Dyno'd car after SLP LT install - HELP!!!!
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From: Rochester, Michigan
Dyno'd car after SLP LT install - HELP!!!! Three of us went to the dyno today. A buddy with a 2002 Z06, my buddy with the 2001 Cobra and me. The Z06 dyno'd at 355.8 rwhp and 347.4 lb ft of torque. It was bone stock.
The only change in the Cobra since the last dyno run was the installation of BBK long tube headers, and a new cat back system, including a new h pipe, and flow master mufflers. Previous dyno was 291.2 rwhp. This time, 313.2 rwhp. Nice increase huh.
Now for the question. Last dyno for me was 333.5 rwhp and 348.3 lb ft of torque. Since then, I have put on the SLP LT's, the new dual dual slp cat back system, Thunder Racing ported maf ends and a maft. I have autotapped this thing to death!!!! . Thought it was running pretty good. 5 pulls today, lowest, 333.2 rwhp, 349 lb ft of torque. Best was 335.3 rwhp and 346.8 lb ft of torque. Now I'm wondering wtf I spent all that money on just to gain 1.8 rwhp. I talked to somebody at SLP Troy today, and I kinda feel blown off. Doesn't make sense that the Cobra goes up 22 rwhp and I get 2. Can anybody summize why the rwhp did not go up any more that what it did? I'm depressed.
The only change in the Cobra since the last dyno run was the installation of BBK long tube headers, and a new cat back system, including a new h pipe, and flow master mufflers. Previous dyno was 291.2 rwhp. This time, 313.2 rwhp. Nice increase huh.
Now for the question. Last dyno for me was 333.5 rwhp and 348.3 lb ft of torque. Since then, I have put on the SLP LT's, the new dual dual slp cat back system, Thunder Racing ported maf ends and a maft. I have autotapped this thing to death!!!! . Thought it was running pretty good. 5 pulls today, lowest, 333.2 rwhp, 349 lb ft of torque. Best was 335.3 rwhp and 346.8 lb ft of torque. Now I'm wondering wtf I spent all that money on just to gain 1.8 rwhp. I talked to somebody at SLP Troy today, and I kinda feel blown off. Doesn't make sense that the Cobra goes up 22 rwhp and I get 2. Can anybody summize why the rwhp did not go up any more that what it did? I'm depressed.
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Re: Dyno'd car after SLP LT install - HELP!!!! From what I understand, autotap is just a scanner, its LS1Edit that is the tuner.. so did you see anything when using autotap? maybe it needs to be adjusted with edit, or even an HPP3/MAFT?
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Re: Dyno'd car after SLP LT install - HELP!!!! </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by pulszar:
<strong>From what I understand, autotap is just a scanner, its LS1Edit that is the tuner.. so did you see anything when using autotap? maybe it needs to be adjusted with edit, or even an HPP3/MAFT?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">For the last month, I have run autotap constantly and adjusted the maft accordingly. At wot, the o2's were averaging .90 to .91. Today, when we adjusted the maft during the pulls, the hp went from 335 to 333, so, i put it back and it ran 335 again. The a/f ratio is was at 12.2. At normal, driving, the ltft's were at -1 to -.69. No knock retard at all. Like I said, it looks like in autotap, everything is fine. I just don't understand why only 1.8 increase in rwhp. I talked to somebody today at SLP and really got blown off. He said that with the new catback and the lt's, it should have really gone up, that something could have been wrong with the dyno. Not likely, like I said, the Cobra went up 22 which I really expected, but I really expected a whole lot more than this and I expected a little help from SLP, to which I got NONE!!!
<strong>From what I understand, autotap is just a scanner, its LS1Edit that is the tuner.. so did you see anything when using autotap? maybe it needs to be adjusted with edit, or even an HPP3/MAFT?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">For the last month, I have run autotap constantly and adjusted the maft accordingly. At wot, the o2's were averaging .90 to .91. Today, when we adjusted the maft during the pulls, the hp went from 335 to 333, so, i put it back and it ran 335 again. The a/f ratio is was at 12.2. At normal, driving, the ltft's were at -1 to -.69. No knock retard at all. Like I said, it looks like in autotap, everything is fine. I just don't understand why only 1.8 increase in rwhp. I talked to somebody today at SLP and really got blown off. He said that with the new catback and the lt's, it should have really gone up, that something could have been wrong with the dyno. Not likely, like I said, the Cobra went up 22 which I really expected, but I really expected a whole lot more than this and I expected a little help from SLP, to which I got NONE!!!
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From: Santa Clarita, CA
Re: Dyno'd car after SLP LT install - HELP!!!! 333 rwhp seems very nice as well as almost a 112 trap speed when all you have done on allowing more air into the motor is a lid. Am I missing something here? I hope my car will respond that nicely to a lid (free flowing airbox or whatever), as I already have a GMMG, and think the headers are really for higher horsepower applications anyways. I would be happy with your results. I might have chosen a higher lift cam before the headers, but alas I don't have any money to put into my car anyway. Good luck with the ride.
Regards,
Regards,
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Re: Dyno'd car after SLP LT install - HELP!!!! </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by ArcticFormula:
<strong>333 rwhp seems very nice as well as almost a 112 trap speed when all you have done on allowing more air into the motor is a lid. Am I missing something here? I hope my car will respond that nicely to a lid (free flowing airbox or whatever), as I already have a GMMG, and think the headers are really for higher horsepower applications anyways. I would be happy with your results. I might have chosen a higher lift cam before the headers, but alas I don't have any money to put into my car anyway. Good luck with the ride.
Regards,</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">No, your not missing anything at all. I was real happy with the 333, I was just expecting more when you spend $2400 for headers, cats, cat back and installation. I got 1.8. I guess I wouldn't have felt so bad if I had seen the same results with the Cobra, but he put an additional 22 hp to the rear wheels with just the same thing, headers and new cat back system. That's the problem I guess.
<strong>333 rwhp seems very nice as well as almost a 112 trap speed when all you have done on allowing more air into the motor is a lid. Am I missing something here? I hope my car will respond that nicely to a lid (free flowing airbox or whatever), as I already have a GMMG, and think the headers are really for higher horsepower applications anyways. I would be happy with your results. I might have chosen a higher lift cam before the headers, but alas I don't have any money to put into my car anyway. Good luck with the ride.
Regards,</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">No, your not missing anything at all. I was real happy with the 333, I was just expecting more when you spend $2400 for headers, cats, cat back and installation. I got 1.8. I guess I wouldn't have felt so bad if I had seen the same results with the Cobra, but he put an additional 22 hp to the rear wheels with just the same thing, headers and new cat back system. That's the problem I guess.
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From: Santa Clarita, CA
Re: Dyno'd car after SLP LT install - HELP!!!! SS125 your car had 111 mph trap speeds with a basically stock exhaust and lid. That is awesome. I had a Turbo Trans AM I sold to get my 02 Formula and all I can say is that seat of the pants the Formula with its A4 would trap around 100 in this summer weather. You are set for letting a little more air into that thing with the adjustible maft, I think the injectors should be up to it, but I am new to these cars. If you picked up another 20 rear wheel horsepower on top of the previous 333 you dynoed (like the mustang) you would be making 353 rwhp, which like you mentioned is Z06 territory. I don't believe the newer f-bods with exhaust modifications are a Z06 car, but I guess there are factory freaks.
Regards,
Regards,
Re: Dyno'd car after SLP LT install - HELP!!!! You need to lean the car out! A 12.2:1 a/f ratio is pretty rich, and you'll find your power in a leaner a/f ratio. I'd target 12.7-12.8:1 if it was me. That would still be safe and help you find your power.
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Re: Dyno'd car after SLP LT install - HELP!!!! </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Trevor D:
<strong>You need to lean the car out! A 12.2:1 a/f ratio is pretty rich, and you'll find your power in a leaner a/f ratio. I'd target 12.7-12.8:1 if it was me. That would still be safe and help you find your power.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">What Trevor D said, you're running really rich. I would guess moving the MAFT switches to 4% leaner at WOT will put you in the ballpark for optimum performance.
<strong>You need to lean the car out! A 12.2:1 a/f ratio is pretty rich, and you'll find your power in a leaner a/f ratio. I'd target 12.7-12.8:1 if it was me. That would still be safe and help you find your power.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">What Trevor D said, you're running really rich. I would guess moving the MAFT switches to 4% leaner at WOT will put you in the ballpark for optimum performance.
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From: TEXAS
Re: Dyno'd car after SLP LT install - HELP!!!! Did you use the same dyno? and were both numbers SAE corrected? Did you disconnect your battery so the PCM can re-learn? After I got done installing SLP LT, my dyno increased 25 hp and 23 trq. That was with out even playing with the MAFT. Now that it is tuned, I hope it would increase a little more.
PS. I have not been able to run it at the track yet, so I don't know any et/mph increases.
PS. I have not been able to run it at the track yet, so I don't know any et/mph increases.
Launching!
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From: Podunk, VA
Re: Dyno'd car after SLP LT install - HELP!!!! Probably your converters are the bottleneck. Stock GM converters are somewhat restrictive (from what ive learned).
I used to have a DOHC Cobra and I know the converters on those are pretty free-flow. That could explain the big gain for the Cobra.
Im sure also your A/F ratio is messed up also. Your 02 sensors are not that accurate unless on WOT.
I used to have a DOHC Cobra and I know the converters on those are pretty free-flow. That could explain the big gain for the Cobra.
Im sure also your A/F ratio is messed up also. Your 02 sensors are not that accurate unless on WOT.
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Re: Dyno'd car after SLP LT install - HELP!!!! </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by cobray:
<strong>Probably your converters are the bottleneck. Stock GM converters are somewhat restrictive (from what ive learned).
I used to have a DOHC Cobra and I know the converters on those are pretty free-flow.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Uhh, both cars had aftermarket headers/cats. <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />
Is it true you should disconect the battery after you install your headers?
<strong>Probably your converters are the bottleneck. Stock GM converters are somewhat restrictive (from what ive learned).
I used to have a DOHC Cobra and I know the converters on those are pretty free-flow.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Uhh, both cars had aftermarket headers/cats. <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />
Is it true you should disconect the battery after you install your headers?
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From: Owensboro KY
Re: Dyno'd car after SLP LT install - HELP!!!! </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by bigSS:
<strong>Is it true you should disconect the battery after you install your headers?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Ummm, did you not disconnect your battery when you were installing them?
<strong>Is it true you should disconect the battery after you install your headers?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Ummm, did you not disconnect your battery when you were installing them?
On The Tree
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From: Tempe, AZ
Re: Dyno'd car after SLP LT install - HELP!!!! Im not sure what the temp is there, but here in AZ MAF ends cause everything to mess up... try dynoing without them and ATAP accordingly, The settings I use out here on my MAFT are +10% Base and -8% WOT winter, and -4% WOT for summer. I also have SLP LTs and SLP cat back.
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From: Schiller Park, ILL Member: #317
Re: Dyno'd car after SLP LT install - HELP!!!! </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by sweetTA:
<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 bigSS:
<strong>Is it true you should disconect the battery after you install your headers?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Ummm, did you not disconnect your battery when you were installing them?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I did not disconnect the battery while I was installing my headers. I like to live on the edge <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
The car will relearn in time. No need to disconnect the battery just to relearn unless you want to.
<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 bigSS:
<strong>Is it true you should disconect the battery after you install your headers?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Ummm, did you not disconnect your battery when you were installing them?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I did not disconnect the battery while I was installing my headers. I like to live on the edge <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
The car will relearn in time. No need to disconnect the battery just to relearn unless you want to.
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From: Owensboro KY
Re: Dyno'd car after SLP LT install - HELP!!!! </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by RPM WS6:
<strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I did not disconnect the battery while I was installing my headers. I like to live on the edge <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
The car will relearn in time. No need to disconnect the battery just to relearn unless you want to.</strong>[/QUOTE]
What about the starter? You dropped it and put it back on with the battery connected?
<img border="0" alt="[fight]" title="" src="graemlins/gr_punch.gif" />
<strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I did not disconnect the battery while I was installing my headers. I like to live on the edge <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
The car will relearn in time. No need to disconnect the battery just to relearn unless you want to.</strong>[/QUOTE]
What about the starter? You dropped it and put it back on with the battery connected?
<img border="0" alt="[fight]" title="" src="graemlins/gr_punch.gif" />
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From: Schiller Park, ILL Member: #317
Re: Dyno'd car after SLP LT install - HELP!!!! I did not have to pull the starter for my install. I have mid lengths.
I agree that if the starter has to come off then disconnecting the battery is a must.
I agree that if the starter has to come off then disconnecting the battery is a must.
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From: Macomb, MI
Re: Dyno'd car after SLP LT install - HELP!!!! Those are peak numbers. Was there any noticible increase throughout the graph curve. Maybe you making more power at lower RPM's, and about the same at peak.
Where did you have it Dyno'd, and what kind of Dyno for this run and the previous runs, and what was the outside Temp for both runs.
<small>[ June 27, 2002, 08:23 AM: Message edited by: HOSS99 ]</small>
Where did you have it Dyno'd, and what kind of Dyno for this run and the previous runs, and what was the outside Temp for both runs.
<small>[ June 27, 2002, 08:23 AM: Message edited by: HOSS99 ]</small>
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From: North America
Re: Dyno'd car after SLP LT install - HELP!!!! Just for a point of fact, I did not have to remove my starter for my FLP install either. But I did disconnect the battery because I was doing a lot of work to the car at the time.