hi im tnol86 im new to this forum this is my first post im 20 yrs old im not an expert on cars but love them in general and know my older chevy cars pretty decent but as i said im definitly no expert

so i done my first rebuild of a chevy 350 bored .40 over

first let me start by saying that i used a tbi engine and swapped to carb everything on the car is stock i used some heads out of a old van they are 882 heads had them checked cleaned valve seats redone and new valve guides all done at machine shop

one of the biggest questions i have is i did not change the cam i used the one in the motor i was told this cam wont produce enough vacuum for carb is this true? i am not running a vacuum booster or canister of any sort as well

also can somebody give me a good walk through of rocker arm adjustment while the engine is off

ok so today i went for 1st start set the #1 piston at tdc and timed my dist (not perfect timing on setting in dist but close enough it shouldnt matter) so when i go to start i have oil pressure just from whirling the starter (all the way up to 30psi) im also getting gas and fire but the best i can get out of the motor is little hits it sounds like its not trying to fire on all cylinders and wont even try to start at all besides the few hits it will put out(note these hits are constant and not erratic) my plugs are new and giving out nice blue sparks and there should be nothing wrong with the carb i took it off my 305 which was running great untill about 200k+ miles and a heavy foot made it start knocking from what i believe to be a spun bearing but anyways i have double checked my timing and the carb is squirting gas and i have no open vacuum ports my only two ideas are the questions above but i was told even though the cam wont put out enough vacuum it will still start so im wondering if my rocker arm adjustment is wrong and not letting enough gas and air in anybody got any ideas? any help or suggestion would be greatly appreciated

thanks, tnol86

p.s. my fuel pump is a mrgasket 7psi carb electric pump also the car this is going in was a carbed car and ran great with the 305 so computer trouble is out of the question and all plugins/connectors are same also im using a q-jet

 

Best/quickest way to adjust valves reasonably accurately, is the "EOIC" method.

Adjust ONE valve at each position of the engine. Remove the spark plugs. Turn the engine by hand by hand, in the direction it runs, until a cylinder's exhaust valve is just beginning to open. (Exhaust Opening, "EO") At that point, adjust the intake valve. Loosen the rocker nut until the push rod is loose; hold the push rod in your fingers; tighten the rocker nut slowly while moving the push rod up and down between the lifter and the rocker; tighten just to the point where the slack is taken up and there is no longer a gap that the push rod can be moved; tighten ˝ more. Do all 8 intakes that way, in the firing order. (2 full revolutions of the engine) As you turn the motor the last couple of times, watch for intake valves that reach peak opening, and begin closing; after the last intake is adjusted, turn the engine until an intake valve has just gone through that cycle, and has just reached fully closed; ("IC", Intake Closing) at that point, adjust that cylinder's exhaust valve as described above. Go through the firing order again, doing all the exhausts. (2 full engine revolutions)

DO NOT try the "Chilton's" method of setting the engine in one spot and adjusting a bunch of valves, then setting it somewhere else and adjusting a bunch more. WAY too many will be partly open, and their adjustment will consequently be WRONG.

Once you get that done, remove have your assistant "bump" the starter while you hold your finger over the #1 plug hole. Have him/her stop when you feel compression. Turn the engine by hand, looking down into the plug hole, until you see the piston approach the top. At that point, check the distributor. Adjust the "timing" until the little teeth of the moving star wheel line up with the stationary ones. Make sure the rotor is pointing at the #1 plug wire. If not, put #1 wherever it's pointing, and put the others in, in the firing order, CW around the dist cap.

Sorry to hear about the heads; that'll pretty much guarantee that the motor won't be competitive. Start saving up for some good ones.

Can't say about the cam until you tell us what it is.

 

thanks im gunna try that out today figured i would take the valve covers off and turn it over and see if my valves appear to be opening properly

the heads eh im not looking for anything competitive figured i need to learn how to build a stock engine before i go tryin to build a performance one can i asked though why you think they are no good though they have 1.94 int and 1.56? exh not sure on the cc of the chamber but hey anything should be better then the 78 305 that when i looked it up was rated for 165hp and i believe 180tq?

also when you say adjust the timing untill the little teeth of the moving star line up with the stationary ones do you mean the points under the button? ive honestly never heard anybody say this when doing dist timing so you might have to explain that one alittle better

as far as the cam i cant tell you the exact lift or duration becaus i dont know all i can tell you is that the complete bottum end of this motor and the cam is a 1988 chevrolet 5.7l and that the engine came out of a 88 2wd 1500

 

well got the first start a few minutes ago ran through my rocker arms as you said and retimed it and she fired right up ran for a few seconds roughly and died(forgot to switch my fuel pump on) started it back and she fired right up again with 60psi oil pressure but was idling a little rough had a slight miss to it and alittle bit of a clatter but i havnt adjust my rocker arms while its running either hopefully that will straightin out my rough idle and miss and get a vacuum gauge stuck on her to see if my cam is making enough vacuum even if it doesnt all in all im happy with my first rebuild and want to say thank you sofa for the EOIC adjustment method and all your help

 

Amazing,almost word for word.
Adjusting Hydraulic Lifters for Proper Preload



Since hydraulic lifters can compensate for thermal expansion of the engine, the adjustments can be made with the engine cold; hot adjustment is not necessary.





In order to adjust the preload the lifter must be properly located on the base circle or “Heel” of the lobe. At this position the valve is closed and there is no lift taking place.You will need to watch the movement of the valves to determine which lifter is properly positioned for adjusting.

1. Remove the valve covers, and pick a cylinder you are going to set the preload on.

2. Hand rotate the engine in its normal direction of rotation and watch the exhaust valve on that particular cylinder.When the exhaust valve begins to open, stop and adjust that cylinder’s intake rocker arm. (Why? Because when the exhaust valve is just beginning to open, the intake lifter will be on the base circle of the lobe, the correct position for adjusting the intake.)

3. Back off the intake rocker arm adjuster and remove any tension from the pushrod.Wait a minute or two for that hydraulic lifter to return to a neutral position. The spring inside the lifter will move the pushrod seat up against the retaining lock if you give it time to do so. (If you are installing brand new lifters they will be in the neutral position when they come in the box.)

4. Now spin the intake pushrod with your fingers while tightening down the rocker arm.When you feel a slight resistance to the turning of the pushrod, you are at “Zero Lash”. Turn the adjusting nut down one half to one full turn from that point. Lock the adjuster into position. The intake is now adjusted properly.

5. Continue to hand turn the engine, watching that same intake. It will go to full open and then begin to close.When it is almost closed, stop and adjust the exhaust rocker arm on that particular cylinder. (Again, when we see the intake almost closed, we are sure that exhaust lifter is on the base circle of the lobe.) Loosen the exhaust rocker arm and follow the same procedure described before in steps 3 and 4 to adjust this rocker arm.

6. Both valves on this cylinder are now adjusted, and you can move on to your next cylinder and follow the same procedure again.

Tech Tip courtesy of Crane Cams

But from Crane cams.Opps!!!.