Crazy thought or is it?

Rowdy_GMC

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Does the Blown LSX Engine fit inside a Sierra, if it does hit this up with your thought about this.
 
It should fit inside the engine bay of a Sierra, but i would skip on doing that. The LSX is based on the LS7 and was not designed to work with a blower, but N/A for the high compression ratio. You can build the engine up to take a blower, but your going to have to drop the compression to 8.5:1 to keep it street friendly. You may get away for 9.1:1 compression but you may start running in to big problems.

The higher the static compression ratio of the engine the less boost you can run and still use 93-94 octane pump fuel. Usually on a 9.5-1 engine the most boost you can run is about 2 psi before you get above the octane rating of pump gas. That level of boost will usually not make enough additional horsepower increase to offset the cost of the blower. Remember, it takes horsepower to make horsepower with a roots type blower. The car will run slower if you do not make enough horsepower to run the blower!

Blower engines like timing advance. If the initial timing advance is not enough it will cause these issues, over heating and glowing headers. Most blower engines will run between 12-20 degrees of initial timing and a total of 30-32 degrees. You do want a fairly fast timing curve. All the timing should be in by 2500-2800RPM.This is just a guideline. All engines are different. The other main address is a lean running engine. Make sure the fuel systems are tuned correctly for the setup and there are no ECM issues. Remember the blower moves a lot more air through the engine so it needs more fuel as well!

To add a blower to any engine is going to depend on what the setup is and what you are going to do with it. If it is strictly a race setup with no street use then usually you can get away with a standard Roots Blower with the proper fuel system. This does not work well on an application that will get mostly street time. Nothing will kill a blower or Nitrous engine quicker that a lean condition. You want plenty of fuel available for the engine to use .There is a thing you need to know about the power valves on a roots style blower engine. The power valve is installed to keep the engine from loading up and running rich at an idle. On a normally aspirated engine the engine vacuum at idle will hold the power valve closed. When you step on the gas the throttle plates open and the engine vacuum drops as you accelerate. When the vacuum drops below the rating of the power valve , it snaps open and riches up the main system.

Once you get the basic on the blower and fuel, now you going to have to work on the Ignition system and upgrade that too. Your going to have keep an eye on your spark plugs more often, since your going to have to run a good cooper core plug and colder which will carbon up much faster on low boost. To hot of a plug on the higher boost will case them to deteriorate or start to glow and detonation is guaranteed, just like with using the platinum plugs.

If your looking for a street friendly engine, you can go with the larger displacement N/A engine with a higher compression ratio that would give you a neck snapping torque. Or you can go with adding a Turbo charger to your 5.3L or 5.7L vortec engine and running a moderate boost of 9PSI with a Alcohol injector to be safe not to detonate at WOT. A simple set up like that can be done with Dyno Tuning your ECM for the extra Boost and if you keep your boost below 6PSI, i believe the ECM can compensate enough for the extra fuel, but your going to have to get that Checked on a Dyno or with a air/fuel ratio meter.

Your basic ECM, when your gas peddle is used 3/4 only. The ECM reads the signals from your O2 sensors and combined readings with the MAF sensor, will try to keep the air/fuel ratio (A/F) at 14.7:1. Once the peddle is passed the 3/4 mark, the O2 reads are no longer used and the readings from the MAP sensor is taken with the MAF sensor making the engine run richer to around 12.5:1 to ensure your engine does not detonate. These perimeters are programed in your ECM and Dyno tuning the engine will change the perimeters to your engine to what the fuel and timing needs to be. That is why when your flat out on the hammer lane with your truck and you let off on the peddle slowly, you can feel the engine surge a bit more HP. That's when the ECM starts taking readings from the O2 sensors again bringing your engine back to the best optimum HP to a/f ratio.

Hope this helps shine some light to your question, if not bring more questions LOL. Good luck and keep us posted.
 
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Wow, im fairly new with upgrading trucks, i drive a stock Sierra 5.3L Extended Cab. But, im really interested in upgrading it to make it beast. I brought that LSX idea cause i saw it in Truckin Magazine a guy was too big for the New Vettey, and decided to put the LSX Engine in a 00-03 Extended Cab Silverado, he's riding that clean with Vette Power.

All the info sounds really usfuly but, im new like i said.
ill bring some more ideas.

Thanks.

-Daniel
 
As for the potential of the 5.3, I know it well. Over on performancetrucks.net there are plently of 99-07 trucks in the 12's with N/A 5.3s. The 5.3 has a smaller bore, 96mm vs 99mm on the 5.7LS1, you'll need a cam change to really wake up your 5.3. You Can Tune That 5.3L To Outspec An LS1 5.7L. Its Capable! I Promise Ya.

The 5.3 bore is 3mm smaller than the LS1 and does not offer any breathing advantages over the larger bore. With the same stroke as the LS1 the piston speed is the same so you'll need more cam timing for the same cylinder filling. So essentially, to beat an LS1 you'll need more compression, more cam, and more tuning.

he 5.3L Has Higher Flowing Heads Than The LS1 and The 5.3L Is Detuned From factory. Id Put The 5.3L Against The LS1 Anyday, Thats How Much Potential This Engine Has. Not Saying The LS1 Doesnt Either. Its Just That The 5.3 Is An Capable Engine. Not Many People Know This.

Break out the flow bench numbers for the 5.3 head on a 96mm bore and a 99mm bore. You can get into a bench racing match if you'd like but the truth of the dyno is that you can build a 5.3 to whomp a LS1, but anyone who is remotely serious doesn't mess with the 5.3 or the 5.7 (LS1/LS6), they go for the larger bore blocks. The 5.3, 5.7(LS1/LS6) and 6.0 have the same stroke. Smaller bores, with the same stroke, produce much higher port veolicities. Larger bores allow for more efficient cylinder filling, which results in more power. GM isn't stupid, that's why the L92 is so incredible and why the L92 heads on a 6.0 make it brutal.

The L33 Vortec Heads, And The LM7 Heads (Both Higher Flowing Than The LS1 5.7L) Ive Worked On LS1 Powered Camaro's, and Under The Hood (When There In The Shop) we install alot Of 5.3L Heads On Top Of The LS1 5.7L Engines. Yes The Bigger The Bore The More Power, Thats Just A Given, All Im Saying Is That The 5.3L Is Capable Of Producing Pretty Serious Numbers. It All Just Depends On How Much $ Your Wanting To Dump Into It. Just Like Now You Can Go Buy A Brand New Turn Key Naturally Inspirated 650Hp 5.3L, Were Not Talking With The Supercharger And All, Im Talking All Motor. Yes No Doubt The L92 Heads Are Great, And Would Wake The 6L Up Astoundinly, But It Would Also Increase The Power Amazingly On The 5.3L.

The reason so many LS1 cars run 5.3L heads is not becasue they flow better. Stock for stock LM7 heads flow nearly identical to LS1 heads. It's for the smaller combustion chambers to raise compression. The smaller chamber also means that the head can be ported more without needing to mill them down to regain compression. The L33 5.3L runs the same heads as a LS6, but without the lightweight valves which definately flow better than LS1 heads.

Too keep things simple and power you want, just add a turbocharger with no more then 9PSI. I'd keep it around 6-7PSI with a alcohol injector just to make sure the engine does not detonate at WOT, and a good inter cooler and of course having the ECM flashed to accommodate the extra Boost.

As for the transmission, you can beef the 4L60E as Noted in the GMC Jimmy forum with bark or 98jimmykat. Hope this information will keep you in your 5.3L Vortec.
 
that turbocharger sounds good with the 9PSI, but where can i get a turbocharger? and for how much do they go for? ECM is the computer right? cause i floored it on the Sierra the other day and the speedometer jumps at around 90-95.
 
As for your speedometer jumping around, check your Vehicle Velocity Sensor (VVS). Inspect your wire harness leads which is located on the drivers side by the transmission tail shaft, if the wire leads and connection are good. Your VVS may be on it's way out and will need to be replaced.

The other thing to is there is a TBS GM has had a issue with the clusters in the 2003-2005 trucks. The cluster will be replaced for free for your truck if it has less then 70k miles. I would take it to your local dealer and tell them that the speedometer gauge sticks at times. They should order one for you, takes 1-2 days and replace it for you at no charge. If this does not fix the problem, you will have a new cluster at no charge. This is a copy of the GM bulletin.

#07187C: Special Coverage Adjustment - Instrument Panel Cluster Gauge Needle Function - (Mar 20, 2009)

This special coverage covers the condition described above for a period of 7 years or 70,000 miles (110,000 km), whichever occurs first, from the date the vehicle was originally placed in service, regardless of ownership.

Dealers are to replace the instrument panel cluster after the condition has been verified. The repairs will be made at no charge to the customer.

For verified failures between 70,001 miles (110,001 km) and 80,000 miles (130,000 km) on U.S. vehicles, dealers are to provide the customer with an instrument panel cluster (IPC) only. Any additional costs, including labor to replace the instrument panel cluster, will be the responsibility of the customer. Dealers are responsible for the return of the customer's IPC back to the Electronic Service Center.

For vehicles covered by Vehicle Service Contracts, all eligible claims with repair orders on or after September 28, 2007 for 2003-2004 model year vehicles, and March 23, 2009 for 2005 model year vehicles, are covered by this special coverage and must be submitted using the labor operation codes provided with this bulletin. Claims with repair orders prior to September 28, 2007 for 2003-2004 model year vehicles, or March 23, 2009 for 2005 model year vehicles, must be submitted to the Service Contract provider.

Involved are all 2003 and 2004 model year and certain U.S. 2005 Cadillac Escalade, Escalade ESV, and Escalade EXT; Chevrolet Avalanche, Silverado, Suburban, and Tahoe; and GMC Sierra, Yukon, and Yukon XL vehicles built within the following VIN breakpoints: 51100014-51247028 / 5E100002-5E223209 / 5F800001-5F882297 / 5Z100003-5Z224691

As for the turbo charging kit, you can log on to this link http://www.cartuning.ca/products/ and they should be able to help you modify there 6.2L turbo kit for the Escalade to work on your 5.3 Sierra by dropping the boost pressure with a simple waste gate swap. Yes they can Dyno tune your ECM for the extra Boost, if you keep the boost around 6 PSI, you should be good to go without any ECM tuning, but you are going to have to do some modes on your transmission. At 6PSI, that should give you another 30%HP to what you have at your rear wheels. Power output is 285-295 hp stock so your looking at 370-383 HP with an intercooler. Good luck and give and give Cartuning Performance a call.
 


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