Vortech confuzzled.
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Vortech confuzzled. 
Hey, new to the site. I bought a v-9 sq intercooled kit for my stock Ls1 Trans am last winter, full kit with fuel pump and 38lb injectors for 3600 new, any way my question is the motor seems to come alive about 2600 rpm and sighn off about 5000 rpm. I have the programming done by pcm for less mail order tune. Is it bad or weak valve springs? program? what kind of power can I get out of this set up? I would honestly not rely on a mail order tune on a forced induction car. Every car is slightly different. Also, if the valve springs are stock, it would be a good idea to upgrade them as well.
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i would like to go get a dyno tune but living in the middle of Iowa I don't have to many options unless I drive to Speed Inc. in Chicago. I was kind of dissapointed with this set up. I figured it would pull harder,even with my 4-10 gearsand my 305-35 18 nitto's. I may need to look into a good set of heads and a cam to reach that goal of 525-550hp. Trending Topics
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I got this kit off e-bay for 3600, it was all brand new in a box, everything worked except the inline boost a pump, I ordered a new one from vortech. The blower is making right around 9-10psi. I Have a autometer guage plumed into the elbow right before the throttlebody.I may be wrong but I thought I would be able to have a night and day difference in power. I mean I can tell it has more hp at higher speeds but it seems like the power spread is short,I don't know if it is tune, not enough fuel or injector. How much difference is a tune going to make over my mail order PCM for less tune? Valves floating out at about 5300 Rpm due to the new boost? 
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Teching In
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From: anaheim, ca
My 2000 camaro with vortech v-9 and intercooler is at the dyno shop orange county dyno in brea ca. Its low on boost 4-5 (I dont know why) and it is putting 380hp to the wheels and 400lb of tq on a dyno jet dyno. We replaced the standard bypass valve with a new one. My car has Lt headers cats and full exhaust with a flowmaster a mild cam so it will pass smog full egr setup and stock throttlebody and mass air. Block heads and everything else is stock. I dont know how to figure out the boost issue on mine but it sounds like your boost is great. Btw tuning for Lt is a nightmare if I would of known what I know now I would of stayed with shorties or or stock exhaust manifolds from a corvette or something similar. My blower pulley is 3.125 I think I was going to swap to a 2.75 what pulley do you have on yours? I would love to have 9-1.0 My injectors are 42lb sounds like yours are a little small.
Last edited by motohead77; Dec 24, 2010 at 01:28 PM. Reason: forgot some info
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I have long tube headers (pacesetter) with offroad Y-pipe. I have the stock pully on it not sure what size off the top of my head? I thought about putting a smaller pully on it for more boost-power but not sure how much it can handle before it pops like a tick.
how many miles are on the springs in the car, are they stock, have they been over heated, how many lbs of pressure they have on the seat, were they set up at the right height?
so you've brought it up twice, i think your on the right track. did you put springs on it with the blower install, have you checked seat pressure?
this would be the first place i would look from what your saying the motor does, what springs do you have?
i will say if their stock with XXX,XXX miles with 9-10 lbs of boost they won't hold the valves shut, and every time you float them the harmonics kill them even more, and doesn't do the lifters any good either.
i had a prochargered guy call me with the same problems you are having, he was running the stock high mileage springs. motor would come on strong for about 2000 rpms and fall off, i told him to check the springs seat pressure and they were weak. put new ones on and the motor pulled to red line like a champ.
internet/phone diagnostics is a guessing game so i'm not saying i'm 100% right, but from what you are saying that's where i'd start. no matter what it is, you need to rule them out before moving on. if your springs ARE weak and it's been in valve float a few times i'd replace the lifters too, roller lifters don't like float and their cheap compared to what they do to a motor when they come apart.
Last edited by nxfirebird; Dec 24, 2010 at 11:42 PM.
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The car has about 60,000 miles on it. Thank you for your advice, I was thinking instead of just replacing springs I would buy a set of new budget ls6 heads and a cam and do both to try and remedy the problem. Hopefully.
yeah at 9-10 psi regardless of wether or not your floating them they still need to be replaced, they just werent made for that. plus, with a stock long block at 10 psi you should be making right at or just over 600 to teh wheels 4l60e or t56 so yes something is most definately wrong.
heads and cam will REQUIRE new injectors, would suggest 60lb or better. No matter what though, consult an expert before you order the valve springs though, its not an area you generally get a second chance at.
heads and cam will REQUIRE new injectors, would suggest 60lb or better. No matter what though, consult an expert before you order the valve springs though, its not an area you generally get a second chance at.
If you are in Iowa just take it to speed inc like you mentioned. They will get you fixed up and when they get it on the dyno figure out what is wrong. If your fuel pressure is dropping at wot you may need a bigger pump. I had a v9 on my car first and I had a walbro 340 fuel pump, and 60# injectors. With the 2.95 pulley mine made 500@the wheels.
