Building Ls for Boost

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I'm new to the motor building scene.

I have a LS that is currently on boost and I want to build the buttom end. I am wondering if I should use the stock crank or should I be okay. I would like to see around 400 hp. I have a .63 trim t4 hybrid, 450cc injectors, 255 fuel pump, skunk 2 intake mani, 3in downpipe, 2.5 apexi worldseries exhaust. I'm on Chrome right now and have a great tune/tuner so that isn't a problem.

Can anyone give me an idea what pistons, rings, rods, and ect would be best for my application and can i get away with stock crank. Also should i sleeve the block and what is your opinion on block guards? Yes no? What bore should I use? Compression ratio. Also Head work cams, retainers, springs and ect.

I have a general in what i need just need the specifics in what to use.

I just need a run down.

Thanks for your help
Your stock crank will be fine, and I highly recomend sleeves at that power level. Block gaurds are shit, dont waste the money havin one put in. As far as pistons, rods, CR, and all that goes, just read some build threads. Theyll give you the info you need. You will need aftermarket though. If you want it to be reliable.
ehh prolly the 1500 range. What head work should i do. Is there any threads that would be helpful that you know of? Thanks rep points for all that helps me out
1500 hundred wont quite get you there. The sleeves alone are gunna run abouta grand installed. Beyond that a good set of pistons could run up to 500. Your bearings are gunna be about 200. Your gunna need a lil more fundage to get 400 horse.
You could take a chance and try to find a used sleeved block for sale, but remember when you send your block to Golden Eagle to get sleeved it comes with a warranty.
Okay so again with the sleeving of the block. A friend of mine has an b18a1 with 8.6:1 pistons and rings and some head work done. They didn't sleeve the block. how reliable and what kind of power could he possibly get out of it when he tubos it? Again I'm just trying to get an idea of what to do. Thanks
He could make 600 horse with it if he tried. But he'd only make it for a short period of time. I say that 350 is the max you wanna make without sleeves, for a reliable engine.

Also, Id say 8.6:1 would be a bit low for a daily driver. You wouldn't make good power out of boost, makin stop and go traffic a bit of a bitch. Personally, I would go with 9.0 or even 9.5:1. Your friend may like it though, and that's all that matters, how the driver likes the feel of the car.
ok ok. you want to make 400whp and beat the crap out of it every weekend? or every light?

if not i would imagine the stock crank with some forged pistons and rods and arp hardware will do the trick. I read where they boosted a bone stock b16 with highmiles,new HG with reused head bolts put down 500. It could have gone more.

no sleeves if you not going to crank up the boost every time you want to show off like an idiot.
since your on a tight buidget dont do a head job. just get it cleaned up and make sure you valves and seals are ok.
So does anyone else agree with the one above me about not sleeving? No it won't be a daily, but a weekend driver when it's nice out since I live in shity Ohio and the weather changes with no warning. Yes I would like to make atleast 400hp. The motor I was going to use has 85k on it but I just picked up a 99 ls for 300 that is clean and stock with crower cams apr head studs and one adjustable cam gear on the intake side. The part number for the cams are 62402. They are for mild over stock build and light n2o. Should I use them or stick with the stock cams because of the duration. Also why would the previous owner only run an adjustable cam gear on the intake side? Thanks
I read where they boosted a bone stock b16 with highmiles,new HG with reused head bolts put down 500. It could have gone more.

Do you remember where you read that I wouldnt mind reading that it sounds pretty interesting?
i saw that on an import mag about 2 years ago. i think it was import tuner or something. It it had a nice green hatch on the cover. it was headlined "bonzai b16" or something.

the pistons gave out at about 4xx something. Because the new porged pistons went mounted different on the rods than the stockers they went ahead and got some probe rods. THATS ALL THEY bought as far as i know. They ran it again and got the power gains they wanted.

i'm not saying its not needed. Its always better to have it for insurance. but your build was the reason they tested that b16. its was for people on a budget. yes it a different motor but it goes to show you how strong they really can be given the right parts and tuning. once gain i'm only suggesting not sleeving if your not going to max out the boost level everytime you get it in it..

why 400 anyway? especially on a street car.

let me see if i can find it online.
cant find it but i think it was features on modified mag. i cant remember.
Thanks man.....thats is crazy they were able to do that

their biggest thing was tuning. theyt claimed it was all in the tunining and that was the reason alot of high HP motor die early and the tuners or owners blame the parts giving out and week. The test was also out to prove the common misconception that the bottom was weak and cant handle that abuse. they defiintly bashed that myth. very true and i would have to agree.

to the OP: why do you want 400hp on a DD? I have never felt 400 FWHP but i can assure you 200-250 is plenty fun on the street.