How to offroad a Holley?

Replies to This Discussion

Permalink Reply by Sergio " MeatHead " on August 10, 2009 at 4:45pm

yea I had the same problem even with the edelbrock off road street avenger carb ...The best thing for to do is go with A Fuel injected system swapp your heads or get the fuel injected kit for sbc ...trust me it really works ....
hope this helps.....

▶ Reply to This

Permalink Reply by RECOVERY TEAM on August 11, 2009 at 8:39am

I have built several holleys for off-road use, there are several tricks to make them work on inclines. most of them are standard on the truck avenger. The most important is to have a carb with side pivot floats, or swap the center pivot float bowls with side pivot ones, witch is yours?

▶ Reply to This

Permalink Reply by timmy on August 11, 2009 at 6:42pm

the key is the vent tube.

▶ Reply to This

Permalink Reply by Brian Craig Rutter on August 11, 2009 at 8:15pm

I can,t affor the fuel injection,wish I could,but every other off road vehicle I,ve owened was a carb and they worked just fine,Scout(2bbl)Jeep cj renegade 304(2bbl,)80 chevy 3/4 ton(quadrajet),86 chevy 1/2 ton(quadrajet)84 dodge 1/2 ton(quadrajet),hmmmm,a lot of quads huh.I had thought about the vent tube,so I will be sure to try that.I don,t remember about the floats but I believe they are center hung.Do they make a side hung bowl for a 750 that I can fit to my proform?I also heard something about a spring load on the needle and seat,?Thank you all for your input,gives me some ideas to try.How would you tune in a factory fuel inj.on a motor of this cubic in.(I like my cam and heads),would rather not change them.What about a throttle body for a 454?would that be pretty close?

▶ Reply to This

Permalink Reply by RECOVERY TEAM on August 11, 2009 at 8:43pm

The vent tube is one of the tricks but it is very important to start with a carb that has side pivot floats like the truck avenger in the picture. a center pivot float Holley like most of them are, works good for drag and circle track racing but does not work good for hills. if needed a center pivot can be converted to side pivot but it is easier to start with the right one. The most recent off-road carb I built and is currently on my recovery truck is a 600cfm Holley with side pivot floats an off-road needle and seat kit (contact Holley tech for part # ) and no modification to the vent tubes (the vent tubes on my carb were extra tall to start with) it will run and idle on hills of 38 degrees or better just fine. Depending on the carb you have some of the other tricks are slosh tubes for the jets and baffles for the float bowls and or vents. If you give Holly tech a call with the list # (found on the front air horn of your carb) they can help you with all of the modifications and part numbers. I also installed on my carb a high idle solenoid used when I engage my hydraulic pump, this can be a nice feature to have with a manual trans when your feet are busy with the brake and clutch.

▶ Reply to This

Permalink Reply by Sick Air Joe on August 11, 2009 at 9:01pm

dido on the other posts, side pivot floats are best and I fixed a holley on the trail once with a piece of fuel hose connecting the vents together with a small hole cut out in the middle, I told that guy it was a bandaid to get him through the trail, but he liked it so much, I think he still runs it that way today yet.

▶ Reply to This

Permalink Reply by Travis on August 13, 2009 at 10:20pm

Yea i hav the holly truck avenger its a great carb justa lil tip i learned u can find one on ebay craigslist or a used truck avenger 670-1 it has a manafactor defect u can find one real cheep ther around call Holley and they will hav u send it in and they will send u a new one no charge the 670-2 ! good luck great carb no complants and im runnin big block 396 with a cam intake and a few extras 1ton axels gears and lockers 40in tires

▶ Reply to This

▶ Reply to This