When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
My 1999 LS400 is quicker and faster than my 2004 LS430!
I took my LS430 to Houston Raceway Park for Fridays street drag racing. Do to the number of cars and so many that broke while racing requiring lengthy cleanups I was only able to get 2 runs in. Nearly identical times in nearly perfect 60 degree air... 14.54et @ 95.41mph. I put it on the scale and without me it weighed 3980lbs. WHY with a larger engine, more torque "better" gearing and very similar weights... was it slower than my 1999 LS400 which I ran in nearly the same conditions at the same track to a 14.22 @ 99.38?
Now, to be fair, I feel like I could probably get this car down to the 14.22 elapsed time with higher rpm launching and taking the golf clubs and other extras out of the trunk BUT that still does not make up the extra 4 mph which in drag racing take horsepower. The reason is the engines different power curve and the gearing! The 3.77 axle ratio coupled with 12.3 first gear ratio and the 25" diameter tires does deliver a quicker 0-60 and in fact it was quicker in the 60ft times 2.13 vs 2.2 but it also shifts into 2nd gear at 37mph where the 400 stays in 1st gear until 45mph. 2nd-3rd difference is 63mph vs 70mph. 3rd to 4th is a 91mph while the 400 stays in 3rd through the traps at 99mph not shifting into 4th until 107mph.
From 107 to 123mph the 430 is quicker but tops out at 131mph on the limiter.
From 123 to 131mph the 400 is quicker and continues on to its limited top speed of 149mph.
Now, the power curves, yes at 315ft/lb of torque the 430 has the advantage over the 300lb/ft or torque for the 400 BUT since the 430 has peak torque at 3400rpm this only is seen in first gear since the full throttle RPM range for the following gears are 2nd gear 4000-6250, 3rd gear 3900-4000, 4th gear 4200-5400. Since the 400 has peak torque of 300 at 4000rpm and peak power at 6000rpm it is actually geared better as far as average power in each gear.
The SOLUTION… Add the S&S Headers I have new in box! VS the very restrictive log style 430 manifolds the headers will likely lift the peak power from 5600rpm up to 6000rpm and gain somewhere around 20-25rwph!
Hey Stroock639, yeah, the intake mod is simple and it works! The 430 intake is different and it doesn't have an easy mod option.
Hey oldskewel, yup, drove from the course to the track! Had to get a helmet because "track rules" require it with a "glass roof". Yet, 12 second truck drivers can go without helmets...
I took my LS430 to Houston Raceway Park for Fridays street drag racing. Do to the number of cars and so many that broke while racing requiring lengthy cleanups I was only able to get 2 runs in. Nearly identical times in nearly perfect 60 degree air... 14.54et @ 95.41mph. I put it on the scale and without me it weighed 3980lbs. WHY with a larger engine, more torque "better" gearing and very similar weights... was it slower than my 1999 LS400 which I ran in nearly the same conditions at the same track to a 14.22 @ 99.38?
Now, to be fair, I feel like I could probably get this car down to the 14.22 elapsed time with higher rpm launching and taking the golf clubs and other extras out of the trunk BUT that still does not make up the extra 4 mph which in drag racing take horsepower. The reason is the engines different power curve and the gearing! The 3.77 axle ratio coupled with 12.3 first gear ratio and the 25" diameter tires does deliver a quicker 0-60 and in fact it was quicker in the 60ft times 2.13 vs 2.2 but it also shifts into 2nd gear at 37mph where the 400 stays in 1st gear until 45mph. 2nd-3rd difference is 63mph vs 70mph. 3rd to 4th is a 91mph while the 400 stays in 3rd through the traps at 99mph not shifting into 4th until 107mph.
From 107 to 123mph the 430 is quicker but tops out at 131mph on the limiter.
From 123 to 131mph the 400 is quicker and continues on to its limited top speed of 149mph.
Now, the power curves, yes at 315ft/lb of torque the 430 has the advantage over the 300lb/ft or torque for the 400 BUT since the 430 has peak torque at 3400rpm this only is seen in first gear since the full throttle RPM range for the following gears are 2nd gear 4000-6250, 3rd gear 3900-4000, 4th gear 4200-5400. Since the 400 has peak torque of 300 at 4000rpm and peak power at 6000rpm it is actually geared better as far as average power in each gear.
The SOLUTION… Add the S&S Headers I have new in box! VS the very restrictive log style 430 manifolds the headers will likely lift the peak power from 5600rpm up to 6000rpm and gain somewhere around 20-25rwph!
Good and thorough effort! I certainly had my doubts about seeing much gain from EH but for whatever reason both your report on how the car drives and the dyno testing is excellent evidence of a success. I will definitely consider the option. For starters I intend to install the S&S Headers aka JBrady Headers that I have had in a box for many a year now. They were intended for the 99 but as miles increased and bushings wore out it just doesn't get driven hard like I once did. That said it definitely seems to rev much better than the 430 as that motor is torque-er but hits peak power at 5600. The 430 log manifolds are an emission item certainly not a performance item.
Good and thorough effort! I certainly had my doubts about seeing much gain from EH but for whatever reason both your report on how the car drives and the dyno testing is excellent evidence of a success. I will definitely consider the option. For starters I intend to install the S&S Headers aka JBrady Headers that I have had in a box for many a year now. They were intended for the 99 but as miles increased and bushings wore out it just doesn't get driven hard like I once did. That said it definitely seems to rev much better than the 430 as that motor is torque-er but hits peak power at 5600. The 430 log manifolds are an emission item certainly not a performance item.
The "log" exhaust manifold is indeed an emissions item...the less surface area, the faster it heats up and the catalytic converter reaches operating temperature.
Have considered using headers, however the tube diameters on these headers appears to be slightly too large and so low end torque may suffer.
The other thing is thermal management....
Thermal coatings on exhaust headers tends to embrittle metal and promote cracking.at joints.
The OEM uses metal heat shields to increase thermal efficiency and flow velocity...
Heat shields on the headers would make a lot of sense.
Hey Stroock639, yeah, the intake mod is simple and it works! The 430 intake is different and it doesn't have an easy mod option.
Hey oldskewel, yup, drove from the course to the track! Had to get a helmet because "track rules" require it with a "glass roof". Yet, 12 second truck drivers can go without helmets...
funny how that works isnt it. yes the 400 is quicker then the 430. quicker then the 460 as well. 500 is pretty fast off the line but looses steam once its 85+ on the highway like most modern cars are these days. cruising at 120 in a 400, if i stomp it it still pulls like hell and they really dont start to slow down till about 140ish. 140-160 is a crawl though.
funny how that works isnt it. yes the 400 is quicker then the 430. quicker then the 460 as well. 500 is pretty fast off the line but looses steam once its 85+ on the highway like most modern cars are these days. cruising at 120 in a 400, if i stomp it it still pulls like hell and they really dont start to slow down till about 140ish. 140-160 is a crawl though.
Hey Stereorob, do you have data on the 400 vs the 460? When I drove a 460 I was expecting it to be noticeably faster than the 400 since it has 102 more horsepower... but it felt about the same... definitely disappointing.
For those wondering in 2006 Lexus (and others) changed the way they rated engine power which resulted in a lower RATED number for the same engine. 2005 LS430 = 290hp rated, 2006 LS430 = 278hp rated, both engine are identical and make the same power. So, the 1998-00 LS400 rated at 290hp would be 278hp using the changed rating system implemented in 2006.
04-22-19, 01:34 PM
My 1999 LS400 is quicker and faster than my 2004 LS430!
