Ok guys, I know nothing about nitro, but NEED to! http://www.jalopyjournal.com/forum/showthread.php?t=728009 In our quest for 200 mph with the flathead, we'll be running on fuel. Any pointers on the use of nitro with a blower is appreciated!
Now, we're talkin! I can't give advice other than take a lot of spare parts and hold on! Well, what about your ignition? Magnetos are very good, like an MSD but i'd be looking for a MSD 10+ box, coil etc They are hard to find, MSD quit making them, but they are wicked powerful and tuneable. I think Willie Glass used one. I've used them on tubo & nitrous drag cars and they will light off a heavy dose with lots of turbulance and no unobtanium spark plugs - off the shelf autolite racing or ngk. But, they be hard to find. They get snapped right up if somebody cuts one loose, i hear they are going for over $1K.
Steep costly learning curve is what I've been told. Learn an alcohol setup first and then sneek up to 25%. After 25% everything changes and you really need someone with years of experiance to help to keep the damage down. I'd be running alcohol first and maybe that's enough to solve the power problem.
we used to run alcohol and 5% pop in my brother's racing cart. Needed to keep a spare cranks around on race day. No other experience with real motors and nitro.
Ahhh,,,,,POP,,, now that is an old term,,,a cool old term. They say when you get to where you can light 100 dollar bills and not flinch,,then you are ready for fuel ! Tommy
We'll be running a crank trigger, HEI, boost referanced MSD box, etc. We'll be trying to stay on lower levels of pop-just enough to raise us from 570HP to 800HP.
Buddy, you know that I'm also learning, but I have gotten the same advice as Gas pumper said here. Tune it on Alky, then try with a 25-30% blend. Less meens you have to lean, more enritchen. It's also said that with 25% you don't have to do anything with the setup if it runs correct with alky. With the flow mods. etc. that you will do and with straight Alcohol a litle more boost, I wouldn't be supprised if you see 700+HP!! Kjell ............................ Taildragger&fenderless
Rule #3 Adding fuel (which is carrying an extra oxygen molecule) can contribute to a lean condition, all other things being equal. Hmmmm, Confucious say WTF........over. For questions, reference Rule #1 above!
i like what yall are doing and wish you luck i know nothin about that stuff, just gas with a little racing fuel
I scaned through your origional thread but didn't see if you were using carbs or if it was injected. I'll assume you're using gas now and with some math you can get pretty close. The only reason I would use a lower percentage (less than 80%) even to start with, would be if your fuel system couldn't flow enough. Then you could taylor your percentage to what you can flow. It's not the percentage that will get you introuble, it's the volume. It's far easier to set the fuel system on kill and leave it alone, then use timing to calm it down or step it up. Before I too much farther, tell us what your existing combo and tune up is on gas and we can go from there. There seem to be a lot of myths and misconseptions about nitro going around, but with some solid science and math it's not as mythical as it appears to be.
I think you will be surprised at how much more power just going from gas to alky will make. You can spin the blower a little harder and add some port nozzles if you still need more power. Have you given much thought as to what are you going to do with the intercooler? It won't be needed anymore either. Nitro is fun, but its hard on parts, and flathead Caddy parts aren't easy to come by.
We currently run a racing mag, locked at 26 deg, an Enderle bug catcher with 26 nozzles, Hilborn 1/2 size pump, and a 105 return jet at 14.7 psi boost. That combo produces 570 HP, and 544 ft/lbs torque at 5500 RPM. We'll have 2 tunes- the current obe for the gas classes, and the HEI setup for fuel. WE'll continue to run the chiller- may not help with fuel, but it won't hurt us! We can go straight alcohol, and spin it harder- in fact, we'll tune it like that on the dyno. I doubt, though, that alcohol alone will move us from 570 HP, to 800 HP. So, a little POP in the tank will be necessary!
This is the guy I go to for fuel injections advice. Look for his section Nitro Notes. http://fuelinjectionent.com/ As others have said get more money. You will break stuff and the nitro itself is expensive. I tune a blown alky boat and the owner (brother) wants to see how fast he can go with an iron block BBC on nitro. Much carnage is expected.
Need to find the happy medium , Worked on a lot of cars that didn't try to kill themselves every pass, it's all about getting a good tuner , Me, I was a diver , mostly fixing what a bad tuner can do Tim Jones
I would contact Flathead Jack. He runs his dual engined flathead dragster on 94%. I have no idea what differences would be necessary with a supercharger, but wouldn't think too much. Too bad John Bradley is no longer with us. He was the flathead nitro master Jim
Just curious, does adding, lets say 25% nitro move you into a faster class at Bonneville? Do the rules differentiate between a car running 25% and a car running 75%?
Rule of thumb is double the volume from gasoline to alcohol, and then double it again for nitro. The optimum amount of lead you can run is more or less dictated by bore size (ie. 4 inch bore will take 40 degrees the same way a 4.25 will take 60). Exhaust valve opening point is the key to making power. The longer you hold it closed, the more power you're gonna make...too long and you run into bottom hole detonation. The whole thing is super load sensitive. Engine will pick up and drop cylinders based on the amount of resistance the crankshaft sees, and the engine does not care if the difference is through weight, traction or aero. Your initial tune-up should have zero fuel returning to the tank...only return it to the tank after you've tried to burn it with load first. Higher percentages are easier to tune and keep clean than lower percentages. You're less likely to break shit at 80% than 30. Plugs only tell part of the story, learn to read the top of the pistons and cylinder walls. When you click the motor at the end of a run, everything uner the heads should be wet and oily. Treat the Bitch-Goddess Nitro with care and respect, and she'll be gentle as she rips off your face. Have fun with the sickness....
Nozzle pressure with gas was 90 psi. I'm sending both pump in to get flowed, as I have no numbers now. Thanks Tim- I'll try and call you today or tomorrow. Thanks for the info!
WhitePunk knows what he is talking about,,I remember him from a long time ago. A racer,,,magazine guy,,from far away. Now he sells fuel,,,,,so to speak,,,LOL. Tommy
You could optain the HP desired w/ nitrous........it would be cheaper all the way around, unless the rules do not allow it....It has been around longer than most would like to admit.....Ran it on my six-two 94 carb setup...had 12 jets in the carbs to get right and another 12 jets to get right in the nitrous system in order for them to work in concert and make the most power w/o going pop another way.........Doing it this way can be as catastrophic as running nitro by making the wrong move as well.........Littleman
Before you put the engine on nitro and make a pass, buy a good pair of fire proof underwear............. ): That shit will burn you up if your not veeeeerrrrryyyy careful. Speaking from experience.
There's a thought! No carbs though- how hard do you think it would be to set up with a Enderle bugcatcher? It is legal in the fuel classes.
It wouldn't be hard to do. In fact someone even used to make a nitrous plate that was sized for a bugcatcher opening.
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