Took it for a drive today and the knocking sound continues. Driving me insane now. Sounds great idling but as soon as I take off it bogs down and makes a racket. Letting it cool off now to double check all vacuum hoses for the umpteenth time. Next step is to ditch the 1.6 rockers and reinstall the 1.5 factory ones. If it runs great with the 1.5s I may personally take tehe 1.6s to Iowa and throw them through the window of the place I bought them from.

 

I replaced the 1.6 roller tips with stock 1.5s on the exhaust side last night. Ran much better but still not the way it was before this fiasco. I will put the intake stockers back on tomorrow.
The only thing I can come up with that makes sense is that a previous owner put a cam in at some time and the 1.6s don't go well with it. That would shock me thougfh since it seems like every dang thing else on the car is original from 1989.

 

So is the knocking sound gone or any less?

 

The knocking almost went away but the power is not completely back. I get the feeling when I switch out the intakes it will be back good as new. Sucks since so many do this mod without trouble.

 

Changed the intake rockers to stock 1.5 and there is still a knock at WOT. The knock is coming from the top end of the engine. If I retard the timing (with wire discinnected) down to zero or 2* retarded the knock is better but still very noticable. I had some parts to use so I changed out the knock sensor and esc module. No difference. Any other thoughts on what the heck happened in a simple rocker replacement? I guess I'll go back through the vacuum once again and make sure I don't have a leak.

 

Since you're convinced the noise is emanating from the valve train, all this comes under the heading of "Valve train geometry".

Attention to Detail; Attention to Detail, and, yes, ATTENTION TO DETAIL.

Ask yourself: "What would cause the knocking/tapping sound?"

Answer: Two or more things hitting each other.

Now the question becomes "What two or more things are hitting?" Once you find those your problem can be solved.

Many, if not most, times, things hitting each other leave witness marks; leaving little shiny areas that show where the contact is being made. I'd first look for those.

Next I'd look for the required clearances between two parts. To do a thorough investigation I'd begin with the area where the lifter rides on the camshaft then work my way UP. If the clearance spec is, say, .030" make SURE you have that much.

If you pay scrupulous attention to detail, at some point you'll find where two (or more) parts are hitting and/or the clearance isn't sufficient. Unfortunately there's no way we can identify exactly where the problem area(s) is since we can't "see" your setup.

CompCams and others list those areas that MUST be checked for the proper clearance so following their advice is an excellent idea. You'll need to slowly cycle the valve train completely through all its movement phases, checking as you do.

Also, steer clear of the reduced preload settings that so many inadvisedly recommend. Go with factory recommended preload settings to avoid introducing yet another variable. This 1/4 turn or less of preload recommendation needs to die a slow and painful death once and for all.

Just changing parts, in the hope of finding a cure, ain't gettin it done.

Hope this helps.

Jake

 

I have kind of moved away from thinking it is rocker related since it is still going on with the stock 1.5 rockers. Having the timing set 6* advanced like the factory does it then hooking up the timing wire gives a bunch of knock. Setting it back to zero or 2* retarded takes a lot of the knock out but it is still there. No knock in either situation at idle or a slow takeoff. It only knocks under WOT. Replacing 21 year old parts didn't seem like a bad idea even if it didn't fix the knock. The knock sensor was rusted up pretty bad.
Thanks for the help.