06GT

There are a few camshaft kits out for the S197, from most of the dyno graphs I've seen, they all cause a loss of power and torque below 4500 RPM. This doesn't really help to feel the advantage of the cams in a dual purpose DD/track car.

Are there any cams that actually make improved power and torque at a lower RPM range, as well as on the top end?

Ideally I'd like something that's making power starting at 2500-3000RPM, throughout the rest of the powerband.

Faber

keep your stockers. I have installed cams and the drivability went out the window. it does start making power at about 2800 rpms but the loss before that range is not worth giving up imho. unless you love dumping the clutch at 3000 rpm to get out of the hole i would say leave the stockers in. I am going to pull my cams out and put the stockers back in. the gain up high dosent make up for the loss down low.

70MACH1OWNER

Well I have to disagree with Faber. You just need to install the correct cams. I just put in these or I should say Brenspeed did on Feb. 15th. I lost nothing down low that I can feel but gained a bunch from 3500 and up. Also review this thread. I have posted my dyno sheet of before and after.



http://forums.bradbarnett.net/showthread.php?t=77538

Faber

I would love to see a dyno sheet that shows your power from 1200-3000 rpm, and a datalog that shows load/rpm/spark advance/manifold pressure so i can compare. I have had these bbr stage 1 cams on for a couple months now and can't seem to get the car dialed in to regain my power down low. I gained about 20 hp and tq up top but lost a bunch from the low end. It could be a tune issue, but it has been funky since the cams went in. granted they are higher lift and longer duration than the brenspeed ones.

how is drivability with the brenspeed cams? any loss off the line?

70MACH1OWNER

Johnny,
I really can't tell any difference at the lower rpm's with these Comp cams. Feels stock to me. In fact I should say I really don't notice any change at all until she is about 3-3500 rpm. Except a slight rougher idle. What I believe your problem is that those BBR cams have way to much overlap in them to create that great idle you have but it is this extreme overlap that kills you low end. The Comp cams were developed to increase top end HP only.

superman112

man I purchased the comp cams stages 3's .. the ones that require retainers and springs. Wish I would have held out for these news ones that Brenspeed has. I havent installed tyhe cams yet and if I had the newer ones I sure would be saving on the install. See... I guess it pays to wait.

70MACH1OWNER

You will get a few more ponies from those stage 3 cams and springs. That is for sure. But I know Brenspeed increased their charge for installing those cams to like $1400 because it is so time consuming.

Faber

Chris at BBR has told me that there is very little overlap at all. he said these cams were designed to compliment a blower or turbo since they dont have alot of overlap, only higher lift and longer duration. you think that is B.S.?

70MACH1OWNER

Maybe I should back up a little Johnny. I am not sure if the BBR cams have way more overlap or duration to them than the Comp Cams do. One or the other or both are your issue. They ground those cams for the idle and screw everything else. That is my opinion. Maybe they will work better with a blower I don't know. I just hope you get your problem worked out!!!
Scott

jwgroovin

I have the Stage IIIs and the tuner did everything possible to try to regain the lost torque down low--just wouldn't happen. So we focused on 4500rpm and up. Makes for a great track car. On the 4.6l aftermarket cams really don't come into their own there unless accompanied by ported heads. In all cases I've seen there is NO loss at lower rpms.


Just a note that a tuner in Florida appears to have evidence that the Comp Stage IIs actually outperform the Stage IIIs with the stock heads. Weird. Corral.net post I think...

John

Faber

I am going to re-install charge motion plates and see if that helps the low end power. if it dosent i am yanking them out. the thing that keeps me from yanking them right out is that doug was able to get the low end power back for 1 run on the dyno the other day. it went back to being funky down low, but it gave me hope that it might be able to be tuned out.

these are the bbr stage 1 cams which are not as radical as the stage 2 cams with the crazy idle. they are advertised as making power from 1500 rpm to redline.

yur1279

Any idea how these would perform if you were to supercharge the car later on?

NicksLime06

I asked the same question to the guys at Brenspeed last week. Here is what they said:

"The cams will work great with the supercharger as well. If you are close to
having the funds for the supercharger I would hold off on the cams and go
ahead with the supercharger. If it is going to be a while before you can do
the supercharger then I defiantly recommend the cams. The cams will add
more power than any other naturally aspirated modification available."

2006GT500

I had stage 4 comp cams and they performed great with my Procharger.