Hummmmm.......

Best Tune so Far, Map 12 (491/404) AFR's 11.0 to 11.20 in upper boost

Lost Power..........Map 14 (464/383) AFR's 11.35 to 11.75 in upper boost
Leaned it out .03 to .05 thru out the Boost Range, Loss of power and tq is consistent.

Oustside condition the same, 90-94* Hi Humidity

Ignition Timing Unchanged

When I loged Map 14, it did not feel quit as strong, did not have the same ***** as Map 12, when I thought this thing was Really starting to Run like a raped ape.....then when I got home it was confirmed...... I know it will very from one run to the next, but this much?

Is it just that this motor like 11.0's to 11.20's in boost? OR?

 

that's odd. I would assume going to mid 11's would increase the power.

 

I have a stock vortech setup with the 2.87 and everything you have exhaustwise except the headers. I am only making about 10-11 psi, Does dropping two teeth off the cog raise boost by about 5 psi? I see you have a larger intercooler do you think that is a bottleneck of the stock vortech system?Does your 12x4x24 intercooler fit under a stock bumper. These kind of gains on a stock block are making me consider doing what you did and getting a re-tune. I wonder if my 600cc injectors could keep up with another 40whp....

 

I made 12 psi with the 2.87, 32/28 cog and stock rev limiter
1 made 14 psi by reving to 7100 rpm
added intercooler, 15 psi
added 34/28 cog, 16 psi

it may be a bit higher that 16psi, but that is the lim it of my tools......

with a bigger the intercooler, you'll get less pressure drop and cooler Intake Temps.

stock vortech intercooler is rated @ about 700 cfm and 550hp
new intercooler rated at 1200 cfm and 900 hp

 

When are you gonna go back to the track and see how it compares to your old no's.

 

Late Oct, Nov......when it cools down. it is this above 90* here in florida, with very high humidity....

 

Guys on YellowBullet.com ( a drag racing fourm ) ( very good info ) seam to think that in Map 14, I may be getting knock and ecu is pulling timing

My timing map is as follows:

-5* @ 5.0 psi
-7* @ 8.0 psi
-8* @ 10.0* psi
-9* @ 12.0 psi
-11* @ 13.0 psi
-12* @ 14, 15, 16 psi

 

12* is pretty low but it could be possible. I always used meth and was running 16 or 17* timing with no problem.

 

those numbers he listed is how much down from the stock timing he is pulling.

Tim, we need to know what the oem ecu timing is to get a good calculation. I want to think when i was doing scotts the ecu was pushing around 26* timing nearing 6600 rpms. I logged oem timing then i adjusted that at each rpm range with the amount i have set to pull. THe oem timing varies sometimes from pull to pull because the ecu is trying to advance it. Sometimes it's 23* in midrange and others 24* in midrange.


what is leading these guys to believe it's pulling timing? logging timing is the easiest way to tell.

 

One thing I experinced with my car with my tuner was that I would get false knock readings which with prompt the ECU to pull timing...so for one of my Osiris tunes we just turned off the ECU knock sensor...

But this is with a noisy built engine, I don't remember having this issue with the stock block...

 

My timing map is as follows:

23*-5*= 18 @ 5.0 psi
22*-7*= 15 @ 8.0 psi
24*-8*= 16 @ 10.0* psi
28*-9*= 19 @ 12.0 psi
29*-11*=18 @ 13.0 psi
30*-12*=18 @ 14, 15, 16 psi

I loged timing yesterday, with Map 12, ECU was not pulling timing.

 

so ya 18* total timing is pretty aggressive. thats not the problem.

you car just likes those AFR better

 

Also Loged IAT's Max Temp was 109* F, during pull went up about 1* per 1 pound of Boost. How does this compare to others?

 

109c is very hot. Are you perhaps logging in f?

 

I'm sure he means degrees.

 

109* f isn't too bad Tim

With my new large intercooler on my large turbo i'm seeing about a 20* raise in temperature over ambient on a 3rd gear pull at 16psi of boost. I'm not sure what HP this would be on my car but for a reference 13psi was 523hp with less timing than i'm running now.

I agree that the timing seems a little aggressive up top but as long as it's not pulling timing when you look at the oem map then it's not detecting any knock. Every engine is different so yours is just less prone to detonation then others probably.

 

Ya, it was about 90* ambient with IAT's @ 109*.

I loged Timing, no signs of ecu pulling timing, but backed it of 1* anyway.

It's just strange that one run would Feel so Good and log reflected it, then next run with very little change ( -0.1 in some areas and -0.2 at just 13.5psi) could feel the power off a little. Seams better with -1* timing.

Another Issue

Under almost no throttle at all, say 1900-2200rpm 3rd gear low cruise.
transition in and out of Decel is not very smooth. What is the secret here? Driving me crazy......

 

is this all street tuning? wouldn't it be best if you could verify your changes via a dyno?

 

Yes and No.........

A Dyno is only Good if you have an Expert Tuner that will Tune All Aspects of the Map, not just WOT..... Just because some guy has a shop with a dyno means nothing to me. and on top of that charge you $125 an Hr......

A Full Tune IMO consist of Dyno time and street tuning for drivability.......

IMO, Drivability is far more Important than Max Hp Number, But I want the Best of Both Worlds.

I have a good Feel for how the Car is Running plus I have an Accelerometer that gives me the numbers for verification.....

After Street Tuning, the Drag Strip is also a good way to Verify the Tune.

 

well, my only qualms about your power production were verifying any changes actually made more or less power - butt dyno's can be fairly inacurate. i wasn't trying to knock your tuning abilities. you could possibly bang out a power tuning on a dyno in a couple hours, i know around me you can just rent the dyno and do your own wot/power tuning...and then you can complete drivability on the street.

i didn't realize you were using an accelerometer, that will for sure help. good luck, i'm interested to see your track results!