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Hey guys just curious what y'all think of this timing table. I had a guy from a speed shop set me up earlier this year and car ran really strong but as always second opinions are always welcome. Engine is an iron block forged 370, 233/235 .621/.619 @.050 116 lsa 114 icl cam, LSA cylinder heads, BTR trinity intake, vs racing 80mm turbo, Bosch 210# injectors, Icon 102mm TB, Holley Dominator. Currently hitting 16 psi on 94 pump(no ethanol). The guy was saying it's about 16* idle, 36* cruise, 14* WOT
Timing is engine and combo dependent, start low and slowly feed it more watching the plugs for the timing mark and/or checking power gains/losses with a dyno or track mph.
But my 0.02 is at 16psi it's a little hot. I like to start at 12 degrees at 16 psi, I get this working from Matt's 14psi 14 degree pump gas baseline. The lower boost levels seems way hot to me, at 0psi you have 38 degrees. I've never seen or heard of an lsx engine wanting more than about 28 degrees na. Between 0psi and 14psi it's hot also, and the idle timing seems low to me 18-22 is what I've found. Yrmv
It's impossible to tune a car like this just by looking at the timing table and given a few bits of information about the combination.
There are some "general" ideas that can be shared, but that is about it. What is the compression ratio and at what rpm does it come into boost? We don't even know if the commanded timing in the tune is where the timing the motor is actually seeing. In other words you might think you have 16 degrees of advance, but you may only have 6. The spark plugs will tell you if it's too hot or what your afr on that individual cylinder is. You also need a dyno or mph at the track to see if more timing is even beneficial and what power it may have gained with those afr or timing changes. Many, many things to consider that we don't have here.
The guy was saying it's about 16* idle, 36* cruise, 14* WOT
looking at the screenshot, its way off from that. timing is pretty aggressive. 38* at na wot, cruise is probably in the 42* range. 16 psi is 14* but 14 psi is almost 20*
did the speed shop think you had a stock 454 with open chamber heads lol
I agree with everything above and surprised you haven't broken anything yet although it may not be as bad as it seems if actual timing has not been confirmed
agree if it hasnt kicked a rod yet the actual timing is either off , or your the luckyest dude ever. thats pretty hot timing even on e85 id worry about lifting a head .
From my experience, having higher (than stock) idle and cruise timing is the move for ls turbo combos. Maybe Andrew B who's a tuner who hangs out in here would share some thoughts.
I didn't look at the tune but from my experience running a lot of timing for small boost is not unusual... but by the time you get to 15.... 20+ my tuner will put an SBE into 13-15 timing but more timing for a forged combo. I've got a buddy running a 370 and 91/104 on C16 and he's running near about 20 timing with 28 psi. Granted that's C16. He's a frequent plug checker so there is rigor in his process.
Yea I do agree it is probably a bit too hot but I've got no knock and zero signs of detonation on any of my plugs. It runs like a top and pulls like a freight train. I'll end up getting it on the dyno in the spring and get everything optimised.
Yea I do agree it is probably a bit too hot but I've got no knock and zero signs of detonation on any of my plugs. It runs like a top and pulls like a freight train. I'll end up getting it on the dyno in the spring and get everything optimised.
I'd throw a little race gas in it for a safety margin on dyno day, dyno's load the engine different than the street.
What is your compression ratio? If you have rec port heads and forged dished pistons your compression could be like 8.5:1. I think that may be your only saving grace here. This engine by all means should be scattered by now. You have the most timing ive ever seen in low boost and vacuum.
Ive attached a pic of my timing table that I plan on starting with for my 10.8:1CR forged lq9. On pump 93. 7875 turbo. For those not familiar with Kpa, below 100kpa is vacuum, above 100 is boost. 200kpa is 15lbs boost.
These values worked very well on my naturally aspirated setup.(95kpa WOT) Ran 112mph in quarter with super mild cam.
Do you have a very large stall converter? Does the turbo only spool at high rpm?
These two things could reduce load on the engine and allow for more than normal timing, and have you confirmed your timing yet with a timing light?
As others have said, timing just seems very aggressive
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Questions about timing table 
