint dot from the factory that i have been using as my referance. Are there engraved timing marks i should be looking for?

Other than my rockers everything else is stock.

gb

sonoma43

iTrader: (1)

Well, to start with you need some new pushrods (hardened) and some new valve springs. Neither of those stock will hold up to that cam. There are timing marks on the cam gear and the crank gear, they need to be dot to dot.

00Silv4.8

iTrader: (10)

^^^ yes those timing marks are engraved

budhayes3

iTrader: (19)

Your cam sensor is on the front of the motor correct? Does the Vette cam gear have the necessary tab on it for the sensor?

chevrolade

iTrader: (22)

i ran this cam before,with no problems.i used the 3 bolt the ls7 sprocket...may wanna check your dot to dot alignment...and yes get a real tune...i got mine from nelson performance in san antonio.theres vids on mine on youtube.

Pontiac Derek

iTrader: (6)

Ok, First Off, You need to degree your cam, Every Cam Ive ever seen and degreed my self has been off from 2-8 degrees, Thats a Mile in Engine building talk, I really Notice in the LS/Gen 3 scene this step is skipped and have heard many say you don't need to do it LOL, Thats Ludacris! You Must Degree any Cam you install, And you will need an Adjustable Timing set like the LS2 Adjustable set i got from Yank, First If you put your cam gear dot at the 6 o'clock position and crank gear in the 12 o'clock position #6 cylinder will be firing which is ok as its easier to line up that way, but when you degree your cam you need to be on #1 and since the cam spins half as fast as the crankshaft all you do is rotate the engine 1 revolution now both the cam gear and crank gear dots will be in the 12 o'clock positions and thats #1 Firing, This is easiest with the Driver side head off, Get a Dial indicator and stand and mount it to the deck with the dial indicator in the very center of the piston, now install a Degree wheel either to a Pro series LS Crankshaft Socket or if possible to your damper now rotate the engine and with your eyes watch and see the Piston reach TDC or at least close, now take a coat hanger and bend into an "L" and find a location to bolt it to the front of the engine "this will be your timing pointer" and rotate the degree wheel till its at TDC on the Degree wheel and snug down the degree wheel but make sure you can still adjust it so not too tight, Now back the engine up .050 inches on the Dial Indicator and check where the degree wheel/pointer is at say 15 degrees remember that now rotate the engine clockwise to 0 then another .050 and check the Degree wheel if it says 15 degrees your at TDC, Your just Making Sure 100% where exact TDC is at otherwise your cam will be off, Ok now that we have TDC located and the Degree wheel is locked sollid so it can't move were going to take the dial indicator and put it on the #1 Intake Push rod "Second Push rod going front to back on Driver Side" or Lifter just make sure if its hydraulic you put the indcator on the edge where its sollid, K now rotate the engine till you find the Max Lift of the cam lobe Lets say .350 remember that now back up "counter Clockwise" past .300 to say .250 or whatever then going clockwise go very slowly and stop at .300 and mark that number on the degree wheel, now keep rotating the engine clockwise past max lift and stop at .300 on the closing side of the lobe and mark that number on the degree wheel, Now lets say the first Number you marked on your degree wheel was 78 thats your IVO and your second number was 154 thats your IVC just for example of 154 you take 154 add the 78 to 224 then divide by 2 and you get 112 thats your Intake Lobe Centerline say you want it at 108 for better low end torque you would need to Either move the crank gear with multiple key ways to 4* advanced and redo the process, Remember Parts are far from perfect they have Certain Machining Tolerances built in that only the manufacturer can control and it can vary from part to part, especially timing sets, Just Food For Thought, Hopefully my jiberish is understandable i made it as simple as i can, FWIW dot to dot should work ok but you will always be leaving power and torque on the table, not just 2hp either, Goodluck and put that Cam in at a 106* ilc you'll love the torque!

00Silv4.8

iTrader: (10)

holy giant paragraph battman!

just line up your timing marks and get a real tune you'll be fine. Engine tolerances are actually on the bigger side

for the record: when I put the cam in my 4.8 we didnt "degree" it, nor did we use some fancy timing set, it was the stock timing chain and gears with ~8x,000 on it. Then when I BUILT my 6.0, I was told it would be best to use plastigauge for the connecting rods because the crank was polished. I didnt do any of that, and the motor didnt knock and to my knowledge is still a beast in someone's garage. Call me crazy but I'd do it again in a heart beat. These motors arent that hard to deal with

SweetS10V8

iTrader: (4)

Thats the longest paragraph I have EVER seen!!! Do you seriously think any single person will read that?