Fuel Line - Aluminum or Steel

[v6spider]

I figured out tonight that I will have to test fit the engine again so I can make a modification to the fire wall to allow for clearing the distributor as it is in the rear of the engine. Then I'll have to tip the body back on it's side to finish with the fuel line.

Rob

[Daniel]

what is the wood frame or wall for?

[divace73]

I figured out tonight that I will have to test fit the engine again so I can make a modification to the fire wall to allow for clearing the distributor as it is in the rear of the engine. Then I'll have to tip the body back on it's side to finish with the fuel line.

Rob

Hi Rob

Like your work, is it worth considering a wasted spark only system set up so you can remove the dizzy altogether?

[v6spider]

what is the wood frame or wall for?

It's the frame that is holding the body it's side. I built a wooden frame instead of a rotisserie

Hi Rob

Like your work, is it worth considering a wasted spark only system set up so you can remove the dizzy altogether?

Going distributor-less would require me using an EFI setup. The cam I am using has too much overlap and won't work with EFI. So the dizzy is a necessity..it's an HEI SETUP like on small block Chevy v8 ... simple and very effective...

Rob

[v6spider]

what is the wood frame or wall for?

It's the frame that is holding the body on it's side. I built a wooden frame instead of a rotisserie

Hi Rob

Like your work, is it worth considering a wasted spark only system set up so you can remove the dizzy altogether?

Going distributor-less would require me using an EFI setup. The cam I am using has too much overlap and won't work with EFI. So the dizzy is a necessity..it's an HEI SETUP like on small block Chevy v8 ... simple and very effective...

Rob

[ClarkTheShark]

what is the wood frame or wall for?

It's the frame that is holding the body on it's side. I built a wooden frame instead of a rotisserie

Hi Rob

Like your work, is it worth considering a wasted spark only system set up so you can remove the dizzy altogether?

Going distributor-less would require me using an EFI setup. The cam I am using has too much overlap and won't work with EFI. So the dizzy is a necessity..it's an HEI SETUP like on small block Chevy v8 ... simple and very effective...

Rob

You can use a system like megasquirt to control spark only. Would be a very simple setup that would give you the opportunity to install a modern COP (coil on plug) system. All you need is a trigger wheel on the crank, or replace the distributor with a cam sensor. I would only recommend this if you wanted more of a project though.... and it seems like you have enough on your plate.

I have never heard of a car that wont run properly on FI? Where did you hear this? Is this a story that an old man that hates FI told you? The only functional difference in throttle body injection and carburetion is that instead of an analog fuel stream our of a jet (constant stream), you have a digital fuel stream out of an injector (pulses per second, variable). The fuel still gets atomized in the same fashion. You just have much better control over the fueling with a tunable FI system.

Educate me if I'm missing or not understanding like i should be.

[v6spider]

Hi Clark,
The cam in my engine is a comp cams hydraulic roller cam. Biggest one they make for the 4.3L v6 with 290° duration at .525" of lift(For full specs see: http://www.compcams.com/Company/CC/cam- ... d=561&sb=2). Heavy over lap will wig out EFI. Comp Cams spec recommends not using it. So I am going with the 4bbl carburetor I have been using all along. The 625 cfm Carter AFB. It works quite well as a matter of fact ...easy to tune and cheap. I'm well familiar with EFI. And I'm completely unbiased ... I will use either. Just turns out that a carb is a better choice in this situation.

Here's a quote from third generation . org that explains it better then I can.

Cam overlap is the period of time, measured in crankshaft degrees, in which both the intake and exhaust valves are open. At low RPM, this allows some of the fresh intake charge (i.e. unburned fuel and air) to leave the combustion chamber via the exhaust. It can cause a car to smell like fuel when idling, depending on how much overlap there is.

Now, keep in mind that there is an oxygen sensor that measures the amount of oxygen present in the exhaust stream. When it detects the unburned intake charge from the high-overlap cam, it tells the ECM that there is a lean condition (assuming closed loop is enabled). The Integrator, INT, then changes to compensate for this "phantom lean condition." As the INT moves, it updates the BLM, essentially dumping extra, unneeded fuel into the engine because the ECM thinks it's needed. Run like this for a little while, let the learn feature kick in, and pretty soon your car will smell like a gas station AND it'll cause all sorts of unusual characteristics at idle.

Rob

[divace73]

Hi Rob

Yes I was referring to Spark only, which is 'relatively' easy, wasted spark only requires the toothed wheel on the crank.

The modern fuel injection system can account for any settings you want, there is always the option of an open loop system (no oxygen sensor) where the system runs on predefined set values, however if you got the carb, I'd stick with it going complete EFI is a bit of a headache if the car/engine isn't already set up for it, however a spark only system only requires minimal modification and you can then program your curve how you like.

[v6spider]

Again, EFI will not work with the cam grind I'm using.... (see above) but I appreciate your sentiment..

Rob

[v6spider]

BTW folks its just as easy to tune a carb as it is EFI. Especially the carb I am running doesn't get any simpler than a Carter AFB 4 barrel. And super cheap. I spent $50 bucks on the carb used. The jet / strip kit to tune it was $40. and $50 bucks on the HEI Electronic distributor. The distributor advance curve is also tunable. The kit to tune that was $20. EFI costs way more and takes more time to tune IMHO... All the same I like both.
I'll post a video of the engine running when I get it going then you might see what I'm up against with EFI. VERY lopey idle with the cam I'm using but its perfect for the engine and weight of the vehicle. Lots of torque already in the 4.3L Vortec engine and the big cam ups the ante(HP) and makes it fun!

Cheers!
Rob

[ClarkTheShark]

Ok, So the issue isn't so much with injection as it is unburnt fuel/air causing a false reading lean condition to the 02 sensor during idle.That makes sense - of course you can still compensate for this with EFI if you like. Most systems have settings that wont allow the 02 sensor to make corrections under a certain RPM.

But there is nothing wrong with a carb. The carburetor is truly the mechanical engineer's dream. All the linkages/gadgets/valves/diaphragms and fluid dynamics that make it regulate fuel (Giovanni Battista Venturi - I knew an Italian was behind this madness)... simply amazing and often under-appreciated.

[v6spider]

Ok, So the issue isn't so much with injection as it is unburnt fuel/air causing a false reading lean condition to the 02 sensor during idle.That makes sense - of course you can still compensate for this with EFI if you like. Most systems have settings that wont allow the 02 sensor to make corrections under a certain RPM.

But there is nothing wrong with a carb. The carburetor is truly the mechanical engineer's dream. All the linkages/gadgets/valves/diaphragms and fluid dynamics that make it regulate fuel (Giovanni Battista Venturi - I knew an Italian was behind this madness)... simply amazing and often under-appreciated.

YES! That is the main reason. The other reasons are cost. I discovered it would be QUITE expensive to continue on EFI route. I sold my megasquirt II and was able to buy other parts I needed. In the first version of my car I had already spent mas time tuning the carb and the distributor. So those parts are ready to go and super simple. I can put the car together,drive it and enjoy it immediately without having to mess around with fighting the problems introduced by the large overlap that this performance cam has introduced into the equation. Not to mention I can change the jets and metering rods of the carberator with the carb installed on the engine. I also have a gauge on the dash that shows the fuel mixture as I am driving car. At a glance I can tell if the mixture is too lean or to rich and make adjustments if needed.

Cheers!
Rob

[v6spider]

I ran into problems trying to follow the original path that the fuel lines went. I have changed the path so that it is on the opposite side running tight against the frame rail..I'll post pics soon.. This also puts the fuel lines out of the path of crossing the exhaust. Much safer I think..
Rob

[v6spider]

Here's the change in route.. Much straighter shot than the stock fuel line route with all those twists and turns..

[ClarkTheShark]

And it also no longer goes inside the cabin. I think I will copy this.