2rz/3rz OEM camshafts

12437 Views 41 Replies 14 Participants Last post by Keo, May 14, 2010

Slick Nick

Discussion Starter · Feb 21, 2010

Are 2rz and 3rz oem camshafts the same with the same specs? I searched and couldn't find any reliable info but does anyone know how many rpms the factory camshafts are good for in a boosted application? This includes upgraded springs etc.

1 - 20 of 42 Posts

Firdaddy

· #2 · Feb 21, 2010

luis at paradise has mentioned before that the stock head and block are good to around 6800 all day long, however it does not make power that high up.. the stock bottom end is very very stout for stock.. so that shoudl last just fine.. i would not take it to 9K per say however..
are you chasing more power by raising the revs? or just a more usable rpm band? honestly , i can tell you for power, its not worth the trouble of raising the rev limiter to gain a couple ponies.. however this is just my opinion...
if you really want to know , just call luis, he can tell you everything you need to know from personal experience, not internet forum hearsay

Slick Nick

Discussion Starter · #3 · Feb 21, 2010

Thanks Fir but I was just trying to figure out how high a rpm the stock cams make efficient power while being boosted until I figure out what kind of cam profile I want. I didn't like the cams that I got from LCE they moved the powerband up too high and I was gonna use the stock ones till I figure out what kind of profile I want

Speed Freek

· #4 · Feb 21, 2010

Nick, just so you know, your motor WILL NOT LAST if you spin it too fast, just boost it at the lowest RPM you can and it will live longer, I wouldnt recommend going over 7000rpms, due to longevity issues.

mitzu

· #5 · Feb 21, 2010

Nick isnt your motor completely built?

Proteus503

· #6 · Feb 21, 2010

the 2rz and 3rz camshafts are the same to the best of my knowledge.

the stock ones will make power up to about 6000 rpms... they're designed for instant torque. If you've ever seen a stock 2rz / 3rz dynograph, the torque line between 1000 and 2000 rpms will shoot straight to the top, then plateau up to redline.

If I was running stand-alone engine management and upgraded valve springs, I would definately be in the market for a different cam profile.

If i was running a boosted engine, I would beware of cam profiles with "overlap".

If the LCE cams that you're talking about are the "stage 1" cams, those are street cams, with overlap. they are not designed for a boosted engine.

Hope this helps.

McKeever

· #7 · Feb 21, 2010 (Edited by Moderator)

2

Just for a reference this is what the power band looked like when I did a 3rd gear pull on a chassis dyno with stock cams, 7psi, s256 with a .55 a/r hot side, and open exhaust.

See less See more

jakew88

· #8 · Feb 21, 2010

I'm pretty sure the entire head is the same. Distributer heads and all. Just a hole put in the head. As far as my dad says at least. I hope he's right. Lol.

mitzu

· #9 · Feb 22, 2010

Luis said in a post before that his racecar improved alot with cams...he said he was making more power with less boost and nos when he put cams in.

planemos

· #10 · Feb 22, 2010

You shouldn't have to change the stock cams to turbo a 2RZ. Unless you are planning to challenge Paradise Racing.

Slick Nick

Discussion Starter · #11 · Feb 22, 2010

Speed Freek said:
Nick, just so you know, your motor WILL NOT LAST if you spin it too fast, just boost it at the lowest RPM you can and it will live longer, I wouldnt recommend going over 7000rpms, due to longevity issues.

I realize that and thats why i want a different cam profile. I dont wanna drive around a honda civic that revs to the moon, its a truck for gods sake. I want some power down low too. Thats why I was going to use the stock cams until I found a boosted cam profile that was made more for OUR engines normal operating rpms and not that of a Honda. Ya know what i mean?

Proteus503 said:
the 2rz and 3rz camshafts are the same to the best of my knowledge.

the stock ones will make power up to about 6000 rpms... they're designed for instant torque. If you've ever seen a stock 2rz / 3rz dynograph, the torque line between 1000 and 2000 rpms will shoot straight to the top, then plateau up to redline.

If I was running stand-alone engine management and upgraded valve springs, I would definately be in the market for a different cam profile.

If i was running a boosted engine, I would beware of cam profiles with "overlap".

If the LCE cams that you're talking about are the "stage 1" cams, those are street cams, with overlap. they are not designed for a boosted engine.

Hope this helps.

The cams that i have right now are the stage 2 cams which are made for boosted engines. From what LCE told me their powerband is from 4.5k-7.5k which is a little too high for my taste. I dont want a strictly drag race truck, I want a powerband that is more streetable.

Slick Nick

Discussion Starter · #12 · Feb 22, 2010

McKeever said:
Just for a reference this is what the power band looked like when I did a 3rd gear pull on a chassis dyno with stock cams, 7psi, s256 with a .55 a/r hot side, and open exhaust.

Thanks for the input. So what im getting from the graph is that even boosted the cams make the engine drop off after 6k rpms... good to know.

Slick Nick

Discussion Starter · #13 · Feb 22, 2010

mitzu said:
Nick isnt your motor completely built?

Ya it was and I was very unhappy with the way it turned out. Since it was damaged a while ago I got another block and I'm starting over, changing a few things this time around.

planemos

· #14 · Feb 22, 2010

What kind of a curve are you aiming for then Slick Nick? I ask because it sounds like you have a nice setup already.

Slick Nick

Discussion Starter · #15 · Feb 22, 2010

planemos said:
What kind of a curve are you aiming for then Slick Nick? I ask because it sounds like you have a nice setup already.

For the reason of turbo size I don't really wanna rev higher than 6500 rpms. The turbo I plan on using won't make full boost until around 4k rpms and probably start making it around 2500 rpms so I want the motor to be reasonable until then with useable torque that I can use when I'm outta boost and just cruisin.

Speed Freek

· #16 · Feb 23, 2010

As far as your truck goes I bet you would make more power with the stock cams when boosted than your current cams..

What is the boost level or horsepower you have in mind?

siggie30

· #17 · Feb 23, 2010

Looking at that graph tells me that if you unshroud the exhaust valves, you will level out the torque band a bit in the 3500 area. I wouldn't consider opening up the intake, as the whole graph will make a rather unfortunate slope for a truck. Just my .02 A little less overlap on your new cams will also increase your torque, and since your boosted the upper end is not really an issue.

Slick Nick

Discussion Starter · #18 · Feb 23, 2010

Speed Freek said:
As far as your truck goes I bet you would make more power with the stock cams when boosted than your current cams..

What is the boost level or horsepower you have in mind?

Whatever I can make on 91 octane :evil:... the fuel is the limit

The current cams I have, are made for boosted applications and have very little overlap...they are meant mainly for drag racing.

Speed Freek

· #19 · Feb 23, 2010

Slick Nick said:
Whatever I can make on 91 octane :evil:... the fuel is the limit

The current cams I have, are made for boosted applications and have very little overlap...they are meant mainly for drag racing.

Oh thought they were stage II cams for N/A, didnt know they were setup for aspiration.

Slick Nick

Discussion Starter · #20 · Feb 23, 2010

Speed Freek said:
Oh thought they were stage II cams for N/A, didnt know they were setup for aspiration.

That's what I thought too when I first bought them, then when I discovered that I wasn't making very good power, I researched the cams cuz I thought I had them degreed wrong. That's when I found out that they were designed for high rpm boosted applications.

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