TOPIC: An example of the Kind of work I do--a rebuilt carb....

Hi guys, I'm just posting this here to toot my own horn. This is not about the Groove, I'm simply showing w/ a link the kind of work I do. This is an Edlelbrock Performer carb. I just rebuilt and listed on ebay. No Groove in it, just a nice clean carb. rebuild I did to sell this extra carb. I had lying around. This serves as an example of the kind of work I like to do. I worked on this formerly grubby Performer over the space of 3 days. Somebody is going to get a nice clean Performer, at a fraction of the new price. Cheers, Tracy G

Of course, the site host won't allow the link- So I'll just post some of the pics!


Tracy G

Well that was fast! The carb sold in less than a day!

Tracy G

Tracy,

The more I deal with my truck and its computer that seems to be the main problem with advancing MPG gains, the more I cry for a carbed car.
Looking at a 70's Nova but cant find one local that is worth it for the price I want.
If I find a Nova that I want, would you build a carb for that?
But if you do, I would want a carb that can be grooved.
There is no way a lousy ECU can get me there.
Then I can start to see real results.

PS...Have tried another rig up on the truck that seemed to be working finally.
Got 30-35mpg consistently for a 25 mile stretch with bouts of 40-70mpg going down hill depending on the grade from 1-4% or so.
Now on the way back today, the rig did nothing. Got 25-30 on the Scangauge the whole trip.
No wind both days and the same stretch of road.
Was hoping to see a hose came loose when I arrived, but no.
Will carefully look again but I see no change at first inspection in the rig which leads me to think the ECU AGAIN!

hi Karl. It's interesting you got some results on the Ranger, that then stopped. what was your new rig?

And yes I certainly could rebuild a carb for a Nova or similar-. but here's my thoughts.

The best overall results of Carb. grooving seem to have been for small engines: lawnmowers, etc. And, I think that was from Ystervark's use of the largest Groove possible. For cars, it must be remembered, that many carb's just aren't suitable to Groove. Carb's tend to have the throttle bore end just right below the throttle plate, leaving insufficient room to even place the Groove. I haven't made a study of this, but it seems that the small engine carb's are usually sidedraft designs, as compared to nearly all car carb's being downdraft. Difference being, the sidedraft small engine ones seem to have the necessary bore depth under the throttle plate, vs. the car carb's, in general.

another thing of carb's for cars, vs Throttle bodies in fuel injection setups is- compare bore sizes. Carb. throttle bores, are virtually always smaller diameter than TB's This is due to the need to have higher air velocity thru the carb's, to facilitate fuel entry thru the booster Venturis. TB's at least for port injection, the fuel and air are separate inputs, relying on high fuel pressure thru injector nozzles to facilitate fuel atomization. TBI injection setups are a compromise between carb. and port injection in bore size.

Point being, for given engine displacement size, injection TB's are always bigger diameter than carburetors. That means there is room for a larger Groove. That in turn means better results.

So I think that the idea of a magical return to the Age of Carburetion for a vehicle, is a fallacy, when viewed against the total experience w/ the Gadgetman Groove. Your experience w/ the Ranger has seemed to be a cursed one. I still don't know the exact reasons for that, you may be right re: the ECU. Any car that came w/a carb., esp. without an ECU (the cursed Feedback carbs) is by definition about 35 or more years old. To be worth of consideration, it will either be a classic something costing lots of $$. Or else, you will be faced with a restoration project, plus Rust... Pretty hard to find a decent condition late 70's Anything, as a good daily driver today. Also, w/ carb's the smaller the engine, the smaller the Carb., and a lot of 1 and 2 bbl carb's just aren't suitable to Groove.

I don't think, I KNOW, for vehicles, it is many times easier to get good results on port fuel injection vehicles, than it is for Carbureted ones. There have been some notable results on vehicle carb's, like my own Subie w/ Weber, and on a number of V-8's w/ the Edelbrock Performer or Carter AFB. But those 4 bbl's are on V8's... IF one is "married" to a carb. engine car, like me and the Subie then OK. I was already in that boat, before I knew of the Groove.

but, my opinion here, if starting w/ a replacement vehicle, I'd hands down look for something port injected vs. carbureted, even if I could consider a carb. swap.... I've done more than a couple carb. swaps, it is always more involved than first believed. Further, I've come to believe that the Groove and the famously named Pre-Groove Preps, are together far more effective than all the tinkering projects, HHO, and all the endless ideas out there. I should know, I've kicked over many rocks. You can have a rolling test bed vehicle (who, ME? ). Nothing wrong w/ that, if that's your Thing.

OR you can have something that really works... That's what my experience says. Not knocking you here, Karl, understand, you're a good guy. Lord knows you've been persistent!

over-

Tracy G

Hey Karl -
something I've discovered since I've grooved my vehicle is that (based strictly on the mileage readout in my instrument cluster, which I've discovered is inaccurate, but I think gives a good overall indication of injector duration and therefore fuel delivery) throttle position has a HUGE effect on the numbers being high or low or right on the money. If I wear thicker-soled shoes, for instance, I tend to not be able to feel how much I've got my foot in it as well as when I wear my beach sandals, for instance, and just by easing off the gas literally by a feather (and telling the ECU to close the throttle accordingly), the instantaneous fuel consumption readout drops, in some cases significantly...as in from 30ish MPG to the mid 40s...for example 7.3 L/100 km to 5.1 L/100km. that 2.2L drop (over half a gallon for 62 miles) adds up, you know?
Further, IIRC, your truck is a 5 speed; are you sure you're in the right gear? I'm certain you're concerned about lugging the engine, but there's over-revving as well, above the "efficiency zone" the groove creates, and that's where we obviously want to spend the most of our time. I mean, if you're doing 30 in 2nd at 2500, maybe 3rd might be a more efficient place to be; higher revs=more air=more fuel because of wider throttle...and a wider throttle means lower vacuum and a lesser effect of the groove itself. right?
That brings me to my next point: sometimes I need to "overshoot," speedwise, to get the auto tranny into the right gear, and then coast down to the correct/proper/legal speed.
Don't take this as a critique of your driving style or advice to break the laws of your jurisdiction, Karl, please. But everything considered, are you 110% sure it's the computer, and not the operator? Remember, they just do what the programmers tell them, based on how the operators use them. Maybe you should be telling yours some different things is all I'm saying, and that might mean you need to approch the computer a bit differently every time you drive.
(sorry for taking your thread off course, Tracy)

Well, in response, here is my take on the throttle position/RPM/gear thing.

I like to think about "anything" besides the Groove, that enables using less throttle at a given speed or load. Kinda playing the same record over again- but, anything that boosts torque, OR decreases any form of a parasitic loss, helps here. That's what the Pre-Groove Preps, our other side mods, are about. I won't go on here re-listing those things, and I haven't come up w/ anything new in this area lately.

I've found it useful to think about these things, since everything begins as a thought. I did see something really weird years ago, online. Info about it seems either dated or getting harder to find. It was the Ram Implosion Wing. Seriously strange Star Trek lookin' thing some guy had made and mounted atop a van, I think I remember. The guy claimed some remarkable gains from it, if it was true. It would cause serious distractions to fellow drivers, if it was installed. Assuming the thing actually worked. It looked like something to put on one of the "Art Cars" that show up here for Burning Man!


Tracy G

Greg,

My driving style is more toward a hypermiler since I love to coast and don't jack rabbit.
I would say in an average trip that I coast 5-10% of the way depending on the distance and how many highway miles. Coming to an exit, depending on the highway and traffic, I usually coast about a half mile when nearing an exit. Same goes when seeing a red light or stop sign. I like coasting to the light with the intention of never stopping but still moving when the light changes so as having to avoid a complete stop.
As far as the throttle position, I know that the TPS gives the engine the signal on how much fuel to inject hence why my thought on enlarging the groove to keep the plate directed toward the groove at cruising speed.
The driving style would be the last reason I don't see mileage gains.
Right now am dealing with a vac leak somewhere. Getting a reading of 15 on the LTFT which decreases to single digits at highway speed. Checked all the points I know with ether but cant find.

I'm just like you Karl, when it comes to coasting to a stop...in fact I know for a fact that I've irritated other drivers cruising up to a stoplight that I know will turn by the time I get there so I don't have to be on the brakes to stop or hard on the gas to get/keep moving when it turns green.

Fuel trims - vacuum leak...what about an exhaust leak? if the O2 sensors are telling the computer something funky, that'll impact fuel delivery...maybe that's worth a look? I seem to recall discussing O2 sensors with you on here in the past...especially since you're seeing the trims drop at highway speeds with more exhaust gasses flowing past them. manifold gasket? the gasket between the manifold and downpipe? somewhere up near the engine maybe, around the upstream O2, since the downstream one basically verifies that the cat is doing its' job? Have you maybe got a bad/cracked or incomplete weld somewhere?

What about a clogged/metled cat converter? I remember my uncle had a performance/efficiency issue on his old B2200 that was fixed by replacing the cat itself because exhaust heat melted the honeycomb inside. (this is, of course, assuming the design hasn't changed significantly in the 20-ish years between his truck and yours...)

I dunno. we've been fighting with your truck for some time now, and I'm sure you're quite frustrated to say the least...but we're still trying to resolve this and get you happy. One of these days I'm sure we'll find the angle to come at this from that will make the recipe pop.

Watch yourself with that ether around hot exhaust pipes!!

Karl, assuming here that Greg has a point on the exhaust system- fastest way to get it checked, is visit a muffler shop. Despite any attempt to sell you their work/wares, it's a bunch easier to let someone who does it all day every day look at it IMHO. It could help to describe any driveability or symptoms if there are any.

Plus- have ya poked 'round in any Ford forums to see if someone might be talking of anything similar? Taking advantage of group-think, and somebody else's experience.

One more thing. I still wonder about how you said that the restriction to the idle air circuit caused a higher idle RPM. Usually it would be the other way 'round. Going out on a limb here, if it's getting too much fuel at idle, and if it maybe is dropping out of closed loop at idle. Then that could explain this, maybe. Does exhaust smell worsen at idle? Stinky rich? No codes for the MAP sensor?

Are there any bad/strange driveability issues, or does it run OK all the time, and just get bad MPG?

When you are coasting to a stop, or just coasting, is it in neutral, or in gear?

Tracy G

Thanks Greg, even if this isn't the case with Karl's truck.. an exhaust leak, will allow air (Oxygen) into the gas stream. In the right (wrong) location, it could be making Mr ECU think the engine is lean...simplistic I know, but true..

Tracy G