Oversized TB on N/A MX5

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AB7
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Oversized TB on N/A MX5

Postby AB7 » Tue Mar 10, 2009 6:20 pm

Hi Guys,

Im wondering if anyone had done oversized TB on their N/A MX5?
Is it worth doing?

grump
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Oversized TB on N/A MX5

Postby grump » Tue Mar 10, 2009 6:43 pm

AB7, its probably worth doing only if you have a microtech, megasquirt , etc. and can retune to take advantage of the extra air fuel mixture. I'm not sure the factory ECU can cope with the change.
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Oversized TB on N/A MX5

Postby Fatty » Tue Mar 10, 2009 6:47 pm

even then i think it would only be worth doing after you have done all the other breathing mods (intake, headers,headwork, higher rev limiter etc). i doubt the tb is in any way restrictive on a reasonably stock engine. on a fully worked engine maybe, but not on a stocky i reckon. just a guess tho, could be wrong.

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Oversized TB on N/A MX5

Postby grump » Tue Mar 10, 2009 6:50 pm

If it is an NA6, and you have an after market ECU the best advantage would be to put a variable TPS on it
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stevesports
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Oversized TB on N/A MX5

Postby stevesports » Tue Mar 10, 2009 7:22 pm

he has a NB8B with headers,exhaust and intake mods, with a programmable ECU (Hydra nemesis i think?)

so i guess it might work? otherwise a higher rev limit i think would gain a few kw's

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Oversized TB on N/A MX5

Postby grump » Tue Mar 10, 2009 7:47 pm

the only problem is that higher revs won't solve the problem, If you look at all the dyno results, the maximum torque is reached well before maximum revs are.
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AB7
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Oversized TB on N/A MX5

Postby AB7 » Tue Mar 10, 2009 7:57 pm

Like Steve said, I got headers, exhaust, intake and stand alone ecu (hydra) with MAP sensor. Since I ditched the MAF, I'm wondering if it's worth it to enlarged my tb. I need to retune my car again soon, hence maybe it's better to do it all in one. Had a chat with peter about this, and cams is out if the questions since vvt cans with lasher caps ( which has to be replaced in vvt engine) will cost $1.2 k excluding labour.

I'm wondering if anyone has done it? Even if it's worth it since my head is practically stock

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Oversized TB on N/A MX5

Postby grump » Tue Mar 10, 2009 8:04 pm

so do you have an NA or a NB8B?
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Hammer
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Oversized TB on N/A MX5

Postby Hammer » Tue Mar 10, 2009 8:10 pm

grump wrote:so do you have an NA or a NB8B?


I think when he wrote N/A, he meant Naturally Aspirated.
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grump
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Oversized TB on N/A MX5

Postby grump » Tue Mar 10, 2009 8:12 pm

Hammer wrote:
grump wrote:so do you have an NA or a NB8B?


I think when he wrote N/A, he meant Naturally Aspirated.

thanks Hammer it all makes sense now. BTW how is the clubman going
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Oversized TB on N/A MX5

Postby Hammer » Tue Mar 10, 2009 8:38 pm

It's going great. Very happy with it. Thanks for asking :D
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