NA8 vs NB8

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Myata
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NA8 vs NB8

Postby Myata » Fri Dec 30, 2011 3:35 pm

Hey all

Am going to convert my NA6 to a BP as soon as i find one available

Are there any major differnces between NA8 and NB8?

Does the NB8 need the NB gearbox etc?

Planning on turboing the BP mid next year, so is one better then the other for forced induction?

Did a bit of searching, but couldn't find an answer

Cheers, Jared
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Re: NA8 vs NB8

Postby project.r.racing » Fri Dec 30, 2011 4:03 pm

massive differences. and 2 versions of the NB BP motor. google didn't turn up anything?

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Re: NA8 vs NB8

Postby NitroDann » Fri Dec 30, 2011 5:08 pm

If its street dríven go a 99+ motor and ms3.

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Re: NA8 vs NB8

Postby NitroDann » Fri Dec 30, 2011 5:11 pm

Sorry I should specify, I meant a VVT motor, so 01+.

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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

Myata
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Re: NA8 vs NB8

Postby Myata » Fri Dec 30, 2011 5:18 pm

Google didn't give me anything decent.

What's involved in a VVT conversion from NA6?

Is going to be street dríven, and then a snail put on mid next year.
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Re: NA8 vs NB8

Postby geofiz » Fri Dec 30, 2011 5:30 pm

NitroDann wrote:Sorry I should specify, I meant a VVT motor, so 01+.

Dann


Why VVT overs VICS?


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Re: NA8 vs NB8

Postby NitroDann » Fri Dec 30, 2011 5:44 pm

Spooling a turbo.

Vics helps increase port velocity at low rpm which helps a little but restricts total flow at high rpm.

VVT give much more volumetric efficiency at lower rpm, and more exhaust port timing spooling a turbo hard and fast.

Also, an NB motor has solid lifters, making cam swaps much better.

And 99+ heads flow much better than 94-97 heads.

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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

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Re: NA8 vs NB8

Postby Myata » Fri Dec 30, 2011 6:17 pm

Ohk. So how much is involved in a VVT transplant?
cheers
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Re: NA8 vs NB8

Postby bensale » Fri Dec 30, 2011 9:03 pm

Lightyear has just done a complete transfer of all the running gear from an nb8b (vvt 1.8) into an na6. Saw it yesterday, seemed to fit well !! I like the idea of a Frankenfive :)

Aren't the vvt engines more difficult to turbo though? I vaguely remember it being a complication for the SP's development.

NA & NB gear boxes, diffs etc are all interchangeable too.
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Re: NA8 vs NB8

Postby NitroDann » Fri Dec 30, 2011 9:25 pm

VVTs have 10:1 compression, almost high enough for an E85 turbo engine at 15psi. And they have VVT which a lot of ecu's have trouble effectively controlling.

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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

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bensale
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Re: NA8 vs NB8

Postby bensale » Fri Dec 30, 2011 10:19 pm

Makes sense. Cheers for the explanation.
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Myata
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Re: NA8 vs NB8

Postby Myata » Mon Jan 02, 2012 11:03 pm

OK so the NB VVT motor is the way to go then. do they bolt up to the NA6 gearbox? or worth doing complete swap (gearbox diff tailshaft etc)?
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Re: NA8 vs NB8

Postby Myata » Mon Jan 02, 2012 11:04 pm

Also, does that mean custom crossmembers etc?
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Re: NA8 vs NB8

Postby NitroDann » Mon Jan 02, 2012 11:09 pm

Straight bolt in. But the diff wont survive a week and the gearbox will make it 6 months. Do the full swap. Neither of those time frames are exaggerations.

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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

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Re: NA8 vs NB8

Postby Myata » Mon Jan 02, 2012 11:14 pm

Sweet as

NB VVT engine, gearbox, diff and tailshaft.
Does that then require NB C.Vs and hubs, brakes etc?
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