Lq9 or lq4 over the ls1 debate for boost
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Lq9 or lq4 over the ls1 debate for boost right now i have a twin turbo ls1 on 8lbs of boost.... added about 200hp....
not sure the stock 5.7 can take much more than 8lbs...... so i was thinking of building an lq engine....... i know the lq4 has less compression....... if u are leaving the short block stock is the lq4 better since it has lower compression ? other than compression ratio...... is there any advantage to using the lq9 over the lq4 ? cause i can get a complete LQ4 so much cheaper.
and......... how much boost can the stock lq 4 or 9 take ?
thanks for the help.
not sure the stock 5.7 can take much more than 8lbs...... so i was thinking of building an lq engine....... i know the lq4 has less compression....... if u are leaving the short block stock is the lq4 better since it has lower compression ? other than compression ratio...... is there any advantage to using the lq9 over the lq4 ? cause i can get a complete LQ4 so much cheaper.
and......... how much boost can the stock lq 4 or 9 take ?
thanks for the help.
right now i have a twin turbo ls1 on 8lbs of boost.... added about 200hp....
not sure the stock 5.7 can take much more than 8lbs...... so i was thinking of building an lq engine....... i know the lq4 has less compression....... if u are leaving the short block stock is the lq4 better since it has lower compression ? other than compression ratio...... is there any advantage to using the lq9 over the lq4 ? cause i can get a complete LQ4 so much cheaper.
and......... how much boost can the stock lq 4 or 9 take ?
thanks for the help.
not sure the stock 5.7 can take much more than 8lbs...... so i was thinking of building an lq engine....... i know the lq4 has less compression....... if u are leaving the short block stock is the lq4 better since it has lower compression ? other than compression ratio...... is there any advantage to using the lq9 over the lq4 ? cause i can get a complete LQ4 so much cheaper.
and......... how much boost can the stock lq 4 or 9 take ?
thanks for the help.
I plan on echieving 600-650rwhp on 8lbs and 750-800rwhp (with meth) on 14lbs. If I blow it up, just gives me reason to beef it up. We shall see!
To answer your question on block difference's, I believe they are indentical, just different rods (lq9 better rods) and pistons (ie compression).
Thread Starter
On The Tree
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Well..... I can pick up a turnkey 60k LQ4 for 700 or a 40k LQ9 for 1000 but I wanna leave the bottom end alone....isn't th 10.5 compression to much for the aps tt kit at 10 to 12 psi ? All I will do to motor is head work and mild turbo cam
99 and some 2000s had a longer crank flange to make it work with the 4L80 without making changes to the bellhousing. Later ones use a spacer to back the flexplate out toward the torque converter, and use standard GenIII dimensions.
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I bought a complete 80k mile junkyard LQ4 for $800 and plan on testing it's limits witha front mount single 76 turbo (MPT76, Q-Trim, 72AR charge, 1.00AR Exhaust). Other than a new timing chain, blower cam (mild, 224/234, 567/577 115), LS6 oil pump, chromoly pushrods, 918 springs and retainers, it is internally stock with stock manifolds. Other parts I am using is LS6 intake, BBK throttle body, motortron 60lb injectors, racetronix fuel pump kit, cobalt map sensor.
2000+ (The LQ4s with the short crank flange)
Yes
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From: Colorado Springs, Co/ Central, Ca
If the LQ4 is 05 up I would go go with it, but if not go with the LQ9 and run good fuel at high boost. The rods are the week link on the 04 down LQ4's, and will bend and fail well before the piston if the tune is right. LQ9's have the better rods.
9 Second Truck Club
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From: Colorado Springs, Co/ Central, Ca
My 4950LB Z71 4x4 with a stock bottom end 01 LQ4 went 10.65@127MPH 16psi 5000' elv, tried to run 16psi at lower elv went 10.59@124 hurt then snapped two rods on the next run. When I pulled it apart every rod was bent, and pistons were .020''~.100" in the hole. Pistons were still intact, even #7. Here is one of the rods that was untouched by debris
I bought a complete 80k mile junkyard LQ4 for $800 and plan on testing it's limits witha front mount single 76 turbo (MPT76, Q-Trim, 72AR charge, 1.00AR Exhaust). Other than a new timing chain, blower cam (mild, 224/234, 567/577 115), LS6 oil pump, chromoly pushrods, 918 springs and retainers, it is internally stock with stock manifolds. Other parts I am using is LS6 intake, BBK throttle body, motortron 60lb injectors, racetronix fuel pump kit, cobalt map sensor.
I plan on echieving 600-650rwhp on 8lbs and 750-800rwhp (with meth) on 14lbs. If I blow it up, just gives me reason to beef it up. We shall see!
To answer your question on block difference's, I believe they are indentical, just different rods (lq9 better rods) and pistons (ie compression).
I plan on echieving 600-650rwhp on 8lbs and 750-800rwhp (with meth) on 14lbs. If I blow it up, just gives me reason to beef it up. We shall see!
To answer your question on block difference's, I believe they are indentical, just different rods (lq9 better rods) and pistons (ie compression).
Its within a couple of days to completion. Looking forward to 600, nothing more than 650rwhp with that setup. Sounds like we have everything to accomplish that goal
Teching In
Joined: Mar 2005
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If its any help , I have a stock 5.3 180k motor out of the junk yard. I put the motor in my 94 s10, 2 speed glide , s476 turbo 20 psi, 60# injectors , super safe tune , hp tunners 3 bar tune, motor is bone stock except for a 98 ls1 intake. it runs fine and has taken my truck down the track 10.1 @ 136 . I guess my point is these ls motors are strong as hell and i too have a 6.0 ready to go in once the little 5.3 pops. 00 6.0 afr 225mpi turbo cam , apr head studs .. <- i hope the new set up will take me in the low 9's
Originally Posted by trnsfmr99
This sounds like my setup that's under construction too
Its within a couple of days to completion. Looking forward to 600, nothing more than 650rwhp with that setup. Sounds like we have everything to accomplish that goal
Its within a couple of days to completion. Looking forward to 600, nothing more than 650rwhp with that setup. Sounds like we have everything to accomplish that goal
We have a 4400lbs C1500 pick up w/5.3 T70 15psi and meth goes 11.9 @ 121 Totally stock except z06 cam and springs. Use a 2001 up LQ4 as they have alum heads and short crank. The blocks have been over 1700 hp, the crank is good to 900-1000, stock rotating asm will make 750ish with meth or race gas but you really have to watch the tune. Even a 50 degree day or night can be enough to lean it out a little and melt a piston. We cracked a piston with the 5.3 due to low fuel level in the tank on a lauch. Uncoverd the fuel pick up for a second and that was it! JMHO 