How much to adjust injector timing after youve put a turbo on an NA engine? (1 Viewer)

[advlars]

Hey guys.

I posted this question up in my build thread, but figured Id post here so it might get some views from people who know a thing or two about turbos but arent following my build.

Sooo... How significantly do I need to retard the timing once Ive added a turbo? With all the extra heat and air, Im concerned about thermally advancing the timing and causing pre-detonation.

My 3 liter 5l has a 22.2:1 compression ratio and I will probably run 8-10 pounds of boost with an intercooler.

Here are the injector measurements for the FSM including a comparison for the 2L and 2LT:



If Im reading this correctly, it looks like the 2lt is retarded by about .10 mm compared to the 2l?

Should I retard my 5lt by about the same amount? Or should I set it to the most retarded end of the FSM's spec range? More because of the higher CR?

 

[gerg]

Without any other info I'd say using the 2lt as a guide is a great idea.

 

[advlars]

Ok. So my timing tool showed up, and I figured out a way to wiggle it in through the injector hoses and starter motor etc. I wedged the acsd with a 10mm spacer (i used an m10 bolt shaft) per FSM and measured my plunger at TDC. So far, so good, but Ive got myself a bit confused after doing more reading and youtubing.

Bigger number means more advanced right? and smaller number means more retarded? And if thats the case, is my assumption comparing the 2L vs 2lt specs totally flawed? I was comparing the 2L w/acsd specs, cause I *think* all the 2LTs had an acsd (mine did, and all the pictures Ive seen of others do) when I saw a difference of about .10mm. But if im understanding things correctly does that mean the 2lt is actually running more advanced than the 2L?

Fwiw I got a reading of .62 on my engine. Ive got acsd, so it looks to be a bit too far advanced even for an NA 5L as it is?