I would check for an exhaust leak although some people tell me I am full of BS when I say I smell exhaust but I defiantly do smell it. A couple times my wife has said she smells it on my clothes but in no way is it as bad as you're describing. Mine is very faint and usually just noticeable at stop lights and I never drive with any windows open so hopefully you something else going on that can be solved....

 

Aftermarket headers will definitely give you more power more than an exhaust will. Even with the stock exhaust on.
I custom made my exhaust , two pipes all the way, 1 mid muffler with internal xpipe, and stock rear mufflers modified to 2.5 inch inlets

probably lose 5whp with stock mufflers but no matter what i do to the car they keep the noise down near stock level

 

By any chance, do you got any pics of your setup?

 

Yes i will take some tomorrow 18th Feb up on hoist.
Pm me your number ill send you the pics and try getting them up on here too

From my research on these forums i know it will only get louder with headers so all the more reason for me to do this, im over loud exhausts.

Ill also send pics of primary cats removed from factory headers. I am removing factory headers, cutting off the cats (add flanges to add back anytime), fitting on straight pipes.
Autowerks in Beverly Hills can now remove the CEL in the ecu table for $190.00 and flash tune if needed for $1990.00.
Then weld back on 100cpi secondary cats (for the smell)

I have found 3 threads with proof of same power gains by removing the primary cats as PPE headers do. Advantage is you save $3500 which lexus of chatwood charge to supply and fit them. Price being so high because the AUD is so weak against the USD.

Again the PPE may gain a few more HP (which i have not seen) but whatever it may be its not worth the $$$. Youll get more by spending it on a tune.

Ill post a dyno of my custom exhaust and header setup without a tune.

 

Must be a reason that RRRacing is now a PPE distributer

Lou

 

Absolutely but the benefits for the $$ we need to spend down here not worth it for what i use the ISF for. If our $AUD was any better i would love to get PPE.

 

Guys, when anyone asks us about the gains of headers over stock decat manifolds, we are always 100% honest. On the dyno, you can expect 6-12hp additional with headers on a car with our ECU tune. Some may scoff at that and say the hp/$ is not worth it... to each his own!

The reason we are selling PPE headers is four fold, (1) we asked customers if they felt that the additional HP is worth it for them, and many answer yes... (2) PPE makes a very high quality product, (3) some folks want to keep the OEM exhaust manifolds intact in case they have to revert back to stock when they move back from Mexico, and (4) there is also the "sound" component which many people really like.

We are very careful not to make pie-in-the-sky claims of 20-30hp additional hp from headers vs. gutted OEM manifolds... that is simply not true. And we have also observed that the relative before/after gains from the tune are greater with the decat OEM manifolds vs. the headers -- we reported that as well, and you can clearly see this in our tuned dyno results.

Rafi

 

I think some guys on this forum can't or don't want to come to the realization that they spent over $3500.00 to get 400whp , but by just deleting all oem cats and res you get equal or more power for less than $900.00 bucks !!!!

 

This is the info I was looking for . Someone mentioned that the car will go in lip mode by removing the primary cats but if that is not the case I will gut my primary cats. I just want to see what gains I will have with just the tune.

Thanks Raffi

 

I imagine the tune will lean the car out a little bit and help with the smell.

 

Good info, considering the header car you guys tuned made 411whp same dyno correct?

So only +6whp more, that's very little gains to spend an additional $2000+ for full headers and install.

It seems the RR tune makes up for most of the deficiencies between the stock decatted vs. full header, that's very impressive and shows you what a good tune can do.

Looks like the most performance per dollar would be Full exhaust, de-catted stock manifolds + RR Racing Tune.

 

Amen to that

 

I'd want to compare area under the curve before absolutely discounting it...but based on sound and install price, I doubt I'll ever throw down the pennies for an aftermarket header.

 

That's a very good point. 6hp peak is not much at all but there could be other gains under the curve.

 

There, I fixed it for you

-Mike