no gain with slp lt and race pipe
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Teching In
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From: sc
no gain with slp lt and race pipe i dynoed in atlanta w/ air lid, loudmouth and pulled 311 rwhp corrected. i installed slp lt, race pipe w/sims, and egr mod and pulled at a different dyno 317 rwhp corrected. thats a whopping 6 hp increase!! thats actually 7 hp at the crank! that adds up to $183 a horse!! WTF!! i understand that i was not going to get the advertised hp and i know its a different dyno....but 6 hp!!! my A/F was dead steady at a hair under 14. anybody else have any idea of wtf happened or i need to do? is this common? thanks layter <img border="0" alt="[cry]" title="" src="graemlins/gr_cry.gif" />
12 Second Club
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From: Pa
Re: no gain with slp lt and race pipe Never dynod my car but i just put slp long tubes with high flo cats and i notice a huge difference with them. Alot more than 6 or seven horses <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />
Re: no gain with slp lt and race pipe Sorry to hear that. Thats why i went with the FLP's <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> . I gained 23rwhp and 27rwtq with the headers and Off road pipes <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> . By the way my A/F was between 13 and 14 too.
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From: Lakeland, FL
Re: no gain with slp lt and race pipe You do seem to be a little on the lean side and I would also check for knock, I know alot of people bash slp lt's but you really should have seen more of a gain than that, I would think you could see 6-7 hp just from removing the cats alone much less adding a header, FWIW I also have SLP LT's with ORP and I did not dyno right after I put the headers on but I did feel a big difference with them, Once I put my cam in I dynoed 372 to the wheels with no tuning and through a full exhaust and to only 6200 rpm, I had all the mods in the sig at the time of the dyno except for the FTRA and the cutout so I know that it wasn't my cam and lid alone that got me 372. My A/F was around 13.7 to 1 at 2600 and sloped down to around 12.8 to 1 by the time I was at 6200 which is where the dyno operator stopped the dyno. I would say hook it up to atap to see if you have any knock retard and also maybe get a maft.
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Thread Starter
Teching In
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From: sc
Re: no gain with slp lt and race pipe i did have efi live on it an had absolutely no knock, i briefly flashed a .34 but stayed around 23 degrees advance. and if perfect stoich is 14.78, and im running 13.98 or 14, theni would be richer than stoich. does the ls1 need to against the physics and be fatter than stoich to make power? thanks for all your replys, please keep them coming to help me with my hp quest!! layter
oh yeah when i installed the headers i crammed a block of wood between the y-pipe and car to get that bang from showing up, it worked great
<small>[ April 14, 2003, 10:36 AM: Message edited by: spoonss ]</small>
oh yeah when i installed the headers i crammed a block of wood between the y-pipe and car to get that bang from showing up, it worked great
<small>[ April 14, 2003, 10:36 AM: Message edited by: spoonss ]</small>
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TECH Resident
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Re: no gain with slp lt and race pipe </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by spoonss:
<strong> and if perfect stoich is 14.78, and im running 13.98 or 14, theni would be richer than stoich. does the ls1 need to against the physics and be fatter than stoich to make power? </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The "perfect stoich ratio" does NOT produce the most power. It has been proven time and time again on dynoes.
The basic concensus is a/f should be:
12.5-12.8 near peak torque
13.1 at peak hp
Try tweaking the a/f, you should definitely gain power...
Tommy <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
<strong> and if perfect stoich is 14.78, and im running 13.98 or 14, theni would be richer than stoich. does the ls1 need to against the physics and be fatter than stoich to make power? </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">The "perfect stoich ratio" does NOT produce the most power. It has been proven time and time again on dynoes.
The basic concensus is a/f should be:
12.5-12.8 near peak torque
13.1 at peak hp
Try tweaking the a/f, you should definitely gain power...
Tommy <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Thread Starter
Teching In
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From: sc
Re: no gain with slp lt and race pipe </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">The "perfect stoich ratio" does NOT produce the most power. It has been proven time and time again on dynoes.
The basic concensus is a/f should be:
12.5-12.8 near peak torque
13.1 at peak hp </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">thank tommy, i guess i need to get a maft now. do you know anything about efilive pro? if so could i temporary change that ratio on the dyno? thanks
The basic concensus is a/f should be:
12.5-12.8 near peak torque
13.1 at peak hp </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">thank tommy, i guess i need to get a maft now. do you know anything about efilive pro? if so could i temporary change that ratio on the dyno? thanks
Re: no gain with slp lt and race pipe 396RWHP 394RWTQ through full exaust with stage 2 5.7L Ls1 heads that are NOT milled.
I don't like my SLP LT's but they do make power however I have witnessed evidence of Grotts making more than SLP's
I am going to be changing to Grotts before I go with procharger <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
I don't like my SLP LT's but they do make power however I have witnessed evidence of Grotts making more than SLP's
I am going to be changing to Grotts before I go with procharger <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Re: no gain with slp lt and race pipe Well I recently Dynoed my '02 SS at 335rwhp/347rwtq with : SLP LTs, SLP LM, whisper Lid ... Im not sure what a stock '02 SS will dyno at (~305hp) but I did notice a huge diff ... my AFR was around 12.9-13.1
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From: TEXAS
Re: no gain with slp lt and race pipe Well, on my 98, dynoing before and after SLP LT and no cats, I picked up 25hp and 23ft-lbs. Nothing else was changed but the headers and the y-pipe that came with the headers, no tuning. All my other mods up to that point consisted of lid, ported MAF, and dynomouth exaust. Before 312hp/331tq after 337hp/354tq.
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Re: no gain with slp lt and race pipe I do not have EFILive...
I adjusted my a/f by looking at my wideband O2 results when I was on a dyno: http://www.tatommy.com/dynoruns.htm
And made the necessary adjustments with LS1Edit through the PEvsRPM table...
Tommy <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
I adjusted my a/f by looking at my wideband O2 results when I was on a dyno: http://www.tatommy.com/dynoruns.htm
And made the necessary adjustments with LS1Edit through the PEvsRPM table...
Tommy <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Thread Starter
Teching In
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From: sc
Re: no gain with slp lt and race pipe thnx you guys, i guess if i fatten it up i may get at least the 20hp i expected thanks again, also if anyone knows anything about the efilive pro and changing the a/f with it for my next dyno time that would be great layter
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From: katy, tx
Re: no gain with slp lt and race pipe I went from 315 to 330rwhp after installing the SLP headers, Random tech high flow cats and SLP 3" y-pipe. I was a bit dissapointed, but I hear that is respectable for what mods I had at the time which included a Whisper lid, ported MAF, and K&N filter.
Out of curiosity, were both the dynos the same type? There are dynojet dynos and mustang dynos. I just read an article in CHP that did a study comparing and said the dynojet tends to put less load on the car and therefore dynos more. In conclusion they said to stick to the same type and even same location if you can when comparing for mods. Worth checking into. If they are in fact different, go back to whom ever did your first dyno.
Dean <img border="0" alt="[USA]" title="" src="graemlins/patriot.gif" />
Out of curiosity, were both the dynos the same type? There are dynojet dynos and mustang dynos. I just read an article in CHP that did a study comparing and said the dynojet tends to put less load on the car and therefore dynos more. In conclusion they said to stick to the same type and even same location if you can when comparing for mods. Worth checking into. If they are in fact different, go back to whom ever did your first dyno.
Dean <img border="0" alt="[USA]" title="" src="graemlins/patriot.gif" />