01 VVT Head on 94 block???
 

I know that the 99-00 head works on the earlier 1.8L engine but what about the 01+ VVT head? Also would my MS be able to use one if its outputs to control the VVT?

the only ECUs that control the VVT that I know of are the hydra and the freedom. The hydra is $2k and the freedom is in japaneese, so it makes things difficult.

In fairness, no one has tried to make the ms run vvt either, to my knowledge. Obviously it doesn't do it out of the box or without custom work like the previously mentioned solutions.

As I understand it VVT requires a squarewave to drive the solenoid as its constantly variable not just on or off. One option would be to use the EBC driver and PWM map but it hasn't been done yet and I'm not sure how you could get the MS to monitor the cam angle and contantly adjust in a closed loop (it has to do this as it modulates oil pressure to move the cam and the oil pressure will change as you rev the engine). Maybe a second MS1 running the solenoid from the injector driver so you can have a fully mappable cam advance?

Rev has made a separate controller for his VVT perhaps he can chime in?

The other option is to lock the cam in the 0 degrees position or swap in a static cam and remove all the VVT bullshit. Unfortunately you cannot just leave the VVT unplugged as the cam will then go fully retarded and you will make no power :(

so do you think I should sell the head and try and find the 99-00 head? What about using the cams out of the 94 head I have?

94-98 heads had HLAs 99+ inc vvt had solid lifters. I dont think that the cams are interchangable.

Jerry & I were discussing the possibility of running VVT off the boost control ouptut. Not as advanced as the Hydra, but should be functional. Untested theory.

Yeah, don't just unplug it

http://forum.miata.net/vb/attachment...chmentid=61181

Ohh...can I have my cake and eat it too?

there is no cake!

so yeah, square wave with 100% duty is basically a straight voltage and square wave with 0% duty cycle is no voltage. Switch at 4500 or wherever floats your boat.

the cake is a lie.

I dont see why it wouldn't work.

yea but in theory communism works too, and we've seen how that turns out.

Really? So you just switch it full off to full on? Seems really simple then, no need for any closed loop stuff.

It's just a solenoid...boost control tables work very well based on tps and rpm, could make it well very well. keep them open down low, and cruise for torque, closed for +4.5K and wot.


and really, the theory of communism is silly.

Seems to be working for Obama

Well, somebody needs to get on this shit and I'm certainly not the one to do it. Can you run 2 boost tables simultaneously on different outputs? ONE actually for the EBC, and THE OTHER for the bastardized VVT?

no, but you can run a standalone boost controller. there was a greddy in the classifieds but someone beat me to it.

i mean hell, if you just need to activate the solenoid at a certain rpm, the water injection circuit could trigger at rpm...

yeah but you're thinking on/off? I'd rather not only be able to run the 2 extremes. The stock ecu doesn't, and I'd suspect that no one with a Hydra runs the extremes either.