5.3 to 383 stroker

[comicaltatertot]

So I didn't know where to post this and I hope that this is right place, I am just looking for some help. I have a 2005 GMC Sierra with a 5.3 it is an L33 so it as the aluminum block and 799 heads. I am just lookin to do something different than everyone else. So when doing some reading I ran across truckin who did a 5.3 and turned it into a 383 stroker.
Doing some more research I found the kit from probe industries has a 4" crank, 6.2" H beam rods and pistons for a 3.902 bore.
My question is do you think this would be a reliable engine after it has been bored out and clearanced? I am looking for about 500hp
Also on 799 heads would they support up to 500hp? I know they would need a valve spring upgrade. Or would it be safer to send them out to like TEA to get them done?
Anywho any help on this would be great. Thanks

[Marv D]

I have that same stroke / bore in a LS1 block in my sand rail. With stock LS1 853 heads, a mild comp cam (223/229 @ 0.050 .586 lift) it made 460 HP but more important,, 450 pounds of torque from 3200 and above , with a 480ft lb peak.
http://www.small-block-chevy.com/ima...LS1stroker.mp4

But... This is not emissions tuned or regulated motor with no cats, 1-3/4" buggy headers and Gibson shortie mufflers. But stock injectors, a DelPhi computer and a truck intake manifold.

One thing to watch out for is the 6.2" rod deal was the early versions of the LS 383 and is not that common any more. More of the 383 LS strokers use the 6.125" rods. In fact I had to order a 1 change custom piston from JE to use the 6.2" rods in a overbore on this motor It's amazing the places sand can find it's way in to! (Pistons were cheaper than all new liners) So just be aware that if you step out of the 'normal' box,, it can get in to your pocket later. Most of the Eagle, Lunati and upper end LS stroker kits these days use the 6.125" rod. Just be aware of that

[crazy longhorn]

I am new to the Ls game, but will toss this out....I have heard it said that you can bore the IRON 5.3 's 3 mm & achieve your goal? The aluminum blocks, I don't believe have enough liner thickness to accommodate? Back to Marv, for more info Longhorn

[comicaltatertot]

Ok I see what you are saying about the rods. Do you think a kit with 6.125" rods would work in that motor? I only ask because being .075 shorter might cause problems?? I don't know just something for me to think about.

I will have to check into that to make sure, the worst thing would be to tear into it only to find that liner is too small the hard way, then I wouldn't have a block anymore which would suck really bad. Maybe I will look into boltons/boost too I mean I want to have a 383 I just don't want to ruin my block at the same time.

Thanks for the input

[Marv D]

You should get this moved into the LS swap section. There are guys WAY smarter than I ,, including CL.. I didn't catch the aluminum block,, 5.3 iron block will go to 3.904,, the aluminum block 3.780 sleeves no way are going to take that massive overbore.

So as an option,, how about looking around for a LS-1 block. They are getting to be like the beloved Gen I SBC as in they are now appearing in a back yard near you.

[comicaltatertot]

Originally Posted by Marv D

You should get this moved into the LS swap section. There are guys WAY smarter than I ,, including CL.. I didn't catch the aluminum block,, 5.3 iron block will go to 3.904,, the aluminum block 3.780 sleeves no way are going to take that massive overbore.

So as an option,, how about looking around for a LS-1 block. They are getting to be like the beloved Gen I SBC as in they are now appearing in a back yard near you.

Ok cool sounds good. So is there a way to copy and paste this thread into the LS section? Or would I just have to create a new thread in the LS section?

[crazy longhorn]

Originally Posted by Marv D

You should get this moved into the LS swap section. There are guys WAY smarter than I ,, including CL.. I didn't catch the aluminum block,, 5.3 iron block will go to 3.904,, the aluminum block 3.780 sleeves no way are going to take that massive overbore.

So as an option,, how about looking around for a LS-1 block. They are getting to be like the beloved Gen I SBC as in they are now appearing in a back yard near you.

No way old man....I respect what you have to say I thought that you missed the alum block deal, & sent it back to you. I feel that you are far sharper than this man, & have played in the LS engines more than I have...(better man to lay the news)! Cable, can you send this to the LS side? Give the man the benefit, of all the guys playin? longhorn

[cableguy0]

Just saw this. Will move it to ls section.

[comicaltatertot]

Originally Posted by cableguy0

Just saw this. Will move it to ls section.

Awesome thank you!

[crazy longhorn]

Marv, or Cline , or Brew, will help you here.....as well as a few others Longhorn

[BR3W CITY]

Alright I'm here, I had to organize my herb n spice collection and that takes a while.


The aluminum 5.3's can take a certain level or boring, how much exactly will be determined by the thickness of the ductile iron sleeves in the block. The reason folks think you can't do so is twofold;

some folks think there is a thin wall of iron and a solid aluminum block which isn't true, the cylinder bores are always the same size (for the sake of discussion lets say 4.2")...what changes is the size of the sleeve in the bore. The 4.8 / 5.3 are the smallest displacement because of a thicker sleeve. Most of them can come up to around the 5.7L mark (chevy's cost saving way of being able to have more-cards in their deck than ever intended. There are odd-displacement versions, and weird all-iron and all-alum versions of LS architecture engines sitting all over the industrial landscape.

The second reason people think you can't, is a misunderstanding of true information. While you can't "bore a 5.3 out to a 6.0", you CAN in fact bore AND stroke a 4.8/5.3 engine to a maximum displacement of more than 6L. You CANNOT however bore them to 4", or run the heads or internals from the 6L+ blocks.

Which heads you do choose to run (and how they are prepared) will be somewhat of a function of the resulting compression you're aiming for, as part of the valve/deck/piston relationship. Most of the time these strokers are being built for all-motor builds which aim for high effort from the engine, meaning it needs compression, it needs to breath, and it needs to rev.

You'll need hardened pushrods, and I'd strongly consider replacing the o.e. lifters with LS7 ones (ALL currenty replacement GM ls lifters are LS7 design, you don't have to ask for them specificially, the part # has been replaced system wide). If your gonna be turning rpm's, then its a good idea to do a trunion upgrade to the stock rocker arms. DO NOT CHANGE THE ROCKER ARM GEOMETRY.

Cam and springs will also be determined by your goals and parts choice. Brian Tooly makes great titanium valve springs if you can boss up for them. They are one of the only springs that will keep seat pressure after long periods of low-ramp high-lift cams.

my brain is tired for now. Let me know what else you'd like to know, I can work out some more.

[Marv D]

BR, am I understanding you that the aluminum 5.3 is the same as the LS1 block? Wait, that's not 'exactly' what your saying I know. But the 5.3 would accept the LS1 sleeve? then all thats left is the 4" stroke. Would the Aluminum 5.3 block tolerate that?

I've just gotten my feet wet in this LS world and am just smart enough to know,,, it's not the 'future'
it's the NOW.

[comicaltatertot]

Thanks brew for the info I had never heard of Brian Tooley before but it is a pretty sweet place. So I actually just might stick with a cam swap. I know a stroker would be awesome, but this is my DD so I don't really want to have it down for very long either. On Brian Tooleys site it mentions that his cams can be used with stock valvetrain. But wouldn't it be safer to swap in new lifters, valve springs, rocker arms and pushrods? I was just looking at their stage 1 or 2 truck cam.

[clinebarger]

Not to offend anyone, But....383 stroker LS1's are obsolete. They were all the rage a few years ago....Especially Vette & F-body guys that thought their cars would flip over & burn if an Iron block was used

Why tear down a good engine just to use the block? When Iron 4" bore 6.0L blocks are widely available. Add in the fact you can build the long block without disabling your truck.

I vote for a 4" stroke, 4.030" bore 408 CI, Why build a smaller under-square engine for the same money. Plus you can run L92/LS3 heads with a 4" bore, Bigger valves, Better valve spacing, Bigger intake ports.

[comicaltatertot]

Originally Posted by clinebarger

Not to offend anyone, But....383 stroker LS1's are obsolete. They were all the rage a few years ago....Especially Vette & F-body guys that thought their cars would flip over & burn if an Iron block was used

Why tear down a good engine just to use the block? When Iron 4" bore 6.0L blocks are widely available. Add in the fact you can build the long block without disabling your truck.

I vote for a 4" stroke, 4.030" bore 408 CI, Why build a smaller under-square engine for the same money. Plus you can run L92/LS3 heads with a 4" bore, Bigger valves, Better valve spacing, Bigger intake ports.

Honestly that is what I was thinking though. My engine is totally fine just doesn't make sense for me to tear it down just for the block. I get all excited sometimes, then when I think about it more just doesn't sound as good
Would a 6.0 basically take up the same amount of space in the engine bay?

[clinebarger]

The 6.0L external dimensions are the same as any LS style engine.

[BR3W CITY]

Originally Posted by comicaltatertot

Thanks brew for the info I had never heard of Brian Tooley before but it is a pretty sweet place. So I actually just might stick with a cam swap. On Brian Tooleys site it mentions that his cams can be used with stock valvetrain. But wouldn't it be safer to swap in new lifters, valve springs, rocker arms and pushrods? I was just looking at their stage 1 or 2 truck cam.

If you wanna take your stock 5.3, do a few weekends worth of work and have plenty of power, its very doable. Cline ain't lying about the obsolescence either; most of the time the 383 LS builds are more about having a 383 and less about the actual power result.

I actually don't know anyone who uses the Tooley cams. We only use him for the valvetrain parts, but most of the cams we use now are custom grinds. I don't think anything is wrong with his, I just can't attest to their grinds.

Do you have a budget in mind for this build? 500hp at the crank is towards the top of what most N/A 5.3's are running. At that level on stock internals, your running a pretty aggressive cam, worked heads, long tubes, and a heck of a tune. You're probably looking at bumping compression as well, meaning you need a very close eye on PTVC and avoiding detonation.

[comicaltatertot]

Originally Posted by BR3W CITY

If you wanna take your stock 5.3, do a few weekends worth of work and have plenty of power, its very doable. Cline ain't lying about the obsolescence either; most of the time the 383 LS builds are more about having a 383 and less about the actual power result.

I actually don't know anyone who uses the Tooley cams. We only use him for the valvetrain parts, but most of the cams we use now are custom grinds. I don't think anything is wrong with his, I just can't attest to their grinds.

Do you have a budget in mind for this build? 500hp at the crank is towards the top of what most N/A 5.3's are running. At that level on stock internals, your running a pretty aggressive cam, worked heads, long tubes, and a heck of a tune. You're probably looking at bumping compression as well, meaning you need a very close eye on PTVC and avoiding detonation.

First question how is the "new" LT motors just an evolution of the LS? Is it due to a lot of things are the same except for like direct injection? I am just wonderin

And I was looking for 300-350 wheel hp with a 2-2500K budget. Really looking for a good torque increase (well good for 5.3) If I can keep the heads/springs stock that would be great. If not I could send my heads to TEA get like a Stage 1 for 799 heads, then look at a Vinci Butt Kicker cam

Regardless of what I do I did want to add headers, LS6 ported oil pump, LS2 timing chain, 3" cat back, replacement lifters, hardened pushrods, tune and probably replacement rocker arms. I just have to make up my mind on what to do with the motor.

Oh and on a side note my stock 4L60E is goin out, so in a few months I am goin to get that rebuilt a little bit more stout than stock. And I am looking at running a 2K stall converter. But my budget for the tranny does not include the budget for my motor. I have a separate budget for my tranny. I really appreciate the help.

[BR3W CITY]

Originally Posted by comicaltatertot

First question how is the "new" LT motors just an evolution of the LS? Is it due to a lot of things are the same except for like direct injection? I am just wonderin

I'd have to show you engineering drawings to have it make sense, but essentially they took a functional platform and made major changes to the induction, fuel, electronics. There are only a few small parts that actually retrofit (mostly bolts, seriously), but the block actually isn't all that different. The DI ports are a problem, but a TIG welder can fix that. There has already been discussion in some circles about doing so.

Its similar to the way the old LT1 shares some architecture with the SBC.

And I was looking for 300-350 wheel hp with a 2-2500K budget. Really looking for a good torque increase (well good for 5.3) If I can keep the heads/springs stock that would be great. If not I could send my heads to TEA get like a Stage 1 for 799 heads, then look at a Vinci Butt Kicker cam

Oh, well thats easy then. A cam and good tune will have you there, but I wouldn't keep stock springs with a new cam unless you like floating valves. A cam kit w/ springs, PR's, and locks is only $6-700, and you would't even have to pull the heads off to do it.

Oh and on a side note my stock 4L60E is goin out, so in a few months I am goin to get that rebuilt a little bit more stout than stock. And I am looking at running a 2K stall converter.

2k is so low it won't even be noticeable, and you won't gain and quickness from it. A looser convertor is gonna let you get more RPM and end up further in your tq/pwr band...which is going to make the truck feel much quicker. You don't need to go crazy, but a 28-3400 range stall will still be daily driveable.

bold

[BR3W CITY]

Originally Posted by Marv D

BR, am I understanding you that the aluminum 5.3 is the same as the LS1 block? Wait, that's not 'exactly' what your saying I know. But the 5.3 would accept the LS1 sleeve? then all thats left is the 4" stroke. Would the Aluminum 5.3 block tolerate that?

I've just gotten my feet wet in this LS world and am just smart enough to know,,, it's not the 'future'
it's the NOW.

Thats pretty much what I'm sayin in terms of the block. You can bore the existing sleeve to a certain point, or have the engine re-sleeved with the size you want in a "fresh" sleeve. I don't know if its "the ls1 sleeve" per-se, but you can get a 5.7l sleeve. The internal architecture will accept all those components, pistons, rods etc.

Its almost already the past again lol, although the new LT series motors aren't actually all new, they are the next half-evolution of the LS platform.

[tinydb84]

Maybe cost isnt a factor for you but I am on a budget and would get an LQ9 short block, cam it, and swap over everything else.

You'd have a better cam, decent heads, higher compression, and more cubes. If you work fast then your truck would only be down for the weekend.

[comicaltatertot]

Originally Posted by tinydb84

Maybe cost isnt a factor for you but I am on a budget and would get an LQ9 short block, cam it, and swap over everything else.

You'd have a better cam, decent heads, higher compression, and more cubes. If you work fast then your truck would only be down for the weekend.

Yeah I don't know if I can work that fast.....But I am still young and don't have a girlfriend and have a good paying job so.....I might just be able to make this work. Maybe even use this as an option for my '72 K/20 that I am tearing apart right now

[BR3W CITY]

The looser the convertor, the more slip it will allow before stalling (i.e stall convertor). Unfortunately that means more heat.

If towing is a real concern, then it changes the way I look at the setup just a bit, because your at a slight disadvantage in displacement. I'd be staying with a lower stall (more like the 18-2300 range you were considering), and a cam that makes as much tq as fast as possible, more like what many of the 4x4 and RV owners choose. Too much cam and stall with a trailer means you'll end up spending a lot of time slipping and out of the power band (inefficient power), wasting a ton of energy (fuel, heat).

If you really want to tow bigger stuff like v8 boats, skidsteers etc, then starting with a 6L becomes WAY more practical. The same amount of work (cam upgrade, stall, headers) in a 6.0 lets you run way more cam and still make gobs of torque. I literally have pulled stumps out with my truck on drag radials (I really wish I filmed that).

I officially have overused the (parenthesis) in this post.

[comicaltatertot]

Ok that sounds good, I figured as much (that is why I considered a 2K stall first) ok I will make sure the cam I choose makes torque fast (fast for a 5.3) Sometimes I wish I would have gone with a little bit heavier truck and just got the 6.0 would have been a little bit better than my 5.3. I just thought I would add in the parentheses of my own haha. Thanks again

[BR3W CITY]

Its all a give and take. I wouldn't be afraid to tow something with my high stall, if it was only once a year for a few miles.

short duration cams will probably be your best bet. A higher lsa won't chug quite as much in traffic, 115/116 probably adequate. It'll also help minimize surging which becomes very sketchy with a loaded trailer or in traffic.