I just wonder if there are a lot of is250 owners with the headers(mazzuri/jun..)
and if they are happy with it.Did you feel the gain? did anyone dynoed it for himself.maybe i going to order a set mazzuri's but as i live in europe/belgium i will not have any support here.I have a friend who can put them in my car but i want to be 100% sure that everything works fine.i tought i would test the car by running on the highway in 5th and floor it from 75m/h to 125miles/h and count the seconds.

 

I have a set of the Mazzuri headers for the AWD IS250. I just received revision 2 which was modified to fit around the front drive shaft. I should have them bolted up somtime in the month of July but probably won't get to the dyno shop until mid-August as I have vaction plans for the end of July.

I have already done the base-line dyno runs so I should have a good understanding of how these headers perform. There will be two major (minor?) differences between my header and the 2WD version. 1st is that the primaries for the AWD set are shorter. 2nd is that I am having them ceramic coated as well.

It would give you a better understanding if you can wait for my data. However that is your call.

Maybe some 2WD guys will chime in???

 

ANYONE ELSE???????or is there only one sold??

 

im probably going to buy a set as soon as mazzuri gets them in stock. ill be sure to let you guys know

 

I would not Ceramic coat your headers because the increased heat retention
will cause the timing to retard to prevent knock.

 

I don't believe that for one second, no way.

The heat sink properties of the OEM manifolds or an aftermarket header for that matter are minimal compared with a liquid cooled engine with aluminum head/block. The metal mass is not sufficient etc….

The shielding effect that the coating has will reduce the ambient air temperatures in the engine bay which will allow the whole engine and cooling system to perform better. But I think only measurement equipment would be able to notice a difference.

The exhaust gas will stay hotter after it exits the head as it travels back to the tailpipe. But this is after the fact. Since is stays hotter, it should have more velocity which generally makes more power.

 

too late , i ordered mine this week and i will wait to install them till august after my hollidays.But i'm still not sure if i'am going to dyno the car.It has been done allmost 2years ago when k&n installed the typhoonkit(was the first in europe.gave me 5to7hp extra).i don't think that i can compare it to those figures.Is timing in 5th gear from 75 to 125miles/h a good way?

 

Cool!!! glad to here that you went through with it. That’s got to be some expensive shipping, huh???

I don't think that measuring the acceleration time is going to be very accurate but it is a little better then the butt-dyno test.

The weather conditions as well as measurement error are going to affect your timing a lot.

Good luck,

 

It will be shipped next week.don't forget that the is a difference in the valuta euro/us dollar.Daniel takes care off the shipment so no wories for me just the payment.
Can i trust the dyno off 1,5 years ago from K&N and only make a dyno after the changes??

 

The K&N dyno? No way, I would never use a manufacturers dyno numbers as a baseline for evaluating modifications to your own vehcile. They are usually not accurate by a long shot.

If you don't want to do a baseline than you could use the "before" dyno numbers that Daniel and I have posted elsewhere. This would give to a very general idea as his car was RWD and mine was AWD. But it would be a better reference then the K&N numbers for sure.

 

Got a mail this morning " Headers are shipped to you!!"
they wil arrive in 10days.I will fit after my hollidays first week of august.
Still looking to dyno or not.I'll try to post the dyno off K&N

 

If the base dyno wasn't done on your car it's not a reliable comparison.

If the base dyno was done by a large manufacturer trying to sell you their intake then it's completely useless for comparison because they're generally lying.

 

Here is a picture off the dyno.please note that this dyno was made on my car and is a before and after and is made by K&N europe.
http://gallery.mac.com/martinebekaert#100020