SC430 HEADER INSTALL THREAD w/PICS, DYNO
Lexus Champion
Joined: Aug 2005
Posts: 2,015
Likes: 2
From: FL
Originally Posted by Pearlpower
Tony
I just pull the negative cable on mine, most people pull the ECU fuse in the box so that their memory settings are not lost. I have found a good solid 1hr will always work. 45 minutes or below gets iffy on resetting everything.
But yes, for each performance mod, reset the ECU. I have noticed improvements this way.
I must say that driving the car is now really a pleasure as the increased power is very evident and intoxicating.
The power is everywhere and I can actually feel the small of my back pressed in the seat. Never got close to that stock. This is going to be a very quick car once the gears,LSD, and TC are in.
I need to finish the airbox for the intake and then start work on those brakes that are sitting in the garage screeming my name.
Lee
I just pull the negative cable on mine, most people pull the ECU fuse in the box so that their memory settings are not lost. I have found a good solid 1hr will always work. 45 minutes or below gets iffy on resetting everything.
But yes, for each performance mod, reset the ECU. I have noticed improvements this way.
I must say that driving the car is now really a pleasure as the increased power is very evident and intoxicating.
The power is everywhere and I can actually feel the small of my back pressed in the seat. Never got close to that stock. This is going to be a very quick car once the gears,LSD, and TC are in.I need to finish the airbox for the intake and then start work on those brakes that are sitting in the garage screeming my name.
Lee
after a reset how many miles do you have to drive before you get the full effect of the mods?
Tony,
MO at SRT says around 50 miles or so and I would concur. Early GS400's had behavioral problems such as erratic shifting, acceleration, etc... and resetting the ECU fixed it. As these ECU learn your driving pattern I suppose that could explain those early GS "mental" issues.
Lee
MO at SRT says around 50 miles or so and I would concur. Early GS400's had behavioral problems such as erratic shifting, acceleration, etc... and resetting the ECU fixed it. As these ECU learn your driving pattern I suppose that could explain those early GS "mental" issues.
Lee
Dyno Results Are In
OK, dyno results are in. Sorry it took a while to post them up.
Keep in mind that these numbers are NOT to be taken are PEAK HP of the car as the dyno I am using produces lower numbers vs actual as explained to me by the shop owner/operator+ throttle was at 90% past the torque peak so TQ numbers are lower. This is more for comparison sake more than anything.
I did a total of 3 sessions. 3 runs each. 9 total not including the bad runs.
Throttle was kept at 90% until 5k RPM then hammered to prevent downshift. All in 4th gear 1:1.
All numbers in standard conversion.
Before header installation with Blitz exhaust, SRT intake/ecu:
Best: (247hp, 256tq) Rear wheel=(309hp, 320TQ)Crank
AFTER header installation dyno with SRT intake/ECU, and Blitz exhaust
Best: (261hp, 278TQ) Rear Wheel=(326 hp,348TQ) Crank
HEADER INCREASE
17HP and 28 lbs TQ
The torque can be felt everywhere and the power band is very nice and progressive..
Figure in that this dyno reads about 5% lower vs. the dyno at another shop I used which was very accurate. So max power now for the car is around 342hp and 365tq.
I will go to my old place to get a peak run as their dyno is very accurate. vs this one used for comparison purposes. All runs were conducted on the same dyno. Until then I will check the Gtech unit shortly to see what it comes up with.
None the less ,17hp and almost 30 lbs of torque is pretty decent in my book. Now again this is a comparison with exhaust and SRT intake/ECU installed in car. I have no idea how a bone stock car will improve with just headers. Sorry. But this does tell you that proven gains can be had on these motors with just bolt ons.
Total cost:
Headers: $595.0+shipping
New OEM gaskets: $40.00 or so
New O2 sensors since I had to splice one to fit anyhow I just replaced both front ones with new units-$130.00 for Bosch units
3 dyno sessions: 3x $75.00=$225.00
Someone buying me a drink in a couple of months at the meet-priceless!
Now there is one very interesting after effect with the dynos. There is a HUGE dip from 5900rpm to 6100rpm then starts to rise again in tq and hp. A/F looks good across the board so that is out. Very odd as this was not present before the headers. It is not felt while driving, and not sure if for some reason his equipment lost RPM signal very briefly in all three runs which i doubt.
Worth it =YES!!!!!!!
I will post the dyno graphs later today as soon as I watermark them.
Put in a real world scenery, a kid locally in a Mustang Mach1 (305hp,320tq-0-60 in 5.4,1/4 in 13.9) with exhaust toasted my SC when it was stock. With SRT/ECU things were closer. Last time we ran with headers installed I stayed with him from 35-70 or so. Things will be different once my gears/LSD (2 days away) and TC are in. But it is good to see a real world improvement vs just graphs.
Now on to the Brembo project.
Lee
Keep in mind that these numbers are NOT to be taken are PEAK HP of the car as the dyno I am using produces lower numbers vs actual as explained to me by the shop owner/operator+ throttle was at 90% past the torque peak so TQ numbers are lower. This is more for comparison sake more than anything.
I did a total of 3 sessions. 3 runs each. 9 total not including the bad runs.
Throttle was kept at 90% until 5k RPM then hammered to prevent downshift. All in 4th gear 1:1.
All numbers in standard conversion.
Before header installation with Blitz exhaust, SRT intake/ecu:
Best: (247hp, 256tq) Rear wheel=(309hp, 320TQ)Crank
AFTER header installation dyno with SRT intake/ECU, and Blitz exhaust
Best: (261hp, 278TQ) Rear Wheel=(326 hp,348TQ) Crank
HEADER INCREASE
17HP and 28 lbs TQ
The torque can be felt everywhere and the power band is very nice and progressive..
Figure in that this dyno reads about 5% lower vs. the dyno at another shop I used which was very accurate. So max power now for the car is around 342hp and 365tq.
I will go to my old place to get a peak run as their dyno is very accurate. vs this one used for comparison purposes. All runs were conducted on the same dyno. Until then I will check the Gtech unit shortly to see what it comes up with.
None the less ,17hp and almost 30 lbs of torque is pretty decent in my book. Now again this is a comparison with exhaust and SRT intake/ECU installed in car. I have no idea how a bone stock car will improve with just headers. Sorry. But this does tell you that proven gains can be had on these motors with just bolt ons.
Total cost:
Headers: $595.0+shipping
New OEM gaskets: $40.00 or so
New O2 sensors since I had to splice one to fit anyhow I just replaced both front ones with new units-$130.00 for Bosch units
3 dyno sessions: 3x $75.00=$225.00
Someone buying me a drink in a couple of months at the meet-priceless!
Now there is one very interesting after effect with the dynos. There is a HUGE dip from 5900rpm to 6100rpm then starts to rise again in tq and hp. A/F looks good across the board so that is out. Very odd as this was not present before the headers. It is not felt while driving, and not sure if for some reason his equipment lost RPM signal very briefly in all three runs which i doubt.
Worth it =YES!!!!!!!
I will post the dyno graphs later today as soon as I watermark them.
Put in a real world scenery, a kid locally in a Mustang Mach1 (305hp,320tq-0-60 in 5.4,1/4 in 13.9) with exhaust toasted my SC when it was stock. With SRT/ECU things were closer. Last time we ran with headers installed I stayed with him from 35-70 or so. Things will be different once my gears/LSD (2 days away) and TC are in. But it is good to see a real world improvement vs just graphs.
Now on to the Brembo project.
Lee
Last edited by Pearlpower; Mar 1, 2006 at 04:32 PM.
Lexus Test Driver
Joined: Dec 2005
Posts: 808
Likes: 9
From: Fl
Nice Gains for your Header Project
Awesome job Lee (as usual)!!!
Thanks for laying the ground work for a lot of us. Uncharted territory is not only risky but it can also be a little scary. And it will get expensive if you get blown off course. You make the possibility a little closer to reality, when considering the Mods. Enjoy your Rocket Roadster!!!
Thanks for laying the ground work for a lot of us. Uncharted territory is not only risky but it can also be a little scary. And it will get expensive if you get blown off course. You make the possibility a little closer to reality, when considering the Mods. Enjoy your Rocket Roadster!!!
Thanks for comments guys. Tony, headers are already priced pretty reasonably, but you never know.......
A/F on the car is good. I think a tad richer could be in order but not sure how much is left. A adjustable AFC would be nice as they can be fine turned to the car so possibly a couple of ponies here and there.
Lee
A/F on the car is good. I think a tad richer could be in order but not sure how much is left. A adjustable AFC would be nice as they can be fine turned to the car so possibly a couple of ponies here and there.
Lee
Pole Position
Joined: Mar 2004
Posts: 285
Likes: 1
From: Canada
Great job lee!! I was expecting some sort of gain, but not 17hp and 30ft/lbs++ thats nuts!! As always the SC community is thankful for you datalogging and dynologging all of this info, SC owners are entering unchartered territory in terms of mods now!
Looking forward to the next project!
Steve
Looking forward to the next project!
Steve
Dyno graphs
OK , here they are. Some explaining. Two different dyno operators from session to session so there was a learning curve for them to achieve best results without kickdown which explains the variations in each session. At least 3 additional runs per session were conducted before these runs were recorded for testing items such as RPM pickup, kickdown,etc...
Notice the dip in the high RPM's on this one? All runs in this session with the headers had this.
The first run-green-was done with only half throttle to check kickdown point.
The dyno operator commented on how nice the power curve was as well as the progressive powerband vs the very jumpy graphs he normally gets from cars that are mod'd.
Enjoy
Lee
Notice the dip in the high RPM's on this one? All runs in this session with the headers had this.
The first run-green-was done with only half throttle to check kickdown point.The dyno operator commented on how nice the power curve was as well as the progressive powerband vs the very jumpy graphs he normally gets from cars that are mod'd.
Enjoy
Lee
Last edited by Pearlpower; Mar 1, 2006 at 11:32 PM.