y8s

iTrader: (8)

I can post copies of the 01 pages if i get time

MikeRiv87

iTrader: (12)

Never mind, I just went out and looked at my 01 Miata for a referance of what is going on with the vvt solenoid. Basically i need at least the one pipe that connects to the solenoid and runs front to back on the valve cover. Waiting on a reply from seller whether it comes with the valve cover or not.


That would be Great...

sn95

iTrader: (2)

If you have a degree wheel (or can borrow one) you should be able to determine basic specs on the cam. You can only measure lift with the dial indicator and no degree wheel..you can measure lift and duration (particularly duration at .050 lift which is much more meaningful than "gross" or advertised duration). If you are checking the cam "out of the engine" it is going to be a bit more difficult because you don't have a measured Top Dead Center (TDC) position to use as a reference point. Also remember that if the degree wheel is attached to the cam, the indicated degrees will be cam degrees (not crank degrees which is how most cam specs are quoted). Advertised duration is the number of degrees from when the cam lobe shows nominal lift (different companies use different reference points, typically .001-.006 lift depending on cam manufacturer).

So, start the cam in a set of V blocks with a degree wheel firmly attached to the cam, a pointer secured clamped in front of the degree wheel and the dial indicator zeroed on the base of the intake cam lobe. Slowly rotate the cam until the dial indicator shows .006 lift. Make a note of what the degree measurement is front of the pointer (A). Continue to rotate the cam in the same direction until the dial indicator shows .050 lift and record the degree measurement indicated by the pointer (B). Continue to rotate the cam until the dial indicator shows the peak lift on the nose of the cam lobe. Record this as the intake lift measurement. Continue rotating the cam down the lobe until the dial indicator once again shows .050 lift (C) and record the degree measurement. Continue rotating the cam until .006 lift is shown on the dial indicator and record the degree measurement (D). Compute the cam specs as follows:

Advertised duration = (D-A) x 2 (multiply by 2 to convert cam to crank degrees)

Duration @ .050 = (C-B) x 2

Lift = Maximum lift number indicated when the dial indicator is on the nose of the lobe.


Repeat the same steps for an exhaust lobe and you will be have the basic specs for the cam.

Mitch


[QUOTE
Paul, there's not a lot of data on the 01 intake cam. If you tell me how to measure it, I will. I have a spare 01 head, a dial indicator, and a protractor.[/QUOTE]

sn95

iTrader: (2)

Quote:
in any case, turbo cars like modest duration and high lift. there might be off-boost or low rpm gains from using the 99 profile but it hardly seems worth the effort or cost to do that over a custom cam grind.


Not really. Turbo cars choke with too much overlap. Very long duration cams generally have a lot of overlap (e.g., intake and exhaust valve open at the same time, great for cylinder scavenging on a high RPM NA race motor, not so great on a turbo car with 15 psi of boost). A turbo car will always make power with longer duration cams as long as overlap is kept to a minimum. Just like in an NA application, longer duration cams in a turbo motor move peak torque and peak hp to higher RPM points and generally reduces low end power, throttle response and street manners.

High lift, modest duration cams are good street choices for both NA and turbo cars if and only if the lift profile of the cam does NOT exceed the "stall point" of the cylinder head ( a .550 lift cam is useless on a port where flow stalls at .500) or the limits of the valve springs, keepers and retainers.

sn95

iTrader: (2)

If someone can supply the VVT cam specs and intake/exhaust flow numbers for a VVT head, I'll try modeling the VVT cam/1.8 motor in Sport Compact Dyno Sim.

compy

My VVT makes my engine makes a noise that I believe is knocking when the engine is cold. Started when switching the timing over to MS. Unplugging the VVT makes it go away, but the car doesn't run as well. Probably something you have to take into consideration....
https://www.miataturbo.net/forum/showthread.php?t=20699

compy

Quoting y8s from the other thread:
"worst case, you put them on a switch or figure out how to set them to < 1500 rpm AND < 60°C coolant temp."

WI doesn't work off coolant temp, only air, right?

y8s

iTrader: (8)

dingus, that's VTCS not VVT. ignore compy.

eunos1800

The Adaptronic Supports VVT, damn site cheaper than the Hydra as well.

http://www.adaptronic.com.au/products-e420c.php




Cheers
Mark

05pearl

iTrader: (4)

I decided to bump and old thread instead of starting a new one. Story is:

I purchased a built motor. It's a 94 block with an 03 VVT head. The motor is in the car right now. But, as you can see by this thread, there is no oil supply port for the VVT. We are trying to figure out if it is possible to use the 1/8 BPT oil pressure sender under the intake manifold and share that to feed the VVT.

Does anyone know if there is enough oil supply here to feed the VVT? Will it affect the OPS negatively or cause any issues that I am not aware of? Or, is there another, better, location to supply oil to the VVT?

Any advice would be appreciated.

timg

In for answer to above questions!

Savington

iTrader: (31)

The factory uses that BSP port (?) for the VVT oil feed. Their feed line has a built-in tee for the stock oil pressure gauge. The one thing I am unsure of is whether the thread changed in the block for the VVT motors - the 01+ motors use a banjo bolt but I have never bothered to check the thread to see whether it's metric or BSPT.

NiklasFalk

iTrader: (1)

The banjo bolt to the block is M10x1.0 (just checked on my loose line). I forgot to check if the Oil pressure contact (on that line) uses BSPT, NPT or M...

Savington

iTrader: (31)

Good to know. I would expect that inline oil pressure port to be BSPT.