00pooterSS

iTrader: (40)

Okay I had to google it. It only makes sense the 4.8 rods would be longer with having a shorter stroke to keep the piston the same height as they are on the 5.3 and 6.0

The 4.8 rods are longer

You can slap the 4.8 pistons on the 5.3 crank and rods

For your destroker you'll need the 4.8 crank and rods to go with the larger pistons

Then hopefully you have all the floating/non floating rods and pistons lined out to work together. Depending on engine, year etc you'll have press pin or floating pin rods and pistons that you'll have to make sure jive together

Your destroker is going to get REAL expensive. One of the things you'll want to do is a solid roller setup. That alone gets pretty pricey. And it's a small piece of the puzzle. The oe hydraulic rollers aren't the greatest at real high rpm. You'll need an intake manifold and heads for it. And good rods and rod bolts.

Or get a gen 4 4.8 bore it, and intake manifold it, valve train and cam it and you'll be alright. Still.... it's $$$$

Bob570

The Detroit speed Camaro turns 8500 rpm with a 3.625" stroke, and that thing get the crap beaten out of it. I don't see why you think a 3.622 stroke couldn't handle 8000 rpm. Take the 6.0, upgrade the rod bolts, get a well sorted valve-train, a Holley hi-ram and send it.

sidewayZmoose

i’m not looking for revs with the 5.3. the 4.8 pistons will work fine with the longer stroke. they’re the same piston except the 5.3 has a dish. i recently found out that regular 4.8 pistons and the pistons used in the hi-po aluminium 5.3 (l33) are the same part #. what intake would you suggest for a 92mm throttle body? cheaper the better!

00pooterSS

iTrader: (40)

I typed part of that weird and to be clear i was just trying to point out that the rods would be different if you're trying to use 4.8 rods and to make sure you keep in mind they are different and to account for it.

What intake are you going to use the 92 on?

WARR throttle bodies have been real popular for working well and being low cost

sidewayZmoose

i haven’t made a decision as to what intake i’ll run. i‘m looking for something that’ll make more power than a stock truck intake and will work well with a 92mm throttle body, also something relatively affordable would be nice. it doesn’t have to be crazy efficient as it’s just going on a slightly higher compression 5.3 that’ll be n/a all it’s life. eventually i’d love to get the 706 heads cnc ported with bigger valves but that’s way down the road. any suggestions on an intake would be awesome. also still wondering if it would be worth it to get it bored to a 5.7?

G Atsma

The truck intake is surprisingly good. Don't be in a hurry to trash it.

00pooterSS

iTrader: (40)

If this is the one going on your daily that wont be high revving etc just put the truck intake and throttle body on it.

Too many conversations in one here and I can't keep up with what is what or why etc..

Why are you basing everything around a 92mm throttle body instead of seeing what you want, and getting it, and then deciding on the size that goes with it??? I can't anymore with this thread. It's making my head hurt.

sidewayZmoose

would a 92mm throttle body and aftermarket intake not make more power than a truck intake with a stock throttle body? i’ve heard of people porting and polishing their stock throttle bodies, does this do anything?

00pooterSS

iTrader: (40)

Only if the intake you choose is made to run a 92 mm intake and only if the intake you choose is better than the truck intake and only if that intake is right for your particular setup.

Look at this like wheels and tires. You don't find a set of wheels at a pawn shop and build a car to fit them. You buy a car and then find what fits it, and find out what fits based on your intended usage of the vehicle.

Yes porting a stock throttle body can help.

I'm glad you're sticking in there and asking questions, but I gotta say it seems like you know just enough to be dangerous. You want a 92mm throttle body before even knowing what intake you're gonna run. That's like buying tires before you have any idea what size wheel you're gonna buy. Or knowing what car you'll put the setup on.

sidewayZmoose

thanks for all the advice, much appreciated! what kind of gains would i see swapping from a ported stock throttle body and intake versus an aftermarket intake and larger throttle body? also still looking for intake recommendations.

00pooterSS

iTrader: (40)

On a mostly stock setup you'll see a few horsepower, around 5-10 max, may be as low as 2 or so, through a ported throttle body. Depending on how bad the original throttle body is. Most people also feel better response from the ported throttle body, even if it doesn't increase horsepower

On that same setup with an after market intake and throttle body you'll get around 15-20 ish at high rpm. Probably nothing below around 4000 rpm, maybe 5000. Possibly a drop in horsepower and response below that RPM with a big intake and throttle body

With a big bad motor with heads, cam, big bore, etc the intake and throttle body will become a much larger restriction and the power to be gained will be much more. Right now your intake and throttle body on a stock motor aren't killing much of anything. Headers and exhaust would do far more for you than a throttle body. It's about getting air in and out. It is hard to breathe through a straw, but not if the air is moving rapidly in that straw. If air is coming in fast into that straw it will fill your lungs without you breathing. That's the goal with an engine, get the air speed to do the work of cylinder filling to hopefully over fill the cylinder. Read into cylinder filling and volumetric efficiency to understand more.

The thing here is knowing whether or not your intake and throttle body are a restriction and how much of a restriction. It's only going to help if the intake and throttle body are suffocating the engine for flow.

Throttle body sizing also has a lot to do with response. Not just power.

There is no easy answer here, it's very complex.

When it comes to airflow, making it easy for the air to flow, is almost always, more important than opening the size of the hole the air flows through. Engines don't breathe slow like we do. They need air speed to make things happen well.
Air is like water at speed. It does not like to hit walls and have to make sharp turns. It will launch over a hump. It needs smooth transitions that help it keep up velocity (aka not slow it down) and that is the best way to make power because it is more efficient and gives the engine a better feel. A large hole flows plenty of air, but it does it at a slower speed. A smaller very efficient hole makes the air flow fast and that is what efficiency, power, and throttle response comes from.

All of that is a pretty dumbed down explanation too.

chrisfrost

iTrader: (8)

Hello everyone there is an article in an old "Hot Rod" mag entitled "The 350 Chevy Should Have Made" about 2 guys that took a sm bl 400 bored .030" to 4.155" and a 327" crank(3.25" stroke) Ford 300 rods(6.209" length) j & e custom pistons with higher pin location, 11 to 1 heads, stock cam, Rochester quadrajet, GM HEI ignition and long tubes and because of the increase in rod ratio were able to run 36 deg total ign advance 352 cu in developed 412 hp and 435 lb/ft tq on 87 oct pump gas. So I did My best to estimate the power difference using gen 1 350 everything else being the same and I came up with 150 lb/ft more tq and 160-175 more hp So the ls based 6.0 l block bored and the 4.8 L 3.27" crank is something that I and many others have thought about and some have done but I haven't seen anyones results so I'm going to search these forums. The 4.8 L pistons have the same compression height as 5.3 and 6.0 pistons and 5.7 pistons and 6.2 as well. Anyway good luck and if You do build the 6.0 block oversize bore and 4.8L crank and rods let us know how it turns out

00pooterSS

iTrader: (40)

Just leave the 6.0 3.622" crank you'll already have and bore it. You'll make a lot more power. No reason to swap to a 4.8 crank, which you'll also have to do rods. No advantage unless you're trying to rev it to the moon. And even then, using the 3.622 stock crank and rods you can rev pretty damn high, higher than most can afford to build the top end to handle.