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Total timing on 110 Race Gas

2quick

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I will be taking the Satellite out to the track tomorrow for the first time. Up to this point I've only run 92 pump gas through the motor and the most timing I can run without detonation is 31 degrees all in by 2000. I will be running 110 race gas tomorrow and was looking for suggestions as to what I should/could be advancing the timing to.

Also I use a MSD Programmable 6AL so curve is made on a laptop....

11.5:1 (446)
440-1 Heads (Ported)
Indy Single Plane (Max Wedge Ports)
FAST Fuel Injection
.262/.262 @ .050 .645 Lift Solid Roller
4500 Lupo Dynamic Converter
430 gears
30" tall tire
2.77 low gear kit

IMG_5625.JPG IMG_4686.JPG
 
Wow. First time out, i would run it just as it is, in street trim. There's lots of experimentation just getting a new combo down the track.
That said, timing imho is determined by chamber shape, volume, and piston shape. Old mopar big block heads seemed to run best with 36-38°, more dome: more timing. I had a 302 chevy with 12 1/2 -1 pistons in it that simply would not run with less than 45°, it had domes that looked like the matterhorn.
I'm going to assume you have flattops and a fairly small heart-shaped chamber. I would bet that it probably wont need more than 34°. Maybe a little more with a small dome.
As i said i would try to get a baseline how it runs (mph) and then tune for mph increase. Start safe, add maybe two degrees, see if it goes faster or slower. Ad a little at a time till it slows down, then back up to the previous setting.
 
60cc chamber Flat top with valve reliefs.

Currently 31° on shell 92 is the absolute edge of detonation. 30° is probably safer. That said the car is currently almost out of fuel and I was thinking it's probably better to go to track and get a couple cans of 110 and add it in. At that point maybe bump the timing a few degrees to maybe 34°...The car has about 1200 street miles under it's belt and it's pretty dialed in but on on occasions (Not all the time) I can hear a slight hint of detonation. Could be brand fuel sensitive when running on the edge like that..
 
Once I switched to race fuel I found my engine ran best at 22 initial (for starting), and 38 all in by 2200. I also had to adjust the carbs a lot but I see you have efi.
Of course all engines are different, just my experience.
 
urrently 31° on shell 92 is the absolute edge of detonation. 30° is probably safer. That said the car is currently almost out of fuel and I was thinking it's probably better to go to track and get a couple cans of 110 and add it in. At that point maybe bump the timing a few degrees to maybe 34°

Sounds to me like you are on the right track, and should fairly close without a risk of any damage. HTH, Lefty71
 
I'm going to assume you have O2 sensors for your efi. They wont like 110 leaded much. Should be fine for limited use, but i would look into unleaded race gas.
I'm going to experiment with avgas, but i've just got a calibrated fuel leak.
 
34 degrees all in would be fine with 110 octane race gas. Your O2 sensors will be fine for quite awhile running race gas. Your engine might even like 36 total timing but start at 34.
 
[QUOTE="2quick

Also I use a MSD Programmable 6AL so curve is made on a laptop....

11.5:1 (446)
440-1 Heads (Ported)
Indy Single Plane (Max Wedge Ports)
FAST Fuel Injection
.262/.262 @ .050 .645 Lift Solid Roller
4500 Lupo Dynamic Converter
430 gears
30" tall tire
2.77 low gear kit

How does your car like the -1 heads on the street , good luck waiting to hear the results
 
You know what it like at max pump junk,with 110 I would make a baseline pass and either do a plug read or download the O/2 data.Increase the timing 2* and look at the MPH. Even if you spin off the line the MPH will tell the story.
Is the timing curved or is it flat? I have the same 6al-2 programmable and it also has a boost retard.
Take note of your RPM over the stripe! Plug readings are very usefull to see heat range,timing and fuel ring.
 
Here is the graph I've prepared for 110.

Distributor locked out at 38. Pulling 4 that gives me 34 Total with 22 Idle.

Racegascurve.jpg
 
Also I use a MSD Programmable 6AL so curve is made on a laptop
Could you elaborate a bit? If you want to, PM me, but I have been thinking that a programmable advance curve, maybe with a few "preset" for different circumstances like air temp, density, humidity, etc. would be the best way to go. What components are required to accomplish this and how does the rev limiter limit RPMs, and what is the increment that it allows for setting for example 10s 100s etc. Thanks.
I too have been wanting to be able to get a few more ponies when I run race gas vs 93 no ethanol, and I figured timing would be the only thing I could do. I run a FBO ignition system that is set to about 22 initial and 36 limited all in IIRC.
I have an Innovate Motorsports dual wideband O2 system installed, so I may be able to see the results of a more efficient burn by adjusting timing.
 
Indy -1s only need about 34 unless your running a large dome. I've run mine as far back as 28. It slowed it about .10
Doug
 
Just a follow up on what happend at the track the other night. Got the car out the trailer and pulled the drain plug to drain the tank. Went over to the speed shop on site and walked out wit 2 cans of VP MS103. Poured it in the tank and started it up. I hooked up the laptop to setup Data Logging and noticed the cursor for the VE table was off the chart. Thought to myself why would race gas, especially 103 unleaded, have made any noticeable change on the tune let alone make it untunable....in other words setting the curser so high in the table i couldn't even see it. When I looked at the AFR it looked OK at idle (around 13.8) but I did notice the 02 correction was pined to get it there. My FAST setup will only pull up to 15% fuel no more when needed. I revved it few time and seen the same thing across the board so I decided to make a pass and thought worse case it would be super rich but hopefully safe. Make one pass poppin, banging, and shooting 8" flames out the tail pipes. So I put it back on the trailer and went home. I think what happend is and I haven't confirmed it yet, But I think the MAP sensor took a **** at exactly the same time I put the race gas in....

For amusement here was my time slip....obviously left lane. I had to let out at the 1000' mark as seen by my 1/8 mph (95.7) being faster then my 1/4 mph (91.7)

IMG_0105[1].PNG
 
Here is the video. If you turn up the volume you can here the machine gun noises and see the flames out the tail pipes.

 
Dump the race gas (save it ,obviously), put pump back in, and see if your numbers fall back in line. If not, further sleuthing required.
 
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