I am about to start my build on an 2006 g35 with the Rev-up engine with a g35R powerlab lab kit. I have been researching the availibility of aftermarket cams for this engine and the gains they produce. My goal is ~525-550 whp and maintain the midrange powerband of the g35r turbo. I would like any input from the guys with aftermarket cams on the rev-up engines as far as power gains, changes in powerband, etc. Are they worth it on this engine or should I spend the money elsewhere. Thanks

 

GTM and JWT both make cams for the rev-up motor. The GTM Stage 1 or the JWT S7R cams both will work for your stated hp goal. The JWT S7R cams are a little more aggressive as they provide more lift. I beleive the exhaust valve durations are fairly close, but the GTM Stage 1 cams have a little shorter duration on the intake valve, which should help keep a smooth idle.

 

Cosworth is another option. They make rev-up versions of both their ZK1 and ZK2 cams. However, I don't think you'll really need aftermarket cams to reach your power goals with the PowerLab kit, unless you want to extend your powerband beyond stock redline.

I recommend calling Intense and consulting with them about your cam options since they have more experience with the PowerLab kit than anyone else.

 

I have similar goals but using an 18g Greddy kit and was recommended Kelford cams by Injected Performance. Just started researching them last night. I didn't find anyone using them either here or G35driver.

 

anyone out there using the JWT C8R (revup)? Im comparing them to BC Stage 3 and they seem to have more lift, degree, etc, but was hoping someone running them and could chime in...

 

So you are going rev-up. It will be nice to have VVT on both the intake and exhaust.

You probably know this, but it is worth mentioning just in case you don't. The C8R has the same lift and duration of as the C8, but has a higher lobe separation angle before any cam phasing kicks in. 126 vs. 117.5 deg. The higher lobe separation will improve idle and low rpm operation. Since the rev-up has VVT on both the intake and exhaust, there is better opportunity to adjust the lobe separation angle to get optimum performance at any particular rpm.

So, if you can't find anyone with the C8R's, get some input from somebody that has the C8's, and just realize that you will have better idle and low rpm characteristics, but about the same high rpm performance.

CoachK has the C8 cams, and XKR has them in his car that is currently on Sharif's dyno. They are going into my new motor when it finally ships.

 

i have a full rev-up long block at my disposal(crazy slap yo momma steal of a deal..thnkx Roger@Japtrix).. at 1st i wasn't sure as to my cam choices with the rev-up vs the non-revup, but i been following/reading your posts on cams and compared the info made available (thankx). id rather have a nasty mid-upper rpm range than a low-mid rpm range. with my style of driving traction down low-mid is non-existent. the caracteristics of the BC3 and C8 seem to be what i need for my driving style and since BC doesnt make revup and JWT does its a no brainer, plus the C8's have more of lift, degrees, etc.. so better for me.. gonna do the complete cams/springs/retainers JWT and ferrera 1mm over valves... Thought JWT made valve too, but i cant find it on their site.

 

For your driving style the 1mm over valves will be good. I was talked out of going that route. At the time, the decision not to increase the valve size made sense based on my hp goals and my build at that time. Had I known I would eventually be stepping up to a 4.0L motor, I would have done it.

 

i have a guy with the Kelford Cams ... on a built block and GTM twins... i'll update with some feedback once the car is done this weekend hopefully.

 

im still researching the pros/cons on going 1mm over.. not too much info out here...

 

I talked to JWT about my engine build and decided to stick with the S7R instead of the C8R.

The C8R has a 272 grind and so does the BC Stage 3
The S7R has a 262 grind and the BC stage 2 has a 264

BC Stage 2 Cams

ADV.Dur.
264deg

Dur@.050
222Deg

Lift (In)
.426"

Lift (mm)
10.82


JWT S7R

Adv. Dur.
262.5deg

Dur@.050
225.5deg

Lift (In)
.450

Lift (mm)
11.43

So I used the Dyno Chart MRC posted a while back when he compared the
the BC Stage 2 and BC Stage 3 as a starting point

https://my350z.com/forum/forced-indu...ts-are-in.html

I have the Haltech so I can always make cam adjustment.

I use the grinds as a starting point in the comparison but there is a lot more to it than that.

http://ls1tech.com/forums/generation...cam-guide.html

 

Pros

about 6.5% bigger exhaust valve and about 5.5% bigger intake valve - This means the the total flow area up to the valve head is larger. Theoretically, the larger valves should flow better.


Cons

Cost

lower intake charge velocity - this means that at low - mid rpms not as much air/fuel mixture will make it into the cylinders, which means less hp in the low-mid rpm range

larger diameter valves - This means there is less clearance between the valves themselves and between the valves and cylinder walls for the intake charge to flow around. Does this overly disrupt the flow, I don't know. To really know, someone would need to flow test two heads side by side, one with stock valves installed and one with over sized valves installed. Nevertheless, I suspect that having less clearance around the valves will at least partially offset the increase in flow that would otherwise be provided by using the larger valves.

 

Nice find.

I looked at the dyno charts provide by MRC. Something does not look right. Based on the longer duration of the Stage 3 cams, you would expect the Stage 2 cams to provide better mid-rpm torque, but to drop off faster than the Stage 3 cams as the rpms climb. That dyno plot is exactly the opposite. The Stage 3 cams are building mid-rpm torque faster, then nose diving in the upper rpm range in comparison to the Stage 2's. Look at how fast the torque is falling on the Stage 3 cams after 4750 rpm, while the Stage 2's are holding on. That is not right. If memory is serving me correctly, the BC Stage 3 cams do not fall off that quick, but actually do pretty well at holding onto their torque as the rpms climb. I'm wondering if he got the traces mixed up.

If anyone has a dyno plot, or a link to one, using BC Stage 3 cams for comparison, please post it.

 

im not liking that too much.

 

From BC's Website

Stage 2


Stage 3

 

^^^^^

Notice how the Stage 3's are holding the power up to the higher rpm... That looks more like what I am used to seeing. Testing still was performed by MRC.

 

am I missing something............I thought we were discussing RevUp cams?

 

and I'm trying to show you guys how to properly choose your cams and do your homework so you can better understand the technical information provided and make a proper informed decision than just jumping on a cam because so n so recommended them.

 

I'm not sure how much weight you want to give this, but Dave from HeadGames told me that the 1mm oversized valves I had originally were shomewhat of a waste. He said he could accomplish roughly that same flow by blending the stock valves on my DE heads. HR heads already flow better fom the get go, it may be worth your time to give Dave a call and see what he thinks since he does this all day every day for individuals and race teams.

http://www.headgamesmotorworks.net/i...id=2&Itemid=57

609.882.3211 - Dave

 

^^^^

Great info!!!!

Actually, I'm sure he knows more about this than any of us, so I put a lot of weight on his opinion.