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Chevrolet 5.3L LS Budget Engine Build - 644HP Junkyard 5.3L

Buy A Budget LS Engine, Add A Cam, Carburetor, Headers, And-Oh Yeah-A Procharger Centrifugal Blower, Mix 'Em Together To Build A...

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Centrifugal superchargers generally don't add dramatic torque at lower engine speeds, as was evident with this engine as well. Because our engine is only 325 ci, it doesn't make a ton of torque at lower engine speeds. In our case, it took until 4,700 rpm to make more than 500 lb-ft of torque, but considering we're talking about a 325ci engine with stock heads, a torque output of 1.68 lb-ft per cubic inch isn't bad. Our cast-piston short-block limited the safe boost to 12 psi and total ignition timing to a mere 22 degrees to ensure the engine would not experience detonation. The combination of detonation/preignition with cast pistons is a recipe for disaster, so we were conservative even with 100-octane Rockett unleaded fuel. We ran out of time to try a pump gas combination, but 18 degrees of timing with around 8 to 9 psi of boost would probably be safe and still make 590 hp. We'd suggest adding water injection to this combination just to be safe (see sidebar).

Test 1|
This was the normally aspirated baseline using a nearly stock long-block. The only real changes were the Comp hydraulic roller camshaft and matching valve-springs. We also added a Victor Jr. single-plane intake manifold, a Holley 750 carburetor, and a set of 13/4 to 17/8 stepped headers.

Test 2
This was the test for all the horsepower marbles. Using 100-octane unleaded race gas, the only addition was to hook up the ProCharger P1SC supercharger and a Quick Fuel blow-through 650-cfm carburetor. As you can see from the numbers, this was a huge improvement in power.


TEST 1 TEST 2 DIFFERENCE
RPM TQ HP TQ HP Boost (PSI) TQ HP
3,500 359 239 428 285 4.2 69 46
3,700 348 245 428 301 4.8 80 56
3,900 356 264 441 327 5.5 85 63
4,100 359 280 465 363 5.9 106 83
4,300 360 295 482 395 6.3 122 100
4,500 362 310 493 423 6.9 131 113
4,700 363 325 504 451 7.4 141 126
4,900 370 345 515 480 7.9 145 135
5,100 376 365 528 512 8.4 152 147
5,300 379 382 530 535 8.9 151 153
5,500 377 395 538 563 9.5 161 168
5,700 374 405 545 591 9.9 171 186
5,900 366 412 546 614 10.7 180 202
6,100 356 414 541 629 11.1 185 215
6,300 344 412 531 637 11.5 187 225
6,500 -
520 644 11.9 - -
Peak 379 414 546 644 11.9 187 225
Average 363.7 339.8 503.2 485.2 8.2 139.5 145.4
Averages were taken from the entire dyno pull every 100 rpm, while our chart shows only the odd rpm points.

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194 comments
Cathy Hall
Cathy Hall

It really doesn't matter what engine you build as long as the mechanic knows what their doing and I think the mechanics at fast are the best. Way to go Travis and the crew!!!

Age Cobra
Age Cobra

You don't a lot of cubes and the best big block are Fords and ChryCos.I never pit Aerican Muscle over each other anymore.It is Muscle vs imports.

James Hayward
James Hayward

Buicks arent high winders but pull like freight trains.......ive got a 70 buick gsx, 455, stage 1, 4spd , all original, and runs like a raped ape...........

Peter Papaleo
Peter Papaleo

No find three so when the first two blow up you have a third spare

Peter Papaleo
Peter Papaleo

Umm I didn't think the 5.3&4.8 were ls engines. Aren't they Vortec truck engines?

Craig Serrano
Craig Serrano

I'd go 4.8L with a turbo, if these guys can tune them and squeeze 6-700hp out of a stock bottom end, cam, and a pair of heads, and get 30mpg. Why would you need anything more on the street? Other than more's never enough:)

Bob Strongarms
Bob Strongarms

LS = easy HP in a compact & lightweight package. No need for a big block anymore unless you really want to run one.

Branden Knives Ross
Branden Knives Ross

as sweet as the buick 455 is, the block simply cannot sustain much more than 600 horse, not that you need much more than that

Christopher Spielvogel
Christopher Spielvogel

its easy! big turbo on jy LSx motor and start stacking up spares bcuause they pop like poprocks.

Michael Palombo
Michael Palombo

LM7, 5.3L stroker engine from the chevy trailblazer- can be boosted up to 1000hp! On stock internals!

Ted David Burrell
Ted David Burrell

Love the mix of new and old. Too bad this one appears to be coil-on-plug powered. Those aluminum heads must be worth their weight in gold!

Ken Dennis
Ken Dennis

woodstock woody...step 2 take ford motor in for scrap beg for gm back take ford scrap money get a coffee and get back to building

Teahartea Vatara
Teahartea Vatara

TÉMOIGNAGE: Si vous voulez faire un prêt entre particulier merci prendre contacte ( essemevo@gmail.com ) avec cet Mr Philippe qui m'a rendu le sourire aux lèvres. J'ai plusieurs collègues qui ont aussi reçus des prêts à son niveau sans problèmes au lieu de vous faire avoir par des individus mal intentionnés qui prennent pour travaillent à escroqué les innocents et je publie ce message parce qu'elle m'a fait du bien avec ce prêt et ne vous découragés pas parce que moi je me suis fait avoir mais j'ai rencontré cet monsieur honnête et Généreux alors prenez contacte avec lui: voici son Email: essemevo@gmail.com Merci de faire comme moi et envoyer votre demande pour obtenir votre prêt en 48 heures au plus. MERCI DE PARTAGER CETTE INFORMATION POUR AIDER NOS FRÈRE NOS AMIS ET AUTRES.

Gene Stribling
Gene Stribling

we don't like them if we got one for free and all the parts for it we say no

Doug Nelson
Doug Nelson

Im doing a 5.3 in my 76 nova. Help me go low buck... Please. Like under $1000.

Don Morris
Don Morris

You can make over a 1000 hp on a small block

Matt Pound
Matt Pound

$4,000 you can have 800whp all day with a 5.3

Scott Petty
Scott Petty

I don't consider $7,000 a budget build. I could have an inline 6 with more power for the same cash.

Scott Petty
Scott Petty

nevermind. Budget build = $7,000. lmao.

Dennis Jones
Dennis Jones

LQ4 with Twin Turbos that is my dream engine

Michel Loup
Michel Loup

or pontiac sd 421 dual 4bbl 488 hp stock

Michel Loup
Michel Loup

302 dz best smal block or 454 best big block

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