TOPIC: New to the groove.

Hello all,

Hey Ron, I finally made it home from the conference after my tranny gave out.

I have a 24' RV sitting on an '86 Ford chassis with a big block 460 and Engelhard racing carburetor. I get a best of 7.8 mi/gal and 6 mi/gal around town. This will be my first mod. I also have a '94 Ford Explorer (with new tranny seals) that I will mod after the RV trials.

Ron, where do I find the training video that comes with the personal license. The DVD is a bit on the short side.

Looking forward to having the groove on.

RD

Hi RD,

Welcome to the Gadgetman Groove!

Ron has had extensive experience with a similar RV setup. So, he may be able to give you some hints on your rig.

Look forward to hearing more from you and "Welcome"

Hi RD,


Few things to look at for that "vintage", because it is a performance carb, ie: Selected for increased HP, your going to want to see about changing the metering rods to allow less fuel. Secondly, you want to check your fuel pump pressure. Since liquids don't compress the fuel pressure will dictate the potential fuel flow through the carb to the manifold. The mechanical pump on my Chevy 454 is at 6lbs, you will want less than that.

PCV hose, move it off the manifold and tie it in with the breather hose that would go to the air cleaner.

On your carb, just groove the primaries. Back your idle screw out to close the butterfly completely. Depending on how much material you have below the butterfly may dictate the bit to use. I used the medium bit on my Edelbrock.

For retuning the idle you'll want a vacuum guage and a way to read the rpm's,existing tachometer or other attached device. Set your rpm at 850, close one idle screw, adjust the other one for maximum vacuum, then open and adjust the first one for any additional vacuum. Bring your throttle idle back down to "normal" rpm.

There was a suggestion about reducing the idle screws and using the butterfly position into the groove "for effect", I tried that on my RV with poor results, you want to maximize your manifold vacuum and then adjust your throttle idle down to normal.

One of the things I did as a check with my RV (1982 w/Chevy 454/Edelbrock 750) was take a clean white rag after the engine has warmed up and cover the exhaust with it. Before and after. The amount of physical particulate in the exhaust will show up there and after it cleans the engine out that color on the rag will become a light stain if any at all.

If you have any questions at all, come on back here and post them, Pictures are very helpful as well. Take some of the 460 and put them up here so we can see what you are working with.

Welcome to GadgetmanLand

Karl Fortner
Tacoma, Washington

Thanks for the welcome.

Karl: Thanks for the tips. You made me realize I need to get my springs, rods, and ports in a row before I get started. Also, the carburetor is an Edelbrock #1411, so I'm getting my info straight too.

Next post will be in the ford forum with details on my pre-mod stats. I will try your cloth over the exhaust since I don't have an exhaust gas analyzer. Also, I think I'm going to deal with the PCV, adjust my spark plugs to maximum gap possible, and deal with a maladjusted automatic choke before I do the groove modification. Or, should I eliminate the auto choke and go manual?

Thanks for the advice, it is much appreciated. I'm not an auto mechanic, but over the years, I have rebuilt two of my engines and have had several top-end rebuilds (I've removed the head and taken into the professionals).

Thanks to everyone!

RD
Portland, OR

Hi RD. My experience on Carter/Edelbrock AFB carbs is the auto. electric assist choke needs at least seasonal adjustment. Loosen the 3 choke cap screws, rotate the cap towards front to increase choke on time/spring presure opposite direction to lessen. Of course in general you want less choke in summer, more in winter. The choke also activates the fast idle system. Often some increased idle speed is good even in summer and about mandatory for cold winter starts. There's an index mark center of side edge of choke cap, and a scale cast into the choke housing for reference. You have to get familiar w/ any given vehicle to se what the best setting on an AFB choke is.

There is a kit from Edelbrock to convert to manual choke, look at Summit Racing or Jeg's online for it, if you prefer that route. However I found that most all the choke cable assy's available are way too stiff, making the manual choke iffy unless you get a nice loose routing for the cable and avoid tight turns for it.

Personally I like AFB (which are a Carter design) carbs best for 4-barrel app's, and Holley the least. However Holley has the best reliable choke and Carter/Edelbrock
has the clunkiest choke! You just have to pay attention and find the happy spot for the AFB Choke...


Based on a good freind's experience (he has a 460 in a '75 Lincoln w/ a 625 Carter AFB) I recommend a 4 hole carb spacer under the carb. Use either a black plastic or Phenolic (looks like brown wood/cloth layers). Reason is heat isolation-that 460 in that motor home makes heat like a Nuke!! It will also help low end torque. My freind's Lincoln's AFB was Grooved by Ron, and it has run Very smooth, and after some tuning he says he has gained 25-30% in MPG!

My humble apologies if all this is Captain Obvious for you, but others might find it helpful as well!

Welcome to the Gadgetman Family, RD!

TracyG Gadgetman Reno

Hi RD,

What I have on my Chevy 454 is the Edelbrock 1411, so we're talking apples & apples.

I found that the metering rods are the most restrictive they have for that model carb.

I looked at reducing the fuel pump pressure ( 6 psi ) but the flow regulators usually require a fuel return line for the excess which mine does not have.

What I have found with the groove mod is that the pedal response is very noticable and running at highway speed my foot is barely on the pedal to maintain speed and doesn't take much more to accellerate.

Karl Fortner
Tacoma, Washington