I bought the SS in May, and had the spray on it in Sept. via a 5177 kit. I wasn't real impressed with the 100 jets, so I stepped up to the 125 pills for the dual nozzel set up. I changed plugs to the TR6's and installed the TransGo so I could spray through the shifts.
Long story short, it broke #6 piston skirt from running lean. The 0s sensors had to be replaced after the piston due to low fuel trims on both banks...like 21-25. Replacing them managed to get the furl trim down to 8-12 on average. The tech at the dealer said it was still a little lean, but may be due to the ported MAF.
What are you all's suggestions for another attempt with the junk, say a 100 wet? Do I need a MAFT, ECM Programming, injectors or what. Should I be nervous of the other 7 pistons that didn't get replaced due to their appearing to be in perfect shape.
Any help or advice would be appreciated.
Kurt

<small>[ November 02, 2002, 10:48 PM: Message edited by: 02 SOM SS ]</small>

 

Hey man,I got a 125 dry shot on my 98 T/A.I got a MAFT and I richen it up 4% and spary the **** out of it and it runs find.Get one and be safe.Last night ran a 7.70 spinning 60's were about 2.00 the best was 1.98.

 

I put a 1oo wet shot on mine. I got a
T-rex fuel pump and 30lb injectors. I had to do this because I put Heads and cam. I would get tuning to adjust timing. I run 23-24 degrees when I spray. That way I`m alittle fat when I spray. Just to be safe! I loose alittle RWHP N/A but I make up for it with TNT. Hope this helps! <img border="0" title="" alt="[Cool]" src="gr_images/icons/cool.gif" />

 

johnster: your 98 has bigger injector then mine doesn't it? I hear ya on the MAFT, I guess the only way to know for sure in dyno tuning huh.

Beard: thanks for the reply! <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

 

The ported MAF ending are a no-no on the juice unless you have made sure your A/F looks good with them.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 4mulaJoe:
<strong>The ported MAF ending are a no-no on the juice unless you have made sure your A/F looks good with them.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Why is that? Seems like the !MAF mod is a killer to the car. My car runs noticably harder with it in place, but first trans line pressure problems now possibly this. I descreened it and ported the u no what out of it. hmmmm.

 

Did you ever go on a dyno with a wideband O2 sensor to check Af ratios on spray? If not did you atleast Atap to read O2 volts? Do you have a FPSS or a fuel gauge?

4mulaJoe is right, MAF ends tend to lean out your AF ratio. Not bad if your already rich. But some cars seem to be leaner than others..then add MAF ends and your too close to the edge...add a dry shot and who knows how bad it could get.

 

My 98 has 28.6 I think in 02 they went back to them.The 99-01 had the 26.0.I think I am not sure.

 

[QUOTE]Originally posted by 383LQ4SS:
[QB]Did you ever go on a dyno with a wideband O2 sensor to check Af ratios on spray? If not did you atleast Atap to read O2 volts? Do you have a FPSS or a fuel gauge?

No...unfortunately I didn't do any of the above. This was my first go round with the NOS, I listened to ALOT of people say it was safe as crap due to the MAF reading and adjusting the fuel and such. I have learned alot alrady since the motor deal. BTW...the motor had 7k on it when this happened. The dealer was still pretty cool. I will not spray it at all again w/o at least A Taping, or dynoing. Our local dyno shut down, so the drive to OKC it a must since Ed Wright doesn't want to do dyno stuff w/o programming. > <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />

 

not sure what could have caused your issue.. ported MAF or not that size of a shot should not have killed the motor.. slagged the cats maybe but not the motor... too much bottle pressure? that would for sure lean it out.. cheezy gas octane? that would kill you too... and what is ed wrong's deal? what a putz... sorry to hear you don't have much choices on a dyno.. stay away from "a" hole ed's tuning though..

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Chicago Z06:
<strong>not sure what could have caused your issue.. ported MAF or not that size of a shot should not have killed the motor.. slagged the cats maybe but not the motor... too much bottle pressure? that would for sure lean it out.. cheezy gas octane? that would kill you too... and what is ed wrong's deal? what a putz... sorry to hear you don't have much choices on a dyno.. stay away from "a" hole ed's tuning though..</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Yeah...Ed shows genuine interest in me at the track, I guess because he is curious how I have gone 12's on motor w/o his HELP and a lid and filter and MAF mod. As far as bottle pressure, that I ran pretty close to 950-1050 since it was easy to drop with the purge. Maybe the gas...I always run 93, but who knows what it really is.
Anyways...thanks for the reply.

 

Yea...just go with the MAFT and fatten it up a little. Dry kits are so unpreditable...I dunno ...relying on the MAF to add fuel just doesnt set right to me. I am a firm believer in wet kits. If you're going to stay with the dry kit then just fatten it up a little, you'll be fine

-Tim

 

If the car is "dialed-in" NA and running big enough injectors at a safe injector duty, the ecm will be able to compensate for the extra "air" from the nitrous....really. Just look at the pulse widths increase corresponding to increased MAF...btw, anything over 20 m/s you need bigger injectors to run safely. FWIW, I run 36#
I had always heard also that you need to lower the timing for nitrous use....nope, the ecm knocks the timing down corresponding to the reduced IAT. This is the great thing about dry systems...the ecm uses the MAFS to monitor and adjust for the existing condition...NA or nitrous. Again I will emphasize this can only happen if the ecm is "tuned" for an optimal A/F. On the other hand, the wet system has to be "dialed" in by trial and error as to jetting combination for the correct A/F. This combination will change with the climate...etc., which could be a problem if not monitored and changed. I would rather feel confident that a computer is tracking that vs. me.
BTW, my tuner (Mark at Raging MS)--------------->>
had my A/F tuned in on a WB and consistantly gives a .90 to .91 NA and N2O....31 max timing NA and 24-26 on the gas. Marks increase on the timing netted me 10hp/10tq... <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
OBTW, the LS1 has a "dry" intake...wet system running too rich will produce puddling and possible...KA BOOM! <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />
Oh ya, almost forgot...when Mark increased the timing he also fattened it up abit. Before tuning I was running 6% lean w/ the MAFT and showing O2's around .86 w/ no KR. Now it is set at 2% rich w/ .91 w/ no KR. It appears the LS1 likes increased timing and enrichment.

Sorry for the rambling. Hope this helps.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by PewterZ:
<strong>Yea...just go with the MAFT and fatten it up a little. Dry kits are so unpreditable...I dunno ...relying on the MAF to add fuel just doesnt set right to me. I am a firm believer in wet kits. If you're going to stay with the dry kit then just fatten it up a little, you'll be fine

-Tim</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I agree.Dry kits are relying on the stock computer too much.I've always recommended wet kits over dry.The ported ends are risky with any Nitrous setup.If you want to play safe install the bigger injectors,pump and have it tuned in with edit.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 02 SOM SS:
<strong> </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 4mulaJoe:
<strong>The ported MAF ending are a no-no on the juice unless you have made sure your A/F looks good with them.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Why is that? Seems like the !MAF mod is a killer to the car. My car runs noticably harder with it in place, but first trans line pressure problems now possibly this. I descreened it and ported the u no what out of it. hmmmm.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Ported MAF = Bad idea on a 2001 or 2002 car, which are on the lean side from the factory. Tests have actually shown little or NO GAIN from a ported MAF on even a big cube car. Secondly, why are you spraying without knowing your A/F ratio. VERY BAD IDEA!!!!

 

Id put money on the ported MAF