what gains would i get with the ls4 and a 3" rebel intake?

 

i picked up 17hp under the curve with mine

 

You happen to have a dyno sheet you could post or pm me? Would really like to see

 

not yet should have one after thursday

 

Nobody ever making big power has needed the LS4 throttle body... Not S/C, nor custom turbo...

You may gain a little power under the curve down low, but up top end I believe I've heard it to actually lose power.

The driveability sucks. You can learn to drive around it, and get used to it, but it still isn't 'good'.

The throttle body is not a restriction... There is no need for a larger one... Nobody has ever offered proof that is it 'better'. Rebel tried to the one time years ago, and it showed about 10hp down low, but still wasn't good for the top end.

It basically opens the throttle blade 30% more over the stock LSJ TB, so just push the gas pedal more lol. High RPMs, you *aren't* maxing the airflow of the stock LSJ TB...

I drove one on the M62 and the TVS for over 2 years, and all it did was shorten 1st gear, and make the car super touchy.

Spend the money elsewhere... My $.02

 

this

 

cry me a river

 

make the power first.

 

p0w3d.

 

I Just bought a an s4 throttle body and the reason is that my thottle body sensor is going out cause my car keeps doing the engine reduce power. Anyways quick question does the ls4 tb need a adapter plater or does it just bot on. What i mean is do i nee to modify it or willl it just go on. Any help would be appreciate.

 

Murdered SS - You will need to get a tune for the throttle body and from what people say your drive ability will suffer greatly, many suggest you go back to stock.

 

it will bolt on but because it is larger you will need to either open up the blower so the throtle plate open all the way or get an adapter plate and modify your intake to fit with a coupler then you will need to rescale it in the pcm with hpt as for drivability its touchy but once you get used to it its awsome it brings in alot of bottom and midrange into the power curve

 

I have to dig up my dyno sheets, but that isnt entirely true. While i cant speak for the LS4 TB, there ARE gains to be had w/ even a slightly enlarged or ported TB. I did a before and after dyno of my SC and gains were about 5whp/3-4lbft on a stock balt (not 100% on the tq #)...across the board...not just under the curve...

And drive ability was FLAWLESS, better than stock. I didnt want to give the prototype back

 

The ~5hp/trq are normal dyno fluctuatins which could be caused by any number of things. The key word of your finding is also 'slightlty' enlarged, as that should help, but something like the LS4 is much larger and will likely hurt things. There is a point of diminishing returns.

The juice isn't worth the squeeze.

 

No, 3 runs done before, 3 runs done after, all showed 5 hp gains, so it wasnt a dyno fluctuation

but i get what your saying. Wasnt starting a pissing match, just saying there ARE dyno proven gains to be made...not with an LS4, but a properly designed one.

i wish we could have dyno'd it on a stage 2 for example...

 

I hear ya. I agree. A ported TB is almost always a decent upgrade on most every platform. From what I've experienced and seen/read on here the LS4 is kind of an overkill though. Some of the guys making big(ger) power didn't need it/want to use it/etc.

 

im just going to port mine.... better and cheaper.

 

I could see where it would have SOME gain....

You wont need to increase your intake manifold though, your SC will take care of that. A larger throttle body will just make it eayer for the SC to draw air in and pack it into the intake manifold.

But if your gona want a larger TB, then you're probably best off getting the 3" ZZP intake, as well as a SC that has a larger input side. Each of wich would help the others maximise the poltentioal gain.

 

The throttle body IS a restriction....

It allows a controlled restriction of the air going into the engine, and is used to control the engine by use of the throttle valve.

 

Hey quick question my tb sensor is messing up i have a 1s4 tb. So my question is if i swap my tb how would my car drive or will it be drive at all without getting a new tune i'm on stock tune?

 

I have not heard of this. If you can reference this, please post a link. I have a hard time believing it will rob you of top end power.

It does not open up the throttle blade 30% more. That would be impossible. If you opened up the stock one 80%, would the LS4 be opened up at 110%?

What it does do is let in about 30% more air per given throttle position. This, when matched with fuel (i.e. good tune - maf), creates more power down low. (More air plus more fuel = more power)

A quick tune is all that is needed to help relieve the "touchiness."

I would highly recommend a tune when you install it. Not only will it be very touchy, but the MAF will be skewed as well, resulting in a rich/lean condition which may even throw a check engine light.

Keep in mind that if you are on the stock M62, you will need a spacer designed for this LS4 upgrade, or you will need to grind out the inlet of the M62 in order to even have the throttle blade open. You will also need a coupler to connect the larger opening of the throttle body with your intake.

If you have an aftermarket blower (i.e. TVS), the inlet of the supercharger may be big enough already, so a spacer/modification may not be needed at all. For example, the TVS was actually designed with the larger LS4 throttle body in mind, so no spacer is needed.

 

Wow, there is a shitload of misinformation in this dead and old thread...

People should really search around and read up on stuff from 'back in the day'. Start with RAW's testing of the LS4, up until everyone who ever made big power on a blower not using the LS4... Bigger isn't always better.

But I digress, I sold my LS4 TB over a year ago, and I don't even own a Cobalt anymore...

 

Is there something that I posted that was considered misinformation? Please elaborate...

I never said that it would give you big power. Just down low power, or, like stated, "power under the curve."

 

you dont even know when back in the day was

 

Haha aight boss. I guess that's why I've moved on to bigger and better things. Just a hint, I represent the .01% demographic on here not the others...

The original question was whether or not the LS4 TB was worth it, and the short answer is 'no'. Nobody has proven otherwise, and the attempts have been just as unfounded as those that say otherwise. Now you two are some of the ones who may know what you're talking about, but unfortunately you can't speak for the others.

Like Bryan told you earlier, prove it... I'm out.