Stock lq4 boost ??
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Teching In
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Stock lq4 boost ?? I have a 2004 lq4 going into a 98 trans am and was wondering will it live at around 15 psi from a 76mm turbo or do I need to regap the stock rings? Any tip or advice appreciated .
Last edited by andry3000; Jan 25, 2014 at 10:40 AM. Reason: Typo
I'm at 13.5-14psi on a stock bottom end LS3. I think as long as the motor has some miles on it you will be fine. On the flip side, if you have the knowledge and tools to do it yourself, it can't hurt to open the ring gap a little. At that point I would be tempted to run a ball hone through it and install new rings though.
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From: Arkansas
I ran one in my fairmont for a year on 15 to 20 psi . The motor was completely bone stock no valve springs , stock cam, stock intake . All I did was change the plugs and change the oil. I wouldn't have blown a head gasket if a flew bellow wouldn't have collapse on me. It ran 7.23 in the 1/8th mile on 14 inch cooper cobra's with a 273 gear.
On The Tree
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From: Greensboro NC
I ran one in my fairmont for a year on 15 to 20 psi . The motor was completely bone stock no valve springs , stock cam, stock intake . All I did was change the plugs and change the oil. I wouldn't have blown a head gasket if a flew bellow wouldn't have collapse on me. It ran 7.23 in the 1/8th mile on 14 inch cooper cobra's with a 273 gear.
What was your MPH?
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Verdad Gallardo It would definitely do the LS9 head gaskets. Not sure if the LS6 or LS9 cam would be a better choice. My buddy has a GTO with a 4.8 and PT7675 with an LS9 cam and that suckers dyno curve looks like a Supra, lol. Stalled auto with a 50hp shot of nitrous, so it works damn good in Mexico.
I would open the top rings up to .028-.030. Don't usually touch the 2nd ring. If you are going head gaskets and head studs, you just as well to the rings and rod bolts.... onle few extra hours of work.
On The Tree
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I have an 02 lq4 with 115k, at 15 psi on pump/meth keep the AFR and timming low, Im at 10.9 and 12 degrees. If you have a low mileage engine you might want to open the ring gap but Id do studs and gaskets while the engines out. I did rod bolts, wished I wouldn't of sucks to pull apart a 110K engine with every thing looking as good as new and wonder if the new torque on the rod bolts changed anything.
9 Second Truck Club
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From: Colorado Springs, Co/ Central, Ca
Both car and truck in sig are stock bottom end 6.0's with ported factory heads, my Custom cams, single pac/Isky springs, ls9 head gaskets, and ARP studs. For me the stock head gaskets, with tty bolts start to fail around 16psi. Stock gaskets with arp studs hold to about 20 psi. If it were me I would spend a tad more on a decent cam. The out of boost response and tq under the curve is worth the extra cost.
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From: Statesville, NC
My ls1 stock bolts and gaskets pushes water after 6000rpm also at 16psi. Or that's the level it started doing this anyway. 12-13 degrees timing up top. Pump 93/meth. I push it to 21psi on the street. Pulls like a train lol. Just keep my rpms down for street fun. My 28" slicks and 3.42s make 4th top out at 160+ so not hitting that much lol. Just let it eat a few seconds and feel the rush and I'm good. That's probably why stock drive train lives at nearly 900rwhp.
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Teching In
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The car will be running 93 it's a street car . It's an 2004 lq4 with 110k miles on it. I don't think ill do arp rod bolts but I'll do the head studs and ls9 gaskets it going in a 1998 trans am any opinions on turbo size?
Both car and truck in sig are stock bottom end 6.0's with ported factory heads, my Custom cams, single pac/Isky springs, ls9 head gaskets, and ARP studs. For me the stock head gaskets, with tty bolts start to fail around 16psi. Stock gaskets with arp studs hold to about 20 psi. If it were me I would spend a tad more on a decent cam. The out of boost response and tq under the curve is worth the extra cost.
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The right cam will pick up response and tq thruought the whole curve pretty much from idle up. What I don't like about the wide cams like the ls9 and ls6 is they lose a lot down low right where you opperate on the street, and start to spool the turbo.
Turbo size depending what you want to do with the car. But personally i would go with a custom spec'd cam and a S480 its cheap and you will make as much power as you will need for a street car if you dont want to spend the money look for a used TU2 cam that made plenty of power on my old set up.