February 15, 2019, 07:23 AM
BrktracerTwo Step really loud....
quote:
Originally posted by fuzzy dice:
quote:
Originally posted by Eman:
What RPM are you leaving at?
3200 right now...that may be it, I guess...
I'm not convinced that's too low. I've been as low as 2,700 without the issue you describe. Leaving off the bottom may not allow much higher rpm due to reaction time. I completely agree with the above comment about making sure the wiring is in good condition and strongly advise running 10 ga wires from the box directly to the battery (or master switch). I have to wonder if the air/fuel ratio is having some impact as well. Maybe it is rich or lean at this rpm and hard to tell because the engine is never otherwise at this rpm under WOT except on the limiter. I'd suspect maybe rich? What are your carb details?
I'm leaving at 3,100 and changed from a 7al-2 to Grid last year and really can't tell a difference in how the engine sounds on the "2-step"
Thanks to topfuel for the link to Reher's article. Great information!
February 15, 2019, 08:30 AM
Lenny5160quote:
Originally posted by Brktracer:
quote:
Originally posted by fuzzy dice:
quote:
Originally posted by Eman:
What RPM are you leaving at?
3200 right now...that may be it, I guess...
I'm not convinced that's too low. I've been as low as 2,700 without the issue you describe.
I agree with Matt. Off the bottom bulb I live between 2700-3100. Usually 2800 or 2900. It feels a lot more lazy leaving that low, but it doesn't sound any better or worse than 3400 or 3800 off the top bulb.
I've occasionally had one or two pops which I assume is raw fuel in the headers, but that is very rare.
February 15, 2019, 08:58 AM
EmanI was leaving at 2800 last year with a 6AL and it never sounded loud or odd. Tons of 6AL boxes around have you tried another?
February 15, 2019, 10:38 AM
FootbrakeJimAs others mentioned, it could be an overly rich fuel mixture, causing some raw fuel to burn in the exhaust. Also, later ignition timing definitely makes the exhaust tone louder.
Speaking of which, when you say "louder", is that referring to the noise volume, (decibels), or the amount of popping and banging? If you have large turbo-style mufflers, it seems to me like they can almost amplify the popping sound of a 2-step, just because you aren't hearing nearly as much of the surrounding noise that you get with open headers.
February 15, 2019, 10:57 AM
BP758Our big block stocker bangs hard on the step. It’s the digital 7. I’m not buying into the hype of step damage. We just don’t see it. We don’t do long chip burnouts... On the TS ride We have a burnout chip, launch chip and never hits the higher chip. Bearings, pistons, rings and valvetrain are perfect after 200 plus runs every year running 6.70’s over 204 @ 8400- You could run the bearings again. We replace because of guilt... Leak at 200 runs is still 2%. Maybe we’re doing it wrong but I’m not changing anything! Pretty solid Engine platform.
Btw, lower is louder on the stock motor like 2400 (big wheelies) and 3400 tuned up is definitely quieter.
February 16, 2019, 10:03 AM
The HawkI had a similar situation with my Skyhawk. I was too rich with pump gas. On the 2 step it sounded like a shot gun going off and horribly distracting and was shooting out 3` flames out the headers! Went back to race gas and it went back to a normal smooth limiter.
February 17, 2019, 05:46 AM
fuzzy diceWhen I say loud, I am speaking of the decibel level of the pops and bangs...I am slightly rich but we dyno tuned her recently so the a/f is pretty good...
February 17, 2019, 09:16 AM
The HawkYep, that's what I had going on. At the time I was running regular unleaded. Higher octane got rid of the issue.
February 18, 2019, 12:01 PM
fuzzy dicequote:
Originally posted by The Hawk:
Yep, that's what I had going on. At the time I was running regular unleaded. Higher octane got rid of the issue.
OK thanks...I run 93 octane in mine...