What kind of power gains do aftermarket cams provide?

Depends on the car

Literally zero other than weight reduction. If you want to gain power then adjust your valve timing.

>>15656483
>Literally zero
You are some kind of stupid

>>15656475
Less power actually. People do it for sound

>cam LS V8
>huge gains 30hp+ at top end

>>15656481
and the cams

>>15656510
Yea, that too

>>15656475

They change lift and duration.

>>15656483
Wrong, but the gains are minimal without supporting mods

>>15656496
lol no

>>15656475
Cams don't add power on their own, but with a few other mods, they'll let your engine rev much higher than it would have been able to

>>15656496
What the hell are you taking about. I guess my Dino post cam lies then.

>>15656481
OP's pic is the Piper cams Mountune sells

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>>15656483
>adjust your valve timing
>but cams do that!!!
ahahahahahahahaha good one sir

>>15656744
I don't think pic was related boss

the shitty idle that you get with aftermarket cams really makes me question how worth it they are

>>15656483
>>15656496
>>15656628

/o/ is home to a special kind of stupid

>>15656788
The idle and driveability issues are due to how radical the cam profile is. You can go with something more on the mild side, retain good driveability and still pick up a decent amount of power.

How good your tune you have will also make a big difference.

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>>15656475
It really depends on the cams and engine. V8's can gain 20-50 hp.

>>15656475

What kind of supporting mods do you have? What kind of lift is the cam going to have alongside duration?

Gotta factor in drivability too. Big thumpy cams make big power with just some bolt ons and ported heads but are miserable to drive for the most part. You can go with lower lift, keeping your car easy to DD with the same mods and you'll see very respectable gains.

I know LS3 cams can get you anywhere from 440 RWHP to roughly 500 RWHP with the right supporting mods, it just depends on what you want. Also those cars make roughly ~380 to the wheel stock so very nice gains

>>15656475
In language /o/ will understand: the original V-TEC had two cam profiles, one optimized for low-RPMs and another optimized for high-RPMs. An aftermarket cam is like switching cam profiles in V-TEC, but running in that cam profile for all RPMs. You can improve power over part of the RPM range, at the expense of other parts of the RPM range.

>>15656481
really, it depends on the engine and the cams themselves

>>15656885
doesn't V-TEC just advance or retard the cam?

>>15656904
VTEC doesn't retard the cams, it changes the profile to a more aggressive one when the oil level reaches the solenoid, typically around 5.5k rpm

>>15656475
6.2hp at 7500rpm.

>>15656904
VTEC is variable valve lift. Literally like swapping in a different cam.

>>15656475
I might as well provide a solid answer for OP.
If you buy aftermarket camshafts with a higher duration and lift, you can get more power in the higher RPM's, and itll increase torque at the expense of having a higher peak torque and idle.

Thats just really a summary, but if you want to get into it, cam profile is also alongside lift and duration. If you want to make even more power at the cost of daily-drivability, get a solid roller camshaft.

Is it possible to upgrade the cam without having that god awful plinko exhaust note that comes with it?
I'm all for big obnoxious sounding v8's but hot cam sound like shit.

>>15657166

Blower cams

Not gonna get much HP increase, around 20-30 but it won't thump the ground at idle

>>15657166
If it doesn't sound like popcorn popping you're doing it wrong. https://youtu.be/Fe0iDZ24ZbI

>>15656475
Just download a VTEC

>>15657282
love that hot rod idle lope

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>>15657652
We put an insane amount of work into that thing. By the time it was done I think it was probably over 200hp n/a

>>15657621
you wouldn't download a turbo

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>>15657671

how much horsepower could I max out on my lawnmower with a cam, and nos

>>15656506
>V8
>30hp only at top end

nice

>>15656628
spotted the forza nerd

>>15657282
nice vertical video you retarded fuck

>what do cams do
Man sometimes it's astounding how much /o/ doesn't wrench

>>15658223
that is a ton for just a cam swap


>not including head work, exhaust

400+ hp N/A LS1 is easily possible

>>15656885
So does Vanos. Well, without having two separate profiles.

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>>15656475

>>15658890
That only adjusts camshaft timing, not lift and duration.

>>15658930
Yeah, but you should always be running maximum lift anyway.

>>15658930
Huh. I thought it lifts, too.

>>15658935
Why?

>>15658966
He doesn't know anything.

>>15658696
At least OP is asking an honest question. It's the responses that concern me. See >>15658223 (benchracer detected).

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>>15656885
ayee
>>15656904
Variable Valve Timing and Lift Electronic Control ???
>>15658935
some people do but that is only for track cars

popping cams in will do very little on it's own. Changing lift and duration will lower cylinder pressure during hella comp overlap. Raise the compression ratio and notch those pistons.

>>15659039
how do they get the rod in there when your engine is going a million rpms a minute

I gained 32whp at 3100rpm with the VERY mild cam I got for my PA

>>15662122
>rpms a minute
Guess how I know you're a retard.

>>15662138
just answer the question nerd

What gains do cams usually get on DOHC 4-bangers? Talking about mild/moderate upgrades you can still daily, not race cams and shit

>>15662163
depends on the car and cam you fucking arsehole read the damn thread

>>15662163
Bout tree fiddy

>>15656475
depends on the car

i6 and v8 can see massive gains all over the mid-high range but i4 is mainly just high end gains.

Havent put one in any of my engines yet but soon.

Generally though yeah my ls would go from 310hp at peak to around 400+ with heads

>>15662122
please respond im actually serious

>>15662879
Also curious

>>15656475
The kind that make your car go go 'potato potato potato SCREEEEEACHWAAAAAAAAAH SCREEACHWAAAAAAAAAAAAAAAH SCHRWAAAAAAAAAAAAAAAAAAAAAAAAAAAAH'

You buy the cam first and build the engine around it if you want to do it correctly, work out where you need power for your application and buy that cam for the motor you want.

>>15662909
>he doesn't design his own cams

>>15662917

Why? When there are a thousand cams out there for every car for every application? Someone smarter than you or me has already put in the time and effort into making sure that Cam A does Application X perfectly

>>15658192
Fuel?

>>15662945
either the cam you can buy off the shelf is automatically perfect or you need to build your engine around it
you can't have it both ways

>>15662988

That's why you build a engine around a cam, not buy a cam to try and fit the motor

>>15662996
you're not making any sense lad

>>15658935
No you shouldn't you dumb cunt.blower lift equals higher gas velocity at lower engine speeds, which means better cylinder fill. Also, BMWs valvetronic controls lift.

>>15663059
Makes perfect sense.

Any system without variable duration/lift cams is compromising on something.

Low lift, low duration cams will flow air more efficiently at low RPMS, therefore are bad at high RPMS, but good for torque.

High lift, high duration cams, compromise low end torque, but flow more efficiently in the high RPMs, which produces horsepower.

VTEC, has two lobes that, that give two cam profiles, one more low end torque, and one more high end power.

Newer "Variable" systems do the same for ignition. Ignition is retarded, and advanced from low to high.

Even the same with cam positions. They retard, and advance through the rpm range to create efficiency.

You can tell when a motor is running at peak air flow efficiency because a motor will have peak torque through the whole power band. That is when flow is perfect.

It's why the introduction of new systems are being created. Like Pneumatic valve systems, that are complete variable, lift and duration, through the whole RPM range of the motor. They're also creating ones with solenoids.

https://www.youtube.com/watch?v=ppKy6Qp5pLU

It's why you build a engine around a cam, or the application. Big stroke engines don't rev as high, or as freely, so a smaller cam fits big torque motors, but you can have really long gears, as you have more torque. Meanwhile big bore, low stroke motors(Motorcycles, b18s, f20c, 4age) usually rev higher, and make horsepower, not torque, thus have shorter geared gearboxes so you can stay in the revs.

You design your engine around the cam, then design your gearbox around the motor.

>>15663169
>typing all that out just to be wrong
lmao

How about an amc 4.0 i6?

>>15662879
>>15662890
I'm not positive but I think the pins are pneumatically actuated.

>>15658961
We adjust lift through a thing called Valvetronic. Its literally a little motor that spins to decrease or increase valve lift based on how tightly it sets a spring in the head (BMW tech)

>>15663278
>pneumatic
That means using pressurized air. The locking pins are simply hydraulic.

>>15663304
I see, I must have been confusing it with Koenigseggs free valve tech despite vtak being far superior valve technology. How does vvt-i work?

>>15663304
>>15663278
What I'm wondering is how does the pin get through the hole while that shit is moving up and down at such a high rate of speed and not accidentally go over or under the rocker arm

>>15663169
>VTEC, has two lobes that, that give two cam profiles, one more low end torque, and one more high end power.
Ever notice how no 2-lobe VTEC engines have good low end torque? Because the compromise you speak of isn't just a cam thing. VTEC engines need short intake runners and big ports to achieve the on-cam HP numbers, so they are already compromized for the high end. The low camshaft profile cannot change that; a cam profile alone cannot increase runner velocity or take advantage of a low RPM resonance charge effect or increase the velocity in large ports. That's exactly why Honda VTEC engines are not, and never will be torquey engines.

I'm sad to say, but camshaft profiles alone, especially 2 distinct ones, can't ideally optimize an engine for both low and high RPMs. Like you say, the engine has to support the cam and until Honda invents continuously variable port volume and variable runner diameter and length, VTEC engines too will be a compromise like every other engine.

>>15663347
the oil solenoid opens and the oil pressure presses the pin up against the rocker arm until the hole passes the pin then it locks in. the rocker arm is only going up and down about an inch or less

>>15663362
If it's pinned against it while it moves then there's at least microscopic grinding or wear as it "waits" to shoot into the hole, right?

>>15663349
the ports and valves are too big even for the high lift cam
and the valve inclination is pretty daft
would have been nice to have seen them fix that but it's just turbo shit now

>>15663374
sure, for a 1/500th of a second probably

>>15663388
>would have been nice to have seen them fix that but it's just turbo shit now
Yeah it's weird they caved in and are doing what everyone else is doing. The VTEC patent [locking rocker arm] is expired by now. Anyone can do it but the automotive landscape is so different than it was 25years ago

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>>15663349
>this whole post

This is the most vague thread on /o/ that's lasted this long, there is no one answer because no two engine profiles are the exact same. It will vary wildly engine to engine.
/thread

>>15663414
>The VTEC patent [locking rocker arm] is expired by now. Anyone can do it
Oh wow i didn't know that. I wonder if anyone will use the design.

>>15663460
Delphi (GM) has literature about their version, it's up for grabs for a while but since it's not a solution for the current challenges like emissions, CO2 and Fuel Economy no one seems intersted

>>15663298
You are a hopeless BMW tech. The valvetronic motor controls an eccentric shaft which alters the amount of lift provided by effectively changing the rocker ratio.

>>15663460
Noone uses it as everyone has better designs that allow for completely variable lift and timing. VTEC is a crude as fuck way of doing it.

>>15663581
>VTEC is a crude as fuck way of doing it.
Crude maybe, but can't deny simple and reliable.

>>15663581
Valvematic a best but I thought some second tier manufacturer would pick it up. A Lada Niva with VTAK would be pretty sick

>>15663587
And it makes for exciting engines imo.

>>15663587
Yeah its reliable but it doesn't give the economy and efficiency that manufacturers want now.

>>15663642
>And it makes for exciting engines imo.
Tbqh I've driven most Hondas apart from the nsx and I wouldn't say the engine were exciting. At least the s2000 revs like fuck I suppose.

>>15663460
>>15663581
Yeah they have i-VTEC now which is a completely different system. https://www.youtube.com/watch?v=UEtm2y1yXnI

>>15664219
No, it's just VTEC with variable cam timing added.

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This may be a dumb question, but what are the downsides of a cam? Do they decrease engine durability or reliability?

>>15664243
Except you know the fact it can modulate both intake valves independently.

>>15664564
They just shift peak torque to a different spot in the powerband. Usually compromising low-end torque for later torque in the powerband, resulting, in much more horsepower later

>>15664243
And you know, the biggest addition. The ability to control each intake valve independently.

>>15664564
Cams just shift peak torque throughout the powerband.

>>15664564
The alternative is a rotary.

So I guess cams add moving parts which is a downside, but they allow more control over intake/exhaust so they have more performance/economy options. Also don't burn as much oil.

>>15664612
Or a two stroke. Same kinda comparison still I guess.

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>>15662122
the rod is inserted on the down stroke
while their is less load on the rocker arm and everything attached to it
as for how its timed this can be done with the crank or cam position sensor

iirc the motor oil being used as hydraulic fluid is held back by a solenoid on the basis of rpm and oil pressure
a number of redundant sensors are used
and it's not really worth getting into the detail as to how exact implementation varies while the overall principle does not

Depends if you want to pass emissions. Aftermarket cams change lift and profile. On my 600rr bike, Webb cams increase lift duration and actually increase lost air during compression, helping more on the high end than the low end.

It all depends what you want, how much money you want to spend, and what your application is.