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Questions about SRT intake for GS4

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Old 08-28-06, 06:31 PM
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sbgs400
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Default Questions about SRT intake for GS4

i've read the old threads about SRT intakes and most people tend to point to the fact that the intake box is not completely enclosed as one of the reasons why you lose torque down low with these intakes. is this this the only reason or are there other reasons? i think a couple of people have built custom intake boxes that are enclosed, does the car still lose torque down low with this?

there are lots of references in old posts to wait for dyno results using the SRT intake from "the california guys", but i can't find these dyno results, were they ever posted?

thanks for any info.
Old 08-28-06, 06:48 PM
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PHML
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Do a search...i know there was a dyno done...but i think the race ecu was not installed when it was done.

Check on the SRT website...dyno results may be posted up.

Pete
Old 08-28-06, 07:06 PM
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sbgs400
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yeah i know about the dyno graph on the SRT website, but there are lots of old posts saying wait for these other dynos because they will supposedly disprove the HP gains, but i can't find any of these dyno graphs anywhere.
Old 08-28-06, 07:15 PM
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GWELEX
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I would think that for as long as the SRT intake/ECU has been available that if there were tests disproving the SRT claims they would of been posted by now. This is just a wild assumption on my part knowing the nature of car enthusiasts.
Old 08-28-06, 07:15 PM
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AZDesertGS
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I disproved it at the track....real world. Save your money. Put it towards something that will actually make your car faster....like a 3.76 LSD or a torque converter.
Old 08-28-06, 07:40 PM
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sbgs400
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hey AZDesertGS, no offense man but i read your exploits and there were too many variables there to disprove anything. something as simple as track surface conditions on different days can cause the differences you mentioned. i'm not taking a stand here for or against SRT i simply want to see some concrete evidence.

i think it's indisputable that the SRT intake looses torque down low, what i'd like to establish is why and if possible how much.
Old 08-28-06, 08:26 PM
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All I know is I got the same times in worse conditions.......So I can say that I would have had better times if there was no head wind and it was a bit cooler. People can love this SRT all they want.....but imo, it's not worth it. Especially when you can get another hot air intake for 1/2 the price and don't have to jack around with some very important wires.
Old 08-28-06, 10:48 PM
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sbgs400
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here's the part i don't understand, you replaced the SRT intake which some people have said suffers from hot air intake with another hot air intake that doesn't have an ECU correction and said you got better results. this doesn't add up (i mean intuitively it doesn't add up, i'm not saying you're exagerating or anything like that). this completely blows the theory that it's hot air causing the SRT to perform badly at low RPMs.

the only thing else i can think of is that maybe the ECU piggyback is not performing the way it should. SRT has posted a dyno chart that shows power gains, others have said they were going to post dyno charts that show the contrary but i have yet to see them.

i hope you understand i'm not trying to start a big arguement over this, i'm just trying understand what is the underlying issue here.

Last edited by sbgs400; 08-28-06 at 10:49 PM. Reason: change
Old 08-28-06, 11:44 PM
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I dont think there was a malfunction on AZdesertGS SRT intake. If the ecu piggyback was malfunctioning, I would think his car would run rough and such, but that wasn't the case. He ran better times in a hotter climate, plus on bigger/heavier rims. Perhaps the intake piping is larger than the current intake he has, thus having less low end power. due to the lower air velocity. I dont know about some people, but I rather keep my low end power since I drive around the city a lot. No need to romp my throttle to get the gains of the SRT. I've dropped money on the SRT before and sold it shortly after. just wasn't worth it to me. I should have used that money on re-piping my exhaust instead.
Old 08-29-06, 06:55 AM
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sbgs400
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hi GSteg, larger exhaust piping can cause you to loose low end torque because of loss of backpressure, but i don't see why larger intake piping would, maybe i'm missing something there. i agree that keeping the low end power is important, that's why i'm trying to find out what exactly the problem with the SRT intake is (if there actually is one).
Old 08-29-06, 07:04 AM
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It's individual taste, you'll probably find more people who will approve of the SRT (or any intake) over those who want to remain stock. There is no question that getting more air to the engine will help but whether or not its giving you the HP gains that SRT claims is debatable.

The real question is whether or not it's worth the 400+ bucks over the cheaper options and that boils down to individual choices. With the 430 there were limited options available at the time so yeah it was worth it for me. If I want to get quicker of the line then there are other choices I can use to make that back up (TC, LSD, etc). With the 400, you have choices (Injen, K&N, etc) so its up to you to decide if the cost is prohibitive.

There are few better sounds than the GS4 with aftermarket exhaust (and piping) and intake combination at WOT though.
Old 08-29-06, 08:36 AM
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Originally Posted by sbgs400
i hope you understand i'm not trying to start a big arguement over this, i'm just trying understand what is the underlying issue here.
It's cool man.....no argueing here. A lot of companies claim this and claim that with there pretty little dyno charts. Look at a lot of these exhaust manufacturers claiming 15, 20 even 25 hp gains and people have done dyno runs and track runs and have proven that its not even close. THe intake was installed 100% correctly on my end and if the piggyback was beat....I probably would have had some issues that were very noticable. Don't get me wrong...it is a nice looking and sounding intake but....for the cost and the hastle of soldering into the ecu (can be scary) and getting the same, if not worse real world results, to other intakes. The only reason I bought the Injen was I couldn't find my stock set-up.....or else that would have been put back on with a drop in filter for $40. Like mentioned in an earlier post.....I had worse conditions....heavier rims....and got the same results. I'm actually going back to the track here in the next few weeks to see about 1/4 mile differences of the 3.76 LSD and the stock diff. I just put the stock diff back on this week so we'll see
Old 08-29-06, 10:30 AM
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Originally Posted by AZDesertGS
I'm actually going back to the track here in the next few weeks to see about 1/4 mile differences of the 3.76 LSD and the stock diff. I just put the stock diff back on this week so we'll see
that should be interesting, i look forward to seeing those results.
Old 08-29-06, 09:33 PM
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Originally Posted by sbgs400
hi GSteg, larger exhaust piping can cause you to loose low end torque because of loss of backpressure, but i don't see why larger intake piping would, maybe i'm missing something there. i agree that keeping the low end power is important, that's why i'm trying to find out what exactly the problem with the SRT intake is (if there actually is one).
reducing backpressure of an exhaust is always good. You lose low end power with a bigger exhaust pipe (if your setup wasn't made for the bigger pipe) because of the decrease in velocity. It's all about the air flow in and out of the engine. If you have a larger intake pipe, most likely you'll lose low end also because the decrease in intake velocity. Performance isn't always based soley on air velocity (velocity vs. cfm), but with the SRT, the bigger intake pipe shines at higher RPM where the engine benefits from the increase air volume. At higher RPM, the engine probably sucks enough air that the velocity is acceptable.
Old 08-29-06, 09:55 PM
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yep you are absolutely correct about loss of torque in the exhaust due to decrease in velocity. i didn't realise that the SRT intake pipe was that much bigger than stock. that does shed some light on the problem.


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