Don't want to think about it right now. Anyone have a VVT head?
Yes, actualy. I boxed it up last month as it was ready to ship to Bogus for some hard lovin' but then I decided to get married and now I'm broke as ****. As much as I WANT Vee Vee Tees, its going to be a looooong while until I get the scratch together to make it happen.
PM me if fro serio, I'll give you all the info I have on it and won't ask for a nickle more than I paid.
Not to hi-jack your thread, but what would cause a head to drop a valve? I assume it broke either where the stem is cut for retainers, or where it flares out for the head. Wondering what we can do to prevent this?
Dem, Thanks for the great build thread that has given us lots of great ideas and insight. No one here doubts you will be up and running like the **** you are very soon! And of course we expect pics.....Didn't you say you would have the GoPro going?
Head was stock. This failure was probably caused by floating a valve. I did a couple of pulls and had some misfiring but assumed it was from being too rich or spark blowout. The valve springs couldn't return the valve quickly enough and they basically bounce or stay open and can make contact with the piston.
How fast were you spinning her? What kind of boost? Have you had any decisions about what springs you will use? I chose the ST dual lite setup in hopes to never find out how you feel right now.
The best thing about part failures is that they can pave the way for bigger and better things. I imagine a built head with a nice porting would help immensely, making your power goals achievable with less boost.
Oh, and if you were on the Speed Industry dyno, that thing is notorious for reading low...even lower than other Mustang dynos. 400 on that guy is probably roughly equivalent to 450 most anywhere else.
What was failflora's? 350whp @ 30+psi? You sir are doing something right. I have the utmost faith in your skills to not only rebuild it correctly, but to blow those current #'s out of the water with a nice pnp vvt head.
On another note...does this mean I have the fastest, running Michigan miata now?
Started my day out with a nice coffee... Laptop was charged.. delicious steering wheel was awaiting the ride to the dyno..
I had my map setup as a hybrid boost comp table and things were going great - I unplugged the waste gate line and basically tuned it perfectly at 14 psi across the board. Then basically copied the cells all the way up and let boost comp take care of the rest. As I started to ramp up in boost things were going beautifully. Boost comp was doing it's thing and making my job easy.
As I got close to 20 psi the car started to make some really impressive numbers. 380 something at 20 psi. My torque curve was seriously impressive. Not a single bottle neck in the system holding me back. The BEGi manifold 100% solved my torque curve issues. It was basically making more power with RPM and didn't show signs of choking out at all.
Now getting near the 24 psi mark I started to notice a misfire at around 6500 so I checked my timing and added a little fuel. Ran it up a couple more times with the same problem.. The timing was looking pretty retarded for E85 so I gave it a degree or two more and it went away. Then I moved it up a notch and got one pull out of her before the failure in cyl 4. The pull itself was actually not awful, but just at redline I let off and you can hear a ticking noise all the way back down. The car shut down pretty quickly and would not fire back up.
Pushed the bitch off the dyno and headed to the bar.
Now I'm debating building a nice VVT head or going with a cammed out non-VVT built head...