Yellow Bullet Forums banner

1 - 20 of 36 Posts

·
Registered
Joined
·
38 Posts
Discussion Starter #1
I have a 383 with AFR eliminator heads and i had a 750 holley converted to E-85. The motor was running great with Premuim but now it is missing at lower rpm(1200-3000). I am running an autolite plug that is rated at a D11 heat range and I don't know if it is to cold or not I was running the Champion RC9YC plug and it was alittle colder then the autolite. The timing is locked to 38 degrees of timing. Anyone know what the problem might be, Mark sullens did the carb for me and he doesn't know what the problem might be he said that is sounded like it was cold but the engine temp was about 180Degrees. Thanks Josh
 

·
Registered
Joined
·
31,052 Posts
I have a 383 with AFR eliminator heads and i had a 750 holley converted to E-85. The motor was running great with Premuim but now it is missing at lower rpm(1200-3000). I am running an autolite plug that is rated at a D11 heat range and I don't know if it is to cold or not I was running the Champion RC9YC plug and it was alittle colder then the autolite. The timing is locked to 38 degrees of timing. Anyone know what the problem might be, Mark sullens did the carb for me and he doesn't know what the problem might be he said that is sounded like it was cold but the engine temp was about 180Degrees. Thanks Josh
That doesn't sound like an answer you would get from Mark. Ask him about it again, he may have misunderstood the way you phrased the inquiry to him.
 

·
Registered
Joined
·
38 Posts
Discussion Starter #6
I am going to try some smaller jets in the primary to see it this helps any. The i might try the plug gap thanks.
 

·
Registered
Joined
·
578 Posts
I don't run over .25 with ethanol, Mark is a great guy just call him back. If he did your carb for Ethanol I will guarantee that it's not the carb. A bad plug wire will act up down low more so than in the upper rpm.
 

·
Registered
Joined
·
578 Posts
What ignition system are you running? If you are running a MSD 6 or a 7 with the round coil you don't have enough ignition system to fire the fuel.
 

·
Registered
Joined
·
578 Posts
The msd 6 is not enough ignition system. You maybe making it work but you are missing out on alot of hp. I did a test on the dyno with my 632 on ethanol we started with a dig.7 and the good coil for it and made 1193hp we then put a msd 10 on the motor and made 1251hp (58hp more than the dig 7) the next thing that we did was we put a msd 12amp mag in it and made 1311hp (118hp over dig 7). When we first dynoed the motor with the dig. 7 the motor ran fine and made great power, we did not think that we had any issues. We tryed the new igniton system just to see what it would do, So in a nutshell we stumbled onto something with the ignition systems with ethanol. I'm just trying to pass on some info that I learned on the dyno, if this helps anyone then great. I didn't think that I had any issues with the dig. 7 either but it proved me wrong.
 

·
Registered
Joined
·
371 Posts
The msd 6 is not enough ignition system. You maybe making it work but you are missing out on alot of hp. I did a test on the dyno with my 632 on ethanol we started with a dig.7 and the good coil for it and made 1193hp we then put a msd 10 on the motor and made 1251hp (58hp more than the dig 7) the next thing that we did was we put a msd 12amp mag in it and made 1311hp (118hp over dig 7). When we first dynoed the motor with the dig. 7 the motor ran fine and made great power, we did not think that we had any issues. We tryed the new igniton system just to see what it would do, So in a nutshell we stumbled onto something with the ignition systems with ethanol. I'm just trying to pass on some info that I learned on the dyno, if this helps anyone then great. I didn't think that I had any issues with the dig. 7 either but it proved me wrong.
Is this a blown engine, nitrous, or n/a?
 

·
LSx Vega
Joined
·
1,622 Posts
My Vega running E98 initially stumbled out of the hole and like a bat out of hell would then take off. The lack of tuning knowledge on my part had me over fueling down low. I started leaning it out and it started going away until I was right where I wanted to be.
 

·
Registered
Joined
·
1,908 Posts
I have a 383 with AFR eliminator heads and i had a 750 holley converted to E-85. The motor was running great with Premuim but now it is missing at lower rpm(1200-3000). I am running an autolite plug that is rated at a D11 heat range and I don't know if it is to cold or not I was running the Champion RC9YC plug and it was alittle colder then the autolite. The timing is locked to 38 degrees of timing. Anyone know what the problem might be, Mark sullens did the carb for me and he doesn't know what the problem might be he said that is sounded like it was cold but the engine temp was about 180Degrees. Thanks Josh
What does your wideband say?
 

·
Registered
Joined
·
38 Posts
Discussion Starter #18
I am running a msd digital 6 box with a 50,000 volt coil for and hei destributer with 8mm wire. The distributer is for a computer controled car but no computer so i believe that it is locked, with and after market ignition modual. I am going to try the spark plug gap change and mark sullens also told me to try and take some out of the floats so it doesn't load the fuel as much. Been to busy to mess with it, i want to get it to the track though.
 

·
Registered
Joined
·
6,610 Posts
A couple things to try, you need to find out what it needs to fix it in the RPM range you have the issue. Try a hotter plug, try more or less timing, try a .005 smaller and larger idle air bleed. When you do limit it to the range you have the issue in to isolate what it wants in that range. Even the best carb won't work right if the engine it's on has other issues, in some cases the combination of parts in the engine require some different than normal tuning in the carb. Be patient, and you will work it out.
 

·
Registered
Joined
·
1,372 Posts
When it comes to E85.....
The one thing that I tell EVERYONE is to run a HOT plug (OR a normal gas plug) and keep the timing exactly where it would be on gas.....


ok i am using autolite 3924 heat range d11
not sure what that D11 means, autolite heat range is based off the last number in the part number....and yours is a 4

From the Autolite home page:
for domestic manufacturers like Autolite (and Champion), the higher the number, the hotter the plug.
Your 3924 is a COLD plug, and while this plug may work ok with METHANOL....(or Nitrous.)

...its not working with E85.

From the Autolight home page:
the difference from one full heat range to the next is the ability to remove 70°C to 100°C from the combustion chamber.
your combustion chamber is running about 200* C too cold....
200 ºC = 392 ºF too cold......its no wonder its blubbery.

Take the Jetting back to where it was when I shipped it, to give it the fuel that it wants......

and put the correct heat range plugs in it......
try a Autolight 3 9 2 6

Its not in the carb....its in the ability to fire the fuel.
 
1 - 20 of 36 Posts
Top