scottd. 09-11-2006, 10:35 PM Let me start with a little background. The last V8 I owned was 10 years ago. I recently purchased a 1982 Z28 with a 305. About 120K miles if the non working speedo is correct. (see tranny swap below..) She has an Edlebrock 600 carb, old edlebrock intake, all smog junk removed and a posi rear end. Somebody jerry rigged a TH350 tranny as a replacement for the original 200C. Tires are old and fairly dried up, and brakes are pretty squishy. Transmission, oil and power steering leaks all over the place. In sum, its a neglected car that Im slowly bringing back to life.
So, Ive got a new carb on, syncd as per instructions, and Im running about 5 degrees advanced timing. (Im still getting a little lifter knock??) For the life of me, I cant light up the rear end. Brake stand, low gear, whatever, she just wont break the rear tires loose. Squeals a little around corners, but nothing more. Now, I know a 305 isnt a monster engine, but what kind of performance can I expect from this thing? Am I missing something? I really need to know what kind of expectations I can have with this car. :confused:
teke184 09-11-2006, 10:48 PM it's probably the anemic lg4 motor...something like 130hp...and if it's not running right...probably less.
that would be why.
could be your trans is slipping too.
xpndbl3 09-12-2006, 02:19 AM try around 12 degrees base timing if not 14, although that motor is weak. the exhaust sucks on the factory setup as well....swapping to headers and a aftermarket y-pipe and 3" catback helps
LesPaulGoth 09-12-2006, 08:07 AM try around 12 degrees base timing if not 14, although that motor is weak. the exhaust sucks on the factory setup as well....swapping to headers and a aftermarket y-pipe and 3" catback helps
Make sure if you do this, you are putting premium in your tank, since you already have the knock issue right now. You might even want to try that before the timing to see if that takes care of the knock.
onefastgta 09-12-2006, 10:25 AM Like it was mentioned above, bump up the initial timing and check the condition of plugs/wires/ignition.
My old 305 would put on a smoke show when it was stock, so I think your problem is basic(like timing) unless the motor is down on compression.
Mr. Wolf 09-12-2006, 10:34 AM well i have a 305 with broc intake and carb, tes headers, and y-pipe, rebuilt with shift kit tranny, 2.73 gears open diff. and old tires. But i can smoke the **** out of them tires and still get amazing Hp but don't know how much though.
Damon 09-12-2006, 04:04 PM You're not still using the computer controlled HEI distributor, are you (has no vacuum canister poking out the side)? If you are, that's your problem.
You have to switch to an earlier non-computer controlled HEI if you ditch the computer controlled carb.
If the ECM sees the original carb is gone it throws the penalty flag (check engine light) and dials in a very weak timing curve. You'll always go slower in the end.
Fortunately, drop-in performance non-computer controlled HEIs had be had for cheap these days. There's many to choose from.
Mr. Wolf 09-12-2006, 04:31 PM so true, except, my 87's quadrajunk didn't have a an HEI dist. vaccum modulation sucks ass thingy.
Dave89IROC 09-12-2006, 05:35 PM yeah, the summit brand vac advance HEI is under $100, complete, cap, rotor, everything
scottd. 09-12-2006, 09:44 PM OK guys, now you are starting to worry me. The cap, plugs, rotor are new, as well as Accel ignition. I can only guess its one of two things:
1) Timing. Like I said, I started to retard the timing back to about 5 degrees to get rid of knocking. Guess I gotta run the expensive gas and bump the timing back up to 14 degrees. HOWEVER, anything past 8 or 9 makes starting this car a beyotch! I couldnt tell if it was the starter or battery, but when I retarded the timing the car became MUCH easier to crank over. Im afraid that 14 degrees will make it impossible to start. (and its a VAC controlled advance. Somebody just told me to disconnect it??)
2) Transmission. The car has a TH350 in place of the original 200c. Everything FEELS ok, (no slipping) other than an occasional hard shift between 1st and second. I attribute that to the vac modulator and the extra long rubber tube connected to it. Could there be some transmission adjustment that Im not aware of that could be hindering performance?
ws6transam 09-12-2006, 09:47 PM Yup, it sounds like a timing & tuneup issue. Check that distributor!
Then again, it could be the cam, or even the torque converter that was chosen for that TH350. Order yourself a Saturday Night Special from Summit while you are getting that distrib.
scottd. 09-12-2006, 10:18 PM What type of wear am I looking for on a distributor?
Im assuming the cam and torque converter are stock.
ws6transam 09-12-2006, 11:06 PM If the distributor has NO vacuum advance cannister on it, then it's probably electronic, and not providing the correct timing curve. It probably has a four wire plug on it that is connected to nothing but a malfunctioning computer.
If you have a non-CLCC quadrajet, then you need to convert the ignition to a vacuum advance distributor.
--
If you have changed the intake and carb, then you might find a lot of improvement by stepping up the cam profile, improving the exhaust with Edelbrock TES headers, and putting a 2400 RPM stall converter in that TH350.
Cams are less than a hundred bucks with new lifters. Stick with something between 205 and 218 degrees duration on the intake. (Summit SUM-K1300 is only $79)
Headers are $300.
Converters for TH350 are pretty much dime a dozen. Just check Summit.
Mr. Wolf 09-13-2006, 09:46 AM If the distributor has NO vacuum advance cannister on it, then it's probably electronic, and not providing the correct timing curve. It probably has a four wire plug on it that is connected to nothing but a malfunctioning computer.
If you have a non-CLCC quadrajet, then you need to convert the ignition to a vacuum advance distributor.
--
If you have changed the intake and carb, then you might find a lot of improvement by stepping up the cam profile, improving the exhaust with Edelbrock TES headers, and putting a 2400 RPM stall converter in that TH350.
Cams are less than a hundred bucks with new lifters. Stick with something between 205 and 218 degrees duration on the intake. (Summit SUM-K1300 is only $79)
Headers are $300.
Converters for TH350 are pretty much dime a dozen. Just check Summit.
I'm the one with the non-vac distrib. from fact. and i'm also the one whom changed intake, carb, nd has TES headers, 700r4 rules
Pneumatic_Tire 09-13-2006, 11:00 PM Do what everyone here told you, but do a compression test first and a fuel pressure test first. Get a repair manual at the zone or wherever, and compare your cars test results with that of what the manual says the specs should be. If all of that is kosher, then make sure the rear drum brakes aren't hanging the wheels up or overly adjusted OR soaked with brake fluid from a failing wheel cylinder up the rear wheels. Don't laugh, I've seen brake fluid saturated brake shoes/drums lock up the wheels big time.
Mr. Wolf 09-14-2006, 09:46 AM I've seen it too in motion and at a stand still.
ws6transam 09-14-2006, 10:17 PM I've seen it too in motion and at a stand still.
:confused: How does this relate at all to this thread?
scottd. 09-14-2006, 10:56 PM After all this, Im scared to do a compression test. The thought of re-ringing an engine scares me!
But, the brake thing, that brings merit. My brakes are shot. No evidence of leakage, just spongy as hell. Compression test to follow.....:mad:
Mr. Wolf 09-15-2006, 09:51 AM :confused: How does this relate at all to this thread?
2 posts back someone mention the problem could lead to drums locking up, and i've seen that happen b4 once while driving down the road and once while some one was coming out of a light. clear it for ya man , sorry bout the confusion.
Pneumatic_Tire 09-15-2006, 09:51 PM After all this, Im scared to do a compression test. The thought of re-ringing an engine scares me!
But, the brake thing, that brings merit. My brakes are shot. No evidence of leakage, just spongy as hell. Compression test to follow.....:mad:
Even if you take the drums off and don't see any brake fluid, that doesn't mean the wheel cylinders are ok. Take a pick, or flat head screwdriver and pull back each dust boot on both sides of each wheel cylinder, and if brake fluid comes out from behind them, then the wheel cylinders are shot, and is the cause of the squishy brake pedal(along with old original brake fluid im sure). :) Good luck, and when you get the car figured out, it will burn some rubber. It may be low on horsepower, but torque isn't all that shabby, even in stock form. My old lg4 could fry some rubber all day any day.
scottd. 09-18-2006, 05:30 PM Well, the dual exhaust should be here by the end of the week. That project should keep me busy until the leaves drop. Then she goen in the garage for the winter, where my last performance addition will be a Summit Cam. Ill do the brakes, and hope for the best. If she doesnt spin tires by then, Ive got bigger problems.
2nd2sex 09-20-2006, 01:53 AM gear swap
arocars 09-22-2006, 10:42 PM Sounds like your vehicle has high mileage, a worn engine, and highway gears. If your primary objective is to fry the tires, get a replacement differential with numerically higher gears. ...... Of course if you do that often, you're going to need to get a second job, because as soon as you start beating on that tired 305 and used t350, you're going to need a new engine and transmision
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