Ls-3(A) 418/429 ideas
Ls-3(A) 418/429 ideas Well planning on having an ls3 or LSA block into a 418 or 429.
I keep hearing if I want a 429 go with an LSA block and 418 go to an ls3 block. I'm thinking 12.5:1 on pump gas (93) please correct me if I can or can not run it. I would really like to run my B.E.S. L99 heads that are also milled 0.040. I'm planning on running a LL solid roller VVT cam with this combo. My current L99 setup (VVT) is doing wonders at 521rwhp 478rwtq on pump gas. People say it seems high but my fif gen runs 10.73 on motor. My goal is to push this car down the 1/4 into the 9.90s N/A but want and need the extra power and TQ. Please be easy on me since it's my 1st engine build that I want part in vs having someone just build it without knowing what I got. So why is it a 429 won't live as long? Hope I'm asking right. This will be backed up with a 6L80E so idk if that helps on ideas.
Thanks.
I keep hearing if I want a 429 go with an LSA block and 418 go to an ls3 block. I'm thinking 12.5:1 on pump gas (93) please correct me if I can or can not run it. I would really like to run my B.E.S. L99 heads that are also milled 0.040. I'm planning on running a LL solid roller VVT cam with this combo. My current L99 setup (VVT) is doing wonders at 521rwhp 478rwtq on pump gas. People say it seems high but my fif gen runs 10.73 on motor. My goal is to push this car down the 1/4 into the 9.90s N/A but want and need the extra power and TQ. Please be easy on me since it's my 1st engine build that I want part in vs having someone just build it without knowing what I got. So why is it a 429 won't live as long? Hope I'm asking right. This will be backed up with a 6L80E so idk if that helps on ideas.
Thanks.
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From: Mississippi
The reason the 429 wouldn't last as long cause of the stroke that'll be required. If your bore is 4.070 you would need a 4.125 stroker crank to reach a 429ci motor.
The problem is the more stroke you run the more that piston comes out the bottom of sleeve giving that piston more of a rocking effect and it's harder to control oil with larger cranks to. That especially happens to guys wanting to run large cranks in factory blocks. Truth is the sleeves isn't long enough as they are is a aftermarket block....
Most aftermarket blocks have a longer sleeve therefore you can get a away with a larger crank and still keeping those pistons in the bore nicely.
The problem is the more stroke you run the more that piston comes out the bottom of sleeve giving that piston more of a rocking effect and it's harder to control oil with larger cranks to. That especially happens to guys wanting to run large cranks in factory blocks. Truth is the sleeves isn't long enough as they are is a aftermarket block....
Most aftermarket blocks have a longer sleeve therefore you can get a away with a larger crank and still keeping those pistons in the bore nicely.
Launching!
Joined: Dec 2014
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From: Leesburg, Virginia
Man, if people think your numbers are high with times like that, they're crazy. I agree with the above as well. If you were sleeving the block, I wouldn't be worried about it, but if you were staying stock sleeve I wouldn't go over a 416/418.
93 octane will be fine for 12.5:1
93 octane will be fine for 12.5:1
The reason the 429 wouldn't last as long cause of the stroke that'll be required. If your bore is 4.070 you would need a 4.125 stroker crank to reach a 429ci motor.
The problem is the more stroke you run the more that piston comes out the bottom of sleeve giving that piston more of a rocking effect and it's harder to control oil with larger cranks to. That especially happens to guys wanting to run large cranks in factory blocks. Truth is the sleeves isn't long enough as they are is a aftermarket block....
Most aftermarket blocks have a longer sleeve therefore you can get a away with a larger crank and still keeping those pistons in the bore nicely.
The problem is the more stroke you run the more that piston comes out the bottom of sleeve giving that piston more of a rocking effect and it's harder to control oil with larger cranks to. That especially happens to guys wanting to run large cranks in factory blocks. Truth is the sleeves isn't long enough as they are is a aftermarket block....
Most aftermarket blocks have a longer sleeve therefore you can get a away with a larger crank and still keeping those pistons in the bore nicely.
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From: Studewood/Acres-Homes TX.
Well the 4.100-4.125 stroke will work as KCS said but piston choice is critical. It just seems to present major problems with the Is 1,2 and LQ9 blocks but can be corrected with the Correct piston choice. But most engine builders would generally recommend staying @ 4 inch stroke with stock sleeve blocks. Presents less problems. Aka: lot easier on pistons.
But to the question of running 93 octane with 12.5 compression ratio.......You will need a Donkey Dick cam to bleed off the cylinder pressure. Martin recommended no more than 12.0 with a cam in the 256 range with my 408, your wanting more stroke so I would think you would need a cam with at least upper 260 range in duration.. More than not: in the 270 range to run 12:5 comp. with that much stroke. I run a solid roller in my case so, 256 would be like 252-250 @ .050 with a Hydraulic roller. So mid to upper 260 range if not more.
You could always run Corn or Race fuel if it's a track only car.
But to the question of running 93 octane with 12.5 compression ratio.......You will need a Donkey Dick cam to bleed off the cylinder pressure. Martin recommended no more than 12.0 with a cam in the 256 range with my 408, your wanting more stroke so I would think you would need a cam with at least upper 260 range in duration.. More than not: in the 270 range to run 12:5 comp. with that much stroke. I run a solid roller in my case so, 256 would be like 252-250 @ .050 with a Hydraulic roller. So mid to upper 260 range if not more.
You could always run Corn or Race fuel if it's a track only car.
Last edited by lil john; Mar 31, 2015 at 06:17 PM.
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From: Studewood/Acres-Homes TX.
Well let's see.
1st off is the LSA block is stronger, piston oil coolers....etc and all but, check out the $ difference in blocks.
You have heads. $o rockers, lifter(all other top end parts) could be gotten on the premise of running a solid roller.
But off the head numbers could be as low as 650 but as high as 800 depending on compression, RPM, and how much fuel and air you want to lift the valves 2. Advanced Inductions 418 with 13:1 compression and ported Ls3 heads: Vic Jr intake made 70X fwhp with a hydraulic roller.
1st off is the LSA block is stronger, piston oil coolers....etc and all but, check out the $ difference in blocks.
You have heads. $o rockers, lifter(all other top end parts) could be gotten on the premise of running a solid roller.
But off the head numbers could be as low as 650 but as high as 800 depending on compression, RPM, and how much fuel and air you want to lift the valves 2. Advanced Inductions 418 with 13:1 compression and ported Ls3 heads: Vic Jr intake made 70X fwhp with a hydraulic roller.
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Well let's see.
1st off is the LSA block is stronger, piston oil coolers....etc and all but, check out the $ difference in blocks.
You have heads. $o rockers, lifter(all other top end parts) could be gotten on the premise of running a solid roller.
But off the head numbers could be as low as 650 but as high as 800 depending on compression, RPM, and how much fuel and air you want to lift the valves 2. Advanced Inductions 418 with 13:1 compression and ported Ls3 heads: Vic Jr intake made 70X fwhp with a hydraulic roller.
1st off is the LSA block is stronger, piston oil coolers....etc and all but, check out the $ difference in blocks.
You have heads. $o rockers, lifter(all other top end parts) could be gotten on the premise of running a solid roller.
But off the head numbers could be as low as 650 but as high as 800 depending on compression, RPM, and how much fuel and air you want to lift the valves 2. Advanced Inductions 418 with 13:1 compression and ported Ls3 heads: Vic Jr intake made 70X fwhp with a hydraulic roller.
Damn I was thinking of 580-600rwhp lol
It'll be backed up by 6L80E also.
fwhp means fly wheel horsepower correct?
Last edited by 62nalide; Mar 31, 2015 at 11:32 PM.
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Joined: Mar 2013
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From: Studewood/Acres-Homes TX.
I must didn't get the Memo, about higher compression on pump gas. I heard one with 12:5 on pump gas.
But you could run e85 or race fuel, with a compression ratio of 13:1 or run a big as cam,
Yeah the auto will eat up some power but 600+ rwhp is Very much obtainable.
You would need to look over the whole combo, intake choice/ RPM/ cam type/ will be how much you get over 600rwhp.
Camster, Tim -87 Gray Hatchback, and Diet Coke all have done very similar builds all resulted in combos of over 600rwhp thru Autos.....with different heads and intake combinations.
But you could run e85 or race fuel, with a compression ratio of 13:1 or run a big as cam,
Yeah the auto will eat up some power but 600+ rwhp is Very much obtainable.
You would need to look over the whole combo, intake choice/ RPM/ cam type/ will be how much you get over 600rwhp.
Camster, Tim -87 Gray Hatchback, and Diet Coke all have done very similar builds all resulted in combos of over 600rwhp thru Autos.....with different heads and intake combinations.
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From: Mississippi
Just like Lil John said...... piston choice is critical. Got to watch how much stroke you go on a factory sleeve unless you don't mind running two rings on the pistons....... which is something I recommend for a car that's go see street/highway miles.
Ok build took a turn, after reading a lot on this section I wanted some more opinions on my current setup. 6.2L L99 which sets at 11.5:1 CR. So my plan is a LLSR but idk what specs are on my BES heads right now. So wanted to see if I can go big and or is too mig of a head can kill me? Going to swap my 3600 converter for a 5k so let me know what you guys think or is this setup maxed out?
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From: Studewood/Acres-Homes TX.
Pick the cam first then the Tq converter as you will be able to pick the correct stall to match the cam. Tony (BES) Ls3 heads are not that much different from any other Cnc program....if they were milled Piston to valve clearances need to be double checked.
So I can't spec the can to my heads and converter of choice? Thanks for the response.
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From: Studewood/Acres-Homes TX.
The Low lash cams make power but don't require over .700 *high lifts. But will make more HP than a hydraulic roller ....image your same cam with more Power and Torque and just running solid roller components. And keep everything else as is.
Try pricing a set of springs with over .750 lift for the street on a stock Ls3 head: I'm at .757 with a 408.
Pac-1238x springs $21 ea.
Pac- 1529x springs There made for road racing ....longer lasting $53 ea. My engine really wanted these.
Or the Nex Tek 221422 springs $31ea. I choose these...
Try pricing a set of springs with over .750 lift for the street on a stock Ls3 head: I'm at .757 with a 408.
Pac-1238x springs $21 ea.
Pac- 1529x springs There made for road racing ....longer lasting $53 ea. My engine really wanted these.
Or the Nex Tek 221422 springs $31ea. I choose these...
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Here are my thoughts on a LLSR camshaft with VVT. With these 400+ cubic inch motors we are going to have enough problems getting the power to the ground. The VVT will only exasperate the situation. On a 376 cubed motor or smaller than yes, VVT makes since.