New 5.3L Build Questions
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New 5.3L Build Questions I'm starting a new build from scratch and ordering a 5.3 block from Summit.
My goals is a naturally aspirated street motor for a 3rd Gen F-Body with a T56 and 3.73 gears.
I'm building the short block to stock specs but plan on modifications in 3 areas. Intake, heads, and cam.
To keep the costs down I'm looking at used GM LS parts for intake and heads. The cam I would get new. Looking to stay under $2000 for these items.
Intake (used) - LS6
Heads (used) - 243/799
Cam (new) - So many options available I need some help. Using stock lifters and 1.7 rockers (will install trunion upgrade). Would consider new dual springs if need be.
If there are better used GM or aftermarket options for intakes and heads comments are appreciated.
My goals is a naturally aspirated street motor for a 3rd Gen F-Body with a T56 and 3.73 gears.
I'm building the short block to stock specs but plan on modifications in 3 areas. Intake, heads, and cam.
To keep the costs down I'm looking at used GM LS parts for intake and heads. The cam I would get new. Looking to stay under $2000 for these items.
Intake (used) - LS6
Heads (used) - 243/799
Cam (new) - So many options available I need some help. Using stock lifters and 1.7 rockers (will install trunion upgrade). Would consider new dual springs if need be.
If there are better used GM or aftermarket options for intakes and heads comments are appreciated.
Last edited by JohnNJ; Sep 5, 2017 at 08:06 AM.
You could use 4.8 pistons to bump up compression with 243 heads. Then an ls6 intake with longtubes. Not sure on cam.
id personally go with bigger cubes if I was staying N/A. Maybe punch it out or find the motor and trans out of a wrecked camaro or firebird and get the harness too. Starting from scratch is hard. coils, injectors, etc add up quick and will nickel and dime you. It would be best to find a pull out motor with harness etc to make it easy. It will save you $$ in the long run.
id personally go with bigger cubes if I was staying N/A. Maybe punch it out or find the motor and trans out of a wrecked camaro or firebird and get the harness too. Starting from scratch is hard. coils, injectors, etc add up quick and will nickel and dime you. It would be best to find a pull out motor with harness etc to make it easy. It will save you $$ in the long run.
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To build on moekluse's post: Go ahead with the block, but also get a junkyard motor as he said and put all the stuff from the JY motor on the newly built shortblock. That way you have a fresh shortblock AND ALL the stuff to throw on and around it. Just an idea...
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Thanks for the comments and tip about the 4.8 pistons. I'm not considering a stroker crank at this point due to cost. So it's a stock reman for now.
I've considered a used core but the majority of parts like the rotating assembly, intake, heads, oil pan, gaskets, sensors, flexplate etc will not be used. So I don't know if $700-800 expense will be worth it for the parts I would actually use.
Which company is Pat G with?
I've considered a used core but the majority of parts like the rotating assembly, intake, heads, oil pan, gaskets, sensors, flexplate etc will not be used. So I don't know if $700-800 expense will be worth it for the parts I would actually use.
Which company is Pat G with?
like I said above, it adds up quick! It would be best to find an already running pull out motor with harness and tranny
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If I was going NA I wouldn't consider engines below 5.7L and nothing made of IRON.
NA power relies on lightweight, and large displacement. Take everything out of the car. Use lightweight body panels. Low resistance tires, and the lightest wheels you can find. Prioritize the wheels being lightweight forging. The pro of this kind of build is maximum fuel economy. It should be 6-speed and weight 3200lbs or less (preferably 2800lbs).
NA power relies on lightweight, and large displacement. Take everything out of the car. Use lightweight body panels. Low resistance tires, and the lightest wheels you can find. Prioritize the wheels being lightweight forging. The pro of this kind of build is maximum fuel economy. It should be 6-speed and weight 3200lbs or less (preferably 2800lbs).
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If I was going NA I wouldn't consider engines below 5.7L and nothing made of IRON.
NA power relies on lightweight, and large displacement. Take everything out of the car. Use lightweight body panels. Low resistance tires, and the lightest wheels you can find. Prioritize the wheels being lightweight forging. The pro of this kind of build is maximum fuel economy. It should be 6-speed and weight 3200lbs or less (preferably 2800lbs).
NA power relies on lightweight, and large displacement. Take everything out of the car. Use lightweight body panels. Low resistance tires, and the lightest wheels you can find. Prioritize the wheels being lightweight forging. The pro of this kind of build is maximum fuel economy. It should be 6-speed and weight 3200lbs or less (preferably 2800lbs).
OK wait a minute. Carbon fiber hood and lightweight wheels great for the street. I am not suggesting stripping it completely, when I say "everything" it is within a good taste i.e. take out the spare change, spare tire maybe, the candy stuck to the carpet, remove the ant farm, the goo in the corners of the trunk, wash and clean that thing spotless. And maybe take out the rear seats or something if you can afford to.
Don't mean to take everything literally when I post it "everything" to me is like "anything you can live without"
And yes I would lightweight wheels (if they are significantly lighter) > cam/head/intake
due mainly for the wide variety of effects they will have (more economy, more power, better handling and braking, it basically improves everything about the car)
because the wheels you can keep with the car, they also fit the next same car, and you can always re-sell them. If they are significantly lighter? yes it will make a huge difference.
And finally, this I only suggested because I wanted to make the owner AWARE Of these things. No, don't prioritize wheels right now, that is just ridiculous. Even I've never purchased a new set of wheels. What a waste of $$$. But as long as we are AWARE of the positive influence a nice lightweight set of XXXX will have, we can make informed decisions about other things too (because now "I" see how important weight and rotating weight is...) I can think critically about the future of the car in terms of performance and economy.
Don't mean to take everything literally when I post it "everything" to me is like "anything you can live without"
And yes I would lightweight wheels (if they are significantly lighter) > cam/head/intake
due mainly for the wide variety of effects they will have (more economy, more power, better handling and braking, it basically improves everything about the car)
because the wheels you can keep with the car, they also fit the next same car, and you can always re-sell them. If they are significantly lighter? yes it will make a huge difference.
And finally, this I only suggested because I wanted to make the owner AWARE Of these things. No, don't prioritize wheels right now, that is just ridiculous. Even I've never purchased a new set of wheels. What a waste of $$$. But as long as we are AWARE of the positive influence a nice lightweight set of XXXX will have, we can make informed decisions about other things too (because now "I" see how important weight and rotating weight is...) I can think critically about the future of the car in terms of performance and economy.
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From: Central Cal.
"Significantly lighter" wheels (like Fikse, Forgeline, etc.) can run $3-4000 a set. You forget this guy is ON A BUDGET. Nowhere did he say he is looking for max fuel economy. That is a tangent you went out on. The OP just wants to build a decent engine to go fast with and have some fun. THAT'S IT. Carbon fiber?? Budget?? RIGHT!! Stay on track, Talon.
Hmm well he said "buying a bare block" so I immediately assume he was a masochist and tried to make the best of the situation (still spending gobs of money- but at least he can't assemble wheels wrong and wind up trashing them full of metal pieces within 50 miles) i.e. 5k into a trash block or 5k into wheels which one goes farther.
budget = max fuel economy.... so yeah still king correctness ;X I am starting to love you though.
budget = max fuel economy.... so yeah still king correctness ;X I am starting to love you though.
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From: Central Cal.
Budget does NOT always = fuel economy. It limits spending on a project. You're doing the same **** you always do, justifying statements with semantics. Quit NOW, while you're not too far behind. AND, your brand of sarcasm gets weaker all the time.
Guys... this is an engine forum. If you wanna fight, go argue with mustang fanboys on YouTube comments. Let's just help the OP do a budget Ls swap.
since your on a tight budget, go with the 5.3, find a pullout. You can't use the harness with it though, it was designed for autos. Find a cheap t56 off eBay or this forum in the classifieds
2000 bucks for 243 heads and ls6 intake should be doable. As far as drive train:
motor- at least 500 bucks for a good running motor
trans-1500 to 2000
miscellaneous- a **** ton.
I'm telling you, it's so much easier and cheaper to find a pull out. Even if you go with summit block, it will require machine work.
since your on a tight budget, go with the 5.3, find a pullout. You can't use the harness with it though, it was designed for autos. Find a cheap t56 off eBay or this forum in the classifieds
2000 bucks for 243 heads and ls6 intake should be doable. As far as drive train:
motor- at least 500 bucks for a good running motor
trans-1500 to 2000
miscellaneous- a **** ton.
I'm telling you, it's so much easier and cheaper to find a pull out. Even if you go with summit block, it will require machine work.
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Wow, busy thread while I was away. 
I appreciate the wisdom of the collective.
My intent for starting with a bare block was not just to save money but to take my time and enjoy scrounging for parts. I'm in no hurry and part of the enjoyment for me is getting each new piece.
But I do see a couple of points here. For a NA motor, displacement is your friend and I'm going to check prices for a used LQ4 today at a couple of local yards.
Also is "Pat G" Patrick Guerra? I think I found his web site.
I appreciate the wisdom of the collective.
My intent for starting with a bare block was not just to save money but to take my time and enjoy scrounging for parts. I'm in no hurry and part of the enjoyment for me is getting each new piece.
But I do see a couple of points here. For a NA motor, displacement is your friend and I'm going to check prices for a used LQ4 today at a couple of local yards.
Also is "Pat G" Patrick Guerra? I think I found his web site.
Wow, busy thread while I was away.
I appreciate the wisdom of the collective.
My intent for starting with a bare block was not just to save money but to take my time and enjoy scrounging for parts. I'm in no hurry and part of the enjoyment for me is getting each new piece.
But I do see a couple of points here. For a NA motor, displacement is your friend and I'm going to check prices for a used LQ4 today at a couple of local yards.
Also is "Pat G" Patrick Guerra? I think I found his web site.
I appreciate the wisdom of the collective.
My intent for starting with a bare block was not just to save money but to take my time and enjoy scrounging for parts. I'm in no hurry and part of the enjoyment for me is getting each new piece.
But I do see a couple of points here. For a NA motor, displacement is your friend and I'm going to check prices for a used LQ4 today at a couple of local yards.
Also is "Pat G" Patrick Guerra? I think I found his web site.
I'm doing my own personal car, 1978 trans am ws6 and I thought i could do it for 20k
That turned into a complete restoration and 80,000 dollars later, the car is still no where close to being done.
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So I checked some local yards and found a LQ4 motor from a recently scrapped 2004 Silverado with ~ 100K miles. The vehicle had light front driver side damage and didn't even deploy the airbags so all looks promising. I'm going to move forward and pick it up next week.
It has the harness and I've read some threads here about converting it over for a T56.
Thanks for the input all.
It has the harness and I've read some threads here about converting it over for a T56.
Thanks for the input all.