Expert advice needed on header and exhaust
been there done that
Joined: Jun 2002
Posts: 30,637
Likes: 0
From: 916
Originally Posted by 2001TypeR
thanks guys for the replies.
I still haven't received reply by e-mail from hytech or SMSP by the way.
Hey Snoopy, from the link of the header test, it seems that hytech production header is not that good and has bad ground clearance. Other than being production and not custom, what are the main differences between the production and the custom header from hytech?
I still haven't received reply by e-mail from hytech or SMSP by the way.
Hey Snoopy, from the link of the header test, it seems that hytech production header is not that good and has bad ground clearance. Other than being production and not custom, what are the main differences between the production and the custom header from hytech?
As for the SMSP headers, the cheaper kind seems nice but i would rather get the nice one with the all stainless steel.
At the SMSP site, I got confused though with the exhaust parts. I am not a pro at this stuff and now, i am a bit lost. There are many options for exhaust at SMSP. And for catalytic, there are 1 O2 and 2 O2 ?? I thought they only sell one exhaust kit that has everything included and together.
In terms of exhaust, just to make sure i am on the right track. I need everything to be 2.5 inches because that is the size of header end, right? More than that is no good, right?
After that, I need a 2.5 inches performance catalytic and a 2.5 pipe and muffler. Am i missing something? And you need a performance muffler, right?
Will the performance muffler eliminate some power? I know without catalytic, there is more power, right? But that would cause pollution.
So far, to be honest. I don't see enough difference in power gains to make me want to get hytech or SMSP header over the TODA racing one. Although the price difference between the Toda one and the SMSP header is like 150 US, but not sure if that will be worth it?
But i didn't make up my mind on the header yet. But as of the exhaust, since Toda doesn't make one, I think i would go with SMSP, or hytech or another custom one. I just want to learn more about the exhaust and the part i need for it.
Thread Starter
Registered User
Joined: Jun 2005
Posts: 14
Likes: 0
so header is no good with turbo, but i guess exhaust will be good, right?
In terms of going turbo or SC, i am reading up on that, but still not clear on the subject. I read that with higher RPM cars like Type R, it is better to go with turbo, is that true? What do you guys think is better for Type R's? Turbo or SC?
I still haven't heard from dave from SMSP, but will send him another e-mail.
In terms of comparing SMSP and hytech headers and exhausts, are there major differences in power gains and quality?
About hytech headers, can someone clarify to me what anti-reversion chambers mean and do? This is the main difference between production and custom hytech headers.
Also for the hytech full exhaust with Renault cat, john told me in the e-mail that it is $1050. It looks nice in the picture, but i want to ask your guys' opinion. Is this a nice exhaust system compared to the best ones outhere? And how is the price compared to the competition?
About the header, I am happy that i am eliminating certain choices so it is getting easier to make a choice. I think that Toda will be better than hytech and SMSP production headers, and i hope i am right. So now, I am trying to choose between Toda, SMSP and hytech headers.
If i decide to go with the Toda header, will it still be good and fit properly with hytech full exhaust? Or are measurements different? Or not recommended?
Thanks again for all the replies and help guys
2001TypeR
In terms of going turbo or SC, i am reading up on that, but still not clear on the subject. I read that with higher RPM cars like Type R, it is better to go with turbo, is that true? What do you guys think is better for Type R's? Turbo or SC?
I still haven't heard from dave from SMSP, but will send him another e-mail.
In terms of comparing SMSP and hytech headers and exhausts, are there major differences in power gains and quality?
About hytech headers, can someone clarify to me what anti-reversion chambers mean and do? This is the main difference between production and custom hytech headers.
Also for the hytech full exhaust with Renault cat, john told me in the e-mail that it is $1050. It looks nice in the picture, but i want to ask your guys' opinion. Is this a nice exhaust system compared to the best ones outhere? And how is the price compared to the competition?
About the header, I am happy that i am eliminating certain choices so it is getting easier to make a choice. I think that Toda will be better than hytech and SMSP production headers, and i hope i am right. So now, I am trying to choose between Toda, SMSP and hytech headers.
If i decide to go with the Toda header, will it still be good and fit properly with hytech full exhaust? Or are measurements different? Or not recommended?
Thanks again for all the replies and help guys
2001TypeR
Senior Member
Joined: Oct 2002
Posts: 419
Likes: 0
From: USA
Seems like you don't have your plans laid out yet, Take your time and decide what your going to do to the caR first. Once you have that, report back and get some clear answers for your clear questions.
exhaust will determine many things for your caR.
exhaust will determine many things for your caR.
Registered User
Joined: Apr 2003
Posts: 10
Likes: 0
Just a few notes
For your ITR you could use 4 different SMSP headers.
The 1 piece 4-2-1 mild steel (recommended to be coated) however you can't use the ITR tranny/block brace but ground clearance is excellent
Multi piece "GSR" 4-2-1 style header in 100% stainless however you can't use the ITR tranny/block brace but ground clearance is excellent
Multi piece ITR 4-2-1 style header in 100% stainless and you can retain the tranny/block brace but ground clearance isn't as good as the above 2.
1 Piece 4-1 100% stainless header (available late summer)
All the above will require at least a custom length cat or test pipe, but I don't recommend test pipes for the street.
My exhausts come in kits and therefore require welding during installation. My website has a menu of items to choose from to customize the exhaust to your liking.
Just FYI, the A/F tuning done in the above linked header test was not extensive and the A/F ratios were not linear as one would believe from reading the write up.
For example here is the link to the A/F curve versus torque for my 1 piece 4-2-1 mild steel header.
http://www.imagestation.com/picture/...a/f3fa8552.jpg
BTW, I just had a customer who recently sold his Toda header and got a 1 piece mild steel header.
The 1 piece 4-2-1 mild steel (recommended to be coated) however you can't use the ITR tranny/block brace but ground clearance is excellent
Multi piece "GSR" 4-2-1 style header in 100% stainless however you can't use the ITR tranny/block brace but ground clearance is excellent
Multi piece ITR 4-2-1 style header in 100% stainless and you can retain the tranny/block brace but ground clearance isn't as good as the above 2.
1 Piece 4-1 100% stainless header (available late summer)
All the above will require at least a custom length cat or test pipe, but I don't recommend test pipes for the street.
My exhausts come in kits and therefore require welding during installation. My website has a menu of items to choose from to customize the exhaust to your liking.
Just FYI, the A/F tuning done in the above linked header test was not extensive and the A/F ratios were not linear as one would believe from reading the write up.
For example here is the link to the A/F curve versus torque for my 1 piece 4-2-1 mild steel header.
http://www.imagestation.com/picture/...a/f3fa8552.jpg
BTW, I just had a customer who recently sold his Toda header and got a 1 piece mild steel header.
been there done that
Joined: Jun 2002
Posts: 30,637
Likes: 0
From: 916
Originally Posted by 2001TypeR
In terms of comparing SMSP and hytech headers and exhausts, are there major differences in power gains and quality?
About hytech headers, can someone clarify to me what anti-reversion chambers mean and do? This is the main difference between production and custom hytech headers.
REVERSION is the secondary pressure wave that travels back up the primary pipes and enters into the cylinder on valve overlap. As this pressure wave travels back up the pipe, it brings with it all the residual gases still left in the pipe. This is what contaminates the fresh intake charge. Enter in stepped headers and ANTI-REVERSION chambers, placed at strategic locations in the primary pipes. These methods are employed to tune the arrival of the exhaust wave and to diminish the effects of the high pressure in the pipes. The results are higher volumetric efficiency and more power.
