561Lexus

So can anyone explain to me what headers would do for me? I have the F-Sport Intake and Exhaust... If I added on the Megan Racing Headers, what does this do for me? Sound and Performance-wise? Thanks guys!

Kurtz

iTrader: (1)

The megan ones? Probably not much. At least I've never seen any objective evidence of a gain, despite them being around for over 5 years.

The PPE ones on the other hand would add about 15-20 hp... (and likely some more sound since you'd be replacing, or removing entirely, the factory front cats)

Note that they're not legal in any US state, but if you don't live someplace with emissions inspections you're unlikely to ever get caught.

NafisC

I believe the PPE's have only shown that 15-20hp increase on the IS350...(Someone correct me if I'm wrong). The headers would add some better/louder sound, as it deletes the stock cats, but before you continue your quest for headers, perhaps you should look into finishing the length of the piping. (Mid Pipes)

Kurtz

iTrader: (1)

Ok, you're wrong

They actually showed a larger gain on the 250 than the 350.

http://www.ppeengineering.com/products/lexus/is250.php

http://www.ppeengineering.com/products/lexus/is350.php

Note in both cases the test cars had aftermarket intake and exhaust systems on em (both before and after) so it's entirely possible the gains would be smaller on a totally stock car making no change but the PPE headers.... I don't think I've seen any dynos of the headers on an otherwise stock 250 or 350... but I'd expect there to still be decent gains.

The megan headers on the other hand, which have existed years longer, I've never seen any dyno gains posted at all.

BernieIS

iTrader: (1)

Perhaps you guys could learn to read and pick up details that are important. All thought either set will fit any 2IS except the ISF the Megan are designed for the IS250 where the PPE are designed for the IS350. These engines are completely different and you should be using the parts that are designed for your car. As far as performance goes you will not see significant gains with these.

PPEHeaders

iTrader: (4)

Hi guys,

We actually have two different versions. One for the IS250 and one for the IS350. The tubing sizes are different due to the power differences in the engines. The tube routing and overall lengths are the same.

The IS350 has 1.75" OD tubing and the IS250 has 1.625" OD tubing.

Our IS350 headers made ~16whp gains over stock.

Our IS250 headers made ~18whp gains over stock.

BernieIS

iTrader: (1)

This is great information. Thanks for that up.

NCLexi250

iTrader: (1)

Great information indeed! Any word on the ones for the awd models?

Thanks.

PPEHeaders

iTrader: (4)

The IS250AWD version is very similar to the standard version. Tubes are 1.625" OD but are a bit shorter in order to clear the front driveshaft. Power gains should be similar.
I don't see us doing dyno testing on the AWD because it took so long to find a car to come in for prototyping. The car had codes in the ECU when it came in so we couldn't do any dyno testing at that time.