LSX based motors

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jfg455

The Hot Rod Cop
Joined
Apr 8, 2010
Messages
3,828
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So I'll start a thread here for LSX based motors with power adders EG: turbos and blowers. I am horribly slow at updating stuff but I will try to stick with it. I am by no means an expert on the subject and there are a ton of guys building more power, going faster etc but I will share what I know.

5.3L T72 turbo set up:

This is about as basic as it gets. A bone yard LM7 5.3L engine is 9.4:1 compression and has heads comparable to the older F and Y bodies. Some even had 243 heads on them. It does share the same stroke crank as the 5.7 and 6.0L engines of the same family but with a smaller bore. I will post specs later on in the thread. Take this motor stock, swap to an 04 Z06 cam and springs, upgrade to 60 lb injectors and add ARP rod bolts. This is the extent of your internal mods. Use the truck maniflods pointing forward, build a Y pipe to a T4 turbo flange and add a Master Power T72 .86A/R turbo. These run right around $650 and are not the cheap Chinese junk. You are going to want to go to 2 wlabro 340 fuel pumps or an Aeromotive A1000 pump. Use a 1:1 boost referenced fuel pressure regulator as well. Add an ebay 24x12x3 air to air intercooler. Next part is a Methenol injection set up. I like to run a progressive style with it's own map sensor. It comes on at 8 psi and ramps up the pump speed as the boost goes up. You will need a 2 bar MAP sensor as well. Run a 50mm-60 mm waste gate. Too big will hurt you way less than too small. Keep boost to about 18 psi and keep overall timing under 18 degrees under full boost. The 0411 truck PCM is easily tuned for boost and the nice part is you can use the GM knock sensors. They spent millions calibrating them so why not use them. You can set the PCM to ignore a couple of counts of knock (2-3) but any more and you will run the risk of pushing a ring land off a piston (ask me how I know!) This set up on 94 octane pump gas and 100% meth (don't run a water mix) will net you around 600-630 crank HP all for under $4500 if you do all your own work. Don't let it knock and it will live a long time.
 
Here is one I am currently working on for my chevelle:

6.0L LQ9 iron short block with L92 heads (square port truck heads. Same as LS3 but without lighter valves), LSA 1.9 blower and an LS9 cam shaft. This should be good for 550 - 575hp range.

The LQ9 vs LQ4 differences are in the pistons, cam profile and PCM tune. The biggest difference is the LQ4 has dished pistons and the LQ9 has flat tops. 9.1:1 compression on the LQ4 vs the 10.1:1 for the LQ9. Both of these normally motor come with 317 cathedral port heads (casting number on the corner) which flow pretty good and have 71cc chambers. Another side note is you can drop the 317 heads onto a 5.3L which gives you bigger valves but also drops your compression ratio down to around 8.4:1. This is boost friendly if you like to run big psi numbers. Only draw back is if you have a heavy car it will sacrifice low end torque.

LSA vs LS9 blowers. Biggest difference here is the LSA is a 1.9ci blower vs the LS9's 2.3 ci. There are different lids for the LSA blowers too. The CTS-V lid is the lowest and it will cause some internal turbulence if you are over driving the blower. The camaro ZL1 lid is taller and doesn't cause as much turbulent air in higher boost situations.

Another area to look at is the spacing of the accessories. Corvette has the tightest to the front of the block but they are wide across the engine. F Body (camaro) is slightly farther out and also wide. Both are low and work well for hood clearance.
Truck accessories are 3/4" farther out from the motor and are narrower. They are taller and work well with tall narrow engine bays.

The LSA blowers are driven by a separate 8 rib belt. The 8 rib section of the LSA crank pulley is the same distance out from the front of the block as the truck accessory drives 6 rib pulley. If you are creative with bracketry you can run the LSA blower from the truck 6 rib belt though you may get some belt slip at higher rpm. You can swap out the pulleys on the alternator, p/s pump and idlers to Ford 6.0 / 7.3 diesel units and run everything with an 8 rib belt using the LSA crank pulley.

Look here for a ton of front drive mounts and ideas for A/C compressors etc

www.lssimple.net
 
some ideas...
Z06 LS7 ATI blower

5.3L T72 turbo

6.0L LQ4 T76 turbo

LS2 destroked to 330 ci custom accessory drive
 
Mods - is it ok to post links to other websites for informational purposes? If not then just remove. Thanks.

Oil pans - http://ls1tech.com/forums/conversions-hybrids/817787-lsx-oil-pans.html

Swap guides by specific bodies (1 generic version too) - http://ls1tech.com/forums/conversions-hybrids/1446712-lsx-engine-swap-guides.html

Engine designations


Significant Gen III Engineering Points:

1. All Gen III truck engines use iron blocks. Only the Camaro (F-Car) and Corvette (Y-car)LS1/LS6 engines feature aluminum blocks.

2. All Gen III engines have aluminum heads except for the '99 LQ4 engines that were equipped with iron heads. These engines received aluminum heads for the 2000 model year.

3. All Gen III engines share common main,rod,and cam-bearing journal diameters for ease of interchange. All blocks use a cross-bolted six-bolt main cap.

4. All Gen III engines are completely metric.

5. All valvetrain pieces are completely interchangable. The standard rocker ratio for all Gen III engines is 1.7:1.

6.All Gen III truck engines use cast aluminum oil pans that are deeper than the camaro or corvette pans.

7. All intake manifolds interchange. The truck intakes are roughly 3-4 inches taller than the passenger-car intakes.

8. All Gen III engines employ reusable gaskets for sealing surfaces except for the head gaskets. This makes it much quicker and easier to service the engine.

9. There are only two intake valve sizes for all the Gen III engines. Exhaust valves are all the same diameter.

10. Truck and camaro engines use cable throttle linkage while the corvettes use an electronic throttle. There are also some SUV engines with traction control that use electronic throttle control.

11. Bellhousing patterns are the same for all Gen III engines. The crank flange is basically the same depth as the bellhousing flange.

12. The Gen III firing order has been revised from 1-8-4-3-6-5-7-2 to 1-8-7-2-6-5-4-3. Note that the pairings 1-8, 4-3, 6-5, 7-2 remain the same, but the pairing order is different for reduced vibration.

13. The valve angle on all Gen III engines is 15 degrees versus 23 degrees for the origional and Gen II small-blocks.

14. The Gen III bore spacing is the same as the origional small-block, but each cylinder is ringed with only four head bolts instead of five.
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Custom Cubes:
If you are fortunate enough to get your hands on an LQ4 6.0L engine block, you can bore it .030-over and purchase a 4.250 Lunati stroker crankshaft to produce a 434ci. GenIII engine.

Add a set of GM Performance Parts ZO6 cyclinder heads (PN 12560801) or have the stock LS1 heads ported and you've got yourself a serious engine.
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Here is the start of a 2010 L96 (6.0L truck motor) that is getting the LSA supercharger setup from a CTS-V. These are square port heads. It is also getting the LS9 corvette cam and springs along with long tube headers. I deleted the VVT (Variable Valve Timing) too. I will show the bracket set up that drives the blower with the accessory belt as well.

 
DMW - With that combo, even with the smaller 1.9 blower, you should be in the 575-585hp range. LSA CTS-V runs 550 and you have a better cam, better lid and long tubes with a tune...[cl
 
DMW - ah I see now you were looking for 550 Wheel hp...

I'm headed to the dyno with the 2500HD-V I just put together. I have almost the same combo except it's on a 6.0L L96 long block. The trans, tires and heavy axle will rob some of it's power I'm sure...[cl
 
So the dyno run was a success. Keep in mind this is a 2500HD 4WD truck with 36" tires on 20" rock star rims. Bone stock on this dyno the truck made 241 RWHP (GM rated at 360 hp at the crank) After the cam swap, blower and headers it made 387 RWHP at 7psi of boost and only 14 degrees timing. Do the math on the drive train losses and that puts it right in the 495-500hp mark at the crank. Suddenly makes the 7600lb truck a bit more fun to drive! [cl
 

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