4.8 bored to 5.7 piston size

[Ziegelsteinfaust]

I have decided to put the 383 in my truck back into my Camaro eventually here. So it needs to be replaced, and I have decided on a 327 style engine. This is do to the way I like to drive, and my resultant 4.88 gears.

Does boring a 4.8 or 5.3 to 5.7 bore size excessively reduce life span of the engine? Or if done right no out of normal problems will likely pop up? Hp goals are 400-425hp range. My goal is more endurance then all out power type of concept.

According to my gear ratio calculator my rpm at 75 will be between 2500, and 2800 rpm. Depending on convertor style I choose rather lock up or non lock up, and trans option I go for. To be honest I almost went with 3.73 gears, and a th400 in my truck. Instead of using a smaller motor, and overdrive. I love the sound of a small block at 3000 rpm. So I commited to a work around instead

I had a 4.8 with a LS6 cam in a 07 GMC rcsb with 4.56 gears, and I would like to recreate it with a little more pull. My truck is lighter so I am hoping it works out as well as I remembered. The 07 was a pig at 4800, and I am hoping I could get my 83 step to a good bit under 4000 with fiberglass. I need to weigh it, but I have been the lazy.

If I get a 4.8, and a 4L80 combo. Does it matter if it is from a 2500 van, or if I piece it togather. Meaning besides the wiring harness, and tuning. Does it give fits or headaches I should be aware of?

[MySons68C20]

"Displacement wise, the 4.8L is to the 5.3L what the original 283 was to the 327 small-block (technically 293 versus 325 ci). Given the bore and stroke of each, a better comparison might be the 327 and larger 350, as the 4.8L and 5.3L share the same bore size of 3.78 inches while the 4.8L makes due with a shorter 3.267-inch stroke (down from the typical LS stroke of 3.622 inches). Since the 4.8L and 5.3L share the same block (externally marked 4.8L/5.3L), not to mention the same heads, intake, and other external features, it is difficult to distinguish between the two. More than one enthusiast has purchased what he thought was a 5.3L, only to receive the smaller 4.8L in its place. Internally there are distinct differences, the most obvious being the use of flat-top pistons in the smaller 4.8L."

Quote from Motortrend

Here is the link for the whole article https://www.motortrend.com/how-to/4-...e-ls-slugfest/

Go with a 5.3 or 6 liter. We have a 5.3 in my sons 86 K10 with a BTR stage 3 cam, Edelbrock Pro Flo 4 fuel injection in front of the 700R4 and it rips.

[mongocanfly]

I agree...5.3 or 6.0...my LQ9 has plenty of power...

[Ziegelsteinfaust]

I need to cut down on low to midrange torque especially so it is easy for me to drive the way I want it too. As I plan to play around rally cross style, and have chosen my path to get there. Also I want to run in real rally crosses. It will be in the unlimited class or open. Which can be for cars that don't fit in the rules, and it would be for fun only either way.

The 5.3 and the 6.0 yes both make more power, and with less add-ons.

So I need the power graph of the 4.8 so I can control the rear end. The truck will be limited on many items namely tires as a compromise to my total plus operating budgets. Also so I do not want to over power the tires at the slightest throttle blip. Which will be alot easier with the 5.3, but especially the 6.0.

A neutered 5.3 or 6.0 technically do what I want, but they would be way less efficient at DD. Especially when neutered on torque to model my ideals. Where the 4.8 would be in it's zone much more effectively as per MY goals.

GAS is $4 dollars a gallon, and I want to be able to drive the truck. The 4.8 with OD will be much more acceptable with my 4.88's then the 6.0 would be.

I have had over powered vehicles, and done the same stlye driving before. It is a knife edge by comparison, and takes the a lot of joy out of hard driving. Since you always have to be on point. To much throttle. You sink the tires or spin out to easily. The 4.8 requires more throttle to do the same things, and thusly safer.

[Ziegelsteinfaust]

Originally Posted by mongocanfly

I agree...5.3 or 6.0...my LQ9 has plenty of power...

I am sure it does.

Your goals are likely alot different then mine, and you have chosen based on your wants.

[Ziegelsteinfaust]

Originally Posted by MySons68C20

"Displacement wise, the 4.8L is to the 5.3L what the original 283 was to the 327 small-block (technically 293 versus 325 ci). Given the bore and stroke of each, a better comparison might be the 327 and larger 350, as the 4.8L and 5.3L share the same bore size of 3.78 inches while the 4.8L makes due with a shorter 3.267-inch stroke (down from the typical LS stroke of 3.622 inches). Since the 4.8L and 5.3L share the same block (externally marked 4.8L/5.3L), not to mention the same heads, intake, and other external features, it is difficult to distinguish between the two. More than one enthusiast has purchased what he thought was a 5.3L, only to receive the smaller 4.8L in its place. Internally there are distinct differences, the most obvious being the use of flat-top pistons in the smaller 4.8L."

Quote from Motortrend

Here is the link for the whole article https://www.motortrend.com/how-to/4-...e-ls-slugfest/

Go with a 5.3 or 6 liter. We have a 5.3 in my sons 86 K10 with a BTR stage 3 cam, Edelbrock Pro Flo 4 fuel injection in front of the 700R4 and it rips.

To much mid range torque comparer to a 4.8. Which would either be unnoticed in a 4x4 or highly welcomed depending on point of view.

In the article the difference is 36lbft. Which would represent a 10% gain over a 4.8 roughly. Also I hope to move the power band up a hair to the 4500-6500 area so I have a wider margin on loose or slippery roads.

But in a 4.88 geared C10 bombing dirt roads. In my opinion, and with me behind the wheel. Doing stupid S*** a 47 year old man should not be doing. Not an ideal choice.

This truck has been a fantasy truck of mine for quite a few years, and now I finally get to build it. It is not about HP/TQ numbers, but rather a whole package. One that is quick on the streets, and fast on the dirt.

[TATE228]

bore size 4.8/5.3 is 3.78", bore on 5.7 is 3.89".

[Ziegelsteinfaust]

Originally Posted by TATE228

bore size 4.8/5.3 is 3.78", bore on 5.7 is 3.89".

Yes, but how well do the 4.8/5.3 last at the larger bore size.

People seem to do it, but is there any word on reliability?

[MySons68C20]

"Although most 5.3L LS blocks are cast iron, GM manufactures aluminum versions for the LS4, LM4, and L33. Like iron 5.3L blocks, the aluminum units share the same 3.780-inch bore. Unlike its iron counterparts that can be bored to 3.900 inches, the iron liners in aluminum 5.3L blocks can only be opened up .010"

.030 over is common on the iron blocks and you should not have any reliability or overheating issues.

[Ziegelsteinfaust]

Originally Posted by MySons68C20

"Although most 5.3L LS blocks are cast iron, GM manufactures aluminum versions for the LS4, LM4, and L33. Like iron 5.3L blocks, the aluminum units share the same 3.780-inch bore. Unlike its iron counterparts that can be bored to 3.900 inches, the iron liners in aluminum 5.3L blocks can only be opened up .010"

.030 over is common on the iron blocks and you should not have any reliability or overheating issues.

Thanks,

Do you have a opinion on early vs later computers or the 24x vs 48x sensors is it? I do not want dodge, and early ones litter pick a part.

[LS short box]

If you go 24 tooth you only need one ecm for the engine and trans control assuming you are going to run an auto. 58 tooth requires two ecm's, one for the engine and one for the trans.
I've run booth 24 tooth engines and 58 tooth engines in hot rods. Both have worked well.

[Ziegelsteinfaust]

Originally Posted by LS short box

If you go 24 tooth you only need one ecm for the engine and trans control assuming you are going to run an auto. 58 tooth requires two ecm's, one for the engine and one for the trans.
I've run booth 24 tooth engines and 58 tooth engines in hot rods. Both have worked well.

I have to run a auto due to knee issues. I drove a Fiesta with a stick, and it drove me mad in about 20 minutes in traffic.

I am thinking I will go for a 4L80. Would that change up the choice at all of early vs late computer styles.

[MySons68C20]

No

[Duck1]

Originally Posted by Ziegelsteinfaust

I have decided to put the 383 in my truck back into my Camaro eventually here. So it needs to be replaced, and I have decided on a 327 style engine. This is do to the way I like to drive, and my resultant 4.88 gears.

Does boring a 4.8 or 5.3 to 5.7 bore size excessively reduce life span of the engine? Or if done right no out of normal problems will likely pop up? Hp goals are 400-425hp range. My goal is more endurance then all out power type of concept.

According to my gear ratio calculator my rpm at 75 will be between 2500, and 2800 rpm. Depending on convertor style I choose rather lock up or non lock up, and trans option I go for. To be honest I almost went with 3.73 gears, and a th400 in my truck. Instead of using a smaller motor, and overdrive. I love the sound of a small block at 3000 rpm. So I commited to a work around instead

I had a 4.8 with a LS6 cam in a 07 GMC rcsb with 4.56 gears, and I would like to recreate it with a little more pull. My truck is lighter so I am hoping it works out as well as I remembered. The 07 was a pig at 4800, and I am hoping I could get my 83 step to a good bit under 4000 with fiberglass. I need to weigh it, but I have been the lazy.

If I get a 4.8, and a 4L80 combo. Does it matter if it is from a 2500 van, or if I piece it togather. Meaning besides the wiring harness, and tuning. Does it give fits or headaches I should be aware of?

save your money a buy a 6.0. better yet. If not add the price of the new 5.7 pistons, machine shop work. Pay me that for my 6.0 and leave your 4.8)5.3 as a core.👍😉

[Tom]

No, boring the engine bigger does not reduce its life span.

I think a 3.9" bore with the short stroke would be a cool ass combo myself.

[Ziegelsteinfaust]

Originally Posted by Tom

No, boring the engine bigger does not reduce its life span.

I think a 3.9" bore with the short stroke would be a cool ass combo myself.

I am big fan of revvy motors, and I love 302's or 327's at 3000 rpm cruise.

Not that I haven't owned a few different big blocks, and throughly enjoyed them. 2 455 Buicks, 1 454, 1 496, 1 460, and 2 FE's which kind of sort of technically are big blocks too.

The concept for my truck is to have a rally cross or dirt road bombing truck. So the lack or torque where I presumably will be "racing" makes the truck safer to push harder. That way the tires won't break loose as easily on slick sandy dirt roads where I go. I will do every suspension mod I can think of for the street, but I will run AT tires at all 4 corners. The only difference I will do is add longer leaf springs for a more progressive feeling on dirt when I hit some bumps or washboard. Where on the street shorter springs help with firmness coming out of a corner.

This is a concept truck that started 10 years ago for me, and partially did up a C20 long bed to the idea. Well I fell in love with it. So I intend this to be a full expression of my talents, and ideas.