1.6 Head rebuild seeking the consul of wise men and women

[Infedora]

First off, I'm aware of all the mechanics of doing it and that it's not a necessarily sensible choice. My application is a naturally aspirated 1.6 with a standalone ecu, Randall intake, AFM free, feeding into a full FM 2.5 exhaust.

My question is to those who have done it or are intimately familiar with rebuilds, what modifications produced the best returns for the cost?

Examples:

Polish and port
Three angle grind
Deshroud
Supertech oversize valves
Etc, etc

I do plan on skimming at least .030.


And because lately I've been hanging out with the wrong crowd I might just go ITB to troll the Miata turbo kids I hang out with.

I look forward to your thoughtful responses. (No I'm not doing a 1.8 swap)

[MiataQuest]

Myself I would not spend the $$ on custom head work and ITB's. Just add a supercharger for the same money with a better return on horsepower and torque.

[Infedora]

MiataQuest, I agree completely, but I'm concluding my goals given where I drive and what I'm looking for are more visceral than just torque/power. If I blew a rod tomorrow, it'd be a 2001+ block, 1990-2000 manifold in a heartbeat.

[kung fu jesus]

Skim + new valve seats. The rest is pretty useless individually and without cams. By the time you get done with a quality reworked head, a junk yard NB engine is still going to be better for far less money.

[Infedora]

So little 1.6 love in this world.

[kung fu jesus]

You asked, I'm giving you anecdotal and factual truth.

Also keep in mind, a lot of B6 parts are starting to be phased out.

[Infedora]

Upside to 1.6 falling from favor, discount pricing! But on the topic of anecdotal and factual truth, this is a forum. ��

[DarylSibcy]

So little 1.6 love in this world.

Plenty of love. Just none when the topic of "power" comes up in a conversation about a miata. If you stay with a 1.8 you could use the newer Skunk2 manifold too, always a thought.

I've had head work done, skimmed and ported. New valve seats, back cut valves but not oversized. Jenvey ITBs with a Maxim Works header with a MSII ECU handling the AFR :winky: Drives well, produces strong linear power, way above what a stock 1.8 would push. I don't regret it, I'm happy with 160bhp~ :D If you want more than that without sacrificing the torque the engine already doesn't have, a 1.8 with similar work will get you 180bhp~ - and you always have the option of FM's Stroker kit, if you're wanting to hit the 200bhp mark. Skunk2 currently have no manifold option for the 1.6, which is a shame given the amazing value for money it carries, ITBs aren't cheap, because they're complicated. :lol:

If you're handy and willing to butcher a 1.8 Skunk manifold you could probably adapt it to fit, it's a long shot though with no guides to follow, I've considered trying myself but seeing as I already have ITBs it'd be a waste to sell them for the price the Skunk would cost. I can't imagine USED ITB's being in high demand. :shrug:

Phasing out 1.6 parts is purely because of demand though. If you want a "performance" engine, there's no replacement for displacement.

[kung fu jesus]

OP can hit 160 with the ECU he has, an NB engine + bolt ons and ethanol.

[DarylSibcy]

OP can hit 160 with the ECU he has, an NB engine + bolt ons and ethanol.

Agreed! +1

Ethanol isn't something I'd use myself, too inconvenient where I live. A good NB engine with a BP5A cam would also do. Even more with bolt ons too!

I don't regret building up my 1.6. But I will admit the car would be faster and have better driveability with the same mods done to a 1.8 at no extra cost.... Considering the cost of buying a miata with a 1.6 or 1.8 is practically negligible most people go the 1.8 route, because it's more sensible. I am however too far gone with my 1.6 to simply lose out financially to move to a 1.8. Also, I am not sensible :lol: