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I've been reading thru the various threads on exhaust cam gears and trying to understand the whole topic. Basically most people seem to slap them on... set the gear to -4 and off they go. Unless they add on other parts and do tuning... then they can get a different optimal value.

I'm just hoping you guys can let me know if my understandings on the subject are correct. So basically adding an aftermarket cam gear does not necessarily increase the amount of power you have overall... but shifts where the strong part of the power curve is. So by putting on an exhaust cam gear I am giving up low end torque for better high end power?

For any of you that have done this mod... what negatives have you noticed? Are the gains obvious?

When considering your reply... keep in mind that I am considering the effects of the exhaust cam gear only... not the gear plus cam shafts, etc.
 

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absolutely no noticeable gains. however the acceleration is more consistent and i felt like it improved the drive due to this. maybe you gain a few HP. this is the best thread to read about this topic. http://my.is/forums/f88/diy-cam-gear-install-383203/?highlight=diy+cam+gear Hope this helps.

Also cam gear without cams, i can think of NO negative aspects. Car pulls a little harder and more consistently. Very subtle mod.
 

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I've got the camshafts so that adds a variable.

I noticed that the power band continues to the redline without dropping off or running out of steam. So I feel the car pull harder from 3500 to the redline. The compression is increased so it makes sense that it should do this. I notice no losses down low.

The downside is a slightly rougher idle and a jumpier throttle so it is harder to drive the car smoothly. It is particularly abrupt when I suddenly lift off the throttle at high revs.
 

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absolutely no noticeable gains. however the acceleration is more consistent and i felt like it improved the drive due to this. maybe you gain a few HP. this is the best thread to read about this topic. http://my.is/forums/f88/diy-cam-gear-install-383203/?highlight=diy+cam+gear Hope this helps.

Also cam gear without cams, i can think of NO negative aspects. Car pulls a little harder and more consistently. Very subtle mod.
I can't speak for this mod in NA form but when boosted, stock compression, I picked up almost 18rwhp from a exhaust cam gear.

There are definitely gains, its a simple install, and most motors are most responsive right around (-)3.5~4.
 

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the exhaust cam gear is made to give you adjustability with aftermarket cams with higher lift, however you can SLIGHTLY tweak the stock cam adjustment by retarding the timing by -4, this number is generated by people testing it out on stock cams.
since theres no other variables like boost -4 would be pretty much the optimum level adjustment for a stock cam engine.
im pretty sure flow-rate would some how effect the setting however i dont think you would want to invest money on having a exhaust cam gear adjusted to your 300 dollar header and y pipe combo tuned with a SAFC lol.
so in closing, slap one on retard to -4 and dont expect much.

correct me if im wrong, i've been wrong these days.
 

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Cam gears are used to adjust valve overlap. Generally NA cars benefit from more overlap and boosted cars from less overlap (cause the boost escapes).

Here's an article from the integra people about it:

Cam gear tuning basics - Team Integra

Ignore the articles little rant about not copying other peoples cam gear settings. If you have similar mods copying settings is fine.
 

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absolutely no noticeable gains. however the acceleration is more consistent and i felt like it improved the drive due to this. maybe you gain a few HP. this is the best thread to read about this topic. http://my.is/forums/f88/diy-cam-gear-install-383203/?highlight=diy+cam+gear Hope this helps.

Also cam gear without cams, i can think of NO negative aspects. Car pulls a little harder and more consistently. Very subtle mod.

A cam gear will have no negitive effects on a stock NA IS. I installed one on a members car and he loved the outcome and the gained performance. you may not feel a gain in power but like said abouve ^^^^ it will make the power and torque curve better and more consistant. I didnt think it hurt the power in the low RPM's, infact I think adding the cam gear gave more power down low and made the car perform better in all RPM ranges.

Also it has been teasted at +2 with the brian crower 264 cams. That member on here feels that it gave more power at the +2 setting then at -4. I have yet to see dyno papers of this result but i think the best setting for the cam gear is -3 to -4. In the brian crower 264 cam owner FAQ thread I did a little write up of a few different cam gear positions and the out come of it.
 

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I'm glad I found this thread.

Does anyone have any actual documented proof of gains on a stock engine / IS while using an actual chassis dyno? (Butt-dyno does not count)

Did it effect your fuel economy?

How does it effect daily commuting?

I am getting ready to do the 90k service and I am considering installing an adjustable exhaust cam gear. I'm just not sure if the price of the gear is worth the small gains.
 

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I'm glad I found this thread.

Does anyone have any actual documented proof of gains on a stock engine / IS while using an actual chassis dyno? (Butt-dyno does not count)

Did it effect your fuel economy?

How does it effect daily commuting?

I am getting ready to do the 90k service and I am considering installing an adjustable exhaust cam gear. I'm just not sure if the price of the gear is worth the small gains.
if you're looking for HP gains, the cam gear on its own will not help you in that department. i'm sure it's documented somewhere but the bottom line is you could be seeing in the ballpark of 2-4 HP gained if you play with the tuning. I set mine at -4.

I didn't zero out the odometer but I didn't see any noticeable difference in the fuel economy.

As far as daily commute I felt that it improved the feel of the acceleration throughout the RPM band. Basically the car felt smoother when I accelerated. Please note that I have an Automatic Tranny. So +1 for daily commute.

I think there is a Titan for sale here in the thread for like 140 or something. So it all depends on the size of your pocketbook. If you're planning on doing cams one day I would definitely throw one of these in. If not, you'll have to decide if the money makes sense for you.

Good luck.
 

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if you're looking for HP gains, the cam gear on its own will not help you in that department. i'm sure it's documented somewhere but the bottom line is you could be seeing in the ballpark of 2-4 HP gained if you play with the tuning. I set mine at -4.

I didn't zero out the odometer but I didn't see any noticeable difference in the fuel economy.

As far as daily commute I felt that it improved the feel of the acceleration throughout the RPM band. Basically the car felt smoother when I accelerated. Please note that I have an Automatic Tranny. So +1 for daily commute.

I think there is a Titan for sale here in the thread for like 140 or something. So it all depends on the size of your pocketbook. If you're planning on doing cams one day I would definitely throw one of these in. If not, you'll have to decide if the money makes sense for you.

Good luck.
Sebastian,
Thank you for your prompt reply! I have an 03 Sport Design AT. I'm also considering doing a 'ground kit' as well. Supposed to help with shifts.

Please describe 'playing with tuning' for me. Are you suggesting something like an AFC or piggyback controller? I can tune Nistune, Haltech, and PFC's, but currently I'm running the stock PCM. This is my DD, so I would rather not be doing much along the lines of 'tweaking', if possible.

My current 'mods' are a Joe Z intake with drop-in filter, and a HKS CF axle-back exhaust. All original o2's, header, etc.

I check my fuel economy every time I fill up. ;) I'm still around 24.3 MPG currently.
 

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if you're looking for HP gains, the cam gear on its own will not help you in that department. i'm sure it's documented somewhere but the bottom line is you could be seeing in the ballpark of 2-4 HP gained if you play with the tuning. I set mine at -4.
You should be seeing 5-10whp across the power band. Das did an analysis of the exhaust cam gear back in the day, but it looks like he's not hosting the results anymore.
 

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You should be seeing 5-10whp across the power band. Das did an analysis of the exhaust cam gear back in the day, but it looks like he's not hosting the results anymore.
on a stock car there is no way you will get 10HP in gains. this would be the best N/A mod for the price is you could get 10 horses for 150 bucks. Not a chance.
 

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If i sell you one for $300 would you believe it? :lol:

$ != performance

I can an intake for $15 that gets 5-10whp, I guess that means I can produce the best bang for the buck for the IS300 in my garage in an hour.
 

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does it really idle rougher?
Yes it will. Without the gear I can hardly tell that there is any lope with the BC. Set at -4 there is definitely lope, no question. But frankly it is very very minor...sort of in the territory of an older M3 or M5 which means it is very nice and subtle IMO because the Lexus thing is far to smooth and quiet for me.

Even with the stock cam it will be rougher but by less to the point that you may hardly notice it.

The factory tune is compromised for emissions and smoothness. Increasing overlap for more power is a really old trick even on old American cars (I was talking to a colleague who is and older guy)

Oh the other penalty is that if you retard it too much you will bend your valves.
 
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