nitro mixed with M1 fuel

[nyesgym]

been a while since I posted. my 71 Vega SBC N/A now runs 4.94 at 141 mph with a 1.09 sixty ft. I am running VP-ATM fuel, which most people have never heard of, but it works. But VP is going to stop making it. SO, I want to take M5 fuel and mix 50/50 nitro mix from VP with it to add more power. Has anyone done this ? or just add 50/50 nitro mix to M1 fuel ? what are you doing with your timing when adding nitro ? and say you make you mix 8% nitro, how much timing will you add ?

[ProPower engines]

The M-5 does not have any nitro in it but it does have an oxidizer and I do not know if it would be easier to just use M-1
rather then the M-5 to blend with as I don't think it would be a good blend. Talk to the VP guys they should be able to make a suggestion

[69427]

Mixing 5 gallons of VP NITRO RACE 50/50 in a 54 gallon drum of M1 will give you a ~5% mix. This is using a hydrometer with temp calculation. I also use 1 bottle of M2 top lube in the mix.

Obviously you would have to remove 5 gallons of the M1 from the drum to add the 50/50. I find this is cheaper than buying M5. My timing is already 40-41 normally, I do gain a little mph with 1-2 more, but usually don't bother.

[nyesgym]

currently I run 28 degrees of timing, 1 degree more or less I lose power. But now adding % of nitro to the mix, how much more timing ? and if my msd 8 plus box and power grid will not fire the mix, is it because I need a Mag to produce more spark ? or just lean it out until it runs good ? what air/ fuel ratio am I looking for in a 10% mix ? and ETG ?
does any body know

[69427]

FYI I run the 7720/7730 power grid combo and the 8261 coil and have no problems lighting it off even with a 4.9 AFR on the Racepak O2 sensors. That 8 box should work great.

I can't give you a straight answer on the timing, but adding timing lowers my EGT's. FWIW.

It's a balancing act!

[Dave Koehler]

Clarify please.
You are planning to run 50% nitro?
With a carb or mechanical injection?

[nyesgym]

Kinzer down nozzles ,mechanical injection , going to run 10% nitro with M1 fuel plus top lube

[Dave Koehler]

If you already have a good tune on alky, up to 20% leave your main jet and timing alone.
You can tinker with it of course.
30% I usually tinker with the timing a little.

Above 30%...stop, turn around, rethink your goals.
Between 30 and 80% is very shaky and potentially expensive territory for most. Nitro is just weird that way.
IF you have one of those combos that has diesel compression like 14-17 to 1 it would be wise to stay with the 10%.

A hydrometer and thermometer will be your friend.

If you contract the yellow fever skip right on up to 80% and above but be aware that you are no longer in let's have some fun land.
Bigger fuel pump, Compression, cam, gear ratio, ignition and wallet all come into play now.

[nyesgym]

I have 42 cc heads 15 degree brodix 17-1 compression and not going over 20% for sure

[nyesgym]

with say 12% nitro, what air fuel ratio am I looking for ? what ETG ? last run out, with 10% nitro, my air/fuel was 5.15 and my ETG was 1224, motor sounded good and I ran my best pass at 4.88 atb140.77 mph in 1/8 mile ,[drag car]

[Dave Koehler]

I work from spark plugs and ET.
I can't speak to ETGS but EGTs are useless as a magic tuning number.
So, IF you got your quickest pass, the plugs are in one piece and you want to tune by A/F then it follows that 5.15 is a good place to be.

[nyesgym]

Charlie Dolbin says Hi, says you made some intakes for him years ago. And that you know your stuff. and thanks for advice. I believe , 12% will get me where I want

[Dave Koehler]

Charlie is too kind but I will take it on the second Monday.

[John Wallace]

12% will get me where I want

And how much HP is that do you think?

[nyesgym]

well 5% nitro gave me 35hp on the chassis dyno, that I know, aug 22 I take my car back and will be trying 12%