If the rockers are too tight it is holding the intake valve open slightly, allowing the flame to travel back up through the intake. I've seen it happen before. It's rocker adjustment pure and simple. I've fought this exact same battle before.

The valves can be held open far enough to stop you from getting the compression you need and still not hit the pistons. It's also not noticable to the human eye that the springs are compressed slightly even when they are "fully closed" If you can't grab the rocker and jiggle it slightly then it's way too tight. It shouldn't be really loose but you should be able to move it.

 

got the heaters going in the garage...i'm determined to get it running today.

anyone wanna give a crash course on how to correctly adjust them?

i have a haynes, i have the facotry manuals and i also have the gmpp instructions but they are all a little different.

remeber now, i'm a 21 yo that is pretty stupid

 

just read your pm nathan....nvm on the rocker adjustemnt....i will do it the way you stated in there


thanks a lot guys...i'll let you know what happens later

 

The instructions I sent you should get it "damn close." If anything they will be a little bit too loose, which is OK because at least it will start and run. You can then tweak them from there.

I would also leave the belt off and the alternator rolled up out of the way until it does actually run. You can run an LT1 without the belt with no problems since the water pump is gear driven. Just make sure your battery is good and hot. It'll save you some trouble should you need to tweak the adjustments further.

Good luck, keep us posted!

 

should i try starting it with the covers off?

 

Absolutely. At idle it'll take several minutes before the oil starts to make a mess. You can also watch it and make sure that the oil is flowing to the top end like it's supposed to.

 

[QUOTE=Nathan Plemons]If the rockers are too tight it is holding the intake valve open slightly, allowing the flame to travel back up through the intake. I've seen it happen before. It's rocker adjustment pure and simple. I've fought this exact same battle before.

Thanks Nathan for sending him instructions, I'm to old school on valve adjustment and I'm sure I would get him all goofed up It seems this is one of the most common problems after a cam change I think this has happen to all of us a one time or another. I hope this takes care of your start problems blackroselt1

 

more questions...any percautions while starting with no alternator? if i turn the engine by hand, using the nut on the crank, will i tigthen that more?

got everything off ready to adjust

 

Well your crank bolt will tighten to the point where it starts to want to turn the crank. If you're worried about it at all just pull the spark plugs and that will allow the engine to turn very freely.

 

it started for like 3-5 seconds and then it died....wouldn't start again.

nathan - i'm starting on the intake valve (exhaust is totally compressed) and tightening the adjustment nut till it stops with my fingers, giving it a little more with the wrench and then holding it while locking it. i then rotate till the intake is compressed and then do the exhaust.

what am i missing/doing wrong?

 

my .02...

when i did this, Phil at Advance Induction told me to loosen the rocker arms WAY up and get the thing started... don't even try to adjust. I had it so loose that I could that there was considerable play on the rocker arm.

It will sound absolutely horrendous but it will start, and Phil said that it won't damage anything...

This way, you have confirmed what the problem is.

After I got her started, I then did the "tighten until quiet plus a 1/4 turn" method.

Key seems to be to confirm what the problem actually is. If she won't start after that, you know it is not a compression/rocker arm issue.

 

Did you tighten the inner nut first? This is "backwards" of what convention but it serves two purposes. By tightening it down first it limits how much you can tighten the nut itself. It also makes sure that it won't back out.

Basically if you adjust the nuts to where they're perfect and then just try to tighten down the allen nut in the middle they'll back out every single time and you'll have to re-adjust them every month if you drive it at all.

 

i reread you directions and tighten everything the right way. it started for a while with the stock chip and would die after a little while. i then started it with your chip and it ran fine. i put it all back together and now it won't start. loosened the covers to see if thats the prob but still no go...what gives?

 

Cant the opti be 180 out??

 

Throwing any codes when it dies?

Since it started and ran at all that rules out the opti.

 

no codes

 

Best I could say then would be start with the basics again, fuel and spark. If it was running without the valve covers on and you actually turned the key off there is no reason why it shouldn't run when you put the valvecovers / alternator & belt back on.

Now if it was running and died of it's own accord then there might be something else going on.

The only thing I could possibly think of with the valves at this point is the following. Say you got the rockers adjusted close enough that it would run. You started it up and it ran ok until the lifters started to pump up, which started to hold the valves open just a tad too far and hence it died. It died as a combination of things, the tune was so far out of whack and it wasn't making good compression. You put my chip in and the tune was close enough that it fired. It then ran and allowed the lifters to pump all the way up. It was able to compensate enough while it was running to keep it running. After you shut it off though it has no idea what it needs to do in order to start it back.

This is one of the reasons why I don't recommend adjusting the rockers while the engine is running. It is easy to get them too tight and although it will keep running it can be hell to start it back, and it's costing horsepower. It may start back after your lifters bleed down a little bit.

I've also had a no start condition caused by a failing ignition control module, but this usually sets a code and again results in a no-spark condition. Why my control module went south it would work until it got hot and then it would crap out. This could take 5 minutes, it could take 30 seconds. I'm still betting on the rockers. Worst case you can do as TankerVette suggests and make them all looser than crap. It will sound terrible but then you'll know.

The worst thing you can do right now is get discouraged. You're thisclose to having a running car and I promise you that you'll be happy with the results. Adjusting the rockers is a trick that only comes from experience. I know, I've fought this same battle many times myself until I finally found a method that works for me so that's what I swear by. Other people have their own methods that works for them. You'll find yours soon enough and suddenly it will "click" and you'll be able to adjust a set of rockers with your eyes closed.

 

I'm trying to get a video uploaded that might help somebody. Seems like somebody finally caught onto my 200 MB web page though so I'm having to clear space before I can upload it.

 

No word today... He either off'd himself or he got it to work and he's enjoying his new found horsepower.

 

Let's hope he is enjoying the HP and not knuckle busters