2.5 headers

[ghostrider300]

Hi everybody. I'd like to know from people who have headers on their cars how they like them. How much louder did they make the car and did the claimed hp pass the butt dyno test? I have heard there are issues with this modification, I'm looking for all feedback, thanks.

[blinkwatt]

Hi everybody. I'd like to know from people who have headers on their cars how they like them. How much louder did they make the car and did the claimed hp pass the butt dyno test? I have heard there are issues with this modification, I'm looking for all feedback, thanks.

Most of the time if there is an issue with headers on a Boxster it's on the e-gas 2.7 or 3.2L engine with a o2 configuration in each header.

2.5L engine do not have the 02 sensors located in the header design and the only thing there is to worry about is the headers fitting properly.

[ghostrider300]

Hi everybody. I'd like to know from people who have headers on their cars how they like them. How much louder did they make the car and did the claimed hp pass the butt dyno test? I have heard there are issues with this modification, I'm looking for all feedback, thanks.

Most of the time if there is an issue with headers on a Boxster it's on the e-gas 2.7 or 3.2L engine with a o2 configuration in each header.

2.5L engine do not have the 02 sensors located in the header design and the only thing there is to worry about is the headers fitting properly.

Thanks, I was aware of the O2 issue with the later models, I had read once elsewhere that aftermarket headers required frequent changes of exhaust gaskets although it wasn't explained why and didn't sound reasonable to me. Anyhow, do you have headers? How much louder did they make the car? I 'm already running a Dansk SS and it's louder than stock by more than a bit.

Edited September 18, 2007 by ghostrider300

[blinkwatt]

Thanks, I was aware of the O2 issue with the later models, I had read once elsewhere that aftermarket headers required frequent changes of exhaust gaskets although it wasn't explained why and didn't sound reasonable to me. Anyhow, do you have headers? How much louder did they make the car? I 'm already running a Dansk SS and it's louder than stock by more than a bit.

I don't have headers yet.....

I'm looking at 2 different(possibly 3) headers at the moment. The first are the imagine Auto headers. The 2nd headers are the ones on ebay,which look VERY similar to the imagine Auto ones.

The ebay ones are made by a company called Top Speed in Addison Texas. They basically take other companies designs and clone then. I have their Short Shift Kit(B & M clone with the shaft flip) and the exhaust(GHL clone,different mounting points) and I couldn't be happier.

Boggtown(member on here) just bought the ebay ones and will be installing them this week. He knows I've been looking into them for awhile but I only have 2 accounts of people with reviews(1 great,1bad),so he will be letting me know of the fitment and quality.

The 3rd set of headers I'm considering are by a company called TurboWerx,they are semi-new to the P-Car scene. They produced a Twin Turbo system for Boxsters. They claim +25hp w/ a K & N installed,and they have dyno charts to prove it. How they managed to get those types of gains I have no clue. You would think Gemballa , Fabspeed, evoms, or imagine Auto could come close to those types of gain but I have yet to see it.

[blinkwatt]

Thanks, I was aware of the O2 issue with the later models, I had read once elsewhere that aftermarket headers required frequent changes of exhaust gaskets although it wasn't explained why and didn't sound reasonable to me. Anyhow, do you have headers? How much louder did they make the car? I 'm already running a Dansk SS and it's louder than stock by more than a bit.

I don't have headers yet.....

I'm looking at 2 different(possibly 3) headers at the moment. The first are the imagine Auto headers. The 2nd headers are the ones on ebay,which look VERY similar to the imagine Auto ones.

The ebay ones are made by a company called Top Speed in Addison Texas. They basically take other companies designs and clone then. I have their Short Shift Kit(B & M clone with the shaft flip) and the exhaust(GHL clone,different mounting points) and I couldn't be happier.

Boggtown(member on here) just bought the ebay ones and will be installing them this week. He knows I've been looking into them for awhile but I only have 2 accounts of people with reviews(1 great,1bad),so he will be letting me know of the fitment and quality.

The 3rd set of headers I'm considering are by a company called TurboWerx,they are semi-new to the P-Car scene. They produced a Twin Turbo system for Boxsters. They claim +25hp w/ a K & N installed,and they have dyno charts to prove it. How they managed to get those types of gains I have no clue. You would think Gemballa , Fabspeed, evoms, or imagine Auto could come close to those types of gain but I have yet to see it.

[ghostrider300]

Thanks a lot Blinkwatt, I'd love to hear how Bogg makes out, I remember him from 986forum but I am no longer a member there. I couldn't find a comfortable nitch there. The headers I've seen on ebay are from maxspeed, then I've seen the ones that randall put on, did he ever comment on the noise level? The ebay headers are so cheap compared to say a Dansk set at about 1200.00 it makes me wonder about the fit & design quality. Keep me posted on anything else you find out, many thanks.

[boggtown]

Ive installed them, they fit just fine. They are the same ones everyone else sells. It makes the car a little throatier. Its a slight but good difference. When I open my bypass valves it sounds so much better though. Like a straight up whoosh growl instead of the undefined loudness before. So if I were to get a muffler itd sound awesome. My opinion is mufflers make the stock system louder, headers give the exhaust system tone/refinement. Both and youve got it going on, lol. I will get a muffler, i just wanted to start at the core (intake first, headers, then muffler is next). I am still hunting down a very slight leak, but Im not sure if its the headers yet. Im going to get a cover plate for my bypass valves and see if that fixes it. Im thinking the increase in velocity is making the leak louder to a noticeable level, where its the same as before but you couldnt hear it. If thats not it I will replace the gaskets and take the headers off to pressure test them. I will let ya know.

[ghostrider300]

Ive installed them, they fit just fine. They are the same ones everyone else sells. It makes the car a little throatier. Its a slight but good difference. When I open my bypass valves it sounds so much better though. Like a straight up whoosh growl instead of the undefined loudness before. So if I were to get a muffler itd sound awesome. My opinion is mufflers make the stock system louder, headers give the exhaust system tone/refinement. Both and youve got it going on, lol. I will get a muffler, i just wanted to start at the core (intake first, headers, then muffler is next). I am still hunting down a very slight leak, but Im not sure if its the headers yet. Im going to get a cover plate for my bypass valves and see if that fixes it. Im thinking the increase in velocity is making the leak louder to a noticeable level, where its the same as before but you couldnt hear it. If thats not it I will replace the gaskets and take the headers off to pressure test them. I will let ya know.

Thanks bogg, I can attest to the louder nature of the SS exhaust, I have the Dansk unit and I'm very happy with it. I am contemplating headers, my only other experience with them is on a motorcycle. On the twin, they made the bike exceptionally loud, on the fours the effect was more muted. I'd like the Boxster to sound mean, however, with the top up, it's already quite loud in the cabin compared to stock, I wouldn't want it to gain too many more db's but i'd be fine with a throatier sound. Do you think it added any power? The claims are all about 25hp, that sounds lofty to me...

[boggtown]

Expect 10. Expect nicer sound, not so much louder... Its much more... snarly...

[ghostrider300]

Expect 10. Expect nicer sound, not so much louder... Its much more... snarly...

It sounds like a good upgrade, do you think you feel any performance difference? What I've been doing is working on the car during winter in a makeshaft shop I have. This year, I was planning on putting pads & zimmerman cross drilled rotors on it, some aluminum pedals and headers. It already has a gt3 nose, screens, litronics and wheels. I'm always reading how the 2.5 is doggy, yet in actual driving you have to concentrate on not speeding...

[boggtown]

Like I said, I havent even gotten to 60 yet. I think it might have added power, but I will let you know more this weekend, im taking a trip down to springfield so I will be able to stretch my legs out a little...

[boggtown]

Well, dont know about the extra power, there probably is some but I cant tell, only way to find out is a dyno. But the sound alone is worth it.

[boggtown]

Just a little update, I passed my inspection for the year with the headers on.

[Stefan]

How would headers affect the state inspection requirements? The headers should have no significant effect on emissions.

[Stefan]

Ok, I discovered the answer to my own question. I didn't realize that there are preliminary cats built in to the headers on some cars. On those cars, replacing the headers with ones that don't have those cats could definitely affect emissions.