96capricemgr

iTrader: (1)

Martin, care to comment on 4.8l powerband with the same cam vs. a 5.3l?

I would expect the 4.8l to need more rpm and potentially have a low rpm torque loss. More rpm could potentially cause a need for more spring too.

Point being I wouldn't use 5.3l results to pick a cam for a 4.8l particularly not with stock stall.

kad5118

i have read the cam comparsion when hotrod magazine took an ls2 cam and ls6 vlave spring gave it a baseline tune and it made just over over 380 crank hp.with other than stock heads and intake an holley efi controller.

I figured with ported 706 heads ported pro comp competion ls1 intake.and long tube headers,42 pound injectors should make close to 410hp crank power with the 4.8.and increase in engine vacumm.Just my speculation no dyno numbers to prove it but.I will run this cam in my 4.8 also .

Sales@Tick

iTrader: (3)

I really like doing the smaller towing and truck camshafts. It's really cool to put such a small duration, low lift camshaft in these 4.8/5.3/6.0 liter trucks and watch them gain no less than 35rwhp/25-30rwtq and up to 40-45rwhp/30-35rwtq in some applications.

The fact that these camshafts can use a 60.00 dollar set of LS6 valve springs that only need a 16.00 dollar set of valve stem seals is icing on the cake. Then there's the benefit of having such a stable mild lobe profile and such little spring pressure that the springs last for 75-100k miles.

It's really nice when a customer can re-use their stock locators, retainers and locks and keep the cost down on parts. It makes the package much more appealing to a guy that isn't trying to hop up his DD that he puts 10-20k miles a year on.

Even if they want to step up to a .580-.600 lift cam that uses a slightly higher pressure PAC beehive they can still use the factory components and expect no less than 50k miles usage on a set of springs. The demographic is there, I just don't think many of thought to or tried to capitalize on it.

I tried to buy a 2005, 2500HD, Z71, 6.0, 80E, Crew Cab short bed Wednesday. Went back to buy it yesterday and it was already sold. Had 125k on it and they wanted 17k for it. Gorgeous truck as well, burgundy with black fender flares.

I am actually test driving a 2005, 1500, Z71, 5.3, 60E, Crew Cab short bed right now. I know I can easily bring the power of the 5.3 it has up to the same level or more than a factory 6.0 with a cam and full exhaust along with a cold air intake. I might even put a set of milled 799 heads on it with a TBSS 90mm intake if I can find one. A set of electric fans would also help it out as well.

I think you can easily make one of these 1500 5.3 trucks tow really well, if not better than a stock 6.0. The only downfall is the smaller brakes, axles, tires and lower GVWR of the 1500.

96capricemgr

iTrader: (1)

kad5118, You seem to have seen what you wanted rather than the truth. It made about 400hp BUY floated the valves and that was on a 5.3l not the 4.8l discussed here which as I said I believe will need even more rpm.

Seeing as you made decisions like "ProComp" intake, 42lbs injectors(on an NA 4.8l) I would have very little faith in your judgement or your bench racing prowess.

Since you want to reference the HotRod article.
http://www.hotrod.com/how-to/engine/...st-comparison/

Based on that article if looking for a cheap GM grind with stock stall I would be looking at the LS1/LQ9 cam but even that will need to rev over 6000rpm by the time you rev far enough past peak to use it right even with a 5.3l.
Also when looking at that article ignore the 6200 and 6500rpm ltests on most cams as nobody is going to rev a cam that peaks at say 5400rpm as some did all the way to 6500 that was just magazine writer information manipulation at play.

Sales@Tick

iTrader: (3)

A 4.8 will not take the same camshaft as a 5.3, and I wouldn't recommend the same cam for a 4.8 as I would a 5.3 unless the circumstances were acceptable and the application could utilize it.

A 4.8 has a shorter stroke than a 5.3. They share the same 3.78" bore, but the 4.8 has a 3.27" stroke crankshaft and a 5.3 has a 3.62" stroke crankshaft.

Thus the 4.8 needs shorter cam timing to maximize and maintain cylinder pressure, especially in a truck and/or towing application. Specifically the 4.8 needs an earlier intake valve closing event and less valve overlap than a 5.3. Due to its shorter stroke the intake valve needs to close earlier, and it favors a longer power stroke due to the shorter stroke not putting as much work to the crank as a longer stroke. Lastly being that a 4.8 due to this shorter stroke has less displacement per cylinder versus the diameter of the valves, it needs less valve overlap to effectively scavenge the cylinder of spent exhaust gasses and to help start forward flow of the intake charge into the cylinder.

96capricemgr

iTrader: (1)

Thank you Martin. Every single day on here guys are recommending cams without considering displacement differences.

Tuskyz28

Hot Rod mag also installed a pair of L92 heads on top of a 6.0 then installed a crane cam 210/218 and the motor made 460 horse with 460 ft lb of twist to boot.

The editors said it was the torque monster cam of the show out of the cams they installed and I'm willing to get it will make a great towing motor.

96capricemgr

iTrader: (1)

The other side of that coin is we generally don't dyno test low speed throttle response and such.............

Tuskyz28

Very true! It'll be interesting if someone did that setup and tried it out in the "real world".

Bowtie316

iTrader: (1)

Guys tend to run much larger cams and recommend much larger cams on ls1tech than on performancetruck.net. If you search around there, there are lots of guys running "real" baby cams with good gains, on 4.8s and 5.3s. I chose the 206/212 for the 4.8 but ended up using it in the 5.3, it feels a little small and I could have gone bigger with the 5.3. The other things guys don't seem to pick up on, is a 112 lsa can really be an improvement in a truck over say a ls6 cam or LQ4 cam with 116-117 lsa.

Darth_V8r

iTrader: (4)

^^this^^

I put a LS6 Z06 cam in a 5.3 thinking i'd get 400+ HP out of it, etc, just like everyone always seems to think. That is a better cam than the LS2 cam. In a 5.3, it loses too much power down low, so would be even worse on a 4.8. Remember the LS2 cam is designed for a 6L engine with a 4" bore. The valve events are way wrong for a small bore, small stroke engine.

Having learned that lesson, What Martin is saying in this quote:

lines up with my experience. I've seen 4.8L engines with 243 heads destroy 5.3L engines with 706's even with stock cams.

OP, bottom line is, you'd do very well with a drop in cam, and if you really wanted to get more out of it, combine with a set of milled 243/799 would make for a dependable and fun power plant for that S10. Would still eat mustangs for breakfast

Boggies69

I've been researching constantly about this 4.8l cam swap, I think I'm definitely gonna go with a cam motion drop in stage 2, but I'm having trouble sourcing the LS6 springs...

These - Summit ( Chevrolet Performance Valve Springs 12499224)
Valve Springs, Beehive, 90 lbs. @ 1.8 in., 295 lbs @ 1.250 in., .570 in. Maximum Lift, LS6/LS2, Set of 16

OR

These - carshopinc.com(GM VALVE SPRING PACKAGE -LS1
GM Performance Parts 12499224 LS Valve Spring Kit)
Beehive style spring, 1.800" install height @ 90# pressure. 1.250" @ 295# pressure. Used on LS2 & LS6 heads. Max lift is .570, includes 16 of P/N 12586484.

thunderstruck507

iTrader: (18)

That's spot on as to my thoughts on the matter. A member here has a ls6 swapped Camaro, HioSSilver, and if I remember correctly he said to get the most out of a ls6 cammed 5.7 in a lightened fbody he was shifting at ~6,800 rpm.

Think about that. Then think about sticking that same cam in a 4.8 liter. It's a cam designed to run in a 5.7 liter, 243 headed, tight ratio manual trans car which weighs 3,000-3,200 lbs.

I would leave my truck stock before installing that cam in a heavier, lower compression, stock stalled automatic, with nearly a full liter less displacement. People do it (mostly because the cams can be bought cheap used), but I wouldn't be one of them when there are people like Kip or Martin who are able to fix you up with something ideal.

Engine dyno numbers are one thing. Real world results are a different ballgame. When I tested that cam for Kip he wasn't even concerned with dyno numbers...he wanted me to report on how it drove, behaved, MPG, tunability, etc. It was just icing on the cake I had a local shop willing to let me do a before/after dyno free of charge because the owner was curious. We tried to do a pull from lower in the powerband but the truck kept wanting to downshift from 2nd to 1st but believe me, the improvement begins right off idle.

(In the interest of being 100% objective I will note that the off idle response could be partly due to more precision tuning, but most people using a cam like this will be going from a stock or mild tune to a full tune as well. I kept it as close as I could by using identical timing tables and 89 octane fuel. I do not doubt I could get more power from the setup with in depth tuning to timing and a switch to 91 octane, but it's simply not worth the time and added fuel cost for how I use my truck.)

thunderstruck507

iTrader: (18)

Those are both the same spring. The ones I have are blue but in the past they have used yellow or bare with various color stripes.

redtan

iTrader: (5)

I just don't get how a tiny tiny cam with barely over .500 lift (smaller than most OEM cams) can gain 40rwhp on a an engine with iron manifolds.

Then you have guys that get cams in the mid 220s-230s with over .600 lift with long tube headers and they maybe gain 50rwhp.

Is all that duration, lift and supporting mods only worth 10rwhp if that?

kad5118

kad5118, You seem to have seen what you wanted rather than the truth

Ok so you can reads minds now wow give this guy a cooky


It made about 400hp BUY floated the valves and that was on a 5.3l not the 4.8l discussed here which as I said I believe will need even more rpm.

Ok thats good that you can put together sentences.excuse my lanuage but (no ****)wow you are really on the roll here lol.this guy seem to never amaze me at this rateagain.I know and understand that it was a 5.3 not a 4.8.The 4.8 will need more rpm to obtain those number based on the short stroke and longer rods.Its good to know that you can read too lol.

Seeing as you made decisions like "ProComp" intake, 42lbs injectors(on an NA 4.8l) I would have very little faith in your judgement or your bench racing prowess.

Why be with your reply and on top of that you didnt add anything useful.

A ported matched proComp intake with port match intake will be enough and more than what i need for a 4.8 to reach 400 -410 crank hp.If you have ported heads(which they didnt have in the article those number are reality.remember i am only after 400 -410hp at the crank not 500hp or 55999hp)42 punds is enough for injector size for crank numbers to be produced overs 370 hp crank not rear wheel.remember the 4.8 is a screamer.Its guys around my way that running them and they work for what they are.from 4.8s to 6.0s

Since you want to reference the HotRod article.
[URL]http://www.hotrod.com/how-to/engine/1307-ls-cam-test-comparison

Again

question why post an article that i have already seen thats kind of retarded 96capricemgr

kad5118

[QUOTE=Darth_V8r;18730546]^^this^^

I put a LS6 Z06 cam in a 5.3 thinking i'd get 400+ HP out of it, etc, just like everyone always seems to think. That is a better cam than the LS2 cam. In a 5.3, it loses too much power down low, so would be even worse on a 4.8. Remember the LS2 cam is designed for a 6L engine with a 4" bore. The valve events are way wrong for a small bore, small stroke engine.

Having learned that lesson, What Martin is saying in this quote:


i understand but im not expecting 420 plus number with cam only.I have long tube headers an intake ,bigger than stock injectors and hopeful some ported factory heads and tunning as well its possible its just more effort than whats needed for an 5.3,ls1 or 6.0.If not at least 400 hp.

96capricemgr

iTrader: (1)

30lbs injectors are sufficient for 500rwhp in a naturally aspirated engine, 42lbs are beyond grossly oversized. I know you will argue that but I trust real people with real experience rather than a calculator the guy trying to sell you larger injectors has to say. If 410fwhp is your goal stock injectors would have worked if not the 4.8l something from one of the larger engines.

I posted the article because you didn't understand it.

A 4.8l will rev higher given the same cam, not just have to rev higher to make the same number.

Tell you what, why don't you just quietly put this together, then set the world on fire with your brilliance exhibited in the final product.

Sales@Tick

iTrader: (3)

Funny, had a guy call today after reading this thread and I think I have him talked into a similar engine build for a truck he wants to tow with.

408", 11:1 compression, LS3 CNC heads from GMPP heads with GMPP "Blue" single springs, 215/223 115lsa cam, L92 intake, 90mm TB, full exhaust etc.

I think it will make close to 575hp at the crank and similar tq. The LS3 heads flow so much more air everywhere that less cam duration is required to fill the cylinder the same amount as a 317 or 243 head even with more cam duration. You'd need a lot more cam duration for the same size engine with 243 or 317 heads to make anywhere close to that kind of power.

Thus you get a great driving engine, great MPG, great bottom end usable torque and due to added cross section and flow of the LS3 heads, an engine that will red line at 6200-6400rpm and make peak HP around 5600-5800rpm. Basically not much different than the stock LY6 power curve.

You can have your cake and eat it too if you do it right!

I'd be glad to sell you the LS6 springs you need for 60.00 dollars plus shipping.

Kip's drop in cams are great choices.
Truck engines have tiny tiny camshafts. LS1, LS6, LS2, LS3 engines and other sports car LS engines have much more duration and valve lift. Thus the gains you're comparing really aren't apples to apples.

It's very easy to gain 30-40rwhp, possibly 45rwhp going from a 180-190 degree duration camshaft with .450-.480 valve lift to a 200-216 degree duration camshaft with .520-.560" lift even with manifolds.

It's going to take a lot more lift and duration to show a 40-60rwhp gain most see with sports car engines like I mentioned above. Due to the sports car engines having larger degree duration camshafts with more lift to begin with.

Also it's not so much the peak lift and max duration that helps the truck engines make those kinds of gains. The OEM truck cams have so little area at higher valve lift that it's pitiful. The aftermarket cam lobes have much more added duration at higher valve lifts. This allows the added flow that is available at higher valve lifts to fill the cylinder when there is more effective duration at the valve due to the lobe having more duration at higher lift. More time to fill the cylinder with higher amounts of airflow.

kad5118

96capricemgr;18730865]30lbs injectors are sufficient for 500rwhp in a naturally aspirated engine, 42lbs are beyond grossly oversized. I know you will argue that but I trust real people with real experience rather than a calculator the guy trying to sell you larger injectors has to say. If 410fwhp is your goal stock injectors would have worked if not the 4.8l something from one of the larger engines.

42lb injector for a turbo later down the line is not tooo big genius.Na yes i agree but not for a very mild turbo setup it isn't .your so freaking smart i guess you that too huh cleo

I posted the article because you didn't understand it.

you come across as having multiple mental issues on different platforms.to tell someone what they understand and dont understand base off of one sentence ,that wasn't even replied to you proves that your special, and i mean that in a short school bus special way.again your .Which only leads me to believe that you have some type of disorder and its called lack of common sense.lay off the antifreeze smoothies and you should regain the ability to think again.flush the toilet after your done with the bathroom and do the world a favor don't reproduce.

A 4.8l will rev higher given the same cam, not just have to rev higher to make the same number

Again thank you for being obnoxious and displaying what drugs can do to the mind.

Tell you what, why don't you just quietly put this together, then set the world on fire with your brilliance exhibited in the final product.

ok if i do this will you learn common sense