malc_p

Anyone want to help a newbie?
I have an '85 Z28 305 and the performance is just too flat with the standard 165hp ..... I have an Edelbrock performer camshaft and a Powerplus Crosswind manifold, both of which I am ready to fit, but what Carb should I go for? (Assuming that the stock Qjet R*ch*st*r also needs dumping!).
The Qjet has a tps and mixture control cable fitted so I assume it's computer controlled.
Under the hood I notice that the distributor has a 4-pin connector cable that goes nowhere .... the wire colours on this are white, pink/white stripe, orange/black stripe and a black/red stripe, which I can't find in the Chilton book. There are also one or two other cable connectors on the loom there with no connection - one with a green and a black wire, the others a two-pin and a three-pin connector with indeterminate colour wires! So I can assume that someone has been under there before me!
Any assistance gratefully received.

flyway190

Welcome to the board!

It sounds like someone replaced your distributor with a vacuum advance, or if not they tried to keep the computer from messing with the timing. If the distributor was replaced I recommend you get the right distributor, otherwise your car won't run quite right. CC carbs and non-CC distributors don't work well together.

If it is the original distributor, your computer will not advance the timing without that 4-pin connector plugged in. Look back behind the block on the driver's side for the other connector. The other two connectors sound like they would go to the ignition control module. Take off your distributor cap and make sure that your ignition control module has 7 pins. Does your check engine light ever come on?

Once you get your ignition straightened out you'll notice a big difference.

malc_p

OK the mystery of the missing connectors is solved - found the connector for the distributor taped up back in the loom! Reconnected this and it starts far better, but I haven't found a good bit of open road yet to check performance.
The other connectors are for the AIR - the exhaust manifold injectors are plugged off and the pump belt removed, and the EGR solenoid is not there.
OK back to the original question - I have an eye on a Holley 8700 650cfm - looks like the only thing I'll have to think about is a Throttle Position Sensor - how can I get round this? And will I have to do something about the Torque Convertor lockup?

Many thanks

Malc

five7kid

iTrader: (14)

You can't get around it.

Forgot the Holley. You have absolutely the best all-around daily driver carb for dual-purpose economy/performance possible. Get that CC q-jet and all its systems working, you'll be money and performance ahead. Get an EGR solenoid and get that working again. A.I.R. isn't that big of a deal one way or another if you don't have emissions inspections.

The power problems of the LG4 have absolutely nothing to do with the carb. Nothing. They are, in this order: air cleaner, exhaust, and cam. Fix those, and the heads will restrict power somewhat (porting the heads or going aftermarket will fix that). The ignition could then use upgraded coil and module. Then perhaps the intake could be considered for upgrade.

But, the carb and distributor with ECM control will still be better than any aftermarket choice you could make. Not only would you have to buy the Holley, you'd have to adapt it to your intake manifold, or buy an aftermarket manifold. And then a mechanical/vacuum advance distributor, and rig up some means for locking up the torque converter (various ways to do that, but none as good as what the ECM already does). It will have absolutely no more power than it does now, will not drive as well, and will get worse mileage. Why would you want to spend a bunch of money to end up there?

83_1/2 L69

Keep the CCC Q-jet. It will make over 300 hp on a 350ci motor with a simple secondary rod swap.