For a semi-budget turbo 5.3 liter LSx build are (CNC) ported heads worth the expense?

B'klyn9C1

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Mar 17, 2013
What I mean by "semi-budget" is that I willing to buy a high mile junk yard 5.3 liter aluminum block LSx like a L33 but instead of just plopping it into my car with just a change of ARP head bolts and valvesprings. I want to give it a good rebuilding with a machined crank, upgrade to good stock Gen IV rods like out of a LS3/L92, fresh bearings and rings, fully balanced rotating assembly and ARP fasteners everywhere.

My power goal is 600 to 700 RWHP in a daily driven 1995 Chevy Caprice 9C1.

There are two schools of thought regarding making big power on turbo setups especially on budget builds. They are the "the foundation of ANY big power setup is set of good flowing heads" and other is "don't bother porting the heads just let the boost do the work".

Bottomline: Are ported stock 799/243 heads or even aftermarket TFS's or AFR's worth the expense on such a build or shall just forget about it apply the money elsewhere and turn up the boost an extra 1 or 2 psi??? Or can you guys here provide me a middle ground solution between those two schools of thought??????
 
Back to the topic at hand...
I'd stick w/ the "good foundation" idea.
I'd take the $$ that the stock rods/bolts/rebuild will cost, and get a set of aftermkt rods.
Head studs, not bolts.
Heads... A set of good flowing heads w/ the cam, [Tick has some good grinds], to match will allow your 6-700RW to be attained at lower boost, thus somewhat less heat...Always a winner. [A cleaned up set of 317's would work]
Lastly, being it's a DD, I'd not spend the additional $$ on an alum block...A good old cast block will do just fine.....For a lot less money.;)

I'm sure some will agree, some not. This is the way my ragged out T Type is going together..........:D
 
I have a new fully machined LQ9 6.0 block with studded mains stock crank and some kick a$@ AllPro heads that would make awesome starting point for your project.
 
my badddddd just making sure moderators are on there feet ;)

No offense taken!,

Considering that the Turbo Buick 3.8 Liter was the only mass produced OEM EFI GM turbo engine in recent years. I think I came to the right place. Besides the guy I am looking to do my turbo LSx conversion is one of the biggest GN guru in the NYC area and It was a GN owner who persuaded me to go the turbo route. There is something appealing about 700 RWHP along with good street manners and good gas mileage.
 
Back to the topic at hand...
I'd stick w/ the "good foundation" idea.
I'd take the $$ that the stock rods/bolts/rebuild will cost, and get a set of aftermkt rods.
Head studs, not bolts.
Heads... A set of good flowing heads w/ the cam, [Tick has some good grinds], to match will allow your 6-700RW to be attained at lower boost, thus somewhat less heat...Always a winner. [A cleaned up set of 317's would work]
Lastly, being it's a DD, I'd not spend the additional $$ on an alum block...A good old cast block will do just fine.....For a lot less money.;)

I'm sure some will agree, some not. This is the way my ragged out T Type is going together..........:D

The reason for going for the aluminum block is that I want to autocross and road raced the car and so I want save some weight off the the frontend. Besides from talking with engine builders the iron block LS series engines weigh more than even the Gen I and Gen II SBC's. Long deep skirt and all, etc.. From what I have been told the 4.8 and the 5.3 liter aluminum LS motor have the thickest iron cylinder liners and OEM pistons of the series. So along with the small(est) bore making them arguably the most boost friendly of the series.

The 6.0 liter, esp. the 6.2 liter L92's are way more expensive and not as plentiful. The L92 heads flow stupid amount of air as cast (300 CFM's) their decks are kind of thin for high boost situations. Though the LSA heads can be had new for $200 each but bare.
 
" is that I want to autocross and road raced the car"...
Sorry, I didn't see that in your first post.
 
I have a set of 243s stage 1 ported by patriot. They would be great for this 5.3 build. You should look into ls1tech.com there is tons of information over there. I would go with a set of forged rods. I just picked up a set of k1 rods for 420 bones from excessive motorsports
 
theres also a cheaper option of porting them yourself , theres a guy on you tube that has done a very thorough video series on porting ls heads AGearHead4Life is his you tube user name , make sure to capitalize like I did
 
Get a stock L33. Head studs, LS9 head gaskets, LS6 intake, good springs and a small cam. Slap a TC78 on there and you won't need much else. It'll live a long happy life on the stock short block. If you question that at all go over to ls1tech and look up Skinnies RX7 that went I think 8.60s many many many times and set the world stock short block record. He is a good friend and I have watched him abuse the crap out of those L33s for years. I personally am doing the same thing but with an iron block. It is cheap enough for me to buy 5.3s that I probably wont ever fix one. Just swap em out.
 
I agree with the cleaned up 317s, that's what I'm running. Was about $1100 locally but it was all the bells and whistles. I figured since I only paid $400 for the motor, the heads were free, I'd be an ahole not to spend the money lol.
 
What I mean by "semi-budget" is that I willing to buy a high mile junk yard 5.3 liter aluminum block LSx like a L33 but instead of just plopping it into my car with just a change of ARP head bolts and valvesprings. I want to give it a good rebuilding with a machined crank, upgrade to good stock Gen IV rods like out of a LS3/L92, fresh bearings and rings, fully balanced rotating assembly and ARP fasteners everywhere.

My power goal is 600 to 700 RWHP in a daily driven 1995 Chevy Caprice 9C1.

There are two schools of thought regarding making big power on turbo setups especially on budget builds. They are the "the foundation of ANY big power setup is set of good flowing heads" and other is "don't bother porting the heads just let the boost do the work".

Bottomline: Are ported stock 799/243 heads or even aftermarket TFS's or AFR's worth the expense on such a build or shall just forget about it apply the money elsewhere and turn up the boost an extra 1 or 2 psi??? Or can you guys here provide me a middle ground solution between those two schools of thought??????

I'm pretty darn sure the L33's came with the larger rods and floating pistons already. They were among the first motors to get them. They also came with the great 243 heads and a cam very similar to the LS6. Honestly a set of $60 Ebay studs, decent ML gaskets (ls1/ls9) and som $60 valve springs are all you need for your power goals. You don't need to do a damn thing to the motor. ARP fastners are a total waste of money and you can't re-size the OEM rods anyway. (you need to do this to run ARP rodbolts properly).

OEM hardware everywhere (except heads studs) has been proven to run well into the 1000 crank HP range. You don't even need to change the cam to hit your 600WHP goal easily. Don't over complicate or over spend. Ported or aftermarket heads are not needed until you hit the 900+whp ranges.

I went 8's in the 1/4 and made over 800 to the wheels with a $220 JY 160k 5.3. All OEM hardware on an the older "weak" rods and pistons. With untouched 317 casting heads (8.6:1 compression) and the small S475 turbo. (1.10 t4, 74mm exh wheel) I ran a $98 GM zr1 cam with cheap pac1218 springs. Also had two random piston rod assys from another motor in it.

I would suggest you buy a decent timing set as I believe that is what eventually killed my setup.

Good luck!
 
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I agree with the cleaned up 317s, that's what I'm running. Was about $1100 locally but it was all the bells and whistles. I figured since I only paid $400 for the motor, the heads were free, I'd be an ahole not to spend the money lol.
Hey forcefed86 what are you using for computer are you using a fast system or stock GM computer?
 
Just thought I'd share this here with you. This is a 160k mile junkyard lq4. Edelbrock intake, custom grind cam and ARP bolts, that is it, legitimately a stock junkyard build. This run is on 21psi and made 707rwhp, on a Mustang Dyno. This setup has 10k+ miles on it, and that's 10k HARD miles, countless pulls at 23psi and a 75 shot, and never a single issue. Turbo is a billet s480. Stock ecu tuned with HP Tuners.

Just some food for thought

 
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