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NA8 vs NB8

Posted: Fri Dec 30, 2011 3:35 pm
by Myata
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

Re: NA8 vs NB8

Posted: Fri Dec 30, 2011 4:03 pm
by project.r.racing
massive differences. and 2 versions of the NB BP motor. google didn't turn up anything?

Re: NA8 vs NB8

Posted: Fri Dec 30, 2011 5:08 pm
by NitroDann
If its street dríven go a 99+ motor and ms3.

Dann

Re: NA8 vs NB8

Posted: Fri Dec 30, 2011 5:11 pm
by NitroDann
Sorry I should specify, I meant a VVT motor, so 01+.

Dann

Re: NA8 vs NB8

Posted: Fri Dec 30, 2011 5:18 pm
by Myata
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.

Re: NA8 vs NB8

Posted: Fri Dec 30, 2011 5:30 pm
by geofiz
NitroDann wrote:Sorry I should specify, I meant a VVT motor, so 01+.

Dann


Why VVT overs VICS?

Re: NA8 vs NB8

Posted: Fri Dec 30, 2011 5:44 pm
by NitroDann
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.

Dann

Re: NA8 vs NB8

Posted: Fri Dec 30, 2011 6:17 pm
by Myata
Ohk. So how much is involved in a VVT transplant?
cheers

Re: NA8 vs NB8

Posted: Fri Dec 30, 2011 9:03 pm
by bensale
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.

Re: NA8 vs NB8

Posted: Fri Dec 30, 2011 9:25 pm
by NitroDann
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.

Dann

Re: NA8 vs NB8

Posted: Fri Dec 30, 2011 10:19 pm
by bensale
Makes sense. Cheers for the explanation.

Re: NA8 vs NB8

Posted: Mon Jan 02, 2012 11:03 pm
by Myata
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)?

Re: NA8 vs NB8

Posted: Mon Jan 02, 2012 11:04 pm
by Myata
Also, does that mean custom crossmembers etc?

Re: NA8 vs NB8

Posted: Mon Jan 02, 2012 11:09 pm
by NitroDann
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.

Dann

Re: NA8 vs NB8

Posted: Mon Jan 02, 2012 11:14 pm
by Myata
Sweet as

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