Newly Built LS2 Engine runnig rough
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Teching In
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Newly Built LS2 Engine runnig rough It's been a while since I've posted last but I need a little help with my 79 LS2 conversion Camaro. Engine was rebuilt with all new bearing, gaskets, rings, seals and lifters. Converted to cable TB (92mm Billet Throttle Bodies SUM-227100B) and PCM is of the 411
variety from PSI (not tuned yet). Medium length 1 3/4" headers, Comp Cams XFI RPM High-Lift Camshafts 54-424-11 (dur 212 int./218 exh. lift 0.558 int./0.563 exh.). New MAF sensor from PSI, new in tank fuel pump (Holley OEM Style EFI Fuel Tank Modules 12-304). I started
the engine first time about 6 weeks ago. Injectors are not new and were sticky on first start but engine is firing on all 8 cylinders now. Vacuum is steady @ 15 in Hg. Headers are open (exhaust not complete and O2 sensors are not plugged in. Engine will idle, but response is poor right off idle. However sounds really good and strong above 2500 RPM or so. Just seems rich and sluggish below 2500. Will this improve with complete exhaust and O2s functional?
variety from PSI (not tuned yet). Medium length 1 3/4" headers, Comp Cams XFI RPM High-Lift Camshafts 54-424-11 (dur 212 int./218 exh. lift 0.558 int./0.563 exh.). New MAF sensor from PSI, new in tank fuel pump (Holley OEM Style EFI Fuel Tank Modules 12-304). I started
the engine first time about 6 weeks ago. Injectors are not new and were sticky on first start but engine is firing on all 8 cylinders now. Vacuum is steady @ 15 in Hg. Headers are open (exhaust not complete and O2 sensors are not plugged in. Engine will idle, but response is poor right off idle. However sounds really good and strong above 2500 RPM or so. Just seems rich and sluggish below 2500. Will this improve with complete exhaust and O2s functional?
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From: Bostwick, GA.
"Engine will idle, but response is poor right off idle. However sounds really good and strong above 2500 RPM or so. Just seems rich and sluggish below 2500. Will this improve with complete exhaust and O2s functional"?
Maybe finish the install before you worry about how it runs?
Not sure what you expect with the O2's being inop.
Maybe finish the install before you worry about how it runs?
Not sure what you expect with the O2's being inop.
"Engine will idle, but response is poor right off idle. However sounds really good and strong above 2500 RPM or so. Just seems rich and sluggish below 2500. Will this improve with complete exhaust and O2s functional"?
Maybe finish the install before you worry about how it runs?
Not sure what you expect with the O2's being inop.
Maybe finish the install before you worry about how it runs?
Not sure what you expect with the O2's being inop.
79Camaro…finish the exhaust and any other loose end. I don’t ever recommend anyone trying to start a build without exhaust in place. It confuses the o2’s and you can’t hear any mechanical issues that might arise over the loud exhaust. Then, get it tuned by an experienced tuner who knows the LS platform well.
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Teching In
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Completing exhaust and getting a tune are in the plan. I was hoping to hear from someone who has done a similar build and experienced this issue. I'm sure I'm not the only person who has ever started a newly built engine with an incomplete exhaust system.
On The Tree
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And as far as the tune goes you put a cam in it and it runs at 15 in hg that puts the fueling in a different area of the VE map. Among many other things.
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Teching In
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Why do you need to hear from someone who has done a similar build and had this issue? Sensors are there for a reason, why would it run properly with them not there?
And as far as the tune goes you put a cam in it and it runs at 15 in hg that puts the fueling in a different area of the VE map. Among many other things.
And as far as the tune goes you put a cam in it and it runs at 15 in hg that puts the fueling in a different area of the VE map. Among many other things.
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I most certainly wasn’t looking down my nose at you in post 3, and I apologize to you if you felt that way. I don’t see you having any issues here, other than what’s been mentioned about the o2’s needing exhaust. As long as youve got good oil pressure (the Achilles heel of the LS platform is the oiling system) then you should be able to make this car sing with a good tune. You have made good choices on parts here including cam choice. Keep us posted here after exhaust and tune. Have any pictures? I’m interested!
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Verdad Gallardo Thread Starter
Teching In
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I most certainly wasn’t looking down my nose at you in post 3, and I apologize to you if you felt that way. I don’t see you having any issues here, other than what’s been mentioned about the o2’s needing exhaust. As long as youve got good oil pressure (the Achilles heel of the LS platform is the oiling system) then you should be able to make this car sing with a good tune. You have made good choices on parts here including cam choice. Keep us posted here after exhaust and tune. Have any pictures? I’m interested!
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Teching In
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I'm a little farther along than this right now but these are the most recent. Upgrades include: Tremec T-56 with 2.97 1st gear and .5:1 6th, Eaton Detroit TruTrac w/Richmond 3:42 gears, 180 Lb leaf springs, Eibach shocks all 4 corners, Added rear sway bar rear, huge one up front, Poly body bushings, 4 wheel 12" disks brakes w/Wilwood calipers, 9""dual diaphram, new tubular upper and lower control arms to achieve 5 plus degrees caster. Car will also get cruise control, Raingear wiper upgrade, Dakota Digital gage set and a decent sound system. More pics to come!
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Teching In
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One question, does this site have rules for the size of pix being uploaded. I thought that I would be given the option to re-size them when uploading but that didn't happen. So if you guys don't care either way, I won't either. Let me know please. And thanks!