5.3 build- boring and compression ratio input
Thread Starter
Teching In
Joined: Jul 2017
Posts: 12
Likes: 0
5.3 build- boring and compression ratio input I've got my 5.3 build list pretty much nailed down which is all thanks to my last thread. I dropped my Gen 3 block and crank off at the machine shop a couple weeks ago to get cleaned up and inspected. I received a call today and was told that the crank is good, but needs a polish. The block on the other hand would need to be at least bored .010 over.
So, now this effects my planned build. I was going to do: stock 5.3 bore block, 4.8 pistons, 799 heads milled down .030 to achieve 10.5:1 compression. I was also going to run a TSP 224r 112 Lsa cam.
The machine shop is wanting around $250 to bore it and I've found a brand spanking new 5.3 block off Sunmitracing for $350. Should I just buy a new stock block and carry on with my build as planned?
OR since I need to bore my current block over should I just go ahead and bore it out to a 5.7? If I do that I'll need a new cam choice I suppose along with the obvious balancing of the rotating assembly.
My 799 heads have not been milled down yet, but would boring the block out affect my compression ratio? It's not effecting the combustion chamber much so I wouldn't think it would, but I'm not sure.
Any input is helpful, I'm kind of leaning towards just carrying out my build as initially planned since it sounds a little cheaper to me.
So, now this effects my planned build. I was going to do: stock 5.3 bore block, 4.8 pistons, 799 heads milled down .030 to achieve 10.5:1 compression. I was also going to run a TSP 224r 112 Lsa cam.
The machine shop is wanting around $250 to bore it and I've found a brand spanking new 5.3 block off Sunmitracing for $350. Should I just buy a new stock block and carry on with my build as planned?
OR since I need to bore my current block over should I just go ahead and bore it out to a 5.7? If I do that I'll need a new cam choice I suppose along with the obvious balancing of the rotating assembly.
My 799 heads have not been milled down yet, but would boring the block out affect my compression ratio? It's not effecting the combustion chamber much so I wouldn't think it would, but I'm not sure.
Any input is helpful, I'm kind of leaning towards just carrying out my build as initially planned since it sounds a little cheaper to me.
For only .010", your machine shop is only going to hone it out. You could probably get .010" larger hypereutectic pistons from WS6Store and get it assembled like that. This would be the best bang for the buck option IMO.
If you want to use LS1 pistons, your machinist would have to bore and hone the block, which is going to be more expensive. You might be able to find some used pistons in the classifieds, but you'll be taking a chance since they would all be 10+ years old. Again, you could probably get hypereutectic pistons as well. This option would make significantly more power than a 5.3 due to the larger displacement and bore size. It's more expensive, but there's more reward.
If you want to use LS1 pistons, your machinist would have to bore and hone the block, which is going to be more expensive. You might be able to find some used pistons in the classifieds, but you'll be taking a chance since they would all be 10+ years old. Again, you could probably get hypereutectic pistons as well. This option would make significantly more power than a 5.3 due to the larger displacement and bore size. It's more expensive, but there's more reward.
Gen-iii 5.3 al ? Hi C10, there are TWO choices for a GEN-III (AL?) block.
The early has TWO long head bolt sizes = NOT OK
The early has a 1" HOLE between the Main/Cam bulkheads = NOT OK
The early has NO provision for the Chain Guide = NOT OK
ANSWER these questions FIRST.
The GEN-IV AL is fine with THICK WALLS and MUCH Stronger.
The next step before a "bore" is to Sonic AFTER RINGS ARE FOUND.
YOUR shop 3.78+.010 ???? RINGS ??????
Total Seal 3.78+.005 OK
Lance
The early has TWO long head bolt sizes = NOT OK
The early has a 1" HOLE between the Main/Cam bulkheads = NOT OK
The early has NO provision for the Chain Guide = NOT OK
ANSWER these questions FIRST.
The GEN-IV AL is fine with THICK WALLS and MUCH Stronger.
The next step before a "bore" is to Sonic AFTER RINGS ARE FOUND.
YOUR shop 3.78+.010 ???? RINGS ??????
Total Seal 3.78+.005 OK
Lance
Thread Starter
Teching In
Joined: Jul 2017
Posts: 12
Likes: 0
My block is an Iron block gen 3 5.3
Will punching it out to take 5.7 pistons affect my compression ratio? As stated before I already have a set of 799 heads that I was going to have milled down to get my goal of 10.5:1 compression.
I already know I'll need to get the rotating assembly balanced.
Would my cam choices open up to the same choices the LS1 guys have? I seem pretty limited right now with the 5.3, that's why I was going to do a 224R
Will punching it out to take 5.7 pistons affect my compression ratio? As stated before I already have a set of 799 heads that I was going to have milled down to get my goal of 10.5:1 compression.
I already know I'll need to get the rotating assembly balanced.
Would my cam choices open up to the same choices the LS1 guys have? I seem pretty limited right now with the 5.3, that's why I was going to do a 224R
http://www.wallaceracing.com/cr_test2.php
You could use more duration and overlap since you will have more displacement and you won't have to mill as much to achieve your desired compression ratio so you'll gain PTV. You will be able to better unshroud the valves with the larger bore as well.
Thread Starter
Teching In
Joined: Jul 2017
Posts: 12
Likes: 0
Alright, I think I've got it figured out.
If I bore my 5.3 to a 5.7 and run stock 799/243's then essentially I'll have an Iron LS6 that would be at 10.5:1 compression.
Then I'd pop a 228R cam in and be all set.
Sounds simple enough.
If I bore my 5.3 to a 5.7 and run stock 799/243's then essentially I'll have an Iron LS6 that would be at 10.5:1 compression.
Then I'd pop a 228R cam in and be all set.
Sounds simple enough.
Trending Topics
If I was going to go with 5.3 I'd ditch the iron and go 4 th gen AL and run std , with its flat tops and floating pin rods. If you want to go 5.7 , with this block....... it can go 3.905+. if you Sonic check it up to 3.920. Bonus it already has 243/799 heads also
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo Thread Starter
Teching In
Joined: Jul 2017
Posts: 12
Likes: 0
I'm just going to stick with what I got. Bore it out 3mm over and put LS1 pistons in it, balance the rotating assembly, run the 799 heads without milling them and I'll be at my goal of 10.5:1 cr. Then I think I'm going to do the TSP 228R cam
Thanks for the mention KCS. We have lots of pistons avail but for a "badass build" the 5.7l iron is it.
If its going into a truck, dont do the 228r. use something smaller. unless you get it cheap. std pattern cams arent as well performing as splits.
Using the 228r in a truck isnt very good unless you supplement the bottom end with 373+ gears and a 3k+ stall.
A smaller and split cam would fit you better. id look at the 223 226 tsp stg4 truck cam
If its going into a truck, dont do the 228r. use something smaller. unless you get it cheap. std pattern cams arent as well performing as splits.
Using the 228r in a truck isnt very good unless you supplement the bottom end with 373+ gears and a 3k+ stall.
A smaller and split cam would fit you better. id look at the 223 226 tsp stg4 truck cam
Thread Starter
Teching In
Joined: Jul 2017
Posts: 12
Likes: 0
Thanks for the mention KCS. We have lots of pistons avail but for a "badass build" the 5.7l iron is it.
If its going into a truck, dont do the 228r. use something smaller. unless you get it cheap. std pattern cams arent as well performing as splits.
Using the 228r in a truck isnt very good unless you supplement the bottom end with 373+ gears and a 3k+ stall.
A smaller and split cam would fit you better. id look at the 223 226 tsp stg4 truck cam
If its going into a truck, dont do the 228r. use something smaller. unless you get it cheap. std pattern cams arent as well performing as splits.
Using the 228r in a truck isnt very good unless you supplement the bottom end with 373+ gears and a 3k+ stall.
A smaller and split cam would fit you better. id look at the 223 226 tsp stg4 truck cam
I'll basically be building an iron LS6, just curious as to why I'd have to run such a small cam?
TECH Senior Member
Joined: Jun 2016
Posts: 22,291
Likes: 3,616
From: Central Cal.
To give you enough starting torque for a heavier vehicle. Being a pickup, I would bet it weighs closer to a bit over 4k#. A milder cam would make driving it less stressful with less bucking, etc.
Thread Starter
Teching In
Joined: Jul 2017
Posts: 12
Likes: 0
