Headers for V8 cars, Please read
Pole Position
Joined: Jan 2004
Posts: 374
Likes: 0
From: Florida
i guess the reason we are making a "commitment list" is because after the initial batch there will be no more right? otherwise they can be pretty much made to order using the same mold that the "committed" got...the reason i ask is because i dont like to purchase things without knowing what the benefits are and what implications come with those benefits...
in other words i like to read reviews of products before i buy...so will these be available after the "committed" buy theirs?
in other words i like to read reviews of products before i buy...so will these be available after the "committed" buy theirs?
Lead Lap
Joined: Nov 2004
Posts: 441
Likes: 0
From: Alberta
Originally Posted by Fisher503
Could we get a list of GS430 Guys who would definitely do this if they new it could bolt on to yor car right out of the box?
1. Fisher503
1. Fisher503
Lead Lap
Joined: Nov 2004
Posts: 441
Likes: 0
From: Alberta
Originally Posted by Hameed
Great fodder indeed! Maybe my head is up my ar## or something, but I don't understand all this major excitement over 20 RWHP............... 
Not trying to sound negative or cynical about that gain, but would you really notice 20 additional RWHP?
Not trying to sound negative or cynical about that gain, but would you really notice 20 additional RWHP?
There are some people on the forum who are happy with just the exhaust, for sound resons.
Then there are people who want more NA power. This is done with intake side and exhaust side mainly. Now if you add an intake you increase the amount of air going in, now if the headers are resrtictive, the intake can only flow as much as what the head will flow combined with how well the exhaust gasses get scavenged through the header and restrictive cats, especially ones close to a header make things even worse. Right now a cat back exhaust for our cars does not yeild that much gains because of this.
So if you got these headers, got a custom Y pipe with a free flow cat, to a good cat back exhaust you will make some rather impressive numbers on a V8, far more that 20 whp. Pluss add the SRT intake and you are off to the races. To go even further an ECU tune would complete the job!
Pit Crew
Joined: Apr 2005
Posts: 122
Likes: 0
From: AR
Originally Posted by Fisher503
Could we get a list of GS430 Guys who would definitely do this if they new it could bolt on to yor car right out of the box?
1. Fisher503
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1. Fisher503
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If it is fully bolt on I will jump on it if its $600ish
Lexus Test Driver
Joined: Mar 2001
Posts: 1,139
Likes: 0
From: California
Originally Posted by Hollywood
To go even further an ECU tune would complete the job!
Brent
Lexus Champion
Joined: Feb 2001
Posts: 3,124
Likes: 32
From: Texas
It is true we will not know the power gain until these headers are installed and tested. However it is interesting to note that the difference between the 290hp/300tq rating of my LS400 and the 300hp/310tq rating of the GS400 is mostly in the 0.39" in the single center exhaust pipe diameter (1.97" vs 2.36").
For me, it is difficult knowing that there is "free" horsepower trapped in this engine. Free in that the engine will happily make it if we only remove limiting factors such as lousy manifolding. The intake manifold is a beautiful work of art. The only explanation for the exhaust manifolding is that Lexus wanted to restrict the output of the engine coupled with manufacturing limitations and emissions regulations. MOST other performance oriented engines from the factory have decent exhaust manifolding. If this was the case with our engine I would not be making this effort.
Personally, I will be surprised if the gain is less than 20rwhp. I would be pleased but not shocked to see 30rwhp.
An example would be a Ford 5.0 I built years ago. Rated at 225hp they typically make 180-190rwhp. With 1.5" shorty headers replacing the stock crimped headers and mild porting of the stock heads (still less flow than the 1UZFE) my engine dyno'd at 249rwhp and 314rwtq. This is a gain of 60-70rwhp. Significant was that peak power with stock valvesprings was at a very low 4600rpm. As RPM goes up, if torque does not drop off, power goes up. Our engines at 6000rpm have a greater need for efficient exhaust than my example. Now, I am NOT suggesting a 60hp gain. But there are more than a few engines making over 100hp/liter with a similar layout to the 1UZFE. This would require more RPMs and more valve flow but without decent exhaust manifolding you can forget it. BTW the porting I did on the Ford heads above did NOT increase the size of the intake port at the intake manifold and barely increased the exhaust size. Instead of making bigger ports I made them flow more. Same idea here.
All this is speculation. Time will tell.
As far as additional runs of headers after the first... I can't say. The builder must run batches of 20 at least to make economic sense. Will more be available later? Depends on the demand.
Would you feel 20rwhp? Absolutely. I would compare it to the difference between how our engines run in cool crisp air vs. hot humid air. You know how sometimes these things FEEL so strong and other times we are dissapointed? That would be around 20rwhp. Now, of course these engines will still have a range dependent on environment but it will be moved UP so that the low range will be our current TOP range
.
For me, it is difficult knowing that there is "free" horsepower trapped in this engine. Free in that the engine will happily make it if we only remove limiting factors such as lousy manifolding. The intake manifold is a beautiful work of art. The only explanation for the exhaust manifolding is that Lexus wanted to restrict the output of the engine coupled with manufacturing limitations and emissions regulations. MOST other performance oriented engines from the factory have decent exhaust manifolding. If this was the case with our engine I would not be making this effort.
Personally, I will be surprised if the gain is less than 20rwhp. I would be pleased but not shocked to see 30rwhp.
An example would be a Ford 5.0 I built years ago. Rated at 225hp they typically make 180-190rwhp. With 1.5" shorty headers replacing the stock crimped headers and mild porting of the stock heads (still less flow than the 1UZFE) my engine dyno'd at 249rwhp and 314rwtq. This is a gain of 60-70rwhp. Significant was that peak power with stock valvesprings was at a very low 4600rpm. As RPM goes up, if torque does not drop off, power goes up. Our engines at 6000rpm have a greater need for efficient exhaust than my example. Now, I am NOT suggesting a 60hp gain. But there are more than a few engines making over 100hp/liter with a similar layout to the 1UZFE. This would require more RPMs and more valve flow but without decent exhaust manifolding you can forget it. BTW the porting I did on the Ford heads above did NOT increase the size of the intake port at the intake manifold and barely increased the exhaust size. Instead of making bigger ports I made them flow more. Same idea here.
All this is speculation. Time will tell.
As far as additional runs of headers after the first... I can't say. The builder must run batches of 20 at least to make economic sense. Will more be available later? Depends on the demand.
Would you feel 20rwhp? Absolutely. I would compare it to the difference between how our engines run in cool crisp air vs. hot humid air. You know how sometimes these things FEEL so strong and other times we are dissapointed? That would be around 20rwhp. Now, of course these engines will still have a range dependent on environment but it will be moved UP so that the low range will be our current TOP range
.
Pole Position
Joined: Jan 2004
Posts: 374
Likes: 0
From: Florida
very compelling info jbrady...
how soon will this be available for the GS430? and by the way about how much is a good installer gonna charge for such a project? for $600 its definately worth a shot...
how soon will this be available for the GS430? and by the way about how much is a good installer gonna charge for such a project? for $600 its definately worth a shot...
Lead Lap
Joined: Nov 2004
Posts: 441
Likes: 0
From: Alberta
Originally Posted by jbrady
It is true we will not know the power gain until these headers are installed and tested. However it is interesting to note that the difference between the 290hp/300tq rating of my LS400 and the 300hp/310tq rating of the GS400 is mostly in the 0.39" in the single center exhaust pipe diameter (1.97" vs 2.36").
For me, it is difficult knowing that there is "free" horsepower trapped in this engine. Free in that the engine will happily make it if we only remove limiting factors such as lousy manifolding. The intake manifold is a beautiful work of art. The only explanation for the exhaust manifolding is that Lexus wanted to restrict the output of the engine coupled with manufacturing limitations and emissions regulations. MOST other performance oriented engines from the factory have decent exhaust manifolding. If this was the case with our engine I would not be making this effort.
Personally, I will be surprised if the gain is less than 20rwhp. I would be pleased but not shocked to see 30rwhp.
An example would be a Ford 5.0 I built years ago. Rated at 225hp they typically make 180-190rwhp. With 1.5" shorty headers replacing the stock crimped headers and mild porting of the stock heads (still less flow than the 1UZFE) my engine dyno'd at 249rwhp and 314rwtq. This is a gain of 60-70rwhp. Significant was that peak power with stock valvesprings was at a very low 4600rpm. As RPM goes up, if torque does not drop off, power goes up. Our engines at 6000rpm have a greater need for efficient exhaust than my example. Now, I am NOT suggesting a 60hp gain. But there are more than a few engines making over 100hp/liter with a similar layout to the 1UZFE. This would require more RPMs and more valve flow but without decent exhaust manifolding you can forget it. BTW the porting I did on the Ford heads above did NOT increase the size of the intake port at the intake manifold and barely increased the exhaust size. Instead of making bigger ports I made them flow more. Same idea here.
All this is speculation. Time will tell.
As far as additional runs of headers after the first... I can't say. The builder must run batches of 20 at least to make economic sense. Will more be available later? Depends on the demand.
Would you feel 20rwhp? Absolutely. I would compare it to the difference between how our engines run in cool crisp air vs. hot humid air. You know how sometimes these things FEEL so strong and other times we are dissapointed? That would be around 20rwhp. Now, of course these engines will still have a range dependent on environment but it will be moved UP so that the low range will be our current TOP range .
For me, it is difficult knowing that there is "free" horsepower trapped in this engine. Free in that the engine will happily make it if we only remove limiting factors such as lousy manifolding. The intake manifold is a beautiful work of art. The only explanation for the exhaust manifolding is that Lexus wanted to restrict the output of the engine coupled with manufacturing limitations and emissions regulations. MOST other performance oriented engines from the factory have decent exhaust manifolding. If this was the case with our engine I would not be making this effort.
Personally, I will be surprised if the gain is less than 20rwhp. I would be pleased but not shocked to see 30rwhp.
An example would be a Ford 5.0 I built years ago. Rated at 225hp they typically make 180-190rwhp. With 1.5" shorty headers replacing the stock crimped headers and mild porting of the stock heads (still less flow than the 1UZFE) my engine dyno'd at 249rwhp and 314rwtq. This is a gain of 60-70rwhp. Significant was that peak power with stock valvesprings was at a very low 4600rpm. As RPM goes up, if torque does not drop off, power goes up. Our engines at 6000rpm have a greater need for efficient exhaust than my example. Now, I am NOT suggesting a 60hp gain. But there are more than a few engines making over 100hp/liter with a similar layout to the 1UZFE. This would require more RPMs and more valve flow but without decent exhaust manifolding you can forget it. BTW the porting I did on the Ford heads above did NOT increase the size of the intake port at the intake manifold and barely increased the exhaust size. Instead of making bigger ports I made them flow more. Same idea here.
All this is speculation. Time will tell.
As far as additional runs of headers after the first... I can't say. The builder must run batches of 20 at least to make economic sense. Will more be available later? Depends on the demand.
Would you feel 20rwhp? Absolutely. I would compare it to the difference between how our engines run in cool crisp air vs. hot humid air. You know how sometimes these things FEEL so strong and other times we are dissapointed? That would be around 20rwhp. Now, of course these engines will still have a range dependent on environment but it will be moved UP so that the low range will be our current TOP range
.
It's 18 months since this thread began.
Not sure if I have this right, but after all this time we're at a prototype of the driver's side header only, no indication of what we might expect power wise although jbrady's theory makes sense that it ought to be good, plus maybe I missed it but we don't know how hard it will be to install this thing on a GS400 (whether the engine will have to be pulled). Is that right?
What's the exact sequence from here out? Are we now waiting for a prototype passenger side? Is the kit only going to be the driver's side?
jbrady - what is your best guess as to when those on the list might receive headers?
Not sure if I have this right, but after all this time we're at a prototype of the driver's side header only, no indication of what we might expect power wise although jbrady's theory makes sense that it ought to be good, plus maybe I missed it but we don't know how hard it will be to install this thing on a GS400 (whether the engine will have to be pulled). Is that right?
What's the exact sequence from here out? Are we now waiting for a prototype passenger side? Is the kit only going to be the driver's side?
jbrady - what is your best guess as to when those on the list might receive headers?
Lexus Champion
Joined: Feb 2001
Posts: 3,124
Likes: 32
From: Texas
Originally Posted by bitkahuna
It's 18 months since this thread began.
Not sure if I have this right, but after all this time we're at a prototype of the driver's side header only, no indication of what we might expect power wise although jbrady's theory makes sense that it ought to be good, plus maybe I missed it but we don't know how hard it will be to install this thing on a GS400 (whether the engine will have to be pulled). Is that right?
What's the exact sequence from here out? Are we now waiting for a prototype passenger side? Is the kit only going to be the driver's side?
jbrady - what is your best guess as to when those on the list might receive headers?
Not sure if I have this right, but after all this time we're at a prototype of the driver's side header only, no indication of what we might expect power wise although jbrady's theory makes sense that it ought to be good, plus maybe I missed it but we don't know how hard it will be to install this thing on a GS400 (whether the engine will have to be pulled). Is that right?
What's the exact sequence from here out? Are we now waiting for a prototype passenger side? Is the kit only going to be the driver's side?
jbrady - what is your best guess as to when those on the list might receive headers?
Your intentions may be good but I don't think you have been following this thread. Passenger side was the first side done.
Yes it has been a long time and no excuses but if you really want to get up to speed at least read my posts starting on page 22 with post 325.
Lexus Champion
Joined: Feb 2001
Posts: 3,124
Likes: 32
From: Texas
Originally Posted by Mrbig
Add me to the list of GS430 owners !!!
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