When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Wrapping up a 428" LS7 based on a Gen IV 5.3L sleeved block.
LLSR Cam Motion, 265/283 @ .050" .720"/.710" 113lsa
13.8:1
BR7 heads ported by Frankenstein w/ Crower 1.8 shaft rockers
CID 4.5
1050 Dominator
Heading to the flywheel dyno soon....
Last edited by helicoil; Jan 18, 2023 at 11:38 AM.
Reason: 428", not a 430"
Wrapping up a 430" LS7 based on a Gen IV 5.3L sleeved block.
LLSR Cam Motion, 265/283 @ .050" .720"/.710" 113lsa
14:1
BR7 heads ported by Frankenstein w/ Crower 1.8 shaft rockers
CID 4.5
1050 Dominator
Heading to the flywheel dyno soon....
Just curious about pricing, and durability, vs dry sleeving an LS7 block. I'm thinking the price diff would be small. Assuming a Darton MID 5.3 block would be similar to LS7 dry sleeve block? Asking because I don't know which would be cheaper, or if they are actually comparable price wise. I wonder if there is an advantage durability wise going one way vs the other? Regardless, looks like a great, high power build......
MID sleeves aren’t really done anymore for LS platform. 5.3 are the cheapest, but have bad windage. LS2 is best for windage and strength unless you’re dry sumped or vacuum pump. Not sure of the specifics on the ls2 benefits but Steve at RED mentioned they were his favorite. Only reason to start with an ls7 block is if you have one already, or get a cheap one with cracked sleeves and you’re certain it’s a good core.
Just curious about pricing, and durability, vs dry sleeving an LS7 block. I'm thinking the price diff would be small. Assuming a Darton MID 5.3 block would be similar to LS7 dry sleeve block? Asking because I don't know which would be cheaper, or if they are actually comparable price wise. I wonder if there is an advantage durability wise going one way vs the other? Regardless, looks like a great, high power build......
For what this is capable of making, the 5.3L is plenty good enough and a light alternative to an a/m iron block. Most all aftermarket 4" cranks have gun-drilled mains like a factory LS2/3 crank. Bay to bay breathing doesn't seem too bad for what a 4" crank engine normally produces compared to one with an early non-drilled crank. I wouldn't hesitate to do a 5.3L sleeve build for any NA effort. I wouldn't sacrifice a nice LS2 to sleeve unless the bores were beyond use, those blocks are getting harder to find in nice condition and are plenty strong for most boosted street/strip builds (they are light too!).
Nice looking setup, interested in how it stacks up against last years 430" with the f710's.
I will know in a couple of weeks. This doesn't have the aggressive camshaft/valvetrain that one did due to these heads being built for a hydraulic roller to start with. I converted them to a solid valvetrain. The BR7's don't have the BS 'big spring' pockets limiting the cam selection I could go with. The shaft rocker set up uses the smaller 8mm stand bolts, so the 1238X springs are about the limit, limiting the lobe lift. This one also has steel valves, but the port work is pretty nice. They have 282cc intake ports. 2.250" intake valves, 1.610" exh valves. Advertised flow numbers are strong everywhere.
I will know in a couple of weeks. This doesn't have the aggressive camshaft/valvetrain that one did due to these heads being built for a hydraulic roller to start with. I converted them to a solid valvetrain. The BR7's don't have the BS 'big spring' pockets limiting the cam selection I could go with. The shaft rocker set up uses the smaller 8mm stand bolts, so the 1238X springs are about the limit, limiting the lobe lift. This one also has steel valves, but the port work is pretty nice. They have 282cc intake ports. 2.250" intake valves, 1.610" exh valves. Advertised flow numbers are strong everywhere.
Either way it will be interesting, the br7 is a great casting, i wont be surprised if it makes similiar power. I'm wishing I would have gone with more duration like whats in the cam in this motor. I went with 256/268 on a 110 lsa and itmakes insane torque, been on the bumper 5 or 6 times this year.
I just did Brodix BR7 (ported by Advanced Induction in NC) build cam (I would say a mid-level street cam) was a HR 246/258 650 lift 114 lsa, 12 to 1 compression (made for pump gas 93), 455 CID and it made 757 hp at 6,700 and tq was 665 at 5,000 rpm, with a ported Mamo MSD intake, 1 7/8 headers. The heads were 280 cc with a 2.20 / 1.61 valves with PAC 1207 springs 150#/430# and OEM rockers with bearing upgrade. Flow on heads was 314 @ 400, 378 @ 600 and 393 @ 800 exhaust with a tube was around 270 @ 700.
I just did Brodix BR7 (ported by Advanced Induction in NC) build cam (I would say a mid-level street cam) was a HR 246/258 650 lift 114 lsa, 12 to 1 compression (made for pump gas 93), 455 CID and it made 757 hp at 6,700 and tq was 665 at 5,000 rpm, with a ported Mamo MSD intake, 1 7/8 headers. The heads were 280 cc with a 2.20 / 1.61 valves with PAC 1207 springs 150#/430# and OEM rockers with bearing upgrade. Flow on heads was 314 @ 400, 378 @ 600 and 393 @ 800 exhaust with a tube was around 270 @ 700.
Either way it will be interesting, the br7 is a great casting, i wont be surprised if it makes similiar power. I'm wishing I would have gone with more duration like whats in the cam in this motor. I went with 256/268 on a 110 lsa and itmakes insane torque, been on the bumper 5 or 6 times this year.
I sent Thompson the 5.3 and had them sleeve it, deck it, align hone it and dowel the mains.
Help me understand this, please. How can you get a 4.125" bore on a 5.3 block without going MID? I honestly though MID only. Can you dry sleeve the 5.3 to 4.125"? I know Im missing something (knowledge!!).....
Help me understand this, please. How can you get a 4.125" bore on a 5.3 block without going MID? I honestly though MID only. Can you dry sleeve the 5.3 to 4.125"? I know Im missing something (knowledge!!).....
only the ls6 block and maybe early ls1 blocks can be mid sleeve. all others can be dry sleeved
Help me understand this, please. How can you get a 4.125" bore on a 5.3 block without going MID? I honestly though MID only. Can you dry sleeve the 5.3 to 4.125"? I know Im missing something (knowledge!!).....
Yessir. The 5.3 (gen4) block can be dry sleeved and can be taken out to 4.200 if wanted. 4.185 is recommended max N/A bore and 4.155 max bore with bewst. Darton sleeves of course. The MID stuff was hot back when you had yours done Mike, but I don’t think it’s even available anymore. I was told that Darton stopped making the MID sleeves. Dry sleeves are the norm nowadays. Far easier to install, and almost zero chance of coolant leaks. Gen4 blocks only.
Yessir. The 5.3 (gen4) block can be dry sleeved and can be taken out to 4.200 if wanted. 4.185 is recommended max N/A bore and 4.155 max bore with bewst. Darton sleeves of course. The MID stuff was hot back when you had yours done Mike, but I don’t think it’s even available anymore. I was told that Darton stopped making the MID sleeves. Dry sleeves are the norm nowadays. Far easier to install, and almost zero chance of coolant leaks. Gen4 blocks only.
That's great!! So, if I'm understanding correctly, both aluminum and iron blocks can go to a 4.200 bore w/dry sleeves? Don't mean to hijack, but this is useful to most here who dont know for sure.....
That's great!! So, if I'm understanding correctly, both aluminum and iron blocks can go to a 4.200 bore w/dry sleeves? Don't mean to hijack, but this is useful to most here who dont know for sure.....
Im not so sure about the iron blocks. They can take a repair sleeve, but can’t be dry sleeved in the same manner that the aluminum blocks can. They aren’t siamesed bore like the aluminum blocks, so there’s not enough meat at the cylinders to handle an oversized sleeve.
7 Most Reliable High-Performance Engines GM Has Ever Built
Slideshow:These GM engines didn't just make huge power, they survived abuse, boost, track days, and six-digit mileage with a reputation for refusing to quit.
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.
430" ls7 
