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99 Suburban 5.7 cam upgrade timing issue

  
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99 Suburban 5.7 cam upgrade timing issue

 
jerszone jerszone
New User | Posts: 3 | Joined: 12/13
Posted: 12/26/13
01:14 PM

New to the fourm, great job
I recently rebuilt a 5.7l vortec with a 08-466-8 comp cam, 26918 springs, dart vortec heads w/1.6 aluminum roller, headers, for stock ca emissions and Pcm tuned. I installed the distributor one off and engine ran with some extra fuel burn, moved distributor in with 0 cmp and now get starter turn back, hard to start, like its out of timed. Question is why truck starts good with distributor gear off 1 even 2 teeth off but right on does not? Thanks  

dond1965 dond1965
New User | Posts: 6 | Joined: 12/13
Posted: 12/26/13
03:42 PM

because the computer try's to time it, its not like an old centrifigal advance unit. it sure sounds like you have too much ignition advance. get a repair manual and learn the proper way to time it your self. i personally have never worked on one of those. like all things, i'll bet its easy once you know the trick... good luck to you.p.s. try reposting this at chevy high performance, ol waynep7122 can help im sure. this site is all but dead.  

jerszone jerszone
New User | Posts: 3 | Joined: 12/13
Posted: 12/26/13
04:53 PM

Thanks for the response, ill try that other site and double check everything again  

wayne712222 wayne712222
New User | Posts: 33 | Joined: 10/13
Posted: 12/27/13
04:16 AM

vortec distributors do not control ignition timing...

they contain the CAM SHAFT position sensor...

the crank shaft sensor is in the bottom of the timing cover..

Vortecdustributerinstal

Vortecdistributerinstal

Vortecdistributerinstal

Vortecdistributeralignm  

dond1965 dond1965
New User | Posts: 6 | Joined: 12/13
Posted: 12/27/13
09:24 AM

and today i learn something else from you, thank you very much sir for your time/effort!! i sent you a pm, if you have the time PLEASE respond, gooday to ya!  

jerszone jerszone
New User | Posts: 3 | Joined: 12/13
Posted: 02/10/14
05:58 PM

Distributor is correctly installed, cmp at 0.3, the starter turns back and idle is erratic  

wayne712222 wayne712222
New User | Posts: 33 | Joined: 10/13
Posted: 02/11/14
12:18 AM

you have the cam card...

using  a breaker bar.. with a socket on the crank bolt.. where does stop where the second rocker arm drivers side start to move..  note the timing marks on the crank..

compare to the cam card.??? is there any chance that the cam timing chain marks are off one tooth.. it really should not make a big difference.  its the relationship between the crank and the distributor alignment.

can you set the crank damper marks to TDC... pull the crank sensor then see where the forward edge of the reluctor step lines up in relation to the center of the crank sensor... does it line up at the beginning of the hole.. the middle of the hole or the other side of the hole..  use a mirror.. or your little finger if you are sure that nobody cranks the engine while you are probing..


don't forget.. you are looking at the inside of the timing cover and reluctor below.
Vortecv8reluctor Zps0e31b9cd

take a look at the end of the crank sensor.. make sure its NOT hitting the reluctor wheel.. i have heard that can happen and will will make things run crazy..




how much wear is on the distributor drive gear..???
Worn Vortec Distributer Gear Zpsdd0ba9f2

how much wear is in the distributor shaft bushing???
Vortecwornbushing Zpscfb5b0fc 1

how is the inside of the cap and rotor..??

Vortecv8distributercap  

tuffnuff tuffnuff
Moderator | Posts: 4 | Joined: 12/10
Posted: 02/12/14
09:32 AM

Great post Wayne

Smile  
When The Flag Drops.,.

tuffnuff

The Bull ***t Stops.,.
tuffnuff

P. Engineer, Engine Builder

wayne712222 wayne712222
New User | Posts: 33 | Joined: 10/13
Posted: 02/14/14
11:20 PM

i have another idea..

Is it the Correct damper???

can you verify actual TDC verses Timing pointer/damper marks..


this is for some of the earlier damper styles..

Chevybalancermarks


Sbc400damper Zps7b6410dd

or the damper inertia ring has slipped...