DrEvil3264 Posted February 9, 2005 Report Share Posted February 9, 2005 hey im posting this for a friend, the other night he raced and when he hit 5000 rpms approaching redline at 5500 the car felt like it lost power, is this a known flat spot on the LT1's, or is there possibly something wrong? Thanks for ne replys... Quote Link to comment Share on other sites More sharing options...
hpfiend Posted February 9, 2005 Report Share Posted February 9, 2005 Hello Ninja, No, that is not normal- my 96 Formula LT1 would pull all the way to 6000 with out any flatspots/hesitations... I had bumped the revlimiter up tho... Has he added roller rockers/different timing chain? somtimes the noise these items make can create "false knock" and the computer will pull timing. Tell him to check his plugs for gap, a complete PITA on the LT1, fuel filter, make sure he is also using good gas (shell, sunoco)... If the miss is strong it may be a plug wire or bad optispark but usually this is noticeable at below 3500 rpms and you hear the plug wire in the radio- I did... Anyways... hth Quote Link to comment Share on other sites More sharing options...
DrEvil3264 Posted February 9, 2005 Author Report Share Posted February 9, 2005 thanks man, i told him what u said, i think hes just gonna take it in for a tune up and get it looked over, thanks for the help, o and by the way he has nothing done to the car besides a K&N air filter Quote Link to comment Share on other sites More sharing options...
Clifford Automotive Posted February 10, 2005 Report Share Posted February 10, 2005 if he's pushing the 100,000 mark i'd be looking into the optispark unit Quote Link to comment Share on other sites More sharing options...
smokin5s Posted February 10, 2005 Report Share Posted February 10, 2005 mine pulls strong all the way to 7k... even when it was stock, it pulled until the 5500 shift point.. honestly, it could be a million things... you just gotta get in there and start looking at things... could be something as stupid as a vaccum line (ask Anthony about that) or it could be some crazy valve train noise. Is this car completely stock or does it have mods? I'm gonna go with the opti on this though.... Opti's aren't always visible at low RPM's... on the car I just replaced an Opti in, it would run fine until high RPM's then it would almost feel like it was missing (this of course was after he said that it felt like it was missing top end power before this) then finally it completely died on the side of the freeway one day.... like was stated above... if he's over 100k miles and on his stock Opti, it might be a good idea to replace it anyways.... I have the hookup on GM parts and I can get him in contact with someone who will give him about 100 off of what a dealer charges for a new OEM Opti. Quote Link to comment Share on other sites More sharing options...
hpfiend Posted February 10, 2005 Report Share Posted February 10, 2005 Opti is a PITA to install tho- I totaled mine before I had to do it- the wires were enough for me! That ended up fixing the problem - no7 or no8 was split at the boot- radio noise and occasional serious miss around 3K. THat is true the opti can show up at different rpms but a lot of times it is below 3500... ask this same message on www.camaroz28.com or join the f-body mailing list... I was a member from 1995 until this year.. I got my opti from www.gmpartsdirect.com cheap as I thought that was what was wrong- slow shipping but good prices- sounds like a deal that you have there tho shitaro on the gmparts- tell your friend to enjoy- I miss the LT1/T56 combo- beautiful- hard to work on but nice- Quote Link to comment Share on other sites More sharing options...
Clifford Automotive Posted February 10, 2005 Report Share Posted February 10, 2005 IF IT TURNS OUT TO BE AN OPTI, DONT BELIEVE EVERYTHING YOU HEAR. THERE NOT HARD TO PUT IN. JUST SOME BULLSHIT YOU HAVE TO DEAL WITH. Quote Link to comment Share on other sites More sharing options...
BIG SHAFE Posted February 10, 2005 Report Share Posted February 10, 2005 This is a very common problem for F-Bodies, check this out . I'm not convinced it is the opti though, like most people mine will miss around 5200 RPM and then pull on through, but it gets worse in the higher gears. In first gear I don't notice it, but in third and fourth I can. I'm wondering if there is some harmonic/noise event going on that the knock sensor picks up at that RPM? My car does it and it is totally stock, so you aren't the only one. [ 10. February 2005, 02:22 PM: Message edited by: BIG SHAFE ] Quote Link to comment Share on other sites More sharing options...
DrEvil3264 Posted February 10, 2005 Author Report Share Posted February 10, 2005 thanks a lot of all the help guys, ill ask him and see what hes gonna do, if hes gonna get a new opti im sure he'll take ur offer on getting the $100 off, thanks guys Quote Link to comment Share on other sites More sharing options...
smokin5s Posted February 11, 2005 Report Share Posted February 11, 2005 Opti's aren't very hard to install... ignore anyone who says otherwise... damn ford guys trying to make things harder than they need to be tongue.gifsmile.gif man I've done enough of them that as long as you have a garage to work in, I'll help you out... GMPARTSDIRECT is a rip off... they KILL you in shipping. Quote Link to comment Share on other sites More sharing options...
Guest xxxyyyzzz Posted February 15, 2005 Report Share Posted February 15, 2005 Back when I had my '94 Z28 an LT4 knock sensor fixed the problem. Mine was intermittent though, but I could tell it was a timing issue because it was down on power at that range just like when I put some allegedly 91 octane Stop-N-Go gas in it. The info from the thread Big Shafe linked was good stuff as well, plugs, wires, opti, fuel filter, pump, etc. Quote Link to comment Share on other sites More sharing options...
Rotarded1647545491 Posted February 15, 2005 Report Share Posted February 15, 2005 Do not get coolant in the opti or you will kill it. Quote Link to comment Share on other sites More sharing options...
smokin5s Posted February 16, 2005 Report Share Posted February 16, 2005 Originally posted by Rotarded: Do not get coolant in the opti or you will kill it.werd! the car that I replaced the opti in 6 months ago had the radiator go out and the people that replaced his radiator got coolant EVERYWHERE because they didn't seem to realize there is a relief valve on the top of the water pump and it looks like the opti is going out again... so heed what Mike says... Coolant > Opti everytime! Quote Link to comment Share on other sites More sharing options...
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