Timing mark question.

JAS · Post by **JAS** » Fri Apr 29, 2011 8:18 am

Well in the search for the cause of my under powered 4G63, I've just checked my timing.
Everything looks fine but i have noticed that if I put a straight edge across the factory cam wheels the timing marks don't all line up. Im talking about all 4 marks. The two in the middle line up but the two on the outside don't when I put the straight edge across them. Surely they should all line up??

Help!!

Post by **TOMSUN** » Fri Apr 29, 2011 9:53 am

You could get a degree wheel on the crank and put a dial indicator on the cam lobes, find the centreline of the lobe and check that it is dialled in to the cam card spec.
If you don't have a degree wheel a 360 deg timing tape might be ok.

I'd lend you my stuff, but its a pit of a drive/swim.

JAS · Post by **JAS** » Fri Apr 29, 2011 10:20 am

TOMSUN wrote:You could get a degree wheel on the crank and put a dial indicator on the cam lobes, find the centreline of the lobe and check that it is dialled in to the cam card spec.
If you don't have a degree wheel a 360 deg timing tape might be ok.

I'd lend you my stuff, but its a pit of a drive/swim.

thanks for the offer mate. But yes. Its getting to cold for that kind of swim now lol

Im only using the standard cams, so shouldnt need to go to the extream of degreeing them up.

I remember doing a cambelt on one of my old starions and getting it out by one tooth and it drove similar to the way my twincam one does now. Its slow to boost up and not making as much power as it should.
And after around 5700rpm the torque drops off very fast.

redzone · Post by **redzone** » Tue May 03, 2011 9:10 am

Yeah it's only the centre two that need to line up :) they use the same gear for intake & exhaust hence the 2 marks on each pulley

JAS · Post by **JAS** » Tue May 03, 2011 9:44 am

Thanks!!
I might just strip the front off the engine and double check everything anyway.

STARZILA · Post by **STARZILA** » Tue May 03, 2011 4:40 pm

The dowels on the cams go to the top

JAS · Post by **JAS** » Wed May 04, 2011 6:38 am

lol Thanks for your help mike!!! :beer

JAS · Post by **JAS** » Fri May 13, 2011 11:42 am

Looks out to me.

avandull · Post by **avandull** » Fri May 13, 2011 1:03 pm

What do the timing marks on the crank shaft pulley look like?

Looks to me like, if the crank is rotated very slightly clockwise, the marks on the cam gears will line up.

JAS · Post by **JAS** » Fri May 13, 2011 1:20 pm

Ive used a screw driver in the #1 cylinder to get TDC because the plate with the timing mark is a starion one. Which doesnt line up.
I can get the cam gear marks to line up if I rotate the crank but then the crank is not at TDC.

enthuzed · Post by **enthuzed** » Fri May 13, 2011 3:58 pm

Adjustable cams and dyno time will fix all of that...with a good tuner!

WANTSOM · Post by **WANTSOM** » Fri May 13, 2011 5:51 pm

Need to reset your cams and timing belt Jase. Then degree in the cams (if you can get hold of a set of adjustable cam gears)and watch the horsepower come on real strong :beer

avandull · Post by **avandull** » Fri May 13, 2011 6:47 pm

I have just took the top timing cover off and got a few shots. I have the VR4 harmonic balancer and timing cover, so it is easier for me to find TDC. I tried the screw driver technique to compare with the mark on the harmonic balancer, but I found it very difficult to get accurate.

I found a very slight error in my allignment marks. The first shot is where the harmonic balancer ends up when I line up the marks on the cams

The second is where the cams end up when I line up the mark on the harmonic balancer.

I believe my Starion is timed correctly, and the small error is due to stretch in the belt.

John196701 · Post by **John196701** » Fri May 13, 2011 7:28 pm

Jas
Rotate the crank around till both of the timing marks line, make a note how many degrees after TDC that the marks line up, this is how much the cam will be retarded, have you had the block decked and the head machined, what was the thickness of the head gasket compared to the standard gasket. Any time you machine a head, the natural thing on an OHC engine is the can gets retarded, it is more noticeable on a TC, having the cam retarded, you will notice a loss of power down low, but gain power in the top end, if it only a few degrees i would not worry about adjustable cam gears, it looks like yours could be 5+ degrees out

avandull · Post by **avandull** » Fri May 13, 2011 8:06 pm

I just had another look at your photos, it is out of alignment quite a bit.

I also think it is important to be able to set up the factory cams, before you should even consider getting a set of adjustable cams.
You should not cover up in-correct timing setup with adjustable cam gears.

Austarion

Timing mark question.

Timing mark question.

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