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3sgte cam degreeing issue

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Hi everyone.

recently purchased an installed a set of GSC S1 camshafts for my rev2 3sgte.

I have attempted to degree them today to find getting a straight shot at the lifter buckets is impossible.

I believe I’m getting inaccurate readings on my degree wheel given my dial gauge is no where near perpindicular.

the main issue I’m having is the measured degrees being uneven between opening and closing events measured at 1mm.

Does anyone have any advice on this?

im pulling my hair out trying to come up with a solution.

Picture of what you have to work with?

Have you tried a lever-type dial indicator such as something that looks like the picture on this page:

https://www.fullyinstrumented.com/types-of-dial-indicator/

I did consider these, but most only have a range of less than 1mm. I’m needing to measure close to 10mm of travel.

There is obviously thousands of 3sgte motors that have been degreed, I can only assume given the cam completely obscures the lifter bucket the readings have been very approximate.

as an example I should be seeing EVO@41.5bbdc, I’m getting 39bbdc.

EVC@0.5btdc, I’m getting 4atdc.

If it was an equal amount off on both sides I wouldn’t be worried.

Mira my first time doing this so maybe I’m overthinking I just don’t want to trash my freshly built motor.

Perhaps they are done with the head off the engine, and the cam position at TDC is marked somehow. Or can you make a piece of sheet metal (a "C" shape) that goes around the cam, so you keep that in contact with the buckets, and measure it's movement.

So if you are measuring when the valves open and close, isn't that the first 1mm or so of travel?

Yes that’s correct.

taking readings as per the cam card at 0.04/1mm lift opening and closing.

I might see if I can find some material to make something as you mentioned thanks

OK, I may be over-simplifying this, but if you can get contact with the follower for the approximate travel required, but with the DTI at an agle, why not use simple trig' to calculate the actual DTI travel that will correspond to the 1mm required? You can use a high-school protractor, if required to eyeball the angle.

There may be some confusion over the DTI lever type David mentioned# - the "range" is for one rotation of the needle, the actual travel is normally considerable more as the needle can rotate numerous times. the total travel is typically 10mm - but that would need to be confirmed with the suppier as it doesn't seem to be specified? It isn't really that relevant, though, as you're really only interested in the first couple of mm, anyway. I've used versions where the 'lever' was 90 degrees to the line of the body, but that was many years ago and don't recall details.

Another option which 'should' work (never tried it) is to use a DTI with a 'foot' adaptor - I've use them for other applications, but no idea of source* - on #4 to measure the drop from the high point of the cam' lobe? At TDC it will be 180 degrees opposite #1.

# https://www2.mitutoyo.co.jp/eng/useful/catalog-2020/html5.html#page=411

*Ah - https://www2.mitutoyo.co.jp/eng/useful/catalog-2020/html5.html#page=401

After much fiddling and frustration I have managed to get the cams to within +\- .5 of a degree.

everything is spinning fine so I’ll take it forward from here as being good.

thanks for the suggestions and advice.