Carbureted LSX forum - carb/ cam only ls2 guys...
07-05-2012, 12:40 AM
being i couldnt get any tuning in at the track before my 6012 took a dump, where are you guys timing wise? just looking to get a general baseline. i started at 26* and went up to 30* after reading some of the setups listed in the timing thread but they seem to be all over the place. some guys are in the mid to high 20's and some guys are in the mid to high 30's with around 11 to 1 compression.
its all in just off idle
should i go back to 26 or stay where i am?
07-05-2012, 09:01 AM
There is a good post in here if you do some searching. They looked at timing vs intake design rather than timing vs compression ratio. Seemed like the guys running a single plane could get away with more timing than guys running a dual plane. Im at 27 deg on mine, but I haven't spent much time trying to optimize it.
07-05-2012, 11:48 AM
lots of views and no solid answers. guess i'll just have to wait till fall and try it out again.
it ran good numbers at 30* but i guess we'll see...
Pop N Wood
07-05-2012, 12:03 PM
Look at some of Speedtigger's, 3pedals and zones's posts. All of those guys posted track details on why they settled on their max timing. Most were in the mid to upper 30's IIRC.
Every set up is different but most guys are seeing gains with higher advances.
I agree that timing curves seem to be all over the place. Sort of why I still haven't fully settled on one. I do run 35° max static and 10° max vac advance.
07-05-2012, 12:26 PM
in my 13.5:1 ls2 with ls3 heads my timing was at 44 peak with 110 octane.i took my car to a dyno and i kept adding timing 1 degree at a time until i lost torque and power.then i set it back to where the max was
07-05-2012, 02:42 PM
Go to the track, start at 30*, bump it up till you lose time, step bak to the fastest MPH.
07-05-2012, 05:20 PM
I am thinking track tuning is the only way you are goint to know for sure. I have track tested mine and it does not like as much timings many others.
I would say the head style, compression ratio, manifold type, cam size, cam advance, fuel, elevation, etc etc will all play a role.
Just have to work it out and share what you learn.
07-05-2012, 11:20 PM
yeah i planned on doing the fine tuning at the track, but i wanted to see if there was a general consensus on a starting point. there is no way i am winding 35+ degrees into a carb'd 11 to 1 motor on 93 octane without having hard data of my own to justify it lol.
Pop N Wood
07-06-2012, 06:29 AM
My LS2 has stock compression, can't remember if it is 10.5 or 10.9:1 and it runs with 35° max advance on 93 octane gas.
07-06-2012, 03:56 PM
its actually 10.9...but thats close enough to 11 to 1 for me lol
07-06-2012, 04:18 PM
My Lq9 with 11:1 on 91 octane Holley 850 carb is 33*
starts at 9*
800-1200rpm Idle is 19*
all in @ 33* by 3400rpm