Help building my First LS 5.3
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Teching In
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Help building my First LS 5.3 Hello. I am new to this site. Also new to building a 5.3. I have had lots of old school GM engine. So I just have to get some education on sourcing the right parts and building this engine for what it is supposed to do. I have bough ten all the books on the engines. So assembly is not a problem. Also have access to some of the special tools. I am building LM7 5.3 for a big heavy 4 door Jeep / Rock Crawler. I drive it on the highway and street .it weighs about 6.500 Lbs. I have lots of gearing so I'm good with my plan of a 5.3 and a 4L60 . The whole jeep wiring will be eliminated and rewired,no more Canbus to deal with. It will be like building a hot rod. I am looking for about 385 hp or so. This is what I have collected so far,5.3 that will need to be rebuilt it ran fine. Had 130.000 miles on it. I have a new LQ9 cam.New 243 heads with the none sodium valves. So I need help sourcing parts at a good price. I need some valve train parts. The proper flat top pistons, and all the other parts I will need to refresh this motor. I'm thinking of running a FI -Tech fuel injection system. .i need a stand alone system. Do you guys like my cam choice. I already have it so I thought it's going to be good enough . Also need a contact ti build me a strong 4L60 trans . I have one just want it redone. I live in Canada but have a US address to get my parts shipped to. I'm in the Spokane WA area. Thank you people for your time. Rob. Oh one more thing. Yes the whole Dash will be coming out too. I have to build one of those too. Will still be wanting Heat and Aircond. And power door locks and Windows. So will be needing to source a dash guy to buy parts etc. was looking at 12 volt guy stuff.
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Pump the brakes lol.
-130k miles, it won't need a rebuild. You might end up doing more harm than good.
-243 heads will lower compression, you'll lose only a little bit of power, but a fair amount of torque.
-Skip OEM cams. Get a real cam that will make the power curve you need.
-The 4L60e isn't a very good trans. They have several problems. Also, you would need a standalone that can do transmission control.
-A stock 4L80e will outlast any mild built 4l60e.
-FITech system is like a self-adjust carb. They're not the most ideal. For something you don't want to mess with, they will work fine.
-130k miles, it won't need a rebuild. You might end up doing more harm than good.
-243 heads will lower compression, you'll lose only a little bit of power, but a fair amount of torque.
-Skip OEM cams. Get a real cam that will make the power curve you need.
-The 4L60e isn't a very good trans. They have several problems. Also, you would need a standalone that can do transmission control.
-A stock 4L80e will outlast any mild built 4l60e.
-FITech system is like a self-adjust carb. They're not the most ideal. For something you don't want to mess with, they will work fine.
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Teching In
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Thanks for you input. Still thinking about the cam . But I think I will do the pistons some bowl blending on the heads. I will be using the Fi tech manifold etc. the whole system incl trans connection for programming. I think Beefed up L60 should handle this little power plant. Also 60 has a lower first gear. I use more offroad than the street. I trailer it on long trips. It's a 2007 but only has 30.000 miles on it. What cam were you thinking. When I take motor apart will find out if it needs going over. Thanks again.
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The FITech manifold loses power/torque everywhere below 6000 RPM compared to a stock 5.3 truck manifold. Not to mention, the FITech is geared towards ease of use and safety and shys away from optimal power/torque. In a 6000 lb vehicle, expect it to be a dog.
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Thanks for that info i was wondering about there system. i have the factory system still so it will work. there is a tuner in Spokane that ca make me a stand alone system . i have lots to think about for the 5.3 got a suggestion for a cam, for my application. Thanks for your help But i do like the cool looking manifold FI has lol
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From: Ohio
Gen 4 truck intake is going to be your best bet for power/torque on a budget that still makes excellent cruise/pulling torque.
Up to 4000 RPM, it makes more torque than most aftermarket manifolds as well.
Stock PCM/harness will do what you want. If you're going to spend the money, the Holley does trans control as well.
The FITech manifold is the same Chinese manifold that over 30 companies claim to be their own.
They are riddled with issues. They make poor torque and are noisy. Some people have even had them come apart.
Up to 4000 RPM, it makes more torque than most aftermarket manifolds as well.
Stock PCM/harness will do what you want. If you're going to spend the money, the Holley does trans control as well.
The FITech manifold is the same Chinese manifold that over 30 companies claim to be their own.
They are riddled with issues. They make poor torque and are noisy. Some people have even had them come apart.
385 crankshaft horsepower should be easily obtained by just throwing a cam in and some super mild port work on the 862/706 heads with a 2.0 intake valve. I agree with the poster above, unless there is something wrong, it won’t take much to get the desired hp out of it.
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Thanks for that info i was wondering about there system. i have the factory system still so it will work. there is a tuner in Spokane that ca make me a stand alone system . i have lots to think about for the 5.3 got a suggestion for a cam, for my application. Thanks for your help But i do like the cool looking manifold FI has lol
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If you want to stay with a stock cam to keep your stock springs, lifters, etc - get a ‘00 LS1 cam, the last four of their part numbers will 0965 or 0968. Otherwise, spend the $350 to get yourself real cam. And don’t waste any time or money on stand alone EFI, the stock PCM will do more than you’ll ever need.
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Thread Starter
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Plans are coming togeather because I went on this site and got good info from hands on guys from this forum. I will buying a complete crane cam and valve train that all matches. Going with a factor ECM got a good tuner in Spokane. Just going to look for gen 4 truck manifold. Or will look into aftermarket truck intake. Got any sugestions? I will be running some block style headers. Whatever's works on a jk jerk LS swap. Good ones not cheap ones. I'm from Canada our money sucks buying a part for $1,000 Us dallars == $1.400 -$1.500 because of exchange on the dallar and taxes when I bring it into Canada. So we have to really shop around.Rob
I'm going to also say that your idea of running a 4L60E should be revisited. They are exceptionally weak units with known issues with the planetaries, output shaft, aluminum input drum, sunshell, input sprag, insufficient internal space for increased friction surface area, and many, many, other weaknesses. You can also expect transmission case life to be very short if you plan on offroading with larger tires. The center support in that unit will damage the cast in case lugs requiring upgrades to address it, or case replacement. You would be far better served by starting with any other transmission except the 700R4/4L60/4L60E family. You can WASTE a bunch of money trying to "beef one up" but in the end, after spending thousands of dollars, you will still have a transmission that is far weaker than an all stock 4L80E.. If you don't do much freeway driving, you could also use a 3 speed trans such as the TH-350, or TH-400. Both of those in stock form are significantly stronger than a 700/60E is, or could ever be.. If you use the TH-350 you will find that it is shorter in length and this will allow you to run a driveshaft that is a little longer in the rear. Using an 80E is going to have you using a very short rear driveshaft.. So short that the angles will eat up U-joints. You can expect that you will be changing U-joints out on a fairly regular basis if you drive the vehicle a significant amount of miles.
If you want to stay with a stock cam to keep your stock springs, lifters, etc - get a ‘00 LS1 cam, the last four of their part numbers will 0965 or 0968. Otherwise, spend the $350 to get yourself real cam. And don’t waste any time or money on stand alone EFI, the stock PCM will do more than you’ll ever need.
Plans are coming togeather because I went on this site and got good info from hands on guys from this forum. I will buying a complete crane cam and valve train that all matches. Going with a factor ECM got a good tuner in Spokane. Just going to look for gen 4 truck manifold. Or will look into aftermarket truck intake. Got any sugestions? I will be running some block style headers. Whatever's works on a jk jerk LS swap. Good ones not cheap ones. I'm from Canada our money sucks buying a part for $1,000 Us dallars == $1.400 -$1.500 because of exchange on the dallar and taxes when I bring it into Canada. So we have to really shop around.Rob
I'm going to also say that your idea of running a 4L60E should be revisited. They are exceptionally weak units with known issues with the planetaries, output shaft, aluminum input drum, sunshell, input sprag, insufficient internal space for increased friction surface area, and many, many, other weaknesses. You can also expect transmission case life to be very short if you plan on offroading with larger tires. The center support in that unit will damage the cast in case lugs requiring upgrades to address it, or case replacement. You would be far better served by starting with any other transmission except the 700R4/4L60/4L60E family. You can WASTE a bunch of money trying to "beef one up" but in the end, after spending thousands of dollars, you will still have a transmission that is far weaker than an all stock 4L80E.. If you don't do much freeway driving, you could also use a 3 speed trans such as the TH-350, or TH-400. Both of those in stock form are significantly stronger than a 700/60E is, or could ever be.. If you use the TH-350 you will find that it is shorter in length and this will allow you to run a driveshaft that is a little longer in the rear. Using an 80E is going to have you using a very short rear driveshaft.. So short that the angles will eat up U-joints. You can expect that you will be changing U-joints out on a fairly regular basis if you drive the vehicle a significant amount of miles.
I'm going to also say that your idea of running a 4L60E should be revisited. They are exceptionally weak units with known issues with the planetaries, output shaft, aluminum input drum, sunshell, input sprag, insufficient internal space for increased friction surface area, and many, many, other weaknesses. You can also expect transmission case life to be very short if you plan on offroading with larger tires. The center support in that unit will damage the cast in case lugs requiring upgrades to address it, or case replacement. You would be far better served by starting with any other transmission except the 700R4/4L60/4L60E family. You can WASTE a bunch of money trying to "beef one up" but in the end, after spending thousands of dollars, you will still have a transmission that is far weaker than an all stock 4L80E.. If you don't do much freeway driving, you could also use a 3 speed trans such as the TH-350, or TH-400. Both of those in stock form are significantly stronger than a 700/60E is, or could ever be.. If you use the TH-350 you will find that it is shorter in length and this will allow you to run a driveshaft that is a little longer in the rear. Using an 80E is going to have you using a very short rear driveshaft.. So short that the angles will eat up U-joints. You can expect that you will be changing U-joints out on a fairly regular basis if you drive the vehicle a significant amount of miles.
1. Install a good external cooler. A dedicated fan for said cooler probably wouldn’t be a bad thing.
2. Get your final drive/tire size combo somewhere in the 24 inches per driveshaft revolution count if not lower.
3. Stick with a stock or very low rpm converter. Higher rpm converters build heat quicker.
4. A large fluid capacity pan
Gearing and and heat dissipation is what will keep that transmission alive. I don’t think your so much a risk to break components inside as much as you’re likely to burn up components from heat.
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Teching In
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Got me thinking about this trans. I will do more research . I have the trans so I thought I would just get it beefed up to handle 400 hp or so. I'm running 40 inch tires 5.13. But when I'm wheeling I have lots of low gears to choose from. It's a rock crawler so it has good drive shaft double Cardin 1350 joints. Lots of choices , I will do more research and do it right the first time.
Got me thinking about this trans. I will do more research . I have the trans so I thought I would just get it beefed up to handle 400 hp or so. I'm running 40 inch tires 5.13. But when I'm wheeling I have lots of low gears to choose from. It's a rock crawler so it has good drive shaft double Cardin 1350 joints. Lots of choices , I will do more research and do it right the first time.
Again as for your motor you don't need to do a full rebuild on it to get 385 hp, in fact I'd be tempted to run it as is. Stock they are rated for 275-285. While I have never dynoed a 5.3 if they are anything like the 5.7 HP wise they are probably closer in reality to 300. If you didn't know GM when the LS platform came out was known to have a large number of factory freaks running around, particularly in the 5.7 motors. In short there were plenty of 5.7 fbodies which should have been making 260-275 at the wheels stock that were actually making 300ish if not more. Timesheets backed up these numbers with some bone stock cars running low 13's to high 12's in the quarter mile STOCK trapping well over 105 mph. So I wouldn't get too wrapped up in doing alot of work to it if it runs ok now.
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Those 5.7 F bodies that had "extra" power had LS6's in them. Apparently GM ran short of LS1's, so they dropped LS6's in their place! Build cost difference was minimal, so GM didn't lose much on the deal.
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Thanks guys. Little info on myself. I'm an older guy and have have fords and Chevys. I'm a Chevy guy. I have had lots of small blocke cars,69 Z28 302 4 gear. Also 70Z28 LT1. And so many cars and trucks I have lost count. I had a 2000 Yukon 5.3 but just did a few bolt ons. Also Ls7 big block and 3 or4 old school 383. But this will be my first LS build . The 4 door jeep now has a 202 Hp **** box Dodge Van Motor. I did a tune and TBS and intake. They are junk . So that is why I'm gutting the Jeep and going with LS engine and a build 4L60 or ? The jeep now runs good on the highway. But when it hits a hill its works. And the gas Mileage sucks. This jeep I'm redoing because I rolled it and is a good time to do it while it's apart. The new drivetrain will be using an Atlas 2 or 4 speed transfer case. With a built up transmission. I have wheeled the **** out of this dodge drivetrain , have bigger pan and cooler on trans and coolers also a gear reduction in the factory auto. Never had a problem overheating running 40 Inch tires. It also weighs about 6,200 lbs. I have lots of LS engine books. But you guys are very helpful. You guys got any recommendations for a good parts sources at good prices?