Here's a few interesting threads. Redgs4 has had both the K & N and SRT . We dynoed the K & N so it will be the SRT 's turn next time.


https://www.clublexus.com/forums/sho...rt+dyno+intake

https://www.clublexus.com/forums/sho...ght=srt+intake

https://www.clublexus.com/forums/sho...ght=srt+intake

 

Glenn et al,

That dyno event was very poorly done, especially the SRT intake test. It was dynod without the ECU which should never have happened. The SRT intake isn't ever meant to be used without the SRT ECU.

EDIT you guys already have that covered above

Toss that entire test out IMO. Looking forward to your new one

 

I checked for an injen intake on injen's website and it show that for the gs400 its discontinued?? I am so confused bout which intake to buy. I got to wait for a solid thread, with solid numbers. I think that someone should compile the threads into one and make it a sticky. Because this is like hunting for a needle in a haystack.

 

Yeah Injen doesn't make it for our cars anymore. As far as the SRT intake is concerned, the only one that has done a true before and after test on the intake w/ ECU is SRT themselves. Independent testing would be more conclusive.
Just my 25 cents.

 

i don't know.. i never liked weapon - r and injen is good but since SRT is specifically designed for our cars and they have an ECU, that's the reason i went with them.. to me, it's a great mod, great sound, great added performance, i just love it in general, i'd definately recommend it, but another dyno of all the intakes would be awesome just for comparitive purposes

 

tell you the truth I like the fact that it comes with an ecu but what if it wasn't needed? Looks arent everything. I would like to get an intake for the wow factor but also for a lil horsepower. Now if the SRT gives more horsepower than it would in fact be worth the almost $400 price tag but if the weapon-r does the same for a cheaper price, what's the point?

 

I recall gathering several dyno-related thread links for the SRT intake/ecu - at least two of them had a before / after I think.... Link to thread
https://www.clublexus.com/forums/sho...d.php?t=151714

 

Dave workin his magic again. Well it seems the SRT does add about 20 plus horses to the wheels. Ok guys buy em while their hot.

 

Lol, thanks.

I would caveat that the gain varies from car to car, just like some GSs are faster than others (and even dyno 10 - 15hp different) from the factory for the same year.

 

Forget weapon R - The company lost it's rep a long time ago.

Injen - Well they bailed on us too bad.



The only other intake I would consider is the K & N. It has a smaller intake pipe than the SRT, but larger than stock and potentially better flow with the removal of the muffler portion in the stock set up.

The SRT has a large intake pipe much larger than what the car was designed for. Which means it MUST have an ECU to manage it.

The reasonable intake pipe size of the K & N means the factory ECU can "tune" itself to the intake to some extent. It is still in range of what the ECU can compensate so ECU not required.

So does bigger mean better? Only if you want to trade off some low end power for high end, which is what the SRT does.

The report of the SRT doing 20+ HP is a notable improvement, but at a much higher cost. The K & N may yield less power, but the cost is also quite reasonable.

The K & N Sounds great, doesn't have the loud hissing as the SRT which is not an impressive sound IMO. The K & N will be relatively quiet at idle and normal driving , but really opens up nicely when you jump on it.


The K & N does not requre an ECU, but if you add a APEXi and a little tuning you'll have essentially a similar set up to the SRT and possibly better. See Bitkahuna's post for results of tweeking the K & N with an APEXi. It bumped the performance of the K & N up another 4 HP, but as he notes, the torque increase was even more noteable.

https://www.clublexus.com/forums/sho...ighlight=apexi


In terms of which is better, the key comparisons I'm looking at is HP per dollar.
Powerband in the lower / mid range.
Great sound when at wide open throttle.

I'm leaning towards the K & N in all of the above categories.

Hopefully we will be able to dyno redgs4's car with the SRT in the next few months and compare it to his K & N readings. We'll have to sync this activity up with dynoing before / after S & S header installs on three of our local cars as well.

It would be great if the K & N put's out some decent power w/o ECU and then people could have the option to upgrade further with the APEXi as their budget allows.

Hopefully we'll have more conclusive data in the near future.

 

Very good point Dave.

This is why we are dynoing the same car with both intakes and will try to stalize all other variables so that we can have the best shot at knowing what the true power gain was.

 

I don't believe K&N makes an intake for the 430's.

 

Yep that's great! What would be even better is to do the same thing with two (or more) cars because it seems many cars respond to mods differently for some reason (even with similar baselines). But know that's an ideal world scenario and costs a lot more in time and $$$ that isn't practical.

Please be sure to note down the temperature and humidity during both runs, hopefully will get same dyno and dyno operator as well as similar condition of the car (motor cooled after drive in, ECU just reset, etc)

 

We ran the K&N first, then swapped back to the stock intake (and reset the ECU) while another car dynoed, then ran again stock. While this controlled the environmental variables of temp and humidity it did not give the ECU much of a chance to "learn". Only other HP mod is a Tanabe Hyper Medallion exhaust. The horsepower and torque curves are consistent between both with the K&N always a bit higher.

K&N - HP Max: 242, TQ Max: 255
Stock - HP Max: 237, TQ Max: 242

 

Just 5 horses with the K&N intake? That is disappointing.