I am planning on getting my car tuned again in a few weeks over at Evans tuning. According to their website, it's a great idea to get cams installed for added power. However after recent discussions via email, I was given this reply.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Evans Tuning &raquo;</TD></TR><TR><TD CLASS="quote">Joe,

Assuming this a turbo car (which I believe it is), the cam gears will not give you substantial gains. Jeff used to adjust cam gears and would see the gains on the dyno, but when it came time for the car to run at the track, you could not see the benefit of having adjusted the cam gears. The way dyno loads the motor shows a gain with a cam gear adjustment, but at the track the mph does not go up (meaning that in the real world, it doesn't gain power). All motor cars need cam gears because the after market cams need to be degreed into the motor combination, but OEM cams won't benefit and show little to no gain.</TD></TR></TABLE>

In response, I mentioned the article found here : http://site.mawebcenters.com/e....html

The reply was :

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Evans tuning &raquo;</TD></TR><TR><TD CLASS="quote">If that is a post by Jeff, the likelihood is that it was at least a year ago. Since then, Jeff has done a lot of experimenting on cars and with a turbo car it is better just to tune straight off the timing map and not touch the gears.</TD></TR></TABLE>

Please discuss.

 

the guys at evans tuning know their stuff. if youre doing a serious motor (600+whp) then i would run stock cam gears. the reason being is that if one of them slips in mid-race then you are eff'd. and since youre not seeing that much of a gain anyways, might as well run stock

 

I really think we should discuss this more, doing a search yields 95% of discussion goes back to this article from evans tuning. If he has changed his position on it, I think it's worth some input!


Modified by soulrider4ever at 9:28 AM 1/27/2007

 

I'd like to hear more as well.

 

You will not see substantial gains in power. But it will give you the ability to move your powerband around by adding or subtracting valve overlap. And you should'nt worry about your cam gears slipping, there are cars making a alot more than 600whp using them.

 

I bought cam gears based on information in this thread:

http://forums.evans-tuning.com...72b04

Also, isn't it more beneficial if you're running a log manifold like Inline Pro?

 

any tuners want to chime in?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by zeimbo &raquo;</TD></TR><TR><TD CLASS="quote">the guys at evans tuning know their stuff. if youre doing a serious motor (600+whp) then i would run stock cam gears. the reason being is that if one of them slips in mid-race then you are eff'd. and since youre not seeing that much of a gain anyways, might as well run stock</TD></TR></TABLE>

What about cars with stock blocks that are in the 200-300 whp range?

 

Cam gears will move your plot around and will be beneficial for traction as well as spool time. There is NO denying this. On a mild setup around 350HP I would spend that money else where.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by soulrider4ever &raquo;</TD></TR><TR><TD CLASS="quote">What about cars with stock blocks that are in the 200-300 whp range? </TD></TR></TABLE>
answer=
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by White Smoke &raquo;</TD></TR><TR><TD CLASS="quote">On a mild setup around 350HP I would spend that money else where.</TD></TR></TABLE>
much better things to spend your money on. if you get the right turbo, cams, and compression, you wont need to rely on cams to control your powerband. so its better to determine what best suits your power goals and usage of your car, and then sort out your budget.

 

if you're gonna have Jeff Evans tune your car, just listen to him...he knows his stuff . Looking at the graph, it did make more power everywhere w/ the camgear adjustments

 

I have stopped touching cam gears on FI cars unless they needed to be adjusted (i.e thicker headgasket, severely milled head/block, etc). There is a power gain on the dyno, but the mph isnt there at the track. The gains that I see are also only with the OEM ecu based systems, which means that the fuel/spark timing is getting altered with the intake cam positioning change. If i try to make the same adjustments with power fc, aem, fast, etc the large gains wont be there only a shift in the powerband (and very slight).

 

I have noticed the samething, the gains have not been anywhere the same when tuning an aem vs. hondata car even after setting the distributor back to 16, and if your not settting back, your just altering the whole timing curve.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boosted hybrid &raquo;</TD></TR><TR><TD CLASS="quote">There is a power gain on the dyno, but the mph isnt there at the track. </TD></TR></TABLE>

Where is all of the extra power going if it is not showing up at the track?

Could it be related to a difference in atmospheric conditions between the dyno room and the track?

Were the cars involved extremely traction or aero limited?

I just don't understand how you could see such a big gain on the dyno and not in the real world.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boosted hybrid &raquo;</TD></TR><TR><TD CLASS="quote">I have stopped touching cam gears on FI cars unless they needed to be adjusted (i.e thicker headgasket, severely milled head/block, etc). There is a power gain on the dyno, but the mph isnt there at the track. The gains that I see are also only with the OEM ecu based systems, which means that the fuel/spark timing is getting altered with the intake cam positioning change. If i try to make the same adjustments with power fc, aem, fast, etc the large gains wont be there only a shift in the powerband (and very slight). </TD></TR></TABLE>

Now it's starting to make sense, thanks Jeff

 

bump for a useful thread!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Type_RS_59 &raquo;</TD></TR><TR><TD CLASS="quote">Where is all of the extra power going if it is not showing up at the track?

Could it be related to a difference in atmospheric conditions between the dyno room and the track?

Were the cars involved extremely traction or aero limited?

I just don't understand how you could see such a big gain on the dyno and not in the real world.</TD></TR></TABLE>

The way that a dyno loads a motor is significantly different than real world/track conditions. Datalogs prove this in various situations i.e amount of boost, ability for engine to hold boost in particular gears, etc. You can even see more transmission breakage on the dyno, as opposed to track conditions. The only thing that i can conclude is that the dyno puts a much more significant load on the engine, and for whatever reason with the OEM ecus there is a gain but at the track with much less load the engine doesnt respond the same.

I can say that the a/f's off of the dyno are very consistent on the street, as well as at the track so the air quality in the dyno bay cannot be severly compromised. I do feel that in some situations cam gears are needed to degree the cams properly, and the gains will show regardless of what ems system that you are using since its a purely mechanical adjustment.

 

this is some good info that i have ben wondering about.

 

Jeff, what about log manifolds specifically? I have an Inline Pro manifold and plan to take my car to you for tuning when the time comes. Based on that thread you created, and especially this quote from you, I purchased ITR cams and BDL cam gears:

"My thoughts on the matter are that with log manifolds (this car was using one), scavenging goes to crap. Increasing the breathing of the engine opens up the engine with the higher exhaust pressure from running the log manifold, and allows for less exhaust gas contamination to occur. I noticed that the plugs burnt much better after the cam gear adjustment, as well as less ignition advance needed to be run (and not because of retarding the ignition timing since the intake cam was advanced)."

Do you think that my setup might be a situation where cam gears are beneficial?

 

my two cam gears are at different degree's...can anyone explain this?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Speed94 &raquo;</TD></TR><TR><TD CLASS="quote">my two cam gears are at different degree's...can anyone explain this?</TD></TR></TABLE>
Your tuner can...

 

what I meant to say was is it normal/ok to have it like that

 

Stock is 0-0

 

Maybe this question has been answered, but what is the difference between the way the honda ecu works for tuning cam gears than compared to the AEM and the others you listed.

Don't you reset the timing after adjusting the intake came no matter what EMS you are using. So why would the honda ecu be any different. Gosh, I hope this isn't a stupid question haha. Just tryin to make sense of this all.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Sprockets &raquo;</TD></TR><TR><TD CLASS="quote">Jeff, what about log manifolds specifically? I have an Inline Pro manifold and plan to take my car to you for tuning when the time comes. Based on that thread you created, and especially this quote from you, I purchased ITR cams and BDL cam gears:

"My thoughts on the matter are that with log manifolds (this car was using one), scavenging goes to crap. Increasing the breathing of the engine opens up the engine with the higher exhaust pressure from running the log manifold, and allows for less exhaust gas contamination to occur. I noticed that the plugs burnt much better after the cam gear adjustment, as well as less ignition advance needed to be run (and not because of retarding the ignition timing since the intake cam was advanced)."

Do you think that my setup might be a situation where cam gears are beneficial? </TD></TR></TABLE>

Would like a response for this also.