Questions about SRT intake for GS4
12-05-06, 11:58 PM
#47
the torque converter will give you that launch you're been missing all along.
Some people have lost low end power with the SRT so I doubt you'll want to go with that route. LSD will help get traction to the ground, but most people here use the Supra differential because of its 3.76 gear with LSD. This new gear ratio helps acceleration from a dead stop all the way until redline.
Some people have lost low end power with the SRT so I doubt you'll want to go with that route. LSD will help get traction to the ground, but most people here use the Supra differential because of its 3.76 gear with LSD. This new gear ratio helps acceleration from a dead stop all the way until redline.
12-06-06, 05:02 PM
#48
Nanotech, the answer is 100% the Torque convertor.
I have the headers, TC and Supra 3.76 and I've tested each one at the track for several runs, tracking air condition the entire way. Not to mention, aside from the Lexus, I have a few hundred runs down the quarter mile, recording every run.
That TC will get you about 4-5 tenths in a full quarter mile, and about 2 -2.5 tenths in your 60 foot times. Very noticeable.
The 3.76 doesn't compare when you put a stopwatch to it, vise a seat of the pants evaluation.
I have the headers, TC and Supra 3.76 and I've tested each one at the track for several runs, tracking air condition the entire way. Not to mention, aside from the Lexus, I have a few hundred runs down the quarter mile, recording every run.
That TC will get you about 4-5 tenths in a full quarter mile, and about 2 -2.5 tenths in your 60 foot times. Very noticeable.
The 3.76 doesn't compare when you put a stopwatch to it, vise a seat of the pants evaluation.
12-06-06, 06:45 PM
#51
As for the install I have no idea. I do know it's a big job though, you have to drop the tranny. I was told and quoted $600 just for the install. Go with Lextreme: www.lextreme.com .
Last edited by Lexizm; 12-06-06 at 06:54 PM.
07-07-07, 12:41 PM
#52
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This is a very interesting thread, so I thought I'd kick over this ant hill one more time. After checking out the SRT intake for the GS I was thinking that unless the SRT unit was able to draw a reliable supply of air from outside that the performance gain wouldn't be consistant. Putting the car on a dyno with a giant fan to feed fresh air likely is different than running the car on the street & hwy with the hood closed. I'm an old GTO guy, so I'm thinking why can't someone come out with a true Ram Air setup for the GS? Seems like a filter could be located somewhere in the lower bumper, and the pipe diameter could be dialed in, along with an appropriate ECU upgrade.
07-08-07, 08:53 AM
#53
Guys, unless you actually know for sure, throwing out doubts and hypothesis does nothing for others.
I installed the SRT 3 times from the GS4 to the SC430. The thing does work and works well. I have had over 10 runs between myself and another GS4 w/o the unit and each and every time I pulled on him from the dig straight through the gears as well as the highway. When he installed his SRT we were dead even.
Also, you CAN install the SRT incorrectly and NOT get a check engine light. I installed the unit 3 different ways to retrieve different signals for testing (no you will not blow up you motor) and at no time did the check engine light come on but the performance difference was noticed.
I also had a defective ECU on one of the them and again-no check engine light even though SRT said a defective ECU will always set it off. Not true.
Weather conditions will always have a say so in performance but again how many dyno shops have you guys encountered with air conditioned shops? Shops are always hotter inside vs the fresh air OUTSIDE. There may be a fan but moving down the highway is going to get you fresher and colder air than a dyno room and a fan will. If you have not had a car on a dyno-again-your posting from no knowledge whatsoever.
I installed the SRT 3 times from the GS4 to the SC430. The thing does work and works well. I have had over 10 runs between myself and another GS4 w/o the unit and each and every time I pulled on him from the dig straight through the gears as well as the highway. When he installed his SRT we were dead even.
Also, you CAN install the SRT incorrectly and NOT get a check engine light. I installed the unit 3 different ways to retrieve different signals for testing (no you will not blow up you motor) and at no time did the check engine light come on but the performance difference was noticed.
I also had a defective ECU on one of the them and again-no check engine light even though SRT said a defective ECU will always set it off. Not true.
Weather conditions will always have a say so in performance but again how many dyno shops have you guys encountered with air conditioned shops? Shops are always hotter inside vs the fresh air OUTSIDE. There may be a fan but moving down the highway is going to get you fresher and colder air than a dyno room and a fan will. If you have not had a car on a dyno-again-your posting from no knowledge whatsoever.
07-08-07, 01:49 PM
#54
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Pearlpower, I'm definately inclined to drink the Kool Aid on this one, given my experience with simply changing to a replacement K&N filter using the stock box. It did wake up the car. All things being equal, a big conical filter and ECU upgrade likely boosts the power. I guess what impresses me about this thread having read it from its start is how much passion there is on both sides of the question.
07-08-07, 02:11 PM
#55
On my GS4 I have used a the SRT (most power), Weapon R (poor quality but has since been revamped), generic Ebay unit (worked like the other non-SRT units), and K&N (ok but not great.). I have heard from others that the unit from RMM loses some power throughout the range but I cannot say as I have not used that unit. Almost all intakes will cause a loss at the low end with gains up top so one has to weight the cons and pros of this towards their driving style.
On the issue with headers, one will lose low end even further with the available header system on the market but the mid range and top end more than makes up for this loss-dyno proven a while back on my SC.
On the issue with headers, one will lose low end even further with the available header system on the market but the mid range and top end more than makes up for this loss-dyno proven a while back on my SC.
Last edited by Pearlpower; 07-08-07 at 02:21 PM.
07-08-07, 02:51 PM
#56
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On my GS4 I have used a the SRT (most power), Weapon R (poor quality but has since been revamped), generic Ebay unit (worked like the other non-SRT units), and K&N (ok but not great.). I have heard from others that the unit from RMM loses some power throughout the range but I cannot say as I have not used that unit. Almost all intakes will cause a loss at the low end with gains up top so one has to weight the cons and pros of this towards their driving style.
On the issue with headers, one will lose low end even further with the available header system on the market but the mid range and top end more than makes up for this loss-dyno proven a while back on my SC.
On the issue with headers, one will lose low end even further with the available header system on the market but the mid range and top end more than makes up for this loss-dyno proven a while back on my SC.
Your dyno shows a LARGE mid range torque gain so when you say low end please define.
On the intakes there is more to the story here. Stock has a helmholz resonator that appears to enhance low speed performance. All aftermarket systems remove this resonator (larg triagular box bolted to driver cam covers)
Peter Scott of Planet Soarer tried a number of different intakes all loosing performance until he created the BFI that gave the best performance.
I suggest that it is the air meter than may be the biggest restriction. The SRT increases the size of the meter therefore reducing its restriction. The ECU is needed to adjust for the changes in the measured flow. The rest of the system may not be a restriction. It would be interesting to test just the SRT meter and ECU mated to a stock system with an optimized air filter housing.
07-08-07, 03:04 PM
#57
Actually that large triangular item is claimed to be for air enhancement but actually is for noise reduction(baffle)/air flow enhancement.
Also I ran the SRT ECU with my Injen intake with very poor results-thread on it in the SC area.
Yes the headers are one of the best performance bang for buck out there (if not for install) but the low end seemed to suffer a bit-but only a bit and picks up from there. This coupled with an CAI and a freer flowing exhaust hurt things a bit on the low end but my TC and gears made up for it so I have the best of both worlds.
Also I ran the SRT ECU with my Injen intake with very poor results-thread on it in the SC area.
Yes the headers are one of the best performance bang for buck out there (if not for install) but the low end seemed to suffer a bit-but only a bit and picks up from there. This coupled with an CAI and a freer flowing exhaust hurt things a bit on the low end but my TC and gears made up for it so I have the best of both worlds.
07-08-07, 04:18 PM
#58
hey Pearlpower, how did you know you had a defective SRT ecu? I am wondering because on my vehicle there is this misfire at a certain rpm. Could mine be defective? I called them and they didn't know what i was talking about.
Thanks in advance for the reply.
Thanks in advance for the reply.
07-08-07, 07:07 PM
#60
On the MPG, I would say around 1-2mpg loss, but....one tends to step on the gas more resulting in further loss. It gets addicting but the SRT is also very loud.