Ask Bill about carbing a DeLorean and other K-Jet/Carb tangets

[congerz83]

On a side note, I thought this looked too cool to pass up at a Ford swap-meet. Technically, it's fairly accurate. Only 4 cubes off the actual displacement.

[Spittybug]

Do any of you guys that have added air filters directly on top (like the picture above) of any engine type (K-Jet, Carb, EFI) believe that the incoming air is therefore much warmer than if piped in from the pontoon? Given the meager air flow through the engine compartment and the exhaust pipes, cats and muffler all radiating heat straight up to the engine cover and sucked into the air cleaner, I would think there would be a noticeable difference.

Many D owners go so far as to remove the so called stove pipe pre heaters for this very reason.

This can be moved to a new thread by admin if someone should believe it to be inappropriate in the carb thread. It is my observation however that many of the carb conversions seem to have their filters right on top, hence these guys are a good bunch to ask the question to.

[Farrar]

I seem to recall Bill's answer to that was "It was good enough for the Pantera..."

I have thought about trying to add a fresh air duct to the air cleaner housing, but it would involve too much fabrication for my taste. Perhaps someone else will go this route and see if it adds any "performance."

Farrar

[congerz83]

A Dual-Snorkel fabrication like this one could work.


http://compare.ebay.com/like/3601552...=sbar&_lwgsi=y



Then if you could find any of those Legend Turbo Delorean side-scoops to feed it, it might keep things cooler.

[DMCVegas]

If I can help someone I will. K-Jet, carb or EFI alike. Can everyone claim the same?

Absolutely I can claim the same.

I honestly look at Carb conversions as just another form of customization. What the only thing that I ever took exception to was a couple of people people who rather than simply saying something like, "I just want to switch to a Carb because it's something I prefer.", they felt the need to justify the choice by putting down stock fuel injection and ultimately the car itself as well as other people. The thing is that you don't have to justify the switch at all. If you want to do it, and it especially helps you to keep the car on the road, and more importantly helps your enjoyment of your car, by all means go ahead. It was the context of the conversation before that led things in the wrong path. Here is the formula:

1. Negative Claim made against K-Jetroinc.
2. Rebuttal to claim offered.
3. WHY ARE YOU TRYING TO PERSECUTE ME!
4. Repeat. Cycle 2 switches claims to vehicle reliability. Cycle 3 adds personal attacks.

Like I say, to me a Carb is just a customization option. But attacks against the car are what really sparked the anger and escalated everything. It would have been like someone saying that they were doing a BTTF conversion simply because they didn't like the look of the DeLorean.

In any case though I'm just glad that this has all been put in the past so that people including myself can move on...

Admittedly I'm not gonna be nearly as much help as others with carbs having only ever really owned 1 car with a carb, and I sold it before wrenching on it. However, I do actually believe that I might be able to throw a little light onto the subject of the issue with Fuel Pumps. I think that I know what's going on, but it's gonna take a couple of stories here.

First story: Back in 2000 I was driving my car, and it just died for no reason at all. I couldn't figure it out (this was the day that my car almost got me killed trying to move it out of traffic). I got home and started checking for continuity. I was getting a solid 12V from the Feed jumping the RPM Relay and using an independent ground, but not when it Used the Ground wire. I don't remember the numbers, but it was pretty low and sporadic. So I was going to check continuity from the Inertia Switch's ground.

Now before going on, it's important to understand EVERYTHING that the Inertia Switch does, as well as what circuits it's integrated into as well as HOW it is integrated into them.

The first thing to know is that the Intertia Switch doesn't kill power to the Fuel Pump. It kills GROUND (or Earth as all the stickers on my car say). The 12V feed comes directly from the RPM Relay.

Second the Inertia Switch is not a SPST switch. It's a SPDT Switch where I believe the Single Pull inside of the Inertia Switch is the Ground. In position 1 with the Plunger down, the Switch connects to the Fuel Pump's Negative terminal in order to allow the pump to run. In Position 2 it connects to the Brown/Pink wire on the Unlock feed for the Door Switches and Warning Light on the A/C Panel. This is the Unlock Trigger Wire that senses (or in this case tricks) the Door Lock module into thinking that one of the doors has been unlocked and causes the other Door Lock Solenoid to pull open. Or in this case both.

Now for allot of you that didn't know this, you're probably wondering WTF?!? right about now. But the idea behind this was in case you ever got into an accident where the Inertia Switch was triggered, you doors would be unlocked for a rescue worker to easily gain entrance into the car to rescue you.

And now, back to my story:

When I went down to the Inertia Switch to check for Continuity on the Ground Circuit in Between, I discovered that the gray plug for the Inertia Switch was melted. Being tired, lazy, and already having the Inertia Switch trip on me once when I hit a pot hole I simply just unplugged it, and then cut the wiring harness for the fuel pump and ran a dedicated ground wire to the grounding point on the Radiator Bracket. Since that time it's ran strong and with the exception of a bad Charcoal Canister, I never had another problem again with the fuel pump.

Second Story: Back in 2004 I had my headlight switch start acting funny and working intermittently. I pulled it out one night after it refused to turn ANY of my lights on, and discovered that it had melted! I shoved a spare jumper wire that I had in to get the clearance lights on, and drove home with my high beams. Got home, found that the jumper wire was hot as hell! Checked all of my light bulbs, and discovered that my Left Front clearance lens had water stains inside, and had a cracked gasket. Pulled the lens off the fender and found that the bayonet socket was rusted beyond any repair. I ended up having to cut it out and then splice a new socket in as well as bought a new gasket. After that the jumper wire ran cool until I was able to put my spare switch in.

Now, what does any of this have to do with Fuel Pumps? Everything. See the rust in that light socket wasn't bad enough to cause a dead short, but it was enough to place extra draw onto the circuit. Not quite enough amperage at once to blow the fuse, but just enough to heat the wires significantly and damage the weakest link in the circuit.

I'd wager money that the problems with the Fuel Pumps are related to the Inertia Switch and corrosion inside. So far it's been the ONE place we can't get to, and I think this here is what's happening: Rust and corrosion forms and acts like a resistor that starts sucking amps. This places and extra load onto the circuit. And that load comes directly through the fuel pump. And seeing how fuel pumps are so susceptible to heat damage, I'd bet this is what's causing them. The K-Jet especially and EFI pumps probably have beefier components inside since they have to deal with higher pressures than Carb pumps. Not to mention that carb pumps probably also aren't usually installed with scenarios such as these where Inertia Switches are involved, let alone gas tanks next to heat sources.

On a side note I noticed that on Hervey's website he has a special note to check and make sure that the Plug for the Inertia Switch isn't melted. Hmmm...

I'd recommend checking resistance between the contacts on the Inertia Switch and see what you come up with. Likewise the next time someone complains about a noisy fuel pump and it's not an issue of the fuel lines touching the firewall or a seized diaphragm on the Carbon Canister, let's have them pull their Inertia Switch and check that plug for heat damage.

[stevedmc]

So far the fuel pump is holding up with the new ground wire. So far I've driven at least 450 miles today without a single problem.

Right now I'm at a nice Walmart somewhere outside of Montgomery, AL. I'm about to turn the parking lot into a camp ground and the Delorean into a camper.

[Ron]

Pleasant dreams!

[stevedmc]

I am proud to say I drove a total of 1278 miles since Friday. My car made it to Sean's house, and then Ron's (way up in the mountains with a tuna fish can baffle) and all the way back down to my house without a single fuel delivery problem at all.

Shoot, I didn't have any problems on this trip except for some thug in Biloxi that wanted to buy my car at a gas station. He claimed to have $10k cash money on him and he wanted to buy the car on the spot.

I now declare my fuel pump issue to be resolved. The new ground seems to have taken care of the problem I had before.

[congerz83]

I also have an idle problem... as well as an acceleration problem and a cold start problem... but I digress. My car will idle high when first started then go back to normal. Then, even after warm, it'll idle at about 2,000RPM until I punch the gas quickly. I'm guessing this has something to do with the choke. Also, at times, after awhile of driving, the car will idle very low 450-500RPM it will also stall at times in during this "mode" of operation. I'm also going to start keeping better track of my mileage because I think mine has dropped drasticly.

Also the car bogs down upon acceleration VERY heavily when you first start the car. Even during normal operation I cannot floor the accelerator without heavy "bucking" This carb conversion only has about 300miles since installation. I also changed the plugs shortly after the conversion.

[stevedmc]

My car will idle high when first started then go back to normal. Then, even after warm, it'll idle at about 2,000RPM until I punch the gas quickly.

This is normal. The fast idle circuit is designed to idle the car high until your choke is completely open. This is to keep a cold engine from stalling.

It sounds like yours is set a little high. Turn the fast idle screw after starting the engine and keep in mind the engine needs to be cold when making these adjustments. I also like to hold the choke plate closed while I turn the fast idle screw. You may need to lightly tap the accelerator to engage the fast idle screw before making your adjustments as well.

I'm guessing this has something to do with the choke. Also, at times, after awhile of driving, the car will idle very low 450-500RPM it will also stall at times in during this "mode" of operation.

Once the car is warmed up the fast idle circuit no longer operates. The car switches over to the idle jets. You will need to adjust your idle jet screws while the engine is hot to get it to idle where you would like.

Also the car bogs down upon acceleration VERY heavily when you first start the car. Even during normal operation I cannot floor the accelerator without heavy "bucking" This carb conversion only has about 300miles since installation. I also changed the plugs shortly after the conversion.

Not quite sure what is going on there. How wide/small is your plug gap and are you using new plug wires, cap, rotor, and coil or are you using 30 year old stuff?

Have you talked to Bill about any of this?