670cfm Truck Avenger Carburetor

[adamforsythe]

I'm Done with Edelbrock carbs. I have gone through 4 this year (10) all together in the past 4 years for the same motor. The one i have now is dumping fuel into the engine from all 4 barrels all the time. My mechanic ripped it open and found some dirt in it and the Needles & Seats where a little our of wack. So he adjusted a few things and put it all back together and it's still doing it. He said it might come out of it. My fuel pressure is 6psi or VERY close to that. I really don't trust the carb. OR any carb from edelbrock any more. What should I buy for a street/DD 350 motor. I was thinking:
http://www.jegs.com/webapp/wcs/stores/servlet/product_10001_10002_750902_-1_10271
What do you guys think of The Off–Road Truck Avenger?
Or maby the
Holley Street Avenger Carburetors
http://www.jegs.com/webapp/wcs/stores/servlet/product_10001_10002_749689_-1_10271
Thanks
Adam

 

[rcamacho]

Everyone has their own preference in carburetors. I'm an old school Holley guy and have had very good results with their products on and off road. 4-5 psi should be sufficient for a mildly built engine. Much past 6psi the needles will start leaking on most carbs. Good fuel and air filtration are important as well.

In regards to the truck avenger line, they have the necessary modifications to deal with high angularity and vibration, however there appear to be some circuit timing issues on the earlier carburetors. In general, extended bowl vents, vent baffles, spring loaded needles are usually needed on any holley off road.
http://classicbroncos.com/carb_tricks.shtml

I have a fully rebuilt 780CFM Holley 3310-1 available but it's probably too big for most SBC applications.
http://seattle.craigslist.org/kit/pts/552466447.html

 

[Thunder]

670 is too much carb for a stock 350. Thats the problem many have with the Truck Avenger. They put that big o,L CARB on then have to geal with Hesitation, Dead spots, Missing under acceleration. You can try tune them and get them to run better. But then you get crappy MPG.
The 470 CFM would be a far better choice for a truck with stock 350. Better low end, Better throttle responce, Better MPG.
Either that or go with a Q Jet.

BTW 6 PSI is way to high for a stock 350 in a 4x4. 4 psi is about max.

 

[badmix]

670 is too much carb for a stock 350. Thats the problem many have with the Truck Avenger. They put that big o,L CARB on then have to geal with Hesitation, Dead spots, Missing under acceleration. You can try tune them and get them to run better. But then you get crappy MPG.
The 470 CFM would be a far better choice for a truck with stock 350. Better low end, Better throttle responce, Better MPG.
Either that or go with a Q Jet.

BTW 6 PSI is way to high for a stock 350 in a 4x4. 4 psi is about max.

heh. Im running the 670 street avenger (modified to truck avenger specs mol) on my basically stock 305CID. , My Qjet went south on me and I had planned to get a GM crate motor soon, so I got the carb that would work for now and could be used later. Ive had to tune it alot (more like detune it). I wouldnt say its too much for a 350. I do wish I wouldve gotten a 600 or 550 though for my 305cid. There is only slight hesitation on some occasions, I figured it was too much carb, but it could be just the fact Ive got a CARB and FI. FI is instant, a carb has some delay jus cuz of the mechanical properties.

I like my carb, but I think I wouldve been better off researching more and gotten a carb that was better suited for my needs. As far as gas mileage. When I drove back home I averaged 14.5 mpg with 32" tires and 4:10 gears and 700r. Once I hit the mountains it was all but over. I got well under 10mpg , Heavy ass truck and 305cid = poor gas mileage ingeneral. lol

 

[rcamacho]

The truck avenger idle and main circuits are jetted comparably rich to other holley carburetors. From what I understand with the check ball in the main jet passage they had to go bonzo on the signaling. A holley 1850 is a much better choice than a truck avenger if mpg is a goal since the idle and primary main jetting is much leaner. The 1850 can turn in comparable performance off road if fitted with the same basic modifications.

 

[adamforsythe]

Hello,
When I get my truck back I will check the Pressure again and if it's at 6 I'll put a regulator. in the line and drop it down to about 4. If that don't help i'll junk the old carb. I kinda like the 1850:
http://store.summitracing.com/partd...&N=700+4294925239+4294839063+115&autoview=sku
which it came in silver.
Thanks
Adam

The truck avenger idle and main circuits are jetted comparably rich to other holley carburetors. From what I understand with the check ball in the main jet passage they had to go bonzo on the signaling. A holley 1850 is a much better choice than a truck avenger if mpg is a goal since the idle and primary main jetting is much leaner. The 1850 can turn in comparable performance off road if fitted with the same basic modifications.

 

[rcamacho]

If you want an 1850, pick up one for 20-50 bones off craigslist or ebay and rebuild it. It's a lot cheaper. Toss in some baffles and spring loaded needles.

 

[Hogback Fabrication]

IMO you should look for a TBI setup for a stock 350.

This should be something you could install yourself (or have installed for cheap, a couple hours labor at most) and the cost of parts should be fairly cheap (~$3-500 for computer, injectors, ECM, wiring harness etc). A new carb could easily cost you that much.

Street or trail the TBI should run better for you.