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-   -   TIMING ? AGAIN (https://www.racingjunk.com/forums/showthread.php?t=25303)

dparker 08-30-2009 07:58 PM

Jeff your not at tdc.....one time the piston is at the top the rotor will point at number 6 the next time the piston comes up to the top the rotor will be pointing at number1....thats because the cam turns 2 times for every turn of the crank.....

suicidebomb 08-30-2009 09:13 PM

dparker, I'm not trying to start a controversy, but the cam turns over once, for every two turns of the crank.

Where ya been, did you bring a note from your doctor? :)

JEFF69Z28 08-31-2009 02:09 AM


Originally Posted by wmeabates
What did you change in the jeting to improve the 60 ft? Give some info about the carb.Bill.

PUT 82 IN FRONT,HAVE 86 IN REAR, HAD 76 IN FRONT.CARB IS PRO SYSTEMS.950 HP BODY AND WORKED TO FLOW 840 CFM..AS OF FRIDAY THEY TOLD ME TO REMOVE FRONT POWER VALVE AND PLUG IT ,REAR IS PLUGGED,THEN PUT 90 JETS IN FRONT AND BACK,MAKE A PASS AND SEE WHAT HAPPENS.WILL TEST IT THIS WEEKEND.THIS COMPANY(PRO SYSTEMS)IS A WONDERFUL COMPANY,THEY EVEN AFTER AFTER HOURS NUMBER SO YOU CAN CALL THEM WHILE YOU ARE AT THE TRACK SO THEY CAN HELP.

wmeabates 08-31-2009 04:52 AM

Jeff,Let us know how you do with the help from Pro System.It's good to hear about someone helping with the parts they sell.Bill.

dparker 08-31-2009 10:14 AM


Originally Posted by suicidebomb
dparker, I'm not trying to start a controversy, but the cam turns over once, for every two turns of the crank.

Where ya been, did you bring a note from your doctor? :)

guess I need one.....trying to type to fast sometimes my brain is a sentence ahead of my typing......
I still think the reason that the rotor is pointing at 6 when he's on TDC on the harmonic balancer, is that the piston is on the exhaust stroke and not the compression stroke....lol

JEFF69Z28 08-31-2009 12:02 PM


Originally Posted by dparker

Originally Posted by suicidebomb
dparker, I'm not trying to start a controversy, but the cam turns over once, for every two turns of the crank.

Where ya been, did you bring a note from your doctor? :)

guess I need one.....trying to type to fast sometimes my brain is a sentence ahead of my typing......
I still think the reason that the rotor is pointing at 6 when he's on TDC on the harmonic balancer, is that the piston is on the exhaust stroke and not the compression stroke....lol

MY REV PROBLEM WENT AWAY WHEN I PUT THE OLD 6AL BOX IN ,NOW I HAVE A LEAN STUNBLE WHEN I MASH THE GAS,ATLEAST THATS WHAT MY CARB GUY THINKS I AM GOING TO YTRY HIS SUGGESTIONS THIS WEEKEND.

cepx111 08-31-2009 11:25 PM


Originally Posted by JEFF69Z28

Originally Posted by wmeabates
What did you change in the jeting to improve the 60 ft? Give some info about the carb.Bill.

PUT 82 IN FRONT,HAVE 86 IN REAR, HAD 76 IN FRONT.CARB IS PRO SYSTEMS.950 HP BODY AND WORKED TO FLOW 840 CFM..AS OF FRIDAY THEY TOLD ME TO REMOVE FRONT POWER VALVE AND PLUG IT ,REAR IS PLUGGED,THEN PUT 90 JETS IN FRONT AND BACK,MAKE A PASS AND SEE WHAT HAPPENS.WILL TEST IT THIS WEEKEND.THIS COMPANY(PRO SYSTEMS)IS A WONDERFUL COMPANY,THEY EVEN AFTER AFTER HOURS NUMBER SO YOU CAN CALL THEM WHILE YOU ARE AT THE TRACK SO THEY CAN HELP.


"950 HP body worked to flow 840" > Huh?

90 square sounds awefully big on the jets, I run a 1050 dominator on my 496 BBC and that's what I run.

If your having an off idle stumble make sure and check your acellerator pumps, you need a good squirt as soon as you crack the throttle.
That would be the first place I'd look before I started yanking jets and plugging power valvesand stuff even though I plug my power valves, just dont get ahead of yourself, you might cause another problem before you fix the original one.
Trust me on this one >Do one thing at a time and put back what DOES NOT fix the problem.
Be prepared when you go to the track to make several adjustments, bring plenty of tools, spare carb parts and it wouldnt hurt to have a resisdent guru handy for assistance and play with it till you get it right.
Goodluck, Cp




JMO>Cp

JEFF69Z28 09-05-2009 03:55 AM

90'S WERE TO MUCH BUT THE STUNBLE WENT AWAY SO I GUESS IT WAS MY CARB,PUT IN 88'S PLUGS WERENT TO BAD BUT CAR RAN GREAT PULLING THE FRONT WHEEL'S OFF THE GROUND AND LOW 10'S ALL NIGHT.MONDAY IM GOING TO CHANGE THE PLUGS AND GO DOWN A JET SIZE AND SEE WHAT HAPPENS.NOW I NEED TO FIND AWAY TO KEEP THE FRONT END DOWN.

OneBadGMC 09-05-2009 08:16 AM

Cepx...

Yeah, the 950HP carbs only flow about 810 CFM from Holley...

It's not commonly known, but yes, you get more factory flow from a 850 Double Pumper than a 950HP.


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