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MX5 1.6 vs 1.8
FFMan - 14/8/21 at 07:59 AM

So I have an NB 1.6 in a track car. I'm guessing its the 110bhp being NB ?

It's on good tyres and fun to fling around but lacks some zip. I want to give it some more power but as it has nice balance at the moment I'm think around the 150bhp mark will be fine. It's only 520kg after all, and have other faster toys, this is just for simple agile fun that I share with my wife (and soon son no doubt).

I was originally looking at FI but its more complexity and cost than I really want, as I need to keep it reliable when driven hard.

So i was thinking of dropping in a 1.8 but there seems to be a lot of nay sayers about that, and how much nicer the 1.6 is to drive. I had read i think that keeping the 1.6 flywheel keeps some of rev ability.

The hop up from 110bhp to 140bhp is a 30bhp kick which with some following mods should make my 150 target with no drama and seems like a cost effective route, especially as in the first instance I can run the 1.6 ecu.

I intended to go non-vvt as that opens the door to racier cams later on.

Just interested in peoples views - thanks


PorkChop - 14/8/21 at 11:59 AM

If 150bhp is the target, just stick a VVT in it - that will be the easiest and most cost effective way of getting it. VVTs with the ECUs are 300 ish, maybe a bit more. From experience of driving a 1.6 NB then the same car after a VVT swap, it's every bit as nice to drive. A lot of the conversations are around early 1.6s compared to the mk1 1.8.

If you intend going to a cammed or FI engine, then you'll be changing the ECU to do that, so there's nothing stopping you from deleting the VVT then if wanted / needed.


FFMan - 14/8/21 at 01:38 PM

quote:

If you intend going to a cammed or FI engine, then you'll be changing the ECU to do that, so there's nothing stopping you from deleting the VVT then if wanted / needed.


thanks - i was under the impression the cams were different non-vvt to vvt and that there weren't any interesting cams for the vvt setup ? For this reason i was intending non-vvt as a base but i could be wrong.


PorkChop - 14/8/21 at 03:39 PM

Cat Cams do upgraded VVT cams e.g. https://bofiracing.co.uk/engine-pa rts/camshafts/cat-cams-sport-270-270-camshafts-for-mazda-mx-5-1-8-vvt-bp-z3/

You could always change to a non VVT head if the cams you want won't fit.

[Edited on 14/8/21 by PorkChop]