Lostoned

Reminds me of when I put a giant cam in a bone stock 305 without upgrading the springs...that was about 30 years ago

The valves would float at 5500 RPM but it sure worked great from 5200 to 5499 RPM LOL

Not sure how many times I mentioned I was planning on changing the cam in the LS, already said I was changing the carb and exhaust..those things will be tailored to work with the intake I got of course

Hopefully the combo I pick will be as good as the combo all the local circle track guys copied from me years ago (and still use on there cars today)

You guys are fun lets fight :-)

G Atsma

We still don't.... not that we care...

Haggar

No one said it wont run. However, it peaks horsepower at 5200-ish rpm in a 5.3, and drops off quickly afterwards. So, if you add a manifold that loses TQ everywhere below the redline, this isn't a mod/improvement. This is like sticking a restrictor plate on the engine.

Your other statements on carbs vs EFI make a few flawed assumptions:

1) The air/fuel mixture in the plenum is homogenous (it is not, as dyno plots with 8 individual a/f sensors show on a regular basis)
2) Carbs match EFI in efficiency, more or less. In real world, I would wager well over half the carbed "muscle cars" out there are giving up a significant amount of power/driveability due to the state of their tune.
3) The playing field is level for EFI vs Carb, in the LS world. In the end you are still constrained to the intake manifolds available, or that you make. The best manifolds tend to be the EFI ones.

Carbs work, if you take the time to tune them. Few really do.

What you see, going back to your original point, do LS engines take mods as well as Gen I's... If you took your motor, took your stock 190/191 cam out, put in a 224 cam, and cleaned up your exhaust, you would gain ~100hp, and could spin up to 7000 and utilize the manifold you have. The power is there, you just need to use the right parts. Go to 4.56 gears to utilize the higher rpm range.

How many stock Gen I's will gain 50-100HP with just a cam and spring change?

If it makes you feel better, plenty of EFI guys mismatch cams and intakes all the time, especially now with slapping turbos on everything. They just have a way to compensate for some of their poor combos by turning up the boost.

MuhThugga

No you weren't. You were 100% done with that engine and were disappointed with the results, which is exactly why you started this thread complaining about your disappointment with the results.

Must be some boring-*** races if they are all copying your set-ups.

truckdoug

iTrader: (25)

hello, it me

Kfxguy

iTrader: (1)

i didn’t know that telling you that you made a poor choice for an intake, is trying to tell you how to “build” a motor. I’m not making any assumptions either. I know for a mf-ing fact that that intake is killing the useable power range of your engine. I’ve tried a performer, performer rpm, victor junior and a weiand team g intake all on the same engine. The performer rpm worked better from idle to redline and made more power all the way around. The victor junior was a major dog. I tried spacers, air filter assemblies and tapered Venturi hats. I tried a carter 600, 750, quadrajunk, edelbrock, Holley double pumper 650 and 750 and a vacuum secondary 750 and the Holley 750 double pumper was much better all the way around with the vacuum secondary, quadrajunk and the carter 600 being the worst performing although the carter was very responsive and got good gas mileage. These parts were all tried on the same 350 crate motor I had in a Monte Carlo. I learned how to jet carbs and set timing curves at a young age. I also learned how to tune before HP tuners was a thing. I had a haltech real time tuning ecm in the 90’s.

I can assure my level of knowledge and experience with building engines, tuning fuel injection, building transmissions, rear ends and fabrication far exceeds yours. I have probably forgotten more than you know.

Tuskyz28

😂😂😂 @ Quadrajunk

TrendSetter

performer rpm is an incredible intake. very underrated.

67 goat

That was some awesome Friday morning reading. My favorite part is all the "conclusions" from the tried and true butt dyno.

Lostoned

Pretty sure my throttle is not opening fully when the pedal is too the floor, somebody want to stop over and step on the gas pedal so I can check it?

Just ordered an AEM wideband and 650DP, I figure the 650CFM will be too small once I change the cam and springs but there's nothing wrong with having a spare carb sitting around I guess.

indyjps

Lostoned, you swapped in a factory engine with about the smallest factory cam there is.

Built and raced sbc for years. Have 10 sbc in the shop with go fast parts stacked up to build them. Im still going to an LS. If youre just driving around town and spin the tires every once in a while, keep the sbc, you'll be money ahead.

The difference is if you want to make power, a lot if it and actually drive it. LS Heads are so far past sbc stuff, stock castings flow what sbc race heads do. Ive owned and driven multiple 400-500 hp sbc's, complete pain in the ***, but went fast. I can make 500 hp fairly easily with an LS with a decent idle. 600 hp and up LS takes some work but completely manageable and streetable.

Lostoned

Thanks for the advice but I actually got rid of 100% of my SBC stuff and I’m jumping into the LS world with both feet. In the last year I bought a 2003 Suburban for the engine, bought a 2003 s10 extreme to put it in and another 2003 Denali to learn how to tune...got the new hp tuner for that. First attempt at tuning with HP went very well. I was even able to make the worn out trans in the Denali shift like a dream by changing the settings in the computer..and that was after people on the internet were saying I had to get it rebuilt. I was surprised how much a person can change the shift behavior with just the computer....
Anyway the S10 is sort of my test mule, I planned to go straight to a turbo but figured I might as well play around with NA before I start spending a ton of money on setting up a turbo system

indyjps

Cam it. I have about that same cam in my daily 4x4 silverado, tows great but its a dog.

Factory performance cams are a cheap swap and easy to find tunes for. Heres some specs for 3 bolt factory cams.

LQ9 Cam Specs. 12561721
Duration @ .050 in. (int./exh.)196/201
Valve Lift (int./exh.)0.467 in./0.479 in.
Lobe Separation Angle116°
3 bolt

LQ4 2001-7
Dur @.050 196/207
Lift .467/ .479
LSA 116
3 bolt

LQ4 1999-2000
Dur @.050 191/190
Lift .457/ .466
LSA 114
3 bolt

LS9
Dur @.050 211/230
Lift .562/.562
LSA 122.5
3 bolt

LS2
204/213
.520/.521
116

LM7 flex fuel
Dur @.050 191/190
Lift .457/.457
LSA 115.5
3 bolt

LS1 98-2000. pt#12560965
dur @ .050 209/198
Lift .500/.500
lsa 119.5 117/122
3 bolt

LS1 01-02. pt#12561721
Dur @ .050 207/196
Lift .479/.467
lsa 116 117/115
3 bolt

LS6 2002-2003
Dur @ .050 204/218
Lift .555/.551
LSA 117.5
3 Bolt

Hot Cam
Dur @ .050 219/228
Lift .525/.525
LSA 112
3 BOLT

G Atsma

The late LQ4 and LQ9 cams are actually the same cam. Some places show a 201 exhaust duration, others 207. Either way it's a good cam for trucks in the 5.3, especially compared to the 191/190 cam they came with.

Lostoned

Honestly, it’s going to take me months to choose a cam but I’m pretty sure it won’t be a factory cam...

I’d like a cam that has nothing to offer below 4K, picks up like crazy at 4K and screams to 7k
like I was trying to say I give zero ***** about bottom end torque.

If you ever drove a SHO with the Subaru engine then you know exactly the power curve I like as a personal preference.

I want to max the potential of the heads and intake I got. I might be limited to around 6800 or less with the 706 heads ? since I think the valves aren’t big but I’ll research that point. It shifted at 5,800 in the suburban before I pulled it by the way.

then again there is a very good chance I will just order a wet NOS kit and play around with it (on the stock cam).... it’s a free country why not

G Atsma

The SHO never had a Subaru engine. Yamaha built them...

QwkTrip

iTrader: (23)

Right. You started with a bottom of the ladder LS that only made 285 HP when new. And you lost torque everywhere with your mods. It's going to feel like a barely warmed over 350 SBC. Nothing wrong with your perception about that. LS engines really really really like a good cam.

You have what is considered to be a "small bore" LS engine. They're not the pick of the litter if you're going to do a naturally aspirated build. The turbocharging crowd likes them for the thick wall cylinder liners though.

I would put the turbo cam in it and keep driving around until you can afford to piece together the turbo system. You're just going to end up with a dog if you try to do a high revving 5.3 with a manual trans and 3.73 gears.

Lostoned

Yes, thanks for correcting me. I really liked that engine. I’ve never driven a better V6 then that personally.

Lostoned

lost torque every where with my mods? Maybe you should check some dyno results with that specific intake and educate yourself.
5.3 is a small bore? Compared to what ? A 6.0 that’s 700cc bigger?
turbo charging crowds like the thick cylinder liners? Since when has that ever been a weak point in ANY LS?
until I can afford the turbo? Spending $ and having $ are different things.
5.3 with a manual and 3.73 gears must be a dog?

QwkTrip

iTrader: (23)

I saw your F-bomb.... just chill, bud. You mentioned a turbo is a lot of money. I was being sympathetic and proposing a cost effective pathway. No offense intended.

I've only made 2 short posts and am not one of the people arguing endlessly with you.

Regarding bore size, yes there are some groupings that are commonly accepted based on cylinder head compatibility. It can limit what heads you have access to, and ultimately how well your n/a engine can perform.

4.8 and 5.3 are small bore They can only fit the heads that came with them.
6.0 and 6.2 are medium bore. Must have at least 4.0" bore to fit the 6.2 cylinder heads.
LS7 is large bore. It's the only OE large bore engine at 4.125" and the heads aren't backwards compatible to any other engine.

You're a veteran engine builder, YOU should know that bore size matters.