Has anyone experienced more power with upping the timing past 22* on small turbos and pump gas? With an estimated 11.5x A/F ratio and 22* peak timing, DSMLink is estimating 276awhp at 16PSI. When I was running a tad richer, I tried upping the timing, and simply got a little more knock and no more power. On the other hand, leaning it out an additional 2% netted an esimtaed ~5awhp gain.

Can any more power be had by bumping up timing and adjusting fuel where neccessary?

I will not up the PSI. The turbo is a friend's, and I see no reason to kill it.

Any thoughts on this topic? I've included a DSMLink log.

spammer!

rsTurboLaser said:

spammer!

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Wtf? Wrong thread?

The general concensus is that once A/F is in target range (say 11-11.5:1 on pump), you would want to add boost and remove timing as needed since pump doesn't have the knock suppression capacities of race gas. Here's how I would do it:

1. Set A/F to target
2. Log for best airflow at a given boost level
3. Once optimal airflow is achieved, add timing
4. Tune for 3 counts of knock at the top of third.

The long and short of it is that boost will make more power than timing on pump gas. Try the above steps and let us know where you stand.

Hope that helps,

Andy

Edit: I just re-read your post and noticed that you don't want to up the boost. You can try taking away more fuel, but timing at 22 is right about where you want to be. Try leaning out to 11.7-11.8 and see if it makes more power.

aero_sallee said:

Wtf? Wrong thread?

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Friend of mine passing through, don't mind him.

andymoraitis said:

The general concensus is that once A/F is in target range (say 11-11.5:1 on pump), you would want to add boost and remove timing as needed since pump doesn't have the knock suppression capacities of race gas. Here's how I would do it:

1. Set A/F to target
2. Log for best airflow at a given boost level
3. Once optimal airflow is achieved, add timing
4. Tune for 3 counts of knock at the top of third.

The long and short of it is that boost will make more power than timing on pump gas. Try the above steps and let us know where you stand.

Hope that helps,

Andy

Edit: I just re-read your post and noticed that you don't want to up the boost. You can try taking away more fuel, but timing at 22 is right about where you want to be. Try leaning out to 11.7-11.8 and see if it makes more power.

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Didn't really answer my question, but thanks. I'm well aware of how to set up fuel and timing maps.

I was more interested to know if people are sucessfully pushing past 22*, because I'm pretty sure I've hit the limit of the 14b given my setup.

Coup D E'Tat said:

With an estimated 11.5x A/F ratio and 22* peak timing, DSMLink is estimating 276awhp at 16PSI. When I was running a tad richer, I tried upping the timing, and simply got a little more knock and no more power. On the other hand, leaning it out an additional 2% netted an esimtaed ~5awhp gain.

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According to Corky Bell's Maximum Boost, a turbocharger does a good job of churning up the mix and bringing it to a higher energy state. This is one reason why we get horsepower when we advance timing. But, if you already have your gasses in the combustion chamber churning up pretty good because of the added dynamic compression and pressure from a turbo, then you get diminishing returns earlier when advancing timing and yielding more power. But you'll stll linearly(somewhat) increase your likely hood of knock. According to dsmlink, I made not much more power from advancing my timing beyond 25* w/ my 18g at 25 psi. +25* timing nademe nervous . I was getting no knock but because I was running water injection. Realizing this, instead, I raised boost 3 more psi and gained about 25 hp according to dsmink. . . I cannot find my logs. It's probably still on the wife's laptop .

Whether or not 22*-24* is the limit of good returns is primarily based on whether or not you get knock before this. If you're getting knock before this then, obviously, you can't get any more returns for advancing the timing... I know you know this, but with this point of view Andy answered your question rather well, IMHO . You tried to up the timing and only got knock this is your limit on your setup unless you richen up. This can only be experimented. Try richening to 10.5:1 and see if you can get away w/ more timing. Then see if this yeilds more horsepower w/ dsmlink. Since you're getting significant knock beyond 22*, you can do is try to get better "knock inhibitors": better intercooler, water injection, etc. These would let you keep your a/f ratio where it is, which is great. Or increase both timing and a/f ratio (12.5:1 - 13.5:1 or so offers the most hp/volume). Either way, this would help you get more out of the 14b if you so choose.

I have one of the best intercoolers on the market IMHO, and don't feel the need yet for water/meth.

That said, I know it's more of a trial and error situation, but like I said, I was looking for other user's experiences. I wouldn't call the knock I received "significant," but no more power was made, which is why I didn't go any farther. Looking back, I should've richened it a tad to see what happened, buy eh, I have a few more weeks with the 14b to play with.

Coup D E'Tat said:

I have one of the best intercoolers on the market IMHO, and don't feel the need yet for water/meth.

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Coup D E'Tat said:

I wouldn't call the knock I received "significant," but no more power was made, which is why I didn't go any farther.

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Awesome then you're prety much done . It's good to se 22* timing w/ no significant knock and running +11.5:1. You've gone as far as one can, IMO.

Coup D E'Tat said:

I have one of the best intercoolers on the market IMHO

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Who makes it, what are the core dimensions, and more importantly, how much does it flow?

There isn't a whole lot you can do with liquid detonation, eerrrrr, I mean pump gas. Its not too hard to run 25psi on pump with a good setup, but I definitely wouldn't stretch 4th gear. From my experience, timing doesn't seem to be real important on pump up after 22* or so. Seems I get more power out of boost increase or getting the A/F exactly how I want it throughout the powerband. On smaller turbos, if I have the ability, I will pull out more timing than usual when boost comes in to control spike and then increase it up top so you don't get that "throw you in your seat then lunge forward" feeling from the spike and fall of boost, but I normally keep it around 22-23 degrees of total timing up top.

dsm-onster said:

if you already have your gasses in the combustion chamber churning up pretty good because of the added dynamic compression and pressure from a turbo

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Matt, what added dynamic compression are you speaking of here?

1SloColt said:

Who makes it, what are the core dimensions, and more importantly, how much does it flow?

There isn't a whole lot you can do with liquid detonation, eerrrrr, I mean pump gas. Its not too hard to run 25psi on pump with a good setup, but I definitely wouldn't stretch 4th gear. From my experience, timing doesn't seem to be real important on pump up after 22* or so. Seems I get more power out of boost increase or getting the A/F exactly how I want it throughout the powerband. On smaller turbos, if I have the ability, I will pull out more timing than usual when boost comes in to control spike and then increase it up top so you don't get that "throw you in your seat then lunge forward" feeling from the spike and fall of boost, but I normally keep it around 22-23 degrees of total timing up top.


Matt, what added dynamic compression are you speaking of here?

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Dynamic Compression Ratio Calculator

1Slocolt, were you running pump gas at your last dyno session? You pulled out over 400whp, right? What is the jist of your timing curve, pump vs. other (if you ran other)?

1SloColt said:

Who makes it, what are the core dimensions, and more importantly, how much does it flow?

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Garrett 24x12x3.5, VPE end tanks, model number 703520-6005, rated at 925HP, couldn't find any flow numbers on it, but I trust Garrett

There isn't a whole lot you can do with liquid detonation, eerrrrr, I mean pump gas. Its not too hard to run 25psi on pump with a good setup, but I definitely wouldn't stretch 4th gear. From my experience, timing doesn't seem to be real important on pump up after 22* or so. Seems I get more power out of boost increase or getting the A/F exactly how I want it throughout the powerband. On smaller turbos, if I have the ability, I will pull out more timing than usual when boost comes in to control spike and then increase it up top so you don't get that "throw you in your seat then lunge forward" feeling from the spike and fall of boost, but I normally keep it around 22-23 degrees of total timing up top.

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This was more along the lines of what I was looking for in an answer, thanks a lot

EDIT : If I get the chance within the next few days, I'll play with the timing and fuel maps a bit and see if I can squeeze some more of out my setup. I'll report back with my findings.

dsm-onster said:

Dynamic Compression Ratio Calculator

1Slocolt, were you running pump gas at your last dyno session? You pulled out over 400whp, right? What is the jist of your timing curve, pump vs. other (if you ran other)?

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Thanks for the link but I already know how to calculate dynamic compression, I just didn't know where you were coming from about the dynamic compression in a previous post is all, my stupidity, though I still don't, . My car has actually never been on the dyno. I'll be on the dyno saturday at promotion as they are having another shootout, 2 pulls with wideband for $25. Last time we had a shootout we put 29 cars on the dyno in about 6hrs, . I don't see any reason why the car shouldn't make 400whp, but you never know. It was definitely flowing enough air for 400whp the last time it was on the street.