Degreeing a new camshaft

[Hyboost]

Heres the skinny, I just went through my 86 GN. New head gaskets, cam, t49 turbo, 009 injectors, ultra chip w/thumbwheel. fuel pump, etc, etc,I got the cam from Postons, a 107 with 202/202 duration 269 lift. I was advised not to install a double roller, cuz they can hit cover and cause spark retard, so,,, I put a all steel stocker in only goes on 1 way, 1 keyway. The car idles kinda rough, and I dont think she spools up fast enough, not much power on the low end. my question is, should I have degreed the cam instead of putting it in at 0 tdc? I'm looking at the spec sheet, and it says all specs are given at 4 adv. Could putting it in stock position cause the rough idle and less than great power on low end? Builds tons of boost at around 2800, but below that kinda doggy. Anyone put this cam in their car, better results? I still have the stock convertor and rear end gears. Thanks, Ken, Buffalo NY.

 

[frankg]

If the cam is 4 deg. retarded now that will cause loss of low end power. Frank

 

[Hyboost]

Thats what I'm not sure of, is the spec on the cam sheet4 advanced when the dots are lined up or do I need to do something else? Ken F.

 

[frankg]

Usually its advanced in the grind so you can go dot-dot but if you didn't check it then it may be off. You should always degree the cam for a high performance engine, or at least check it to make sure it's close. Frank

 

[TurboDave]

Symptoms you describe could also be cause by a mis-installed/adjusted cam sensor.

 

[Hyboost]

Thanks for the info, I'll pull it out, reinstall and reset where it should be, I guess "close enough wasnt!

 

[MSDGN]

Also there is too much concern as to the location of the reluctor ring window when seating the end of the sensor to the cam gear...all the instructions I've seen state to point it towards a specific spot like drivers side...5 clock...etc...the position has no bearing on anything other than where the electrical connector will end up once it's set...do note the position though because it can be used to verify the engine is at TDC next time you have to do something with the cam sensor...the most important thing is to make sure the engine is at TDC on the compression stroke before starting the procedure...alternatively you can also start the procedure with the engine at 25 degrees ATDC...doesn't really matter...

 

[TurboDave]

Originally posted by icepicker62
Thanks for the info, I'll pull it out, reinstall and reset where it should be, I guess "close enough wasnt!

More specifically, don't get it set at 180º out. That's what causes the symptoms you described.

 

[Hyboost]

Will recheck that tonight, thanks again, Ken.

 

[gofstbuick]

I have that cam in my car. The idle is smooth and the turbo spools just as good as stock if not better. I degreed the cam. It required no adjustments. I installed it straight up. I still have my cam card, if you need any specs off of it. But mine did spec out exactly as stated on the cam card. I'm using a dbl roller chain, and no problems here. I know most suggest using a single row. But mine runs fine and I'm pushing 30000 plus miles on this rebuilt engine.