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85GLHT-Omni
12-29-2005, 06:24 PM
Anyone know how to correctly install one of these for something other than 0 degrees?

They have don't have the 3 and 9 o'clock slots to align the cam cap parting lines. What I do is put the cam straight up with the zero keyway, then remove the sprocket and slide it on the 4 degree keyway (or which ever you wish). I also assume this is 4 degree of advance, can you retard cam timing with this sprocket?

BadAssPerformance
12-29-2005, 06:28 PM
Is that the MP sprocket with the 5 keyways? I thought that with that and the offset cam keys that you gould get any degree setting needed cause you can use the 5 slots, 5 degree keys, and also skip a tooth forward or backward on the belt as needed...

85GLHT-Omni
12-29-2005, 08:14 PM
I thought it was one or the other...5 keyway sprocket or adjustable keys. Maybe this is why I have 150PSI compression but only 12 inHg vacuum.

Stratman
12-29-2005, 09:08 PM
I thought it was one or the other...5 keyway sprocket or adjustable keys. Maybe this is why I have 150PSI compression but only 12 inHg vacuum.

Isn't that the gear that they failed to stamp which keyway sets it to what degree?

85GLHT-Omni
12-29-2005, 09:58 PM
No the degree is stamp on each keyway...what it doesnt have is the parting line holes at 3 and 9 oclock for absolute proper alighnment.

Other than Fidanza, who else sells an adjustable cam sprocket (square tooth) for 2.2's?

ShelGame
12-29-2005, 11:01 PM
I've got that one, too. What you do is, set the cam sprocket up at 0, and roll the engine over to TDC, then un-tension the belt and change the sprocket to the advance you want (make sure the intermediate and crank don't move, the cam has never moved on me; it helps if the belt doesn't move, but it's no biggie if it does), then set the belt back on pulling as much tension on the FRONT side of the belt as possible by hand (it'll have a little more slack than the 0 setting). Put the belt into the closest groove. Then re-set the tensioner. It should be correct.

85GLHT-Omni
12-30-2005, 12:12 AM
Thanks, that's what I've been doing. In fact I use tie-wraps to secure the timing belt to crank and intermediate shaft while I play with the cam timing. What advance are you running and what kind of vacuum do you pull?

Like I mentioned, 85 TII conversion with a 287 head, 12degrees base timing, 4 degree advanced cam timing because I'm running a 1990 roller cam instead of teh 1985 slider cam.

Prior to the TII conversion, idle vacuum was a healthy 18 inHg, now it's 12 inHg. Compression is upwards of 150 psi across all four cylinders.

I'm just checking to see if I screwed something up and I'm missing something here. No complaints on power or driveability...to much torque for just one wheel, though.

Do true-adjustable cam sprockets let you adjust cam timing without untensioning the timing belt...allowing you to experiment with cam timing without the hassle of pulling the accessory belts and such?

86Shelby
12-30-2005, 12:50 AM
Do true-adjustable cam sprockets let you adjust cam timing without untensioning the timing belt...allowing you to experiment with cam timing without the hassle of pulling the accessory belts and such?

Yes, they do. Sometimes you still have to hold the cam stationary as the spring pressure will try to turn it after you move it, but other than that you have it right.

ShelGame
12-30-2005, 05:23 PM
I'm starting with 4* advanced (118* Intake CL) on an '88 TBI roller cam. Stock CL is 122*. I'll let you know how it runs once the engine is back in the car...

detobias
01-07-2007, 08:32 PM
Like I mentioned, 85 TII conversion with a 287 head, 12degrees base timing, 4 degree advanced cam timing because I'm running a 1990 roller cam instead of teh 1985 slider cam.


wouldn't that be 4 degrees "retarded" ?

thus the Mopar cam gear would be nice because you could use the 4 degree *advance* keyway to bring your round tooth cam back to "straight up" ?

I ask seriously because I am running almost the exact combo - 91 TBI cam on my 85 TII conversion Omni ; seems like it has a very soft bottom end and lots of high-rpm power which would be consistent with a *retarded* cam - correct ?

{remember the original 83.5 Shelby Charger carb'd HO motor had the cam *retarded* 4 degrees to increase top-end power ...}

puppet
01-07-2007, 09:15 PM
I've got that one, too. What you do is, set the cam sprocket up at 0, and roll the engine over to TDC, then un-tension the belt and change the sprocket to the advance you want (make sure the intermediate and crank don't move, the cam has never moved on me; it helps if the belt doesn't move, but it's no biggie if it does), then set the belt back on pulling as much tension on the FRONT side of the belt as possible by hand (it'll have a little more slack than the 0 setting). Put the belt into the closest groove. Then re-set the tensioner. It should be correct.Seems like you'd need to reposition the cam a bit ... after you reinstall the sprocket in the corresponding keyway .. to get your advance/retard positioned correctly ... right? If so .. the belt can't move but you'll need to nudge just the cam forward or back a bit. ... or, if your good, nudge the crankshaft before pulling the sprocket?

contraption22
01-07-2007, 09:32 PM
Did you see that TU has Fidanza cam sprockets on special this month for only $80?

turbovanmanČ
01-07-2007, 09:55 PM
Running a roller cam on a square tooth combo gets you 4 deg RETARDED

Yep, adjustable's are awesome, 1 min adjustsments. Its great for the track, at the dyno etc. I love mine and will never run an 8valve without one again.

BadAssPerformance
01-07-2007, 11:25 PM
Did you see that TU has Fidanza cam sprockets on special this month for only $80?

Now that's a deal! :thumb:

JuXsA
01-09-2007, 05:49 PM
just bought one last night.... ill let you all know how it looks when I get it.