5.3 vs LS1?

[chevy72blu]

Hey folks,

In my hunt for a 5.3, I came across a local guy with an LS1/4l60e combo (complete) with 60k miles. He is actually interested in other motors/other stuff I have laying around so I could trade straight across (cash value around 4k). Since I planned on spending around $3200 for a motor/trans/harness/pcm flash this is a step up in budget but the trading makes it a lot easier.

My question is - is there any reason NOT to go with the LS1? It is my understanding that "go fast" parts are cheaper for it, but my goal with this build is just to have a reliable DD. I am aiming for 20+ MPG in my mostly stock 72'. Of course, we all say that... and then wish we had more power when standing on it

Is there a significant difference in power between the LS1 and 5.3 Vortec? Is there a significant difference in gas mileage? I know that the aluminum block is lighter, but that kind of seems like attacking the mountain with a tooth pick considering how heavy the beast is anyway.

I did a search, but didnt get answers to my specific questions. Sorry for the dumb ones folks... This is all new to me! I hope everyone enjoys their Sunday.

[mooseknuckles]

I'd trade in a heartbeat.....

[Mr. 250r]

Quick 5.3 info

LC9 / LH6 / LH8 - Gen IV - Truck - Aluminum - 2005-2009+ - 326 hp / 350 ft-lbs
Little brother of L76

LMF / LMG / LY5 - Gen IV - Truck - Iron - 2007-2009+ - 326 hp / 350 ft-lbs
Little brother of LY6

LM7 / L59 - Gen III - Truck - Aluminum - 2003-2007 - 310 hp / 335 ft-lbs
First all aluminum 5.3

LM7 / L59 - Gen III - Truck - Iron - 1999-2007 - 295 hp / 335 ft-lbs
Little brother of LQ4


Quick 5.7 info

LS6 - Gen III - Car - Aluminum - 2001-2005 - 405 hp / 400 lb-ft
H.O. version of LS1

LS1 - Gen III - Car - Aluminum - 1997-2004 - 350 hp / 375 lb-ft
First Gen III V8

Just depends on what year either motor is that being said you can always bore the 5.3 out to a 5.7 but you cannot bore a 5.7 to take advantage of the 6.0 4.00in bore one smaller reason not to go with the LS1 is if something happens to the block they are much more expensive to replace than the 5.3 block in the end both can make great power hope this little amount of info helps and here's a big ol link to some more

The two links provide a massive amount of info from power output to weight and dimensions, problems from the factory and what motor replaced etc etc etc

http://www.pirate4x4.com/tech/billav...SPrimer/Part1/
http://www.pirate4x4.com/tech/billav...SPrimer/Part2/

[Snowbound]

Since a complete 5.3 engine trans combo is $1500ish and an LS1 combo is $3500ish ( what I've seen advertised anyways ), my thoughts are that you could do ALOT of upgrades to the 5.3 for the extra $2k you are saving.

Plus, are there not complications with the car style accessory drives that need changed to work in a truck?

[whitels1]

All the internal parts are the same size except the pistons are smaller in the 5.3, bore is 3.78 , and it's an iron block. You always have the option of boring the 5.3 block to 3.898 and using ls1 pistons to make it an iron block LS1. The ls1 heads do flow better than the 5.3 but LS1 heads can be found on craigslist all day for 100 bucks. Plus the truck accessories will be the way to go.

[chevy72blu]

Originally Posted by Snowbound

Since a complete 5.3 engine trans combo is $1500ish and an LS1 combo is $3500ish ( what I've seen advertised anyways ), my thoughts are that you could do ALOT of upgrades to the 5.3 for the extra $2k you are saving.

Plus, are there not complications with the car style accessory drives that need changed to work in a truck?

I was wondering about that also. The point of doing the trade would be for simplicity, but if i have to replace all of the accessories then it would probably be a deal breaker.

I always thought that the LS1s were significantly more powerful from the factory than their truck equivalents... Seems like a more to go through without much benefit other than the cool factor.

Where are you guys finding complete motor/trans combos for $1500? I've been calling all over the country around 3-4 k seems to be the average for low miles units. I made another thread about it... Perhaps im just not looking hard enough?

[chevy72blu]

Well I went and looked at the LS1 today and I must say, the brackets and arrangement didnt look all that different from the 5.3 setup. The motor and trans looked great.

AC compressor wasnt attached, but I can see where it would swing out a bit and perhaps contact the frame.

The P/S pump (driver side, above the alternator) wouldnt be a problem

The alternator (driver side, below the P/S pump) doesnt look like it would cause issues either.

Kwik performance makes a bracket that raises the compressor up near the valve covers (almost $200). I believe Dirty Dingo makes one also.

Buuuuuuuut, the LS1 is also drive by cable. I was just starting to get comfortable with the idea of DBW... I havent seen a build thread that mentioned DBC. Is it a pain to tackle?

[gringoloco]

DBC is easier, just hook the cable to your pedal (71-72) or convert to cable style for 67-70.

The alternator might cause issues, but definitely looks better than the truck style mounting.
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[clinebarger]

Originally Posted by chevy72blu

Well I went and looked at the LS1 today and I must say, the brackets and arrangement didnt look all that different from the 5.3 setup. The motor and trans looked great.

AC compressor wasnt attached, but I can see where it would swing out a bit and perhaps contact the frame.

The P/S pump (driver side, above the alternator) wouldnt be a problem

The alternator (driver side, below the P/S pump) doesnt look like it would cause issues either.

Kwik performance makes a bracket that raises the compressor up near the valve covers (almost $200). I believe Dirty Dingo makes one also.

Buuuuuuuut, the LS1 is also drive by cable. I was just starting to get comfortable with the idea of DBW... I havent seen a build thread that mentioned DBC. Is it a pain to tackle?

Ive owned both & built many more, GET THE LS1. The DBC is easy....Dont let that scare you.

The aluminum 5.7L LS1 is NOISEY when cold....Or should I say noiser than a 5.3L.

[Kainedogg]

Since its a straight up trade for crap you may have wanted to get rid of anyway, I say go for it. As far as the comment about 5.3 heads being inferior, you have it backwards. Unless you have the LS6 version (not likely) then you don't have the favored 243 heads. However late model 5.3's came with 799's which are the equivalent to the 243's minus sodium filled valves which Chevy sells for $50 a piece. Go with the LS1, long tube headers, decent cam and stall and you will have an easy 400+ fly wheel hp.

[19seventeeCustom]

Originally Posted by clinebarger

Ive owned both & built many more, GET THE LS1. The DBC is easy....Dont let that scare you.

The aluminum 5.7L LS1 is NOISEY when cold....Or should I say noiser than a 5.3L.

I agree on both accounts, plus the low mount alternator and car intake are just icing on the cake.. much cleaner install than a high mount with a tall ugly
truck intake......plus aluminum block will shed even more weight from the swap.

[Super73]

I don't think anyone has focused on the advantage of the bigger bore of the ls1 vs 5.3. It helps to unshroud the valve and make more power.
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[Hart_Rod]

Good info on the advantages of the LS1 over the 5.3. I just picked up an LS1/4L60E out of 2002 Camaro Z28 with 24K miles (verified). I plan on replacing the 383 motor in my 68. Should this have the good heads? Where do I look for the markings? Thanks,

Rob

[68Stepbed]

Alot of guys are boring their 5.3's to a 5.7L for more displacement anyway. Plus, you'll have an aluminum block for less weight. I was going to look for a 5.3 myself, but when I found the LS1, I jumped on it quick.

Rob, that engine will probably have the 241 heads like my LS1 has. Just look at the front corners of the heads for the casting #'s. Be prepared for a disappointment in torque with a stock or mild LS1 compared to a 383. It will be the overall powerband of the Gen III/IV engines that you will notice.

[Hart_Rod]

Originally Posted by 68Stepbed

Alot of guys are boring their 5.3's to a 5.7L for more displacement anyway. Plus, you'll have an aluminum block for less weight. I was going to look for a 5.3 myself, but when I found the LS1, I jumped on it quick.

Rob, that engine will probably have the 241 heads like my LS1 has. Just look at the front corners of the heads for the casting #'s. Be prepared for a disappointment in torque with a stock or mild LS1 compared to a 383. It will be the overall powerband of the Gen III/IV engines that you will notice.

Thanks Matt. How much will a Maggie wake it up?

[clinebarger]

I had a MagnaCharger on a '98 LS1, 400+ ftlbs right off idle....You will love it!

[68Stepbed]

Originally Posted by Hart_Rod

Thanks Matt. How much will a Maggie wake it up?

Quite a bit. That would fit the bill nicely!!

[OneOffStroker]

Also, nobody hit on the fact that you mentioned this is for a pickup and you want decent gas mileage. Redline horsepower wasn't in your intial description, which is why I say you should go with a hybrid LS1/5.3L. Get the LS1 from your friend on trade, and put a truck intake and accessories on it. The truck intake will get you gobs of torque, which seems to be something you want.

[Kainedogg]

Originally Posted by OneOffStroker

Also, nobody hit on the fact that you mentioned this is for a pickup and you want decent gas mileage. Redline horsepower wasn't in your intial description, which is why I say you should go with a hybrid LS1/5.3L. Get the LS1 from your friend on trade, and put a truck intake and accessories on it. The truck intake will get you gobs of torque, which seems to be something you want.

That's actually more of a myth. Truck intake makes a little more torque but not worth the hp you lose with the LS1 that can actually spin up to higher rpms (nothing stratospheric) and be limited by the truck intake. When we think of hybrid we want something actually beneficial, like an LQ9 with L92 heads, not punish a good motor by limiting its potential through out the entire rpm range. It would make more sense...in my opinion...to run it as is and if the OP's needs change then a cam swap can be the end all.

[BR3W CITY]

The truck intake really ISN'T as bad as it gets a wrap for, but the only people who really ever run a cam that benefits it are 4x4's and bigger truck swaps. The lq4 & lq9 have 317 heads, which with the truck intake (Stock obviously) and a custom cam with a shorter duration and low LSA to make stump pulling torque.
The 5.3/ls1 with a truck intake really isn't beneficial tho.


and btw, I didn't see what year LS1 it was, but make sure its not blowing oil or has wrist pin issues if its an early model, and if its a 98 the computer and wiring is kind of a b**ch.

[Super73]

I think there are cass where the truck intake flat out works: http://ls1tech.com/forums/dynamomete...ock-heads.html


I and many others have been saying it for years, it's all about the combo, not one specific part. Go look around performance trucks, there have been many dyno's showing the truck intake moping p on the ls6 intake.


Just sayin...
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[Hart_Rod]

Originally Posted by chevy72blu

Well I went and looked at the LS1 today and I must say, the brackets and arrangement didnt look all that different from the 5.3 setup. The motor and trans looked great.

AC compressor wasnt attached, but I can see where it would swing out a bit and perhaps contact the frame.

The P/S pump (driver side, above the alternator) wouldnt be a problem

The alternator (driver side, below the P/S pump) doesnt look like it would cause issues either.

Kwik performance makes a bracket that raises the compressor up near the valve covers (almost $200). I believe Dirty Dingo makes one also.


Did you get the motor? Drive by cable is simpler to set up.

Great info guys! What cam and springs would be good to install that would work work well with the future addition of a Maggie style blower?

Buuuuuuuut, the LS1 is also drive by cable. I was just starting to get comfortable with the idea of DBW... I havent seen a build thread that mentioned DBC. Is it a pain to tackle?

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[5150.4.67]

I went with a 6.0 (even though I had a 5.3 sitting in the garage). After many hours of surfing LS1tech, I decided a 6.0 has A LOT more potential on tap for future mods..........