pchio

iTrader: (11)

Hi everyone, I am at a point that my cams need to be upgraded. My car is mainly for road course only and did a few time attack events. However, sometime I did drive the car to the race track instead of tow.


My goal is hoping to squeeze out a little more power after raising up the rev limit to around 7200-7500 rpm. I currently have 4.1 Final gear and it is running out of rev many times before the turns.


My question is, how to benefit from more aggressive NA cams such as

- Brian Crower 272 / 11.6
- Kelford 271 / 11
- JWT C8 272 / 12.01
- JWT C2 261 / 11.58

on a VQ35DE non-rev?


Rod bolts and oil pump will be upgraded, so raising rev limit will be fine. However, does stock internal with plenum spacer can be benefit from these cams? without touching the internal.


The reason that I am hesitating to go all out on the motor is because at the current stage, I am already in a run group that against M3, Porsche, Elise at my local time trial. I am not quite sure if I should spend that much money for just a NA build up, but at this point. I will try changing cams first. Thanks in advance, any info will be appreciated.

the_coupe

iTrader: (4)

i'll be selling my port matched and resurfaced heads with stock valves and BC 264 cams/valve springs/ti retainers. pm me if thats something you'd be interested in.

Classy

iTrader: (7)

To be honest, for a non-rev, it is REALLY hard to push past 7k rpm making power. My dyno sheet shows me running out of power at about 6800, BUT I don't lose many HP to my 7k red line, I am currently running JWT C8's

To be honest, I doubt I made 1 hp from the internals... I really don't see you having a problem running bigger cams on stock internals.

Something I will say, my C8's suck in low RPM, but scream at mid and up top. Just alittle FYI

the_coupe

iTrader: (4)

QFT...unless you have some sg headers and a massive flowing intake you might gain some top end....but it is hard on a nonrev.

i can say that i am/was impressed with my build and how it ran throughout the range.

pchio

iTrader: (11)

Thanks Guys! I think as long as it stays around the peak power and does not drop sharply after 6.6k rpm, that should be good for me for now.

That's exactly what I am thinking too. And I searched and found your post. So the 292HP dyno graph was with C8 cams and built internal. The Curve looks really nice. Any mods on intake maniford and the heads too?

I have seen Fontana and SG Z, and I totally agree with u. Do you have a rev up or non rev?

350Zdj

iTrader: (3)

I got JWT C2 cams on my car and installed the JWT heavy duty springs as well. It shot up my rev limit to 7k automatically. (My engine is the non rev up VQ)

Performancewise there is a lag on lower RPM but pulls better after around 3.5k all the way to redline. No dyno proof yet but I can tell there's a difference as i DD my Z. I've still yet to tune the car to get the most out of it. Rev on idle is fine.

mw9

iTrader: (51)

In for suggestions, I am getting to this stage where a cam is next

Z1 Performance

iTrader: (564)

only 1 of your chocies there will work with stock pistons

header + intake manifold + cam go hand in hand in hand, so they need to compliment one another, otherwise it becomes sort of a useless modification

Z1 Performance

iTrader: (564)

you're not supposed to make power from your internals unless you bore/stroke it - they are the foundation of the platform. The Power of the engine is twofold - it's made in the heads (everything inside, and bolted to them), and supported by the rpm's the bottom end can sustain

350Zdj

iTrader: (3)

Ok, so we have Cams, intake, headers, exhaust-
In addition to the plenum spacers, have you guys tried using the RevUp plenum into the DE manifold and did you get any positive result?

Z1 Performance

iTrader: (564)

a revup collector will increase a bit of top end at the expense of mid/low end on a non revup DE - personally I don't see it as worthwhile at all, the non revup is more than sufficient (I used a ported non revup on my own car for several years)

mw9

iTrader: (51)

which do you recommend with stock pistons

pchio

iTrader: (11)

I am guessing Adam is saying the JWT C2 that will work in stock internal since it is a less aggressive one. I talked to BC and they told me that their 272 cams requires 12+ :1 compression t be beneficial @.@

I dont mind sacrificing the low end since my car is mainly for track. I have been reading lots of those long *** NA posts and I am getting dizzy. LOL. But still cant find the answer I am looking for yet. It seems like this would be some kind of test and trial to use these cams on stock internal.

By the way, is SG still going to do another test for Modified Magazine on some aggressive cams as they speak a while ago? I have been waiting

Classy

iTrader: (7)

they did one about this time last year, if that is the one you are talking about.

To be honest, I think some 260-264 cams would be right for you. I am running 11:1 compression and I am not sure I am running all of my JWT C8 (272). I am pretty sure that they are about 90% of why I gained 30hp from my motor build

Z1 Performance

iTrader: (564)

I'd highly suggest picking up a book about engine dynamics, and reading up on how cams interact with the other aspects of the engine. It should help you really narrow your choices and hone in on what is/is not important.

You don't pick a cam by advertised duration - it really means next to nothing. There are countless examples out there that prove this. You can easily have a 260 degree cam that SMOKES one with a 272 duration.

Neither of the JWT cams you've posted will work with stock pistons.

Which would I suggest for stock, non revup pistons? Tough choice - here's why. Power on these engines is made 1 of 2 ways. Rev it (and have the parts to support those rpm's), or stroke it. Anything short of that, and you're wasting your time (IMHO). So it comes down to cams that are going to maximize the mid range because that's really all you have to work with. Which the correct choice is, again, depends on your intake manifold choice (in this case, a simple spacer will be just fine, nothing else needed and nothing exotic is required), and your header choice will mean everything.

'Aggressive' cams, however you choose to describe aggressive, are not at all what you should be looking at, because you've got nothing to support their use

Z1 Performance

iTrader: (564)

Those cams should be netting you a considerable amount more than what you've got - your headers are your main issue, and are ultimately choking where those cams would be happiest. This is most of the reason why your car is running out of steam so early in the rpm range

KA24DE

The problem is that worthless peice of metal called an intake manifold. I'll say it again (only for it to fall on deaf ears) Work on the intake manifold and cams (non rev cams are weak) That is where you will find most of the power.


All these guys do is try to band-aid the orignal issue, and sped 6K for 15 whp.

pchio

iTrader: (11)

I wish there is a "Like" button that I can click on your posts. Thanks for all the inputs.

Even the C2? I have actually talked to JWT and they told me that it will works will stock internal and C2 is a better choice for my goal. Do you mind explaining why it doesnt work with stock piston?

Sounds quite extreme, but that's what I have been thinking before the build.

Z1 Performance

iTrader: (564)

Much like a header, it's a compromise of design vs packaging. The ideal setup wouldn't likely fit a stock hood, or a stock radiator support, or use a bolt on intake, etc. etc. But, no one here has the money to invest in reinventing the manifold and all that goes along with it, so you're left to basically try to tackle the biggest weak point (volume) and go from there. Yes, the turn from the throttle body to the manifold is a weak spot...a major one. But fixing it is time consuming, expensive, and alters every single other aspect of the setup, so it's not easily achievable. One can fairly easily achieve 80+ whp vs a bone stock car using the stock intake plenum setup if the rest of the items are careful chosen

Z1 Performance

iTrader: (564)

All my notes show max lift on a stock piston is 11.3mm and that even is not leaving much margin for error