Hey guys, I just bought an 83 Z28. It has the 305 engine with a 4 bbl. carb. I have a few general questions on it:

The car has a carburetor and a computer. Why? I always thought the computers controlled fuel injected cars. What functions would this computer control? The car also came with a Hypertech chip and a 160 degree thermostat. What performance advantages would this chip give over stock? (I must use over 93 octane gas, so it's putting a big hole in my pocket just to use this chip.)

Also, the car has a K&N air filter in a dual snorkel-type housing. But the tubings for the snorkels are missing. Where can I buy these tubes and where do they attach to in order to get air? (is it under the front bumper somewhere?) I'm not sure if the snorkel intake was factory on this car or not though.

Any help you guys can give me, or any other general information about the car would be helpful. Thanks guys!

 

The computer controls a mixture control solonoid that adjusts the amount of fuel delivered into the carb.

A hypertech chip doesn't help very much with computer-controlled carbs, so spend your money somewhere better.

The passenger side snorkle scoop is discontinued, I believe, so you'd have to take your chances in junkyards or on the net. The driver's side you can still get. They both attach to the upper radiator support (there should already be a couple holes there for the screws.

If your motor is an L69 then the intake was factory.

 

If that's a HO car, then you have a gem. It's one of the fastest third gen F cars.

Look at the VIN; if the 8th digit is H, it's the standard 4-barrel, option code LG4 if it's a 7, it's the L69 Teh LG4 was rated at 145 HP that year, the L69 at 190 HP. I never put mine on a dyno but others have said the rating is understated. I do know that my car would wax a 350 CFI Vette like it was standing still; that it had absloutely no trouble ever with any automatic 305 TPI, or any TBI (duh) car; it ran slightly ahead of the TPI 5-speed cars, and only lost to the 350 TPI (all automatics) cars above 100 or 110 or so.

The block, heads, and intake are the same on the LG4 and L69. However, the exhaust is completely different, the L69 has bigger manifolds & Y-pipe, and a converter with a 4-bolt flange at each end; and the long intermediate pipe is HUGE. It has a better cam, electric fan rather than clutch fan, and the dual snorkel cold-air intake. It also has 3.73 gears, and all of those 5-speed that year.

If this sounds like your car, it is one of just over 3000 produced. I hope it's in good shape, because like I said, it's a gem. It's one of the few of these cars that has any hope of becoming a "collectible" in years to come, plus it's a blast to drive,

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"So many Mustangs, so little time..."
ICON Motorsports

 

Whats the difference between the LG4 and the L69 and H.O.

 

L69 and HO are the same thing. L69 is the engine code for the High Output car. LG4 is the engine code for the standard fuel economy emissions friendly I think I have a good engine just because it's a V8.

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'89 Red Formula 350- 350 .060 over forged pistons 232* @ .020 cam Performer RPM Holley 750 DP Vortec 1.94 1.50 Accel Coil and dist. Hedman shorty headers Dual Exhaust w/ cutouts 1LE WS6 suspension, wheels, and brakes, 9 Bolt 3.27 Posi Edelbrock LCA's & Track bar subframe connectors 700R4 A&A snorkel scoop Eclipse Head Unit Delco Bose Speakers 2 12" Pioneer subs w/ 400 watt/chanel amp

 

Well, it turns out the car isn't a "gem" but just another Camaro hehe... it doesn't have the HO engine just a regular 305. I will look into buying the tubes for the snorkel intake though.

Are you sure that's all the computer controls? (if I disconnect the sensors for the water temp and oil pressure lines to install aftermarket gauges, will this affect the computer?)

Thanks again guys.

Oh yeah... I meant to say that the car already has the HyperTech chip in it, but that it's costing me money because the book says not to use lower octane gas with the chip. What extra performance does this chip give?

[This message has been edited by Chevy83Z28 (edited August 14, 2001).]

 

l69 has higher compression ratio

 

The ECM controls spark to some degree, fuel enrichment through the E4ME carburetor, EVAP canister purge, EGR system, Air Injection Reaction system, and if you have an automatic, torque converter lockup.

The carb looks a little like this:



The idle control solenoid, enrichment valve, and TPS are all connected to the ECM, and the ECM must have a TPS input for proper spark advance. It would be far easier to repair and maintain the system than to get around it.

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Later,
Vader
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"Let the bodies hit the floor!"
Adobe Acrobat Reader

 

I have an 84 L69, had two sold 1, now I gotta sell this one too And the worst part is I wont be getting another camaro for ages

Anyways I just wanted to defend the vettes a tad. My dad has a 72 vette, and my L69 gives a good fight but never ever wins. The vette really does kick you in the back of your seat no matter how fast your going or what gear your in. And as far as which is better to drive... id say the vette, only cause its bigger, meaner and louder, and generally more animal lol.

Sorry just had the feeling to be a vette guy for a while. At least its still chevy and not a ford lol

 

One more question about the computer... if I remove the catalytic converter to run a straight pipe (keeping the muffler,) will this mess up the computer? I have friends who have done this and they're "check engine" light is permanently on. I looked at the cat., and it has some sort of oxygen line I think it is that runs back up towards the engine. What do you guys think?