camaro86

which will you rather pick for performance a 1986 camaro z28 auto LG4 or a 1990 camaro rs LO3 5 speed? Which is faster when these both cars are stock and when they are modded?

Apeiron

Stock I'd probably pick the LG4. Modified I'd still pick the LG4, unless you were going to change the heads, in which case it doesn't make any difference.

Fast355

iTrader: (2)

LO3 is the only way to go. Main difference being alot less vacuum crap, more power stock, easier to mod, and easier to tune (once you get a prom burner). Plus you get the added driveability of the injection.

camaro86

why will you pick the lg4 over the lo3 5 speed Apeiron ? what if they do a homemade dual snorkel for the lg4 will the lg4 be faster?

305q_ta86

iTrader: (1)

I took the LG4. No computer burning for me. I just think carburetion is the way to go, not some in-between thing. I dont want to mess with computer tuning right now, and since I am on a college budget here, yeah. LG4.

Fast355

iTrader: (2)

I choose a LO3 and it has been a wise one. I added a set of TPI 081 heads, a 350 TBI cam, and headers on an otherwise stock rebuild, bored .040" over. I topped it off with a TBI setup. The total cost for the prom tuning stuff was $150.00 plus the laptop I already had. It took a little research, some soldering, and some patience. I am running 15.9s @ 88 almost consistently in a full size van with a 3.08 rear end. I am also putting out right at 240 RWHP and 310 ft/lbs.

camaro86

how can i get a lg4 to low or mid 14s

Apeiron

Mostly for the better heads on the LG4. The manual vs. automatic thing isn't that big of a deal for me, especially when you consider that the T5 isn't all that great of a transmission. Although, neither is a stock 1986 700R4, really.

A better air cleaner and exhaust would really wake either car up, but with the LO3 you'd still be stuck with the swirl port heads.

Once you've made a lot of modifications, it won't make any difference what you started with. You won't have an LG4 or an LO3 anymore, you'll just have a 305.

305q_ta86

iTrader: (1)

nitrous.

Or a good head porting (of the 416 heads) and a cam, headers, carb and intake manifold.

Oh, and weight reduction

Apeiron

14's isn't a problem on the stock Q-jet and intake.

305q_ta86

iTrader: (1)

Well, er, right. Intake manifold MAYBE, and carb, i guess I should have been more specific. I meant carb tuning, proper setup, etc.

camaro86

how about a 1986 z28 LG4 5 speed vs a 1992 rs TBI 5 speed? Which is faster when these both cars are stock and when they are modded?

Apeiron

Stock it would be close. The LG4 has better gears and makes peak HP at slightly higher RPM than the LO3, so I'd probably go with it.

When they're modded, who cares?

urbanhunter44

iTrader: (3)

Id go with the LG4 because:

1. Better heads
2. Carburated, so all you need to tune it is a screwdriver vs. PROM burning equipment
3. Z28s are cooler than RSs

Apeiron

Maybe, but the 92 RS probably has the same suspension as the 86 Z28, making it a moot point. The only difference then is the badging.

Street Lethal

iTrader: (16)

I'd go with the LG4. Burn a chip that only controls the LG4's electronic spark control, then slap on a much better carburetor of you're choice. You're in for a very nice surprise, result wise...

urbanhunter44

iTrader: (3)

Oh I'm well aware of that, I'm just saying, Z28s are cooler

MikeDirntRulez

True, but when you have a 170 HP Z28, then people laugh at you.

When you have a 170 HP RS, people expect it and don't laugh at you as much.

Apeiron

Both have ground effects, and nobody can read your badges in their rear view mirror anyway, so they'll be laughing at you either way.

five7kid

iTrader: (14)

Yes, like a real dog.

The ECM requires input from the carb, which it won't get if you try to "slap on a much better carburetor of you're choice", because there is no other feedback carb other than the stock q-jet.

camaro86

which will be easier to mod ?

Nate86

LG4, hands down.

Unless you are a real computer whiz. Then go with the L03.

Fast355

iTrader: (2)

I think the LO3 would be easier to mod. It may take a little more logic and thinking to mod the LO3, but when you get into tuning the engine such as at the track, I don't even have to open the hood or get greasy. Just punch in some numbers, burn the chip, and stick it in. The computer practically tells you what you need to do via the datastream.

Keeping the engine computer friendly is easy. Get you some 081 heads, go with the LT1 or LT4 (non hot cam) since the LO3 already uses a roller cam (you pay big money to do this in a LG4), use the Edelbrock TBI intake, perform the ultimate TBI mods, add some standard 350 injectors, full exhaust system including headers, add an open element, get a 2,000 rpm stall, and a EPROM burner. First change the BPWC to be compatible with the 350 injectors. Then tune the engine while driving under part throttle. My engine went from horrible to good in 3 times, it has taken me about 20 more burns to fix small things such as a high idle with the A/C on, the torque converter clutch locked to soon and unlocked too easy, etc. All I can say is the little 305 TBI and 3.08s will fry the tires in a 5,000 lbs G-machine.

Street Lethal

iTrader: (16)

I beg to differ.

I honestly don't know much about you're tuning skill, but it seems to work just fine for the tuners over here. They've re-programmed #1226455 to control the spark alone.

The quadrajet's TPS, and idle mixture solenoid...along with the O2 sensor, and electronic spark control, all work hand in hand to control the engine from the factory.

If you re-inspect my post, I didn't imply to just remove the CC-Carb... and throw on a Holley. You have to re-program the ECM (which I mentioned).

MikeDirntRulez

Just like fast355 said, it takes more to learn about the L03, but once you do learn it, it's a hell of a lot easier than dealing with an LG4.

Apeiron

I wouldn't even say one is really easier to tune than the other. You're doing essentially the same thing on both, just that in one case you're doing it mechanically and in the other you're doing it electronically. Which is easier is just a matter of preference.

camaro86

how much will it cost to change LO3 heads and if i change them will it perform better than the LG4?

Apeiron

That would partly depend on what heads you put on instead.

PhLaXuS

Sounds like he's asking if you can slap the LG4 heads on an LO3

Apeiron

You could, sure.