Peter10

First post here after scouring the forums for the past couple years thinking/planning out my 1.8 swap and turbo build for my 1.6 1992. I will likely be running an EFR6258 once I get the funds together, and will be shooting for 300-375whp depending on how everything pans out, not hard set on hitting a certain power level it will make what it makes. I want the engine internals overbuilt, and don't want to cut corners but am still on a budget after just graduating college, paying off student loans, etc. Car will be a summer/weekend car and see autocross/HDPE track day events.

Long story short, I got a 1994 parts car that had a dash fire and had sat for 10 years. Engine still turns over by a 1/2" ratchet, I pulled it and am currently stripping it down to bring to the machine shop to get it prepped for forged internals. (Manley rods, Wiseco 8.5:1 CR .5 or 1mm over pistons, ARP hardware, boundary stage 2 oil pump etc etc) I was going to keep it simple just refresh the head for now (probably with stiffer valve springs) and run around 250whp for a couple years and then swap to a VVT head and turn up the boost after I work on my driving skills. I'll be controlling with Ms3Pro PNP.

However, I just came across a running when pulled 03 VVT full engine assembly for a good price nearby. I am now wondering if I should pick this up to swap the VVT head (along with intake and stuff) over to my 94 shortblock that I'm building, as well as the oil pan, pickup, and main bearing support plate because why not. I'm thinking better flow, VVT control improving power curve, and solid lifters in the 03 head vs my BP05 hydraulic lifters would also be an improvement.

Before I dive into a second engine what do people have for input/big roadblocks. Is this doable? What am I wrong about or missing? My biggest challenges from what I can foresee are oil supply for VVT and crank sensor/trigger wheel stuff. I'm planning on COP conversion for ignition. Open to any and all advice!

Dr.Sep

Yes. VVT > BP05 all day and why do the work twice

300 is doable for sure, 375 is on the high end in my experince with the 6258 (probably not possible on pump gas, E85 yes) but YMMV

Peter10

That's what I'm thinking, I'm fine with upgrading something I left stock later but not trying to upgrade an upgrade if that makes sense.

And yeah, I'm hoping by that time E85 is more readily available in my area, I'm planning on making all the fuel system compatible.

Icedawg

Sounds like a fine idea to me. Better flowing head, and VVT, and a spare block.
The extra support plate that doubles as the windage tray needs tapped holes to bolt to, though.
And if your PnP is for a 94, does it have the functional components to run the VVT?

Peter10

Yeah I would hopefully be able to assemble an extra "stock" long block after all is said and done and sell to recoup some costs once I'm confident in mine running well.

Thats a very good point, you're referring to the threaded holes in the main caps right? I was planning to reuse my 94 main caps as I don't think mazworks billet mains are really needed and that 500 could be spent elsewhere. I'll have to check that my mains have threaded holes, I think they do but can anyone confirm?

As far as I've read my MS3Pro will be VVT compatible regardless of the chassis year (92) can anyone confirm or deny that as well? ECU and sensor stuff is not my strongest suit.

Icedawg

If it is an MS3Pro, not a year specific plug n play, then for sure it has the ability.
I had mistakenly thought I read you had a 94 PnP unit, which may or may not be able to run VVT

Peter10

Ok thanks, according to their website under "Miata 9093 MS3Pro PnP Advanced Feature Set (Included!)" it lists VVT support if swapping to a later VVT motor. I assume I'll have to run a few wires to connect it but as long as the ECU supports it I think I'm in the clear. Still trying to figure out some of the cam/crank angle and position sensor differences which I think is going to be the biggest headache.

DNMakinson

iTrader: (3)

There is an entire thread dedicated to putting VVT engine in NA Miata. Should assuage all of your fears.

Use this query in Google

Peter10

Thank you, yes I've been looking through that thread. My concern was more if there's anything I'm missing in terms of differences between early 1.8 block and 03 1.8 "VVT block" that would make the early 1.8 shortblock I'm building right now with forged internals unable to swap a VVT head onto. Seems like early 1.8 head gasket and coolant reroute is the way to go for the head swap.