RUF SS

Ok, tuning was done buy LS1Edit and the O2's for reading. I took my car to the dyno and it did great! 450 rwhp and 447 rwtq. But, my A/F was about 11.8 and gets worse near 5000 to 5500 and comes back to about 11.8 again. However, the power did not drop @ 5000-5500 range.

The car drives great. But I want to know if there is more rwhp in the car if the A/F was @ 12.5 or so? And if so, how much more?

Thanks!

Colonel

From 11.8 to 12.9 I'll guess you pick up 15 RHWP. Just a guess.

What were your O2 readings at 11.8? Thanks. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

RUF SS

Thanks for the reply!

Well, I had MTI do the tuning. They did it based on the O2. But when I put it on a dyno with a wideband it showed about 11.8. I think they use the MAF method to lean out the mixture because I saw the same drop in the wideband graph after the tuning as I did before (from about 5000 rpm to about 5500. but then it goes up to about 11.8 again). I will try to fix that drop too! I have LS1Edit now!!!

If I get about 15 rwhp more or even 10 rwhp more, I will be very pleased!!

Do you know which method I should use to bring things up to 12.5-12.8?

Thanks!

NoGo

iTrader: (2)

Use the PE table. Reduce the PE table by 1%.

The dip in your a/f at 5000 rpms is consistant with every other LS1 out there. I call it the "PCM Gut Check". It is the point in which your PCM decides to richen up the mixture or not to protect the CATS. Oddly enough, even with the COT turned off, it will still do this dip.

Good Luck,
Kevin

niphilli

From what I have read lately the WOT o2 readings are not all that accurate to tune by. You can roughly dial in your A/F ratio using ATAP/Edit/ and your o2s. I think most are shooting for an avg. o2 reading of .89-.91 (mine ended up higher). Again this can vary quite a bit from car to car. The best mothod is always to do your edit changes on a dyno with Wideband. Take note of your o2 readings with ATAP and see what they correlate to in wideband readings incese you ever have to do some tweaking down the road.

-Nick

RUF SS

Thanks!

I will try that!!

John B

iTrader: (10)

Do you have the CAT over temp still enabled? This caused an overly rich condition like you describe on my car. Once I disabled this feature (since I don't run CAT's) and tweaked my A/F from ~11.9:1 to 13.0:1 I picked up ~12RWHP!!!

I wonder why MTI changed the MAF settings....this doesn't sound right at all. The PE vs. RPM is where the changes should have been made for WOT.

Do you know what your timing is in this RPM range at WOT? You may want to tweak this a bit too (either up or down). I actually found my besat power pulling timing a bit back to 27° and leaning it to 13:1. I've made close to 50 dyno runs and tweaked my A/F and timing in 1° increments so I have a pretty good idea of what works on my car but then every motor is different, especially in your case since you have a big beast!

RUF SS

John B,

Thanks for the reply.

I do not know what MTI did, but my old dynos with cats had the same dip. Now I have no cats and after tuning I I still have the same dip. So, I assumed that MTI has changed the MAF setting by %. After I hook up my LS1edit I will see what is changed tonight.

"CAT over temp." what is that? and how would you fix it?

Thanks!!

RUF SS

Thanks!!

NoGo, how would I do that exactly? Should I 101% to decrease it by 1%?

Thanks!

NoGo

iTrader: (2)

Multiply your PE table by 99 and see where that takes you. If it isn't high enough try multiplying it by 99 again.

Most setups take a 2-3% change to move the a/f 1 point.

Good Luck,
Kevin

bo0oost

My heads/cam combo dyno'd 448rwhp with a 12.8:1 A/F ratio.... it peaked HP at 6800rpm.

At 12.8:1, my o2s were reading .98. However, STFT, LTFT was ~0.

DG Gordon

Ok so how much more power can I make with better tuning. I had 11.5 to 12 at 2500 rpms but dropped to 11 down to 10 by 6600rpms. I only gained 8 rwhp with thecam and headers.

John B

iTrader: (10)

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif"> "CAT over temp." what is that? and how would you fix it?
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">There is a tab in the "engine calibration" section and a folder called "test parameters" that has a box in the lower right hand corner. Simply select where it says COT Enabled and put the check mark next to "False".

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Ok so how much more power can I make with better tuning. I had 11.5 to 12 at 2500 rpms but dropped to 11 down to 10 by 6600rpms </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">When I just turned off the COT feature I immediately saw ~12RWHP and my A/F was about 11.9:1. Yo may want to tweak your timing a bit in addition to just getting the A/F correct.

RUF SS

Thanks!!

I will try it out and see if I get some more power! I will be happy with 10 rwhp more!

RUF SS

cool!
I was going to try to put the A/F between 12 and 12.5

John B

iTrader: (10)

You're welcome!

Oh, one more thing.....I found that if I made my A/F 12.5:1 at the peak RWTQ RPM that this made the most torque. I actually gained 5 RWTQ by going from 13:1 to ~12.5:1 at the peak RWTQ RPM. You may want to try this too.