[SENTRASER]

This is very frustrating. I just installed a set of S3's, and the idle is lopey as hell. I had a mishap with the chain tensioner, so I thought that maybe I skipped a tooth up top on the cams; nope, there's 20 links between the timing marks and they line up at 10 and 12.

So I tried andreas' trick; lined up 10 and 12 up top and try to look down below to see what the crank pulley said. It says aprox -5º from the -5º mark. So I look up top, it looks like it isn't quite at 12, so I put the crank at 0º and the exhaust cam dowel looks like its at 12 again.............ugh, I'm so frustrated. Why oh why is it low on power and lopey as a stroked 350?

On a side note, I ran last night at the track and ran a 16.4, then a 16.2. It seemed to fall on its face on high rpm's, I checked the timing and it was at somewhere around 25-30...so that would explain SOMETHING. Also, I can't get the idle to be consistant worth a ****. I need some help, I'm tired of taking the valve cover off and putting it back on in such a short period of time. PLEASE HELP!

 

[AaroNX]

Advance the chain on the gears one tooth, rotate the motor several times to make sure there is no interference, and see how it does. That's what I did, and it's alot better now, and mine did the same as you say falling on it's face.

 

[jer_760]

I have skipped a tooth on the crank before, it CAN happen.

 

[SENTRASER]

I have skipped a tooth on the crank before, it CAN happen.

When it skipped a tooth on the crank, was it off 20º? Mine is only off, seemingly, 10º negative of 0º. I'm just having a real hard time telling 12 at 0º and 12 at -10º ; or I guess just 12 on the exhaust cam is real confusing to me......

I zip tied the cam sprockets when I chaneged them out, so I dont think thats the problem...but I did put the timing chain tensioner back in upside down when I put it in the first time...and it leaked oil everywhere, so I guess it could have moved then... I count 20 links between the timing marks on the cam gears; I guess both of them could have moved 1 tooth retarted. thus making the cam gears 10 degree's off...that would explain why it ran 'okay' at 25 or 26ºbtdc, which is what it was set at, and then I put it at 15ºbtdc and now it falls on its face....uhgh.... So confusing. I just dont want to advance them both one tooth and fock something up.

The gears actually lined up with the timing marks on the chain, if only they would have put an acess hole in the timing cover to see the corresponding mark on the crank...

 

[SENTRASER]

Ugh.........I give up for tonight.

 

[eric96ser]

When you installed the cams, did you make sure the crank was at 0?

 

[AaroNX]

Mine is only off, seemingly, 10º negative of 0º.

That's how mine was.

 

[SENTRASER]

When you installed the cams, did you make sure the crank was at 0?

Yes, at one point, but I installed the tensioner upside down and it sqirted oil everywhere. I also zip tied the cam sprokets. I dont think the cams skipped timing because I got the colored marks to line up, but I couldn't see down at the crank side. From what Andreas Miko said, if you skip a tooth on the crank it would be 20º off. Its so hard to tell up top when it is at 12. Its running better now, I set the distributor in the middle and am about to check the timing and idle. I'm also gonna replace all my vacuum lines, see if that helps...I found one vac leak, and replaced that hose, had to go get some more. The idle is still lopey as hell, and unpredictiable. It seems to pull hard now though, but I really need to get the header installed and a deicent intake, all I have now is stock header with a blown secondary and zip tied k&n panel filter.

 

[SENTRASER]

That's how mine was.

If I was to adjust it 10º the cam timing dots would be on the middle of a roller, rather than on a flat link...so I that was a bit disconcerning.

 

[AaroNX]

You're not understanding. The teeth on the gears are 10 deg, the teeth on the crank is 20.

 

[SENTRASER]

I know the links up top are 10º and the links on the crank are 20º . I'm just saying that the dots up top are bot lined up with links and are 20 rollers appart...so that means if the timing IS in fact off it HAS to be 20º and not 10º. See what I'm sayin now?

 

[KdubL]

hope this works out for you...

 

[AaroNX]

I know the links up top are 10º and the links on the crank are 20º . I'm just saying that the dots up top are bot lined up with links and are 20 rollers appart...so that means if the timing IS in fact off it HAS to be 20º and not 10º. See what I'm sayin now?

Mine was fine up top too. Hell it was fine at the bottom, till I checked to make sure the motor was actually at tdc.

 

[SENTRASER]

Right, but my cams timing marks line up, and I tried moving the cam gears two rollers, so they would line up with the links again, and they were definatly not at 10 and 12 at either advancing or retarding them.

 

[SENTRASER]

145-150 PSI across all cylinders. Still got low vac, any ideas?

 

[Cheezit]

Finding True Top Dead Centre
Good info.