124T timing curve

[gordonr]

I put a S&S 124T in my 04 RK last Nov and had gotten a bargain on a TMAX to go with the install. I have called S&S a few times recently inquiring about their recommended timing curves @ sea level. I initially set the timing on the "timing vs eng speed" page at 10* for idle and 28* all in by 3840 rpm.  (There are no tuners avail that know the system locally.)  S&S recommends seting base at 17* to 20* and 26* max by 3700 rpm. I have always set base timing low to keep temps down when I'm in traffic so I felt their recommend was a little high. Is the 26 * max advance recommend a "safe zone" for there warranty? I have always seen non hemi chambers running higher timing than that . The bike starts and runs fine, just looking to fine tune. I used map #827.

[Merc63]

I just did timing on the 126".  I saw around 0.5-1hp change going up and down 2*.

I went as high as 32-34*, down to around 26*.

I was using a map supplied with the DTT TCFI for a built 95" and it seemed to work really well.  Only spot that I needed to take out was 4* from 2200-2750 as it was bucking if I feed it too much throttle.

I settled in around 28-30* from about 5000-7000rpm.



26* seems a bit safe, but in reality, it's only going to cost you maybe 1-2hp, nothing you would ever notice.

[strokerjlk]

26 deg max sounds fine
But I would do the 17-22 at idle .

[gordonr]

Thanks Stroker, Merc63.

[strokerjlk]

Thanks Stroker, Merc63.

no prob

I have always seen non hemi chambers running higher timing than that .

when I first saw that video of the 120 you were involved in, what stood out to me was the 33 deg timing at idle
what would you set the idle timing at on a 13.1 hemi 117, with S&S 640 cams and the Forced induction 2-1 that were popular on the early hemi builds.
S&S D makes 140's for hp.

[gordonr]

We ran 33* in Bonneville around 4000ft. At 800ft in Chicago we ran 22* to 26*. Two different fuels. Most all the kits sold at Hemi were sent out at 26* to 27* max timing set in the modules. From 10.5 to 11.3 cr.

[strokerjlk]

We ran 33* in Bonneville around 4000ft. At 800ft in Chicago we ran 22* to 26*. Two different fuels. Most all the kits sold at Hemi were sent out at 26* to 27* max timing set in the modules. From 10.5 to 11.3 cr.

thanks

[gordonr]

I have gone no higher than 16* at base with hemi chambers. But your squish band will have a lot to do with your chamber design. Does your piston have a radius that fits up inside your segmented chamber? My documented 139hp 95" at Wyotech was set at 10* base 25* max. I ran my bike down main street in Daytona several times that year and it ran much cooler than my stock RK.

[strokerjlk]

Yes the piston and chamber are radius .
It's not my bike . A friend of a friend has it.
He doesn't ride it much anymore. But every time I see him , he has questions .
I had him set the idle timing at 18 deg . And total advance At 26 deg .
One of these days I think he will switch to a DTT ignition and tune it .
He runs 110 Sunoco in it now and doesn't do anything but short hell rides . 
He doesn't think it could ever be a street ridden bike on pump gas .
I think it could with a good ignition . But he has a newer bagger now , so the dyna may never be more than a hell rider .

[gordonr]

We have never run that high of an octane fuel with that much success. Even at the shootouts we run 93 to 106 octane.

[strokerjlk]

We have never run that high of an octane fuel with that much success. Even at the shootouts we run 93 to 106 octane.

Yeah it's just a mask . It's what we can get local .