[stangfreek94]

Just want to get a better idea, if I'm in the right ballpark. The car feels super strong. It's just sometimes at the top of 3rd and 4th, I get a little hesitation. Not all the time. I think it could prolly use some more timing. Or, a maybe a lil' leaner. Without the meth injection, I see @ 22* at 5200 on up. Haven't really tried to add much more with the meth yet. Only been up to 26* with the meth. I think I've got it set pretty aggressive, just want to compare. My AFR is right around 11.7:1 all the way through. Some spikes to 12.0:1, and down to 11.3:1. I've only been running with the 255 intank. I had some problems trying to keep the base fuel pressure down with the 255 intank & 255 inline, and the stock rails and lines. So, I pulled the fuse on it. The fuel pressure goes up to @ 55 psi. This may also be the hesitation, or I guess it could be a lil' belt slip, or spark. Just curious to see what you guys have for your setup.
I see @ 13-14#s at 5900-6100 rpm, with the stock SQ pulleys on my combo. Logged maf flow of 2,04x, I can't remeber what the voltage was off the top of my head. Something like 4.2 volts.
I can't wait to see what it does this summer. Just got everything running real good. Still trying to get the kams closer to perfect with the slopes, before I mess with the maf curve anymore. So, I can tweec the ISC settings, and the throttle body airflow. I also still have to install my new fuel system, and shocks- struts.
Can you paste a screen shot of your spark tables? Thanks, Joe

[JuiceSC]

26* You got ballz. :D Even 22* is agressive with that much boost. 26* for me resulted in a popped HG. (my own fault, forgot to take out timing) I'm running 18* and it seems to work well with only 8 psi. I *may* try a little more at the Glen this year......maybe.....

[Dale McPeters]

26* You got ballz. :D .

I agree with this statement.......

[stangfreek94]

26* was with the meth. injection. Only tied it twice, and is was recently, with the cold air. So, if I were gonna have any problems. It should be this time of year. You never know what you can do, til' you try it. It runs great at WOT, kinda scary fast. I think the TW heads tend to like more timing than others. Post up some ballsy spark tables.

[89blownssv]

I'm running 24* at wot with 22 lbs boost non intercooled.

using 110 octane fuel.

[JuiceSC]

26* was with the meth. injection. Only tied it twice, and is was recently, with the cold air. So, if I were gonna have any problems. It should be this time of year. You never know what you can do, til' you try it. It runs great at WOT, kinda scary fast. I think the TW heads tend to like more timing than others. Post up some ballsy spark tables.

Ok, I can see 26* with meth.....errrr...methanol. hehehe Your right though, my heads do have the "fast burn" chambers and specifically say not to run more than 28* N/A.

[JuiceSC]

I'm running 24* at wot with 22 lbs boost non intercooled.

using 110 octane fuel.

Thats not fair.

[boss96]

It's just sometimes at the top of 3rd and 4th, I get a little hesitation. Not all the time.

Since you have one fuel pump disconnected I would be very careful. In the higher gears you have more load, or a better way to put it, the load is higher for a longer time due to the gearing.
What is your fuel pressure at the top of 3rd and 4th when you fell the hesitation? You may need to put a better fuel system in, like bigger rails, etc.
As far as timing goes, I can't speak directly for 5.0 motors but I would be conservative using pump gas, you already damaged some pistons recently, why take a chance? Use the 50/50 water/meth mix for more timing, then I feel confident you can add 7-8 degrees more timing from your pump gas tune safely.
BTW, did you replace all the pistons or just the damaged ones? I would do a leakdown test on all cylinders to know for sure the conditon of the motor.
Bob

[Dale McPeters]

Bob, Are you think about Warren when he broke the pistons
in his engine from running to much timing?

[89blownssv]

Thats not fair.

What part is not fair?

the timing?

the boost?

the fuel?

The fact it is all going through a stock shortblock with stock pistons? :o

[JuiceSC]

Thats not fair.

What part is not fair?

the timing?

the boost?

the fuel?

The fact it is all going through a stock shortblock with stock pistons? :o

I was just teasing, but I was refering to fuel. I kinda took his question with pump gas in mind. :D

[boss96]

Bob, Are you think about Warren when he broke the pistons
in his engine from running to much timing?

You're right, Dale, mixed up the cars
Bob

[89blownssv]

I

was just teasing, but I was refering to fuel. I kinda took his question with pump gas in mind.

ok, I agree with your timing specs on pump gas. :)

My combo don't run too good on pump gas.

It detonates and pushes out the headgaskets.

But it really likes the 110. :D

[JuiceSC]

My combo don't run too good on pump gas.

It detonates and pushes out the headgaskets.

But it really likes the 110. :D

I'm thinking 22#s of boost may have something to do with that.... :D

[2Shaker]

Yeah, it was me who burned 3 pistons with 30* of timing and 12 lbs boost. Not a pretty sight. And hot lapping it didn't help as the ACT's were really up there.

I read this thread right away because the motor is back in the car and its time to put more reasonable timing tables in TwEECer.

Dale, BTW, I resent the pictures, were you not able to open?

[stangfreek94]

Guess I'll just stick with what I have been running. It seems to like it. I think the hesitation is prolly a fuel volume problem. I'll have to get to work on getting my new fuel system in as soon as possible. This is with pump gas, if that wasn't clear before.

[stangfreek94]

I'll post up my spark tables sometime this weekend, if I get the chance.

[Dale McPeters]

Dale, BTW, I resent the pictures, were you not able to open?

Warren,

No sir. Something is stripping the pictures out before they even get to
my internet service provider. I will drop you an email with a different email address to try. You should have it after while.

[Shaker666]

Guys, don't forget that you simply don't need that much timing to maximize power output in a blown application. Spark advance in an N/A setup is there to give the combustion enough time to burn properly to make good power; in a blown car, the combustion and flamefront propogation occurs much faster due to boost. Therefore, the more boost you run, the less timing you need to properly synchronize the combustion events.

[Dale McPeters]

Guys, don't forget that you simply don't need that much timing to maximize power output in a blown application. Spark advance in an N/A setup is there to give the combustion enough time to burn properly to make good power; in a blown car, the combustion and flamefront propogation occurs much faster due to boost. Therefore, the more boost you run, the less timing you need to properly synchronize the combustion events.

[SHaFT7]

with my setup, i ended up adding 8 deg everywhere on the spark tables (except WOT, which is signficantly reduced). this was the _only_ way to get rid of the horrendus bucking/popping/stumbling with any load between idle and wot.

do i need to be worried about burning pistons or anything? i'm setup for ~9.4:1 with a powerdyne and 9psi. my afr is under 12.0 at all times during WOT

[Shaker666]

with my setup, i ended up adding 8 deg everywhere on the spark tables (except WOT, which is signficantly reduced). this was the _only_ way to get rid of the horrendus bucking/popping/stumbling with any load between idle and wot.

do i need to be worried about burning pistons or anything? i'm setup for ~9.4:1 with a powerdyne and 9psi. my afr is under 12.0 at all times during WOT

I don't think that adding 8* everywhere is a good idea at all. I would keep the tables stock and try to tune the MAF to resolve your bucking/stumbling problems. I ended up using the stock tables, but reducing the timing by about 20% for the highest load row, 15% for the 2nd highest, and around 8% for the 3rd highest row. I'm 19* at 5000 RPM, WOT. Runs quite well at ~14 psi.

[SHaFT7]

interesting... picked up power in the midrange....

the afr always looks good....

don't aluminum heads need more timing? especially since i'm using 91 octane over stock iron heads with 87?

also, this is only part throttle...wide open still has the timing way reduced for the blower


btw, my roommate with TW heads (57cc at that) stock cam and a HP stage 1 turbo kit had to do roughly the same thing to get the bucking gone and be able to drive around normally

[Shaker666]

I've always attributed bucking to an untuned MAF curve, as has largely been the case in my experience. The timing never had anything to do with it, at least on my car.

[stangfreek94]

All these opinions and advice. I've still not seen 1 spark table yet. Which is what I asked for.

[Cougar5.0]

All these opinions and advice. I've still not seen 1 spark table yet. Which is what I asked for.

Reasons I didn't provide any info:

1. I don't consider my setup to be high power SC
2. You asked for a table then seemed to talk about the WOT spark function
3. My table is stock except for scaling of the Y-axis (load)

FN904A - Sealevel Spark:

___500 700 900 1100 1300 1500 2000 2500 3000 4000
1.00 8 8 9 10 11 13 21 21 21 21
0.80 8 8 9 10 11 14 21 21 21 21
0.66 15 16 16 16 18 20 26 27 27 27
0.52 20 21 25 32 34 34 33 32 28 28
0.38 25 26 30 37 38 36 36 38 28 28
0.24 28 28 33 37 37 38 38 38 28 28
0.10 28 28 28 32 34 35 35 34 28 28
0.05 28 28 28 31 33 34 34 34 34 34

FN131 - WOT Spark Advance Function:

0 1000 1800 2150 2600 3700 5000 6000 6400
8__8__18.5_21.5_22.5__23___26__26___0

I also have meth injection but I rarely get that WOT spark due to FN135 settings:

FN135 - WOT Spark Advance vs. ACT

-256 120 150 180 210 240 254
__0__0___0__-1_-3__-6__-10_

[stangfreek94]

Mine's pretty similar. (CBAZA)I don't have access to the WOT spark advance function though. I do have spark advance rate vs RPM, but it's some kind of multiplier. I really just wanted to get some ideas, of what everyone else was running. Thanks for posting it up.

[db1994]

Most all the turbo/intercooler guys I know (including myself) run 21 degrees total under full boost/load at anywhere from 6-15psi and seem to have pretty good success with it using pump gas.

What you can get away with is typically inversely proportianate to your ACT - which you didnt post.

-Jason

[Shaker666]

Most all the turbo/intercooler guys I know (including myself) run 21 degrees total under full boost/load at anywhere from 6-15psi and seem to have pretty good success with it using pump gas.

What you can get away with is typically inversely proportianate to your ACT - which you didnt post.

-Jason

This is true, but you need to also be aware of your existing compression ratio - what it really is, not what you think it is.

[SHaFT7]

ok, my WOT timing tables go from 24 down to like 18....so i have THAT covered.

using the 03 Cobra maf curve out of EA, I pretty much don't have to touch it at all using my LMAF. everything is within the KAMRF's range to correct. with the bucking/stumbling still there, that points to timing. adding the degrees helped 150%. (i even tried a race plug, which helped some, then the computer learned its way around it). with the timing, it is good all over the place. (there are a couple spots i need to fine tune, but 98% of the table is great)

with the wideband showing correct, and no red flags showing, i think this is what my car just wants.

91 octane, box stock TW heads, b-31 cam, and a powerdyne @ 10psi