WTB: Miata head ASAP

[323GT-R]

You can see here on the original BP01 head, there's a mounting bolt for the dizzy just below it, which is used for the CAS on the Miata. The BP4W head doesn't have this mounting, since the 99 Miata uses a CAS on the cam pulley and a crank angle sensor.

[323GT-R]

Ok, what do you need to see in a pic to prove it's a 99 head?
You tell me what you want to see, and I'll have the pic posted by tomorrow.

[D323]

might be different overseas then. Really odd.

[323GT-R]

The only difference I could find was that the UK spec cars have a fuel pressure reg on the rail, whereas the US market miata has a wierd set up with no fuel return and the regulator in the pump. You have to use the 99 fuel rail with the 99 head, or mod your early rail to fit - I used the 99 rail. You also have to modify the intake manifold to fit (drill new holes in it to relocate it over the ports). The exhaust side bolts straight on. Make a blanking plate for the miata thermostat and it's job done. A simple conversion.

[D323]

Yeah after reading more in depth on the solo site, they say port, as in the intake port is different... they then go on to mention that you would need to use the miata intake, (which wont work for our cars as previously determined in other threads) but since you mentioned it you can mods yours to fit. Did you have any issues getting the ports to match up?

The 99-00 head will interchange onto the earlier 1.8 block if you also determine how to control the variable intake valve in the '99 manifold (VICS systems, probable a rpm activated selenoid will do it) as well as retrofit a cam angle sensor for the earlier ECU (the cam drive is still there so it just slaps on). You will also need a 99+ intake manifold.

[323GT-R]

No, the ports are the same, just raised up the head. If you look at the pic posted earlier with the gasket, basically the ports are the same shape but about 10mm higher up the head. The studs stayed in the same place though, so I just redrilled the holes in the manifold to raise it by 10mm. There is plenty of meat on the flanges on the GTR manifold, so this wasn't a problem, although I had a spare one just in case...

You could possibly still keep the original dizzy, but you would only have one stud to mount it to the head, or you'd have to make a bracket. I have standalone ECU, so I just switched to wasted spark with the Miata ignition coils at the same time as fitting the head.

[TheMAN]

it's not the "same" if drilling and cutting is involved

drilling/cutting != bolt on/plug and pray

[323GT-R]

I had to drill a few holes to mount the roll cage too, I'm praying it doesn't fall out Some mods need a little more work than others, drilling a few holes and making a blanking plate for the thermostat is hardly much work. Wait till you see my Evo gearbox conversion, lol!!! Come to think of it, I had to drill a few more holes to get the 4 pot brakes on there, maybe that's a risk too far...

One thing I have always believed in is to use the best base components avialble when building an engine. The BP4W head and cams are a step up from the BP01 head, so it made sense to use that as the basis. I gave it a mild port job whilst it was off too, and tweaked the cam timing a little with the adjustable pulleys. The best part is getting rid of those damned hydraulic tappets though!

[Intruder]

There is plenty of meat on the flanges on the GTR manifold, so this wasn't a problem, although I had a spare one just in case...

It just so happens that I have a BP4W head in my garage, and a BP05 intake manifold. I looked to see if I could drill holes in the manifold to make it fit the BP4W head, but it doesn't seem possible.

Do you mean that the GTR intake manifold really has more meat than a regular intake manifold?

Do you by chance have a pic of your manifold after you drilled the holes in it? Or a pic of a stock GTR manifold's flange?

[FE3-323]

id love a bp4w head on mine is there an advantage to using the miata ignition system?? VS. the distributer system?

[pigeon]

id love a bp4w head on mine is there an advantage to using the miata ignition system?? VS. the distributer system?

never change ur cap/rotor again!

[D323]

never change ur cap/rotor again!

I was gonna say... alot of the euro GTR guys swap to a ditsyless system b/c it tends to be a weak point.

Suckie thing about the miata system is that you'd have to go standalone, or use the miata harness to control it from what I have read.

[jacobrussell]

id love a bp4w head on mine is there an advantage to using the miata ignition system?? VS. the distributer system?

DUDE ARE YOU SERIOUS?? WASTED SPARK IS THE ****

EVERY ONE SHOULD CONVERT AND BTW IF YOU DIDNT KNOW YOU DONT HAVE TO GET RID OF YOUR BP ECU TO RUN IT THEY ALSO HAVE A MEGAJOLT THAT WILL JUST RUN THE EDIS!!

wasted spark helps clear the other cylinder on its on its non firing stroke both 1-2 cylinders fire at the same time and 2-3 at the same time!!!

[FE3-323]

good info, what exactly is needed to fully convert to the miata ignition system

[Jho]

good info, what exactly is needed to fully convert to the miata ignition system

He used EDIS, electronic distributorless ignition system, from a ford escort.