i started up my rebuild HSR 350 today, and we got it all timed and whatnot, and its like popping back up through the intake...like backfire....so we figured that a valve wasn't closing all the way or something, so we backup the screws on the rocker arms a half turn...still popping, can't figure out what the hell it could be...anybody got a suggestion? bad lifter maybe?? i don't know...the timing is at 6* advance, if that matters...

 

Fresh motor? Or just INtakle swap.

If just intake swap, no reason to play with the valves...probaly more due to timing or plug wres routing.

 

fresh engine....crank was ground, new crank/cam bearings, new pistons/rings...redone heads, HSR intake, 276HR cam...the whole 9 yards..she sat awesome at idle yesterday with the stock prom in it, but as soon as we switched to the new one, she didn't want to idle back down....now she won't even fire up this morning....

 

Sounds like you found your problem then

Time to burn a new chip

 

well its a learning block computer, so maybe i need to put the chip in, and try to keep it running so it can relearn everythign with the new chip....but the chip was burnt just for this application, so I don't see the problem....i'm gonna try keeping it running right now, and see how it does...

Plus, I still dont' know what can cause that ticking, other than maybe one of the lifters are collapsed? or perhaps a few of them?

 

she loves the new chip...awesome throttle response....i'm impressed, however, it has a real sparatic idle, like 800-1500, like it starts idling down, then it thinks its gonna clonk out, so it idles back up, its been running like 5 minutes on the new chip, you think its still learning?.....still popping tho

 

Check for vacuum leaks and exhaust leaks

It's a new motor, we all manage to miss a vacuum line, or "that one vacuum line that looked ok so I didnt replace it" hehe.

 

nope no vacuum leaks....made sure I had all of those ...good news tho, NO POPPING ANYMORE!!! I don't know if the new chip did it, like the injectors weren't firing at the right time before or what, but with the new chip it runs like a charm....maybe one of the lifters were pushed up or collapsed and it took this long to bust loose, I have no idea, but it runs real good now, and tonight we are gonna set the rockers when its running, so they are set perfectly...I thought I had a huge problem when it was ticking...