new carb

[mikeyo]

hey i have the giant 4 barrel carb on my '76 440. i was told i should get a 4 barrel with smaller barrels to increase my mileage from 6 to 10 or so. what should i look for? will i find what i want at a scrap yard? i must get better mileage!!
thanks guys.
mike.

[HarryClipper]

I recently went to this site: www.thermoquads.com and found out a lot of information about these carbs.  

By the way, a good friend of mine use to be a "Holley Carb Rep" back in the 80's, and he said (TODAY!!!) that the "Thermo Quad" which is your "big carb" OEM from factory was a WAAAYYYY better carb than a Holley for many, many reasons!

Back when in 1975 to 1980, I was a performance salesman at a Speed Shop in Los Angeles, and we sold a lot of Holleys and had LOTS of comebacks, fires, etc.

My best sales to Chrysler product vehicles, were... (with POSITIVE results) Edelbrock intake manifold with using the factory "Thermo Quad"on it, K&N 14" Air Cleaner, better ignition wires (today MSD 8.5 MM), Headders, and mufflers, which resulted in more power and in many cases, better mileage!

I have read here, concerns about "headers".  I can not imagine how "cast iron" can not HOLD MORE HEAT.  An item with a smaller total mass in general, with a LOT more air moving around it besides, would not STILL today be more efficient (especially with ceramic heat coatings to boot!), and...especially in light of the fact that soooooo many vehicles today come OEM with headers!

My experience has been that "OEM" parts are designed around a budget ("Bean Counters" ..."BC"), and aftermarket (Better Results Oriented..."BRO") is about true RESULTS!

Doug Thorley still makes headers for our vehicles and they are available with ceramic coating from them for additional cost.  Simply add "C" to the part number.  Go to their website and you can see the headers listed with picture and all!

Good Luck!
Harry Clipper

[Horst]

10mpg with a 440 Clipper??
Maybe....... at 40mph, with nothing in it, substantial tail wind, a gentle downhill slope.............
I think the best you can hope for is 8.5 - and that is if you make some mods and drive very conservatively.
7.5 to 8 is typical.
7 is quite common - people who drive fast get even less.

I'll never forget several years ago when I went with my brother-in-law to look at a nice Clipper he eventually bought - it had a very strong motor, big four barrel, nice exhaust, etc.
The owner bragged about how fast his Clipper was, and how he routinely drove it 75and even 80mph!! when going on trips.

I asked him what his mileage was at that speed, and he said:
"oh, about 4 or 5 miles per gallon, but I don't care about mileage, I just want to get there!"
He was an RV repair man...............

[alhnelson]

Just a note on gas mileage. Since we bought our clipper 3 years ago, I installed a new 440 engine, added Thorley ceramic coated headers and dual exhaust, and replaced the thermoquad carb with a quadrajet. Originally, we were getting about 7 mpg or worse. We live in Colorado west of Boulder at an elevation of 8500 ft and most of our driving is up and down mountains at altitudes between 5200 ft (Denver) and about 12,000 ft (mt passes). Most of my work on the engine has been to gain power to handle our elevation and try to maximize fuel mileage. Last year I installed a air fuel gauge and retuned the carb for a better match to this altitude by changing the piston spring and jet sizes. I then took the Clipper down to Boulder' elevation of 5400 ft and did about a 100 mile trial driving at normal speeds and managed to get 10.6 mpg at that elevation. So, it is possible to tune a Clipper to get 10 mpg especially if you live at lower elevation and are driving flatter roads. We also got between 8 and 9 mpg on a trip that took us over Rocky Mt. Park.

That being said, we just came back from a trip through the mountains where I'm sure our mileage was not as good. With my current tuning, it runs fine at high altitude but one can not escape the combined effects of up and downs with grades between 6 and 10 percent and the loss of power due to altitude. The moral of the story, there are adjustments that can be done to help mpg, but when the carb secondaries cut in for that extra hill climbing power, there goes the fuel economy.

Regards,
Al

[bigray]

I've been getting between 7 and 8 mpg but on Friday I replaced my fram air filter with a K&N. I also got a push-in type filter instead of having the line go from my value cover to air breather. In addition I ran a 2 1/2 air intake hose from the breather to near the front bumper so the engine can take in some cooler air.

If you don't have this setup you may wish to try it. I was impressed with the results. I got close to 10 mpg while running the cab A/C as well as
the roof air during my trip to the beach this weekend!

Heck, I've consider putting in an overdrive or gear vendor to get better mileage. The K&B filter was $39, the air hose was $13 and the push in filter was $6. The saving I got was worth every penny!


Happy Clippering!

[Rodney]

I am running the Edelbrock 600 cfm in place fo the thermo quad.
much better deal. better bottom end power and I don't see any loss of top end power. The OEM carb was leaking and made for hard starting the engine, the Edelbrock with the electric choke fix all of that. haven't had a chance to really check mileage but I would guess it to improve some..
Bigger is not always better.
If you go with the edelbrock they sell an adaptor for the trans kick down linkage-- you would need that and an adapter to the intake if you are running the stock intake manifold. other that that it is a good swap. IMHO.
Rodney

[KEYSJUNK]

I made the same changes that Rodney has done last year and what a difference.  No more leak overs and hard starting. Have not checked the mileage, but the performance seems must better.