Thread: i dont get it....

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howdy yall.
so my first post, dont bash me too much..
i got a 88 350 tbi block and heads with a rpm preformer intake and eldelbrock carb.
fist off.. fires right up.. minor primming needed. runs great revs just fine.. once i put it in gear and take off it starts to stumble around 1500 rpm then its back to running fine again.. i rebuilt the carb thinking thats my issue...and it didnt change a bit.. i checked the fuel pressure ...holding 7lbs on the nose. i replaced my whole distribitor, top to bottom..didnt phase it.. timming at idle is happy around 5 or 6 ...WTF nothing i have done has effected the way its running on the take off..( dead stop to WOT or just normal take off) its the same evey time.
then i noticed a tick...i thought exaust leak... couldnt find it.. maybe a rod...doubt it.. not that kind of KNOCK..rocker arms..so i chek them.. tightened them 3 diffrent times.. zero lash and 1/2 turn... heres the catch... it dosent always tick.. some weeks its ust fine.. then some days it starts up in the am ticking and dose fine in the afternoon....

well sorry for typing out a half a book here jsut im at my last resort. i cant pull the motor just yet but thats my next step i think..
any advice or infor would be great.

Fuel pressure is too high, drop it to no more than 5psi. You want high volume not high pressure.

Timing set with vacume hooked or disconnect?

Maybe hanging advance weights?

I would bet that you have vacume advace hooked up and without it you are retarded timing, as rpm comes up on acceleration idle vacume drops and timing retarded temporarily un til distributor weights start to advance timing----

will do.. not sure who told me 7 but either way .

timming was set with the vacume off. i have had 3 diffrent people check my timming, 2 with advancers and 1 with my old plain jane timming light. and like wise we check the timming with the vacume dissconnected.

i feel as if its somthing extreamly stupid and minor... Jerry you pointed out a very simple mistake that very well could have happened anybody.. today when i get homw i will be pulling the valve covers and pushing on rockers to see if any of them are loose.. and also to see if any of the lifters are weak ..
question .. stock flat tappet lifters.. how hard should it be to push down to the colapsed position??

Originally Posted by mitchpdavis

will do.. not sure who told me 7 but either way .

Different carburetors will tolerate different fuel pressures, but as Ken said, the Edelbrock runs best with 4 3/4 to 5 psi. More pressure than that can unload the needle and seat in the bowl and allow the pump to blow raw fuel into the intake manifold, creating a tuning nightmare for you. Carburetors are not like EFI, more pressure WILL NOT make more horsepower.

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Is the harmonic balancer the original unit?
The elastomer does break down with heat, vibration, age and the outer rings have been known to move.
Take a close look and see if the material looks good between the inner and outer parts.
You could also set # 1 cylinder at TDC and verify the timing marks line up..

My car has a leaking heat crossover between the manifold and head which is blocked off by the manifold, ticks after the car warms up a bit as the manifold is still cold and after the manifold warms up it quits ticking, evidently sealing after the manifold expands, the thing drove me crazy trying to find it as I thought it was the rockers as well. Not sure if this would be a problem for you or not though. Matt

yes sir.. i will try this out today.
i am just getting back to town today so i will be able to mess with her again.

Originally Posted by 34_40

Is the harmonic balancer the original unit?
The elastomer does break down with heat, vibration, age and the outer rings have been known to move.
Take a close look and see if the material looks good between the inner and outer parts.
You could also set # 1 cylinder at TDC and verify the timing marks line up..

i think i am replacing the cam, lifters and timming chain in the next few weeks. im told by many other people that it sounds like a flat spot on the cam, maybe a dead lifter.. so to rule this out i will first change my fuel pressure, then fully examin my balancer. (i have a vortech motor i may just pull the balancer off it and use it) then on to the cam. due to the nature of my job i will be in and out of town so my time will be limited but i will for sure let you know of any results.