When I purchased my 82 it was without heads and the crossfire system so I am going to put a carb on instead of looking for a used crossfire. I think that the previous owner was running a carb because some of the wiring for the crossfire looks like it is missing. Anyway - do I need to have a return line since I am running a carb and what do I need to do to convert the in tank electric fuel pump to a mechanical pump?

 

I think you can just disconnect the power to the fuel tank pump, and install a mechanical pump on the motor. Make sure you buy a return line fuel pump, as it's better to have.

 

I am going to throw my disclaimer out first. I have never done the swap but I did own a 82 once.

I have to disagree with d'boy. I would not try sucking fuel thru a nonfunctional fuel pump. If your electric pump is working, simply add a inline fuel pressure gauge and regulator. Adjust the pressure to 6-7 psi and you should be good to go. Remember, you may need to change the distributor unless the previous owner already did so.

 

How much pressure does that '82 pump put through? I was going to suggest using it, but I thought regulating it down to 5-7 psi would eventually burn out that pump.

 

Is a 82 distributor different from an 81 distributor?

 

I was told by one of the few competent AZ employees around here (he looked it up) that the stock 82 pump was only 9psi, however some on this forum swear it is 15psi. If he buys a regulator with a return line he can loop it back to the tank or maybe tie it back into the flow.

 

Yeah, that changes my opinion too. I was thinking it was close to 40 psi. If it really is a 9-15 psi pump then a regulator and return line will work just fine.

 

My guess is the 81/82 are the same. Both run ecm's.

 

i just brought an 82, and the previous owner told me it has a fuel pump from an 85, giving the fuel pressure 'more than the measly 10 psi', as he put it.

 

tHE 82 STOCK FUEL PUMP RUNS 9-15 psi depending upon the age and wear of the fuel pump. Crossfire requires only 9psi to operate. I bought a new 82 fuel pump and it puts out around 14psi...the 85 fuel pump puts out 40 psi.

If I were you, I would ditch the carb idea and buy an Edlebrock TPi system. they are about $1000 and comes with the computer and wiring harness. The stock distributer is an electronic ignition type. If you go TPI, leave it or replace it with an excell HEI.

You can buy used crossfire set ups of the forum and ebay for a reasonable amount of $$$ around $100 for throttle bodies, $50-100 for an intake manifold. Computer about $75 and aircleaner assymbly for around $50-75.

I found a deal and bought a complete set up (intake, tbi units, air cleaner, computer and wiring harness) I paid a whole whopping $91.00 including shipping.

Good luck

 

Will a crossfire intake and throttle bodies off of a 84 work on my 82?

 

I think '84 was TPI. The Crossfire ended with '82 didn't it?

 

The '84 was also a CrossFire. Only 82 & 84 had it. You can run a 40psi pump on an '82 (I do). The TB has a press regulator built in to it.I had a problem getting the volume needed at WOT and the '85 pump solved that. As long as the system is in tune the CrossFire Injection works great.

 

Sweet. Great to hear from someone who actually is using a high volume pump. Since it's a stock '82 pump, it should work great for the carb and intake.

 

A FUEL PUMP DOES NOT CREATE PRESSURE!!!!! A FUEL PUMP DELIVERS FLOW!!!!!!

Pressure is the result of trying to force a certain flow through a restriction and a closed off restriction results in max. deadhead pressure, meaning the pump will cram so much liquid into the system against a closed off end resulting in this pressure.

Now, ANY fuel pump can be regulated down with a regulator. All 82s already have a return line so use it with a return style regulator. The spring load on the diaphragm sets the pressure, if the pump pumps more fuel into the system this would raise the pressure but the diaphragm opens at the set rate and bypasses the fuel back to the tank maintaining a constant pressure and also very important a constant stream of COOL fuel. This fuel is much less likely to percolate (vapor lock) Also the fact that the pump can keep pumping fuel means it's also cooled continuously, even when the tank is pretty empty and the pump not fully submerged

You can run a 40psi pump on a CFI because it's not a 40+ PSI pump, it's a pump capable of a flow rate that will maintain a dead head pressure of above 45psi. If you hook it up to a system with a regulator set at 15 psi the system pressure will be 15psi. The only situation where it will be elevated above the setting of the regulator is if the regulator or the return line is restrictive for the amount of fluid pumped/bypassed (or if the return line is blocked off)

these fuel pumps displace a volume, they do not create a pressure.

 

After looking over the engine compartment it looks like the previous owner was running a carb instead of the crossfire. I think it will be easier to put a carb on it then convert it back to crossfire. Can I use a 79 or earlier HEI non computer distributor?

 

yes

 

Then maybe you just need a wiring harness in addition to the intake. That isn't that big a deal. I'd keep the Crossfire or jump up to TPI or LT1 or something. Fuel injection makes it nice to drive, it is worth the effort.

 

How much is a wiring harness and were could I find one?

 

I have an '85 fuel pump regulated to 6.5 psi with a a Mallory MAA-4309 fuel pressure regulator. The regulator lets excess fuel flow to the tank after it feeds the carb, like the stock CFI regulator did with dual TBs.


The red "T" supplies fuel to the fuel solenoid for the nitrous system.