"Performance" headers?
29 June 2014, 10:39 AM
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"Performance" headers?
There's been a bit of talk around about after market headers and a couple of cheaper versions which seem to actually cost power rather than encourage it.
We were asked to fit a set recently which we rejected on inspection out of hand. These have a collector which uses the four pipes sharply cut off, with a collar directly opposite. The collar has a quarter circle section, with a 90 degree edge presented to the gas flow. I'd describe this design as disastrous!
We tend to stick to the RCM version, which has a much smoother outlet. I guess you expect to get what you pay for.
We were asked to fit a set recently which we rejected on inspection out of hand. These have a collector which uses the four pipes sharply cut off, with a collar directly opposite. The collar has a quarter circle section, with a 90 degree edge presented to the gas flow. I'd describe this design as disastrous!
We tend to stick to the RCM version, which has a much smoother outlet. I guess you expect to get what you pay for.
29 June 2014, 11:22 AM
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Is the first picture not exhaust, though?
I understand you would want them to be cut and welded so that it forms a more or less rounded section when entering, like I saw yesterday on the Aston Martins in Prodrive, but from what I understand, this is not countering the gas flow, but blowing it out, and technically, the only thing there might be turbulence, as the gas is not hitting the 90 degree edge.
Or am I getting it wrong and the flange is actually smaller in diameter than the pipe where the 4 header pipes enter? Or is it a single piece of a pipe that has been compressed so as to present the gas flow with compression?
Is it a genuine TOYOSPORTS, though?
I understand you would want them to be cut and welded so that it forms a more or less rounded section when entering, like I saw yesterday on the Aston Martins in Prodrive, but from what I understand, this is not countering the gas flow, but blowing it out, and technically, the only thing there might be turbulence, as the gas is not hitting the 90 degree edge.
Or am I getting it wrong and the flange is actually smaller in diameter than the pipe where the 4 header pipes enter? Or is it a single piece of a pipe that has been compressed so as to present the gas flow with compression?
Is it a genuine TOYOSPORTS, though?
Last edited by netbeast; 29 June 2014 at 11:28 AM.
29 June 2014, 11:39 AM
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29 June 2014, 11:56 AM
#9
In fairness in my younger days I had toyosports exhaust manifolds on an mx5 and Saxo vts I had . . Then again they arnt performance vehicles . . And those were the days when I only worked part time!
29 June 2014, 04:14 PM
#16
Toyosport are alibaba specials...similar to Japspeed....the factories in China stamp your brand name on for free 
The way people can 'trust' a brand because they come up with a website and some marketing but then moan at the counterfeit HKS valves (all made in the same factories folks!) never ceases to amaze me..
The way people can 'trust' a brand because they come up with a website and some marketing but then moan at the counterfeit HKS valves (all made in the same factories folks!) never ceases to amaze me..
Last edited by Trinity; 29 June 2014 at 04:16 PM.
29 June 2014, 09:44 PM
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29 June 2014, 09:45 PM
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29 June 2014, 09:48 PM
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Is the first picture not exhaust, though?
I understand you would want them to be cut and welded so that it forms a more or less rounded section when entering, like I saw yesterday on the Aston Martins in Prodrive, but from what I understand, this is not countering the gas flow, but blowing it out, and technically, the only thing there might be turbulence, as the gas is not hitting the 90 degree edge.
Or am I getting it wrong and the flange is actually smaller in diameter than the pipe where the 4 header pipes enter? Or is it a single piece of a pipe that has been compressed so as to present the gas flow with compression?
Is it a genuine TOYOSPORTS, though?
I understand you would want them to be cut and welded so that it forms a more or less rounded section when entering, like I saw yesterday on the Aston Martins in Prodrive, but from what I understand, this is not countering the gas flow, but blowing it out, and technically, the only thing there might be turbulence, as the gas is not hitting the 90 degree edge.
Or am I getting it wrong and the flange is actually smaller in diameter than the pipe where the 4 header pipes enter? Or is it a single piece of a pipe that has been compressed so as to present the gas flow with compression?
Is it a genuine TOYOSPORTS, though?
I've no idea where it comes from, just that it's cack.
30 June 2014, 08:31 AM
#25
Would you agree Alan ?
Last edited by Silver Scooby Sport; 30 June 2014 at 08:32 AM.
30 June 2014, 08:40 AM
#27
30 June 2014, 09:43 AM
#30
I'm now on my second set of equal length headers . . First set was toyosports which gave a few problems in terms of fit . . Now have a set I managed to get from rcm (insure of the brand but 100 times better) .
Would be interesting to stick the toyos back on and get it rr'd to see the result . .
Would be interesting to stick the toyos back on and get it rr'd to see the result . .