After market exhaust headers + P&P intake manifold = ?

riggy30 · 06-11-2008, 12:14 PM

Well guys, I have an 07' STI with a DOM III, FMIC, Meth, injectors, etc., I'll be getting the car dyno-tuned in the near future. Before the dyno-tune though, I would like to add a few more mods to increase the top-end and flatten out the torque curve a bit without doing any major engine work. I already have a Grimmspeed EWG waiting to be installed, if that helps?... Will some exhaust headers and a slight P&P on the intake manifold do anything? This is about the only thing left before any major engine modifications, so that's why I'm asking if it's even worth it... Any suggestions? Thanks!

LSE · 06-11-2008, 04:24 PM

yes it will do something to your power curve which you will like. On stage 2 you get about 15-20whp. However, if you search, you'll find some dyno pulls that show how this gain is not just a peak value, but rather a nice increase across a pretty good rpm range. How much you'll gain is hard to say given you are so moded already. All the charts I've seen have been on the stock turbo.

the debate of P&P vs new headers is long and I kind of side on new headers given you can snatch a set of maddad or gt spec for 450 buck easily.

ninjaboy76 · 06-11-2008, 04:48 PM

I'm sure you would have some decent gains with these mods. Do you have TGV deletes done yet?

Quote:

Originally Posted by LSE

the debate of P&P vs new headers is long and I kind of side on new headers given you can snatch a set of maddad or gt spec for 450 buck easily.

I believe he was referring to a ported and polished intake manifold, not after market headers vs. ported stock exhaust header.

LSE · 06-11-2008, 05:10 PM

Quote:

Originally Posted by ninjaboy76

I'm sure you would have some decent gains with these mods. Do you have TGV deletes done yet?

I believe he was referring to a ported and polished intake manifold, not after market headers vs. ported stock exhaust header.

u're right

misread that one.

riggy30 · 06-12-2008, 04:51 PM

[quote=ninjaboy76;1899440]I'm sure you would have some decent gains with these mods. Do you have TGV deletes done yet?

No, I don't have TGV deletes yet, as I heard they are not really worth it... Plus, they it makes the 07's run like crap on startup... Have you guys seen good gains with TGV deletes?

ninjaboy76 · 06-12-2008, 05:05 PM

Well you sounded like you were looking to get the rest of the power out of your setup before you start looking into engine work. Thats why I suggested TGV deletes. I haven't seen any hard numbers from doing TGV deletes as opposed to not doing them, but they are probably good for around 10whp...maybe. They would certainly help eliminate flow restrictions.

riggy30 · 06-12-2008, 10:14 PM

Thanks guys. After doing some more research, it seems like headers don't really make that much of a difference with larger turbos... Most, if not all tests that I've seen (header related) were on the stock turbo. Is anyone running after market headers with an EWG and a larger turbo? I would really like to see some numbers. Also, after seeing all those dyno-graphs, why the heck do we loose so much power up-top? It surely can't just be the turbo... Even the hp curve was dipping in the high rpm's... Man, subbies suck in the 5-7k rpm range... No wonder why we lose to EVO's all of the time

06-11-2008, 12:14 PM	#1
riggy30 Junior STI Driver Car: Blue 07 WRX STi Fav Mod: Stage II Location: Seattle Posts: 110 Join Date: Dec 2007 Trader Rating: (0)	After market exhaust headers + P&P intake manifold = ? Well guys, I have an 07' STI with a DOM III, FMIC, Meth, injectors, etc., I'll be getting the car dyno-tuned in the near future. Before the dyno-tune though, I would like to add a few more mods to increase the top-end and flatten out the torque curve a bit without doing any major engine work. I already have a Grimmspeed EWG waiting to be installed, if that helps?... Will some exhaust headers and a slight P&P on the intake manifold do anything? This is about the only thing left before any major engine modifications, so that's why I'm asking if it's even worth it... Any suggestions? Thanks! This ad is not endorsed by this member. Please register or login to hide this ad. Last edited by riggy30 : 06-12-2008 at 04:48 PM.

06-11-2008, 04:24 PM	#2
LSE Professional STI Racer Car: 06 STI WRB Fav Mod: Defi Gauges Location: Bethlehem PA Posts: 849 Join Date: Dec 2004 Trader Rating: (0)	Re: Exhaust headers + P&P intake manifold = ? yes it will do something to your power curve which you will like. On stage 2 you get about 15-20whp. However, if you search, you'll find some dyno pulls that show how this gain is not just a peak value, but rather a nice increase across a pretty good rpm range. How much you'll gain is hard to say given you are so moded already. All the charts I've seen have been on the stock turbo. the debate of P&P vs new headers is long and I kind of side on new headers given you can snatch a set of maddad or gt spec for 450 buck easily.

06-12-2008, 04:51 PM	#5
riggy30 Junior STI Driver Car: Blue 07 WRX STi Fav Mod: Stage II Location: Seattle Posts: 110 Join Date: Dec 2007 Trader Rating: (0)	Re: Exhaust headers + P&P intake manifold = ? [quote=ninjaboy76;1899440]I'm sure you would have some decent gains with these mods. Do you have TGV deletes done yet? No, I don't have TGV deletes yet, as I heard they are not really worth it... Plus, they it makes the 07's run like crap on startup... Have you guys seen good gains with TGV deletes?

06-12-2008, 05:05 PM	#6
ninjaboy76 Spec C Club Car: 08 CBR1000RR Fav Mod: None Location: Kansas Posts: 2,430 Join Date: Jun 2004 Trader Rating: (6)	Re: After market exhaust headers + P&P intake manifold = ? Well you sounded like you were looking to get the rest of the power out of your setup before you start looking into engine work. Thats why I suggested TGV deletes. I haven't seen any hard numbers from doing TGV deletes as opposed to not doing them, but they are probably good for around 10whp...maybe. They would certainly help eliminate flow restrictions.

06-12-2008, 10:14 PM	#7
riggy30 Junior STI Driver Car: Blue 07 WRX STi Fav Mod: Stage II Location: Seattle Posts: 110 Join Date: Dec 2007 Trader Rating: (0)	Re: After market exhaust headers + P&P intake manifold = ? Thanks guys. After doing some more research, it seems like headers don't really make that much of a difference with larger turbos... Most, if not all tests that I've seen (header related) were on the stock turbo. Is anyone running after market headers with an EWG and a larger turbo? I would really like to see some numbers. Also, after seeing all those dyno-graphs, why the heck do we loose so much power up-top? It surely can't just be the turbo... Even the hp curve was dipping in the high rpm's... Man, subbies suck in the 5-7k rpm range... No wonder why we lose to EVO's all of the time This ad is not endorsed by this member. Please register or login to hide this ad. Last edited by riggy30 : 06-12-2008 at 10:23 PM.