JoeMama54

Hello everyone I am relatively new to the third gen website. I already have a flowmaster exhaust on my 1984 305 and everything else is pretty much stock. I want a little more power. I was wondering what add-ons I should get to gain more horsepower and torque for faster acceleration. I was intending to get hedman headers but would my money be better off spent else where? possibly a performance camshaft or something else? Keep in mind that I live in California and my car needs to keep up with all the smog regulations. I have a pretty low budget at about $1000. Any suggestions would be appreciated, thanks!

PurelyPMD

iTrader: (3)

The HO was a pretty nice combination right out of the box. 750 CFM carb, the better factory cam, 3:73 gears. Tuned properly it should perform pretty well.

RedLeader289

iTrader: (2)

750 cfm on a 305? did you mean to type 650?


Best bang for your buck would be making sure the thing can breath well, good exhaust and headers.


Take whats left over and buy new rubber parts for your suspension (or go poly) and it'll really freshen up the car.

jokerZ71

Going with a bigger cam won't have much effect unless you get the exhaust opened up,so,I would start there.A better intake would also help.

PurelyPMD

iTrader: (3)

No, I didn't mean to type 650 - signature says 305 H.O.

L69 had a 750 CFI E4ME Rochester carb.

JoeMama54

What specifically would you recommend for suspension parts? My suspension parts are pretty old, there is alot of sqeaking and cracking when I turn and sometimes when I punch the gas theres a loud thud that sounds like something is hitting each other. I was thinking subframe connectors would help get the power to the ground or possibly something else? Thanks

jimw67

Find the source of the clunk. I'd be willing to bet either worn/sloppy motor and/or trans mounts or rear end bushings. It also could be in the rear itself - pulling the cover and checking backlash and carrier side to side travel will confirm the condition of the bearings and gears. And changing the oil if it hasn't been done in a while will not be a waste of money either.

I wouldn't think that you're going to make enough power to be concerned with subframe connectors, but others might disagree.

yaj15

iTrader: (3)

https://www.thirdgen.org/1983-chevy-camaro/


To better compete against it’s competition, the 5.0 liter H.O. engine was introduced mid-year (March 1, 1983) in the Z28. The H.O. engine came with a higher lift and longer duration cam, dual snorkel intake system with a “5.0 Liter H.O.” decal on the air cleaner, specially calibrated Quadrajet carburetor, lightweight flywheel, electric cooling fan, bigger 2.75 inch exhaust, Corvette style wide mouth monolithic catalytic converter, 5.0 Liter H.O. exterior/interior identification, and came standard with a 3.73 rear axle gear. In 1983, the L69 was only available with a 5 speed manual transmission.

New L69 cam: L69 305 H.O.
190 HP / 240 Lb.Ft.
Tach: Yellow 5000
Red 5500

Lift: Intake .410
Exhaust .423

Duration: Intake 320
(crank) Exhaust 320

jmd

iTrader: (4)

Get headers in there. I don't know what headers are 50 state legal for the F-body, but I believe there are options better than Edelbrock.

Make sure cat is in good condition / flows well.

A bit of cam and new valve springs makes an L69 more fun than stock. Don't go any bigger than the old Compucam 2050 though.

Moving the powerband upwards is going to make a higher stall converter helpful too. Go moderate and keep lock-up for highway mpg.

The intake manifold won't help much by itself. If you do have to remove it, I like the ZZ4 manifold. Again, only after cam and exhaust are done.

A lightly modded L69 can be a fun driver.

RicerEater

iTrader: (2)

I don't know if it legal but a better Y pipe with duel cat will help it flow way better. Headers are nice but when your Y pipe strangles it headers achieve very little. A cam then porting out your intake manifold and heads with better springs will net you a good improvement but nowhere near massive.

LiquidBlue

Personally, I'd focus on a tune-up and getting your suspension tightened up. Make sure all your bushings and joints are tight, struts and mounts are working good, between that and a good tune-up, you'll break your budget pretty quick. You'll get way more bang for the buck this way. A nice tight car, that is plenty zippy. You can blow $400 on headers and only gain 5 hp. If anything on the exhaust, the old cat converters are pretty big power robbers from what I've read. That might be the first place to fix in your exhaust setup, making sure it will work down the road as you move on to replace other exhaust components. If you can't resist headers, don't fall for cheap ones, you'll just end up with exhaust leaks, and a crappy sounding car and end up throwing them away. If you haven't discovered rockauto yet, go over there and you can do some pricing on different ideas of things to fix to help you plan your budget. If your shocks and struts are blown, and you plan on keeping the car for a long while, then some really good shocks and struts and going to eat half of you budget already, and they won't do you justice until you get everything else on the suspension tight.

Back in the day, these cars were limited in what they could do horsepower wise due to emission standards and limits of affordable computer technology of the day, but GM had no restrictions on how well the car could handle other than making an affordable car to the public. They should handle and brake pretty nicely, first and foremost. Then you can worry about power later. Get that pony handling! (which means braking too)

PurelyPMD

iTrader: (3)

Of the early 3rd gens, you've got the best they had!

jmd

iTrader: (4)

The L69 was the best third gen cat of of the 80s until the duals on some '89 models. This is because of size and having contemporary monolith technology far, far better than the beads that filled some 70s converters. Those were bad.

5hp is unlikely. The heads on the L69 are not peanut port. The intake valves are not the small ones. The intake isn't a big restriction. The Q-jet most certainly isn't either. Headers address the biggest restriction actually, and it really is the first, logical modification to a good running condition stock L69.

Except for a travel-stop on the secondary air-door, there's no emissions restriction when it comes to the secondaries of the Q-jet. Only the primaries are ECM controlled. So full throttle is quite literally as-you-tune-it and as mechanical and "unlimited" as any carbureted vehicle.

I'm in agreement a tight chassis is a good thing. The harder durometer 1LE solid bushings (is Moog making those for the front and rear of the third gen?) would be an upgrade on an early third gen.

LiquidBlue

^^^ Ya, I admit, I don't really know what the horse power gain would be by adding headers (I've seen Hot Rod magazine numbers that don't amount to much), but my point was with a 1K budget, I don't think that is the first place to start refreshing this car because it would blow a large portion of that and limit what else can be done. Only a guess, but there are probably plenty of tuneup issues that would be much better bang for the buck, carb may need rebuilt, tuned, sensors, plugs, wires, ignition, pvc, filters, etc is all going to add up. These guys are saying 53 hp with a tuned exhaust and a few other bolt ons, but I'm afraid that would break the 1K budget and leave you with a squeaky, ill handling car : http://www.superchevy.com/how-to/pro...lock-bolt-ons/

PMD - Nice video comparison cool to see. I always thought the 928 resembled a Pacer

JMD - are you saying the cat converters that were put on these cars as efficient as today's aftermarket replacements?

PurelyPMD

iTrader: (3)

I would agree on the maintenance first approach. Check bushings, trans & motor mounts, brakes, tuning components and fuel delivery prior to doing any enhancements.

I've found it's best to get a baseline first, then measure your improvements one by one.

JoeMama54

Thanks for the suggestion. I was planning on getting the suspension fixed up first before getting headers because I feel like that is priority. A tune-up also sounds like a good idea, How much do you think a tune-up would cost? possibly including a carb rebuild. I have the stock Rochester carb.

jmd

iTrader: (4)

That's kind of a broad question. Converters now are sold in versions that don't meet 50 state standards, but the CA versions will cost ya.

It would be interesting to see actual flow tests of a GM L69 cat vs. a newer similar sized one vs. straight pipe vs. the !#!%$%% necked down versions (like in that article and especially the aftermarket L69 cats thesedays including the Catco that goes back 15 years at least.)

Having driven a few L69s for lots of miles, I'll say the L69 cat isn't worth removing for power.

A 928 with C5 or C6 drivetrain would be cool, no matter what you say.

If I lived in a country that made it terribly difficult to increase CID of a car, that build in the article above sounds okay at a 53hp gain. But I don't, and I still wouldn't use triangle tube Edelbrock headers.

RedLeader289

iTrader: (2)

Shocks/struts, LCA bushings, sway bar bushings and end links, outer tie-rod ends, shock mounts. . .I may be forgetting some things. Basically any worn out rubber parts that you see. You'd be surprised how much difference freshening up the 'basics' will make.


SFC's would help tighten the car up, but you aren't making enough power for them to be a "necessity" right now. I'd focus on getting everything else repaired/replaced and then put those in as a nice finishing touch.

JoeMama54

What do you guys suggest as far as a tune up?

RedLeader289

iTrader: (2)

Plugs, Wires, Distributor Cap (with brass terminals), and a K&N air filter.


Go ahead and pick up a spare Ignition Control Module and keep in the glovebox/console (these cars eat 'em).