mazzuri super headers
I'm sure there is some significance behind the fact that you now get a 2nd gear chirp, but I wonder what that really tells us. Mine chirp from time to time, but that is usually when it's cold (more power and less grippy tires) or on asphalt (less grippy road). Obviously, in a car with a manual transmission, chirping the tires in 2nd has a whole lot more to do with really grabby clutches, heavier flywheels, and limitted traction than it does engine torque or HP. I would guess that the same would be true to an extent with automatics too.
Oh well, I'm really looking forward to the dyno results.
Oh well, I'm really looking forward to the dyno results.
Your lower profile tires are 19's right? If so, they would probably be harder to chirp than the stockers. My current tires are easier to chirp because the overall outer diameter is 1" smaller than stock which gives more thrust to the ground.
Rookie
Joined: Feb 2006
Posts: 72
Likes: 0
From: belgium
OK,while we are waiting for more dyno-results ,i would like to know if all the IS250 owners with the mazzuri headers are happy with it, and can drive without any problems.They must feel much more the gain with the IS250 than the IS350 owners.Am i wright or just another Is250 owner who thinks his car will go faster with the headers???(maybe ordering this week)
Driver
Joined: Oct 2006
Posts: 159
Likes: 0
From: CA
Just talked to Troy and he said the car actually lost some power/tq with the new header. So one of two things is happening here:
1. Since his car still has a CEL from not having a sim, that may be causing some problems as far as how the car makes power. Some more testing with the scanner should tell us the whole story.
2. Going with the bigger tubing may have done more bad than good. The drop in velocity may have been too big, as the math shows 1.5" to be ideal for this motor.
I want to see what the scanner shows, but so far looks like the v1 header is better than the second.
1. Since his car still has a CEL from not having a sim, that may be causing some problems as far as how the car makes power. Some more testing with the scanner should tell us the whole story.
2. Going with the bigger tubing may have done more bad than good. The drop in velocity may have been too big, as the math shows 1.5" to be ideal for this motor.
I want to see what the scanner shows, but so far looks like the v1 header is better than the second.
Lexus Test Driver
Joined: Sep 2007
Posts: 1,097
Likes: 0
From: Dallas
yes 19's, i usually only chirp them when my tires are cold now, but i used to be able to every now and then with my stock set up.. like racing around town when id smash it from a light or something, and they would spin some off the line then they would chirp when it shifted into second gear
Pole Position
Joined: Feb 2007
Posts: 276
Likes: 0
From: CA
Just talked to Troy and he said the car actually lost some power/tq with the new header. So one of two things is happening here:
1. Since his car still has a CEL from not having a sim, that may be causing some problems as far as how the car makes power. Some more testing with the scanner should tell us the whole story.
2. Going with the bigger tubing may have done more bad than good. The drop in velocity may have been too big, as the math shows 1.5" to be ideal for this motor.
I want to see what the scanner shows, but so far looks like the v1 header is better than the second.
1. Since his car still has a CEL from not having a sim, that may be causing some problems as far as how the car makes power. Some more testing with the scanner should tell us the whole story.
2. Going with the bigger tubing may have done more bad than good. The drop in velocity may have been too big, as the math shows 1.5" to be ideal for this motor.
I want to see what the scanner shows, but so far looks like the v1 header is better than the second.
That is disappointing, but it will be interesting to see the plots anyway, especially with before / after AFR's. As I mentioned earlier, some cars run rich when there is a DTC for secondary O2's. It wouldn't surprise me at all if fixing the sim improved the dyno results.
Yeah, I am going to go up there this afternoon and pull the files off their machine. It was crashing while i was trying to rip it to my camera.
I'll post up the pep sae tonight.
piping sizes aside, just removal of the cats should have done at least 6hp. I'll log with carchitect sometime this weekend or something and compare it to the pre header install
I'll post up the pep sae tonight.
piping sizes aside, just removal of the cats should have done at least 6hp. I'll log with carchitect sometime this weekend or something and compare it to the pre header install
Daniel has been a straight shooter from the very start. Agreed with the comments above.
OK I have made a public online file share account for you nerds that want the run files.
http://www.4shared.com/dir/7811910/a...b/sharing.html
if it ask for a user/pass just PM me for those credentials.
runs 3,4,5 are from 5/17 (pre header install)
runs 7,9,10 are from 6/25 (post header install)
1. 3 pulls today after header install and 75 miles on car w/cel on.
2. Here are the before and after runs on one graph. I tried to change the runs from 5/17 to all blue, and the ones from today to all black, but the winpep software I have doesn't let me do them all. One of you guys might be able to figure it out.
http://www.4shared.com/dir/7811910/a...b/sharing.html
if it ask for a user/pass just PM me for those credentials.
runs 3,4,5 are from 5/17 (pre header install)
runs 7,9,10 are from 6/25 (post header install)
1. 3 pulls today after header install and 75 miles on car w/cel on.
2. Here are the before and after runs on one graph. I tried to change the runs from 5/17 to all blue, and the ones from today to all black, but the winpep software I have doesn't let me do them all. One of you guys might be able to figure it out.
Last edited by combfilter; Jun 25, 2008 at 01:39 PM.
