[chevette]

Rons flying toilet - no high speed. They told me I didn't need one. We just put a new set of heads on the truck picked up every where. Never had this problem before, with the other heads. making more power now. I deal with it, but I was just thinking maybe its time for a high speed.

 

[Uncle Paul]

Rons flying toilet - no high speed. They told me I didn't need one. We just put a new set of heads on the truck picked up every where. Never had this problem before, with the other heads. making more power now. I deal with it, but I was just thinking maybe its time for a high speed.

Don't need one? Well yeah you can get by without one with methanol because you can run really fat and not foul a plug but I don't know many motors that have a linear fuel curve. If you want give Brad @ Kinsler a call and pick his brain, he is a master at fuel injection and can hook you up. A high speed by-pass does not cost that much and if it means more mph you might like it.
I am presently building a 556 BBC with my same system on it. I should be on the dyno in about 2 weeks so I will post my finding on fuel curves and such. Oh and I am going to run the new VP M5. Think I will crank it up and rip off the knob.

 

[Horndog]

X2 on the Kinsler unit. That's what I ran. Once it's set, you forget about it, just like the rest of the system after the sweet spot has been found.

 

[WJ Birmingham]

Before you even mess with a high speed, which if you're running a high compression motor, can help you lift some ring lands...

You'd be best to know EXACTLY what your fuel pressure is on every pass. I'd hope that when you asked about EGT position, you have a full data logger and not just a EGT logger.

Start your high speed at about 10 PSI less than your top fuel pressure, and start with a VERY SMALL jet. Something in the area of a 40-60. Watch your EGTs and start leaning it down (bigger jet and less spring pressure) until the egt's dont change much from launch through mid track.

Remember, the barrel valve adjustment is your idle mix and to some extent your accelerator pump shot. The main jet on the barrel valve is like the main jet in a carb. The BV adjustment should only be used to control idle temp as well as the response from the whack of the throttle.

After that, the nozzles and main jet (and high speed) control everything once you're at WFO.

If you want consistency out of the system, invest in a weather station and make adjustments every round to the main jet.

 

[Horndog]

WJ Birmingham, sorry but I don't agree with your last sentence about "making adjustments every round to the main jet".

Now I know what I ran (Enderle Hat on a tunnel ram) is a little different than the toilet, chevette is running but once the "sweet spot" has been found and the car repeats, and the EGT's are good, I see no reason to keep wrenching on it. Both systems are still mechanical constant-flow units.

In over eight years of bracket racing every weekend, the main pill and barrel valve setting was never changed on my car. What it ran that day is what it ran that day. The et's went from a 5.55 quickest in the fall, cool crisp air to 5.65-5.69s during 100 deg, 95% humidity summer days/nights. And it was consistent as hell regardless of the ambient condidtions. Just had to dial for the changing track.

 

[WJ Birmingham]

Well hell, I guess I wasted all that money on a full flowed jet /nozzle compliment and weather station.

I'll just throw em all up on Ebay dirt cheap.

Sure, if you run it pig fat, it will be consistent.

If you're serious enough about wanting to put a high speed lean out on it, then you should be serious enough to be making fuel adjustments round by round.

 

[Uncle Paul]

Two schools of thought, neither wrong:
Horndog your happy leaving it alone as long as it is consistant and you can go rounds, thats cool.
WJ you like to tinker and squeeze every bit of Hp out of it on any given day and that is also cool. (thats me I will admit)
Now play nice..
Thing is if you going to tinker you need to keep records, take data, and make small changes or it will bite you in the behind faster that you can blink.
Chevette, if you already running the toilet you have the basics down, adding a High Speed by-pass you will be able to tweek some more Hp and MPH out of you motor. You can add a HS thats is set to high pressure and slowly reduce it to find your "sweet spot"
WJ, I never lifted the ring lands but I did boil the cement and pepper the plug with aluminum a few times. Lean is mean but you can go too far.

 

[Uncle Paul]

I forgot, while we are on the subject if mechanical fuel injection. Another person that is great with systems is Spud @ http://www.fuelinjectionenterprises.com/ He is "The man" if you think you might want to add a splash of CH3NO2

 

[Horndog]

Well hell, I guess I wasted all that money on a full flowed jet /nozzle compliment and weather station.

I'll just throw em all up on Ebay dirt cheap.

Sure, if you run it pig fat, it will be consistent.

If you're serious enough about wanting to put a high speed lean out on it, then you should be serious enough to be making fuel adjustments round by round.

Hey, I wasn't slamming you or what you said. No where near. It seems you and I just approach our racing from different perspectives.

I too spent good money on flowed jets / nozzles. Tim Engler flowed my system on his bench and he doesn't work for nothing.

No, it was never even close to running pig fat. Ran the same set of plugs the last two seasons and never a drop in performance.

 

[Uncle Paul]

Don't you just luv the smell of METHANOL in the morning? :supz:

 

[Horndog]

Yep !

But NITRO keeps me awake !!!