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GM blends MAF/VE before 4,000 rpms and all MAF after.Quote:
i was under the impression that MAF will not kick in anywhere before 4k rpm,, or you enabled it for the entire rpm?
Motion is if idles fine in SD and not in MAF mode I would suggest its fueling related b/c that is the only variable that's changing.
That must be the problem.
I asked when he's ready,I'll take another look at it.
Recheck my work,and hopefully I'll find something.He says it run's perfect,but I know I can do better with the idle for sure.
Thanks again.
I compared the tune with a stock one,and I think it must be the MAF tuning.
I removed 18-20 points from the VE table at idle,and I did not remove anything from the MAF in the area of 2500-3000Hz.
So it looks like I need to do a little work in that area,but I'll recheck the VE.
Great Info.
Hey everyone, newbie here. Been reading a lot on tuning and have a lot to learn. I have 2 questions about this post for Rinkrat456, or anyone experienced for that matter, that I am hoping can be answered so I don't screw anything up.
#1: Can you please clarify the step where you talk about "add 2º of idle timing 1200 rpm and under and 0.08 – 0.28 g/cyl inclusive (HPT > Engine > Spark Control > Spark Advance > Idle Spark Advance (in Park)."
The reference picture shows the "Low Octane" table. Can you verify for me if it should be the "Low Octane" table that I need to change in this step or the "Idle Spark Advance (in park)" table?
#2: Can you please clarify the step where you talk about "Make sure that your Idle Spark Advance table (both “In Drive” and “In Park”) match your High and Low Octane Table for all columns up to 1200rpm (HPT > Engine > Spark Control > Spark Advance > Idle Spark Advance (in Park, in Gear), Hi and Lo Octane)."
Can you please elaborate a bit more for me? Should I copy the "in park" table over to the "in drive, low octane, & high octane"? Should all 4 tables match exactly up to 1200 rpm's for all columns or just 0.8 - 0.28 g/cyl?
Sorry for the stupid questions but I really want to get this right the first time. Thanks in advance for any help!
questions are never stupid,,Quote:
Originally Posted by priest01ss
you just replied your own questions though,,
Thanks kj217 but I'm not sure what you mean by I replied to my own questions?Quote:
Originally Posted by kj217
"Should all 4 tables match exactly up to 1200 rpm's for all columns or just 0.8 - 0.28 g/cyl?"
they only need to match in idle area,, not for all the columns,,
What about all of the rows? Should all 4 tables in the idle area match exactly for all rows (g/cyl) or just from 0.8 thru 0.28 g/cyl?Quote:
Originally Posted by kj217
just from 0.8 thru 0.28 g/cyl?
Ok so I followed the setup exactly and attached are the numbers I came up with on the first startup scan.
Temp: 68_____90_____111____133___154____176___198___219_ __241
g/cyl: 21.19__17.94___16.86__14.24__10.51___3.47__2.99__2 .88___2.87
- Do these numbers seem normal?
- What would be considered high or low g/cyl numbers?
I'm not sure if I want to just paste these numbers straight over unless I know it won't cause any strange idle problems. I'm going to check all of the settings again and run another startup scan. In the mean time, can someone let me know what they think? Thanks!
From 176 up to 241 your RAF values are quite small, smaller than stock I would say. Have you changed the Throttle Body? Which engine, which TB?
I thought they seemed quite low and I was surprised at the huge g/cyl drop from temps 154-176.Quote:
Originally Posted by Pekka_Perkeles
The intake and TB are FAST 92/92 with an 85mm SLP MAF and an 98mm FTP lid with a stock filter.
The intake runners were port matched to the TEA Stage 3 5.3L heads (I do not have all of the specs on the heads, were on the car when I purchased it).
It is a stock internal LS1 with the exception of the Futral F12-114 (230/230, .595/.595, 114LSA) cam.
Also have Pacesetter LT's with a TX Speed catted Y-pipe & SLP LMII w/Poweflo cat-back.
Injectors are SVO/Ford 30lbs (approx 36lbs on car) with Racetronix F99 Fuel Pump kit.
Deleted A.I.R. & A/C. Still using stock narrowband O2's until I can get bungs installed for the Innovate LMII.
Any thoughts?
Thanks!
If you think that you now have a bigger TB than stock, would it need to open more or less, if the engine would be stock? Less of course with bigger TB, to have same airflow at idle.
On the other hand, it is typical that with an engine having a healthy cam, the engine needs more idle airflow to run.
Is this with cable TB? If so, I'm really not an expert in that area.
Yes it is a cable TB.Quote:
Originally Posted by Pekka_Perkeles
How is your iac counts?
How does the guide apply when running speed density and the engine is in a Mazda rx7 with no speed sensor or gear indicator?
I notice it's commonly suggested to match the main spark tables with the idle spark tables. However in Greg Banish's DVD, he says something like the idle spark tables are intentionally much lower than the main spark tables to allow the over/under speed table to work? If this is the case, why are we matching spark values? Doesn't this cause us to lose any idle spark control?
Don't confuse Gen 3 strategies with Gen 4, they are quite different in some aspects and timing is one of them.
Quote:
Originally Posted by onspeed
This.. But also keep in mind the stock timing tables alone can cause an idle stall issue or surging. Plus, if you match up all the tables then going from idle to driving will be a good smooth transition. I always match up my main timing table with the idle ones. And I always keep the same timing from about 1200 rpm down, which is typically 18*. Even big cammed rigs, with this method, timing may only vary maybe 1* at idle and the idle is consistent. Of course there is more to it than this, but....Quote:
Originally Posted by SSUte01