Lq9 or lq4 over the ls1 debate for boost
#1
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.
#2
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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).
#4
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
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#9
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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)
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#13
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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
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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.
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
#17
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
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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
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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