ok i will retry the EO/IC method to adjust the valves hopefully it fires tomorow as I am going to wait until i have the guideplates installed to adjust anything to avoid doing the job twice.

 

Ok i got the guideplates on today and readjusted the valves as per the IC/EO procedure and still no start, the car acts as if the timing was 180 off, it sounds as though all the compression/fuel/explosion, are coming blowing out of the exhaust. I am at a loss and have no idea where to go from here, the timing gears are lined up correctly as I have been asked that a few times any ideas guys?

 

Have you verified that you correctly routed and connected the spark plug wires? Your profile says you're running a LT4 HotCam, so that tells me you're running an Opti-Spark, right?

Are you sure you positioned the Opti correctly when you installed it on the engine?

With the Opti installed you wouldn't be able to see the numbers telling you which plug wire goes to which spark plug, so you may have mis-connected one or more of them.

Do you have a diagram that shows which plug wire goes where? Where it plugs in on the Opti and which spark plug it goes to.

I've read that the Opti on some engines can be installed wrong, while others can only go on one (the correct) way.

Sounds like something simple; now it's just a matter of figuring our what it is.

Jake

West Point ROCKS!

 

Sounds to me like its 180 out. You could have lined up the timing marks with #6 at TDC instead of number one.

 

A non-vented opti's drive will only allow it to go on one way.

 

Okay, so I assume his is the non-vented version. If that's the case, how could he install it 180 out?

How about posting a detailed way he could check to see if his Opti is installed correctly. Any diagram(s) you have would be helpful too.

I know this has come up recently on the Corvette Forum and one of the responders posted both the plug wire positioning on the Opti and the correct mounting orientation.

Thanks for your feed-back and participation.

Jake

West Point ROCKS!

 

I put the wires on looking at a diagram found on the net, the only way the timing could be 180 out is if the two dots were on opposite ends of the gear in other words i had the dimple on the cam gear directly above the dimple on the crank gear, they were pointing to each other. I'm absolutely 100% positive the cam timing is right.

 

Also i know i have the opti on correctly can the cap be installed 180 out? I'm pretty sure there was a pin in there that made sure it was on correctly but i can't remember for sure.

 

BS. Tell that to all the people who have forced them on wrong. Happens all the time.

All this "180 out" talk is usually used when referring to conventional SBC distributor types.

Early optis go on like this.

This animation will show you the exact orientation of cam (including dowel pin), cam and crank gears as it goes through the firing order.

This shows you where to put all the plug wires.

 

Okay, if you're absolutely sure, . . .

Here, before tearing into the engine again, visualize this:

Think of the face of a clock as you're facing the front of the engine:

Now remember that the #1 and #6 pistons go up and down in unison. The exactly match each other in their up and down movement. This difference is what they're doing.

When one is up on the COMPRESSION stroke, the other one is up on the EXHAUST stroke, and vice-versa.

If the crank gear dot is at 12 o'clock (meaning the #1 piston is at TDC) AND the camshaft hear dot is at 6 o'clock, the #6 piston is on the compression stroke.

When the Crank gear dot is at the 12 o'clock position AND the camshaft hear dot is also at the 12 o'clock position then the #1 piston is on the compression strike.

When the camshaft gear dot is at the 3 o'clock position, the camshaft is on the EXHAUST stroke for the #1 cylinder and the COMPRESSION stroke for #6

When the camshaft gear pin is at the 9 o'clock position, the camshaft is on the COMPRESSION stroke for the #1 cylinder and the EXHAUST stroke for #6.

Now, if you can remember where the camshaft pin was when you installed the Opti, that may help you know that the Opti was installed correctly.

If your Opti cannot be installed 180 degrees out, then the Opti installation can't be the problem.

If you're sure that the spark plug wires were connected properly, then that can't be the source of the problem.

BUT, if one or more of the lifter preloads was too tight, that would cause a no run, back-fire situation.

Are you also absolutely sure that each lifter was on the base circle of it's lobe when you found ZERO LASH and set the lifter preload.????

One or more set too tightly would definitely cause what you're experiencing.

I'm sure you know this, but the very first rocker arm at the front of the engine is EXHAUST, not INTAKE. In the past, some have mistakenly thought it was the intake and this threw off ALL of the preload settings. EIIEEIIE E=Exhaust; I=Intake

Hope this helps.

Jake

West Point ROCKS!

 

ok wow shoebox thank you so much for the animation, apparently i was told wrong about my timing by numerous people, the sad thing is I had no doubt in their advice, perhaps I will think twice about who I get my information from my timing is 180 out and I'm going to rip into it tomorow thanks for the help Shoebox.

 

Wow, I didn't know about that....

 

Nor did I, you learn something everyday!

 

Outstanding info! Much better than trying to explain it with just words.

Jake

West Point ROCKS!

 

Got it running today turns out i forced the opti on wrong stupid stupid, but thanks for all the help guys without you i would be lost thanks again.