did a search and cant find much, can anyone i n here help?

heres the story, did a rebuild on a k20a2 in a 01 jdm dc5.

the engine was let overheat due to a burst rad and it then warped the head!

i had the head skimmed and replaced all the rings/seals gaskets etc!

now heres the problem, after putting the engine back together, it wont time up right!

when the 2 cams are aligned properly and the crank is at its mark, the chain has far too much slack on the non-tensioned side allowing the timing to move out of sync once tensioned up!

i have come to two conclusions!

1. the head was milled too much giving the chain extra slack. ( in which case a thicker headgasket might fix my problem?)

2. the chain is stretched!

i know number 2 is not commmon but not unheard of either, is there anyway of measuring the chain or has anyone else experienced the same problem??

thanks in advance!

 

anyone??

 

ps there is a K forum in at the very top.

 

The chain is possibly stretched. I have seen it in one other setup a couple months back... Order a new chain and you should be just fine...

 

This drove me nuts as well, so I had a friend come over to witness what I was working with and he said "that's just the way it is..."

"Okaay" I thought, took his word, we slapped it all back together and to my amazement, it fired right up and idled normal. I connected to the AEM (car has a 1070 box) to find my sync dead on.

To elaborate, my engine & timing chain had ~190,000 miles on them (for what that's worth) when I had to re-time it after an exhaust cam swap.
I'd lock each cam to TDC using the locking pin holes Honda provides.
Using the indicator on the block, set the crank to TDC
Install tensioner with paperclip locking it back (no tension)
Put the chain around the 3 sprockets, lining up the 3 punch marks with the 3 colored links
Pull the (paperclip) out of the tensioner
And with zero slack, the crank would roll forward ~ 1 full tooth with the cams still positively locked at TDC and all 3 links aligned with the corresponding punch marks.

I chalked it up to chain stretch in my case. BUT, from the experience I'm now ridiculously quick at pulling front covers off K's and setting chains AND, since my sync was spot on, learned most of my chain stretch must have occurred between 0 and ~90,000 miles because that's when I put the AEM on it (I'm the original owner of the car) and set the sync position.

 

i must check the milage tomoro morning, its 1 in the morning here now!

^^^ thats sounds alot like what im getting sc

the thing is, i tried it like that, fired it up but it was hard to start and would not run great ( like it was off timing) and also there was a slight rattle too!

im just praynig it didnt damage the valves!!!

i wonder if maybe a combination of stretch and the milling of the head is making my case worse??

i will post pics tomoro too!