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This a quick DIY for those of you that may have thought this was possible without taking apart the whole front of the engine. There may have been a thread about this in the past but I couldn't find one.
I have had these GReddy cam gears for about 2 years now and was waiting to do the whole works with the Kevlar belt and new idler and tensioner that I have also had for about 2 years. That requires about a days worth of time to take everything apart and put it all back together again. I don't have that kind of time these days, nor shop space to do it in, wifey has the garage right now.
As I was doing all the pre-driving seasonal tidbits to put some insurance on the car and start driving it again I really started to look at the cam gears and wondered if I could just slip the stockers off and slip the GReddy's on in their place. Short answer is hells yea. The only big caveat is that you must have some slack in the timing belt. If you have a fresh belt that's a little tight I don't think this will work, my belt is a little old-ish and I can pull the belt up between the gears and create some slack.
Pics....
Note the CAS^^^^
Now, sharp eyed readers will notice that the exhaust cam appears to be advanced a bit, both by the timing hash mark and the fact that the CAS in the first photo is cranked all the way over to one side of it's adjustment. The cams are 8.9mm lift so I think they are old HKS 260 sticks. I suspect that the CAS driver in the cam wasn't put in there "straight up" because of the skewed position of the CAS. I played around with the cam timing both with the gear and skipping the belt a tooth and the exhaust is both advanced about 1 deg and the CAS is quite a bit out. At least I can work around it.
I will adjust the intake cam first to get the most cranking compression then retard the exhaust until it starts to fall again. The last move will be to advance the ex cam back to the point of highest cranking compression. That is a good starting point for tuning and should give me the most off boost torque and quickest spool.
As far as time? It actually took me 10 min longer to type this up than it took to do the whole job. Intake was about 5 min. and the exhaust was about 15 min.
Hope this helps someone who wondered if it's possible to do it this way....
Jon.
I have had these GReddy cam gears for about 2 years now and was waiting to do the whole works with the Kevlar belt and new idler and tensioner that I have also had for about 2 years. That requires about a days worth of time to take everything apart and put it all back together again. I don't have that kind of time these days, nor shop space to do it in, wifey has the garage right now.
As I was doing all the pre-driving seasonal tidbits to put some insurance on the car and start driving it again I really started to look at the cam gears and wondered if I could just slip the stockers off and slip the GReddy's on in their place. Short answer is hells yea. The only big caveat is that you must have some slack in the timing belt. If you have a fresh belt that's a little tight I don't think this will work, my belt is a little old-ish and I can pull the belt up between the gears and create some slack.
Pics....
Note the CAS^^^^
Now, sharp eyed readers will notice that the exhaust cam appears to be advanced a bit, both by the timing hash mark and the fact that the CAS in the first photo is cranked all the way over to one side of it's adjustment. The cams are 8.9mm lift so I think they are old HKS 260 sticks. I suspect that the CAS driver in the cam wasn't put in there "straight up" because of the skewed position of the CAS. I played around with the cam timing both with the gear and skipping the belt a tooth and the exhaust is both advanced about 1 deg and the CAS is quite a bit out. At least I can work around it.
I will adjust the intake cam first to get the most cranking compression then retard the exhaust until it starts to fall again. The last move will be to advance the ex cam back to the point of highest cranking compression. That is a good starting point for tuning and should give me the most off boost torque and quickest spool.
As far as time? It actually took me 10 min longer to type this up than it took to do the whole job. Intake was about 5 min. and the exhaust was about 15 min.
Hope this helps someone who wondered if it's possible to do it this way....
Jon.
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