| Go back to previous topic | | Forum name | Performance/Engine | | Topic subject | update on my cam gear adventures | | Topic URL | https://forums.2gnt.com/dcboard.php?az=show_topic&forum=i5&topic_id=24378 |
24378, update on my cam gear adventures Posted by VX100, Jun-03-02 12:33 AM
Just to keep everyone who helped me out up to speed, I finished my car (with the1bill's help) at something like 4:30 or so on saturday morning. So, after that I just got ready to go racing that morning (gates opened at 8:00, it's at lest 1 hr and 45 minutes away). Driving that long after being up all night with NO sleep is not fun, but somehow I did it.
Some things about the cam gears, Bill and I compared the AEM gears to the stock gears, and the timing marks ARE different! Bill and I measured them up, and put marks on the AEM which match the marks onthe stock gears (not too hard to do, but something you have to be careful with to make sure the marks are accurate).
This time we followed the procedure exactly (thanks for the help with that everyone! :) ) got the tension right, got all the marks to line up, put the tensioner in, turned the car over two times, everything else still lined up so we knew we were good.
We started the engine after getting most stuff together (just in case it was messed up) and had the gears set to 0, the car idled normally but I didn't let it warm up so we could actually work on it (sot he rpms were at about 1000 or so). We put everything together and tried to set the gears. The intake cam is TOUGH to set due to the tension on it. The best we could manage at first was +4 degrees advance onthe intake, and -2 degrees retard onthe exhaust.
NOTE: make sure you keep the bolts in the cam gears when you adjust them, so you don't push the gears too much out of phase and break your valves! The bolts will bottom out at 10 degrees (on the cam shaft) if you push too far.
The car idled well at first, but once it warmed up and dropped to 800- 850rpms and the idle got a bit lumpy. No where near as bad as before, but still a little loping in the idle. So we tried to turn down the intake cam. We got it (after much trying) to +2 degrees advance on the intake (and didn't touch the exhaust) and the car idles just fine. I have checked it a bunch of times since the install, after the engine has gotten hot and the rpms are about 800-830 or so, and I put a load on the engine by keeping the air conditioner on at idle, and the idle is still fine, no loping at all.
As for performance, the butt-o-meter says I'm getting more power at 4000 rpms with the +2/-2 cam gear settings, but I can't be sure about the top end. (4K rpms doesn't help at the drag strip) The car seems to be running strong, no problems at all.
When I went racing saturday, it was too warm of a day to run good 1/4 mile times. My best run of the day was a 15.77, but my mph (without spinning the tires that badly) was at 88-88.2 mph so I was getting slow 1/4 mile times, but rather high mph, especially for the 85 or so degree weather. (the mph on my best run is 88.4 on a colder day)
I am guessing that the higher than expected mph indicates the cam gears are giving me more top end power (I did easily pull on a 2001 Jetta VR6, I'll post in the war stories when I get a chance ;) ), but the day was too warm to compare to the other days I was racing. I might get a chance friday to go racing at night (6:00 to 10:00) where it will be cooler and closer to the temperature on other days I have raced, and that should make for a better comparison to see how much the cam gears have added for power, and how muvh of a 1/4 mile improvement they have given me.
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24379, RE: update on my cam gear adventures Posted by Michael_97RS, Jun-03-02 10:00 AM
Glad you finally got it timed and good to go. I look forward to some good runs with you in those.
Una salus victus.

Michael J. Kulaga e-mail: Michael_97RS@2gntDSM.zzn.com aol IM: MJKulga http://highlander.dsmpower.com/
All motor in the making.
Injen CAI, 55mm TB, P&P Intake Manifold, Hooker Header, GS-T Muffler, AFX UDP, S-AFC, 8.5mm Magnecor Wires, Crane Fireball HI-6DI2, SS Clutch Line, NRG Susp. Motor Mount Ins., FU/RU/RL STBs, TSW Blade 17x7.5, Bridgestone Potenza RE730, Front KVR Cross-Drilled Rotors & Carbon Fiber Pads
To Be Installed: P&P Milled Head, Rear Disc Brakes, Rear KVR Cross Drilled Rotors & Carbon Fiber Kevlar Pads, SS Brake Lines
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24380, Very nice... Posted by Skrilla, Jun-03-02 01:38 PM
...I'm sure youre excited. you definitely got some extra power with those settings and tha AFC.
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24381, RE: update on my cam gear adventures Posted by jsupetran, Jun-12-02 04:24 PM
great time imo...it gives me hope for my slow a$$ 98gs. have you gotten your rs dino?
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24382, RE: update on my cam gear adventures Posted by MuRiX, Jun-13-02 01:22 AM
Your suspicions pretty much match what my dynos told me years ago. I gained 1-2hp below 4k, gained about 5hp peak at 6k, and gained 10hp above that with the same settings of +2/-2. Only other mods were intake/exhaust. Any more extreme and you lose bottom end and gain more top end which is what you should really be doing for racing anyway. After a while you get pretty good at changing the gears quickly. Only loosen the bolts a little when adjusting and get some proper mechanics glove so you can play with them at the track.
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24383, RE: update on my cam gear adventures Posted by VX100, Jun-14-02 06:29 AM
Thanks guys, for now I'll keep them at +2/-2 until I can get some dyno time (as we know every car is a bit different)
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24384, RE: update on my cam gear adventures Posted by damasta, Jun-14-02 09:57 AM
Yo, if you want more top end, what would you increase/decrease, intake or exhaust? What would be a good setting for more top end? Also, how do you adjust the gears once the cover is back on? Do you reinstall the timing belt cover after install of the gears? Do you cut a piece of the cover off? Is it safe, for the timing belt, to have it directly exposed to crap falling in there? Anyone have any pics of what their setup looks like?
Thanks, and sorry for all the questions.
Coo' alex_ries@hotmail.com


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24385, RE: update on my cam gear adventures Posted by VX100, Jun-15-02 01:46 AM
Advancing the intake and retarding the exhaust is what you are supposed to do for more top end power.
I had cut a hole in the timing belt cover to keep the cam gears exposed. No it is really never a good idea to have the timing belt exposed (that's why it has a cover :) ) but you need to in order to adjust the gears. I did not want to leave the whole cover off so I cut a hole out of mine, which is tough to do without an air tool with a durable cutoff wheel (dremmel tools just don't do a good job of it).
I can get a picture (or I think The1Bill might have one, I don't remember if he took a pic or not) but I'm still having problems getting the digital camera to do what I want for some reason.
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24386, RE: update on my cam gear adventures Posted by eclipse804, Jun-15-02 06:35 PM
Mine has had the whole upper half of the cover gone for the past 2 years. The entire cam gears are exposed and a bit below the gears too. I have never seen a car with adjustable cam gears leave the cover on without cutting out some sort of hole for adjustment. It's really a matter of no choice. Mine broke when they took it off so that's why I just left the top half off.
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24387, RE: update on my cam gear adventures Posted by VX100, Jun-16-02 06:22 AM
I cracked my timing belt cover when I was cutting it. Thank God for JB weld ;)
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