2.5 conversion header

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Castro
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Joined: Wed Feb 11, 2015 9:01 am

2.5 conversion header

Post by Castro »

Going thru previous post here and at M.net I saw mentions of a 1.8 shorty header and a 1.8 PPE header... What's the status of these? Got my 2.5 on a engine stand getting it ready to do the swap and would need one of this to complete my conversion.
Brian
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Re: 2.5 conversion header

Post by Brian »

Both complete...and likely shipping in June
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
Castro
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Joined: Wed Feb 11, 2015 9:01 am

Re: 2.5 conversion header

Post by Castro »

Great! When will you be taking pre-orders?
Brian
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Re: 2.5 conversion header

Post by Brian »

Soon, likely the 1.8 shorty header will start taking orders by middle of this month, and hopefully 1.8 long tube by end of month.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
ourly
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Re: 2.5 conversion header

Post by ourly »

Brian,
What are the benefits of the 1.8 long tube?
Rick
olgzr
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Re: 2.5 conversion header

Post by olgzr »

Will the 1.8 shorty work with any of your mid pipes?
Brian
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Re: 2.5 conversion header

Post by Brian »

Yes, 1.8 shorty is a shorty because it works with standard flange position. Thus, it works with our midpipe.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
jamaican_tuner
Posts: 17
Joined: Wed Feb 04, 2015 11:00 am
Location: South Florida

Re: 2.5 conversion header

Post by jamaican_tuner »

How will the 1.8 work on the 2.0? Could one run the 1.8 shorty with same or better results than GWR max power header while waiting to secure a 2.5 swap?
Brian
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Re: 2.5 conversion header

Post by Brian »

Bigger is NOT always better, you want efficient FAST exit of exhaust gasses, not stalling of exhaust gas speeds because pipe size is too big. I have tested every size pipe you can put on NC motors...up through 2 inch header primaries (our NC Light project used 2 inch header primaries MANY YEARS before anything bigger than 1.6 was on the market). In our testing even 1.75 is a bit big for normally aspirated 2.0 that drives in the real world because the resulting torque peak shifts higher up the rpm range. That's why both our shorty header and long tube are 1.6 inch, for best gains start to finish for 2.0 customers using their cars on public streets and highways.

We could have used any size but decided not to chase peak 'advertising numbers' which put emphasis on the peak of rpm range like some of our competitors push without regard for gutting the low end. For a pure race car shifting torque peak way up the rpm band is not terrible, we did it intentionally on our NC Light project because the focus of the power band was the top end where a track car lives, but for a Miata that drives the real world it makes the car into more of a dog from stoplights, and in freeway passing unless you do lots of downshifts to pass. Unless you want the most lowly minivan dusting you off from stoplights don't shift the power band higher.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
jamaican_tuner
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Location: South Florida

Re: 2.5 conversion header

Post by jamaican_tuner »

Sorry should have clarified.

Car is a track car. Currently running a modified header desiged to pass tech for SCCA T4 but since my wheel to wheel goals may be changing and I may leave this car as an HPDE car I am looking to improve the current power curve. 2.5 is something I am considering down the line.

Car is a 5 speed and tires are 225 45 17 and I need more oomph in 2nd and 3rd to get out of the corners (especially since the longest straight is from a chicane that has you exiting in 3rd gear).

Was hoping to buy a header that would benefit me now with the 2.0 and still work well on the 2.5.
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