Advantage to switching carbs for my application?

[pjoll84]

Hi everyone,

So I’ve had two very successful camping trips with this B200 you have all been helping me out with… even hauled a boat with no problems! The only thing it didn’t like was idling in a grid lock… got pretty close to the upper side of OK temp wise… might install an electric pusher fan for those events


Anyways, I digress… question to the gurus (which I know might be opening Pandora’s box) but I have a rebuilt Carter bbd… would there be any advantage to throwing on a 600cfm Holley? Engine is a 318 w/ 727 and 4 3/4 rear.

 

[WileE]

No.

 

[Geoff 2]

Only if you want to spend more on fuel....

 

[MWbirdLOVER70]

To me it’s power on tap if you need the extra boost but don’t tip into unless you need to and treat like a 2bbl

 

[Runcharger]

Cool rig. I think the 4 barrel will get worse gas mileage with not that much more torque. Those lil ole 318's tow better than they should in my experience.

 

[R413]

Just adding more problems, then the trans linkage must be right or burn that up.

Why do you need/want a 600 Holley?

A Holley is the last carb I would put on this vehicle

 

[71Beeper]

What about using a Holley 500cfm 2bbl carb?

 

[toolmanmike]

What about using a Holley 500cfm 2bbl carb?

Those don't get the best mileage.

 

[toolmanmike]

Probably the best carb would be a Thermoquad or new equivalent and a decent intake with smaller 318 sized ports.

 

[kramer]

To me the BBD two barrel carb isn't that great of a carb for your application, if all your looking for is fuel economy and not much reserve power the BBD fits the bill. I wouldn't use the 600 Holley carb, one option is I would look into is a factory style Thermoquad setup or possibly run a Quadrajet or if running a square bore carb a 600 cfm would be preferable but the closest to that size that I would use is an AVS2 650 Edelbrock. The nice thing about the AVS you can easily adjust when the secondary comes in so you can fine tune it for your aplication. You can have the best of both worlds of fuel economy and power with the correct 4bl carb. IMO

 

[pjoll84]

Thanks for all of your comments everyone… I guess I posed the question for the simple fact that this is a stock setup carb/engine application for a B200 van… not a Moho, so I was curious if there was a better application for the needs…

Overall, this thing sings at 55mph on the flat at around 22/2300 rpm. We have two VERY LONG and VERY STEEP summits on Vancouver island… and with the foot to the floor in 2nd gear, it was a struggle to stay above 40mph. Just as I reached the top, so did my temperature gauge which was very close to creeping over the normal zone… and the coasting down the hill would restore it to normal (strangely enough, giving it some gas on the way down cooled it off quicker then just coasting )

Was it a big deal? Not really, I threw my four ways on and shimmied up the hill. Maybe that’s as good as it gets? Hence the questions.

Appreciate all the help!

 

[RJRENTON]

Hi everyone,

So I’ve had two very successful camping trips with this B200 you have all been helping me out with… even hauled a boat with no problems! The only thing it didn’t like was idling in a grid lock… got pretty close to the upper side of OK temp wise… might install an electric pusher fan for those events


Anyways, I digress… question to the gurus (which I know might be opening Pandora’s box) but I have a rebuilt Carter bbd… would there be any advantage to throwing on a 600cfm Holley? Engine is a 318 w/ 727 and 4 3/4 rear.

View attachment 1711816

Couple of good looking tree stumps in the foreground......
BOB RENTON

 

[1967coronet]

The 318 is a great small block engine.
Now ask it to tote that camper and what you pack in it. It will do the job.
Now stick a boat and trailer behind it.
That 318 will still rise to the challenge.
Now stick a mountain in front of it on a summer day.
Yep that 318 will still do the job but that sucker is going to start complaining.
2bbl, 4bbl it's not really going to matter outside of the fact you will get really good a tuning a holley if you swap.
Toss a electric fan and manual switch on it for the big hills . I would leave the 2bbl on and just take good care of the engine , tune ups ect.

 

[pjoll84]

The 318 is a great small block engine.
Now ask it to tote that camper and what you pack in it. It will do the job.
Now stick a boat and trailer behind it.
That 318 will still rise to the challenge.
Now stick a mountain in front of it on a summer day.
Yep that 318 will still do the job but that sucker is going to start complaining.
2bbl, 4bbl it's not really going to matter outside of the fact you will get really good a tuning a holley if you swap.
Toss an electric fan and manual switch on it for the big hills . I would leave the 2bbl on and just take good care of the engine , tune ups ect.

Thank you! I was very impressed (albeit nervous as all get out towing a boat… even if it’s “light”)… wasn’t expecting to fly up a mountain but was wondering if fuel delivery would improve the struggle… sounds like for the most part, I should stick with what is on it

As for the manual switch m/electric fan I think that’s the way to go it has the tranny cooler built in to the bottom of the radiator… would it be overkill to add an extra trans cooler?

 

[Runcharger]

No: An additional trans cooler would be a very good addition.

 

[MWbirdLOVER70]

I couldn’t agree more. Buddy owns a trans shop and have learned my share watching and talking with him on this issue and transmissions since 86

 

[pjoll84]

Should I route it so it goes through a stand-a-lone trans cooler and then into the lower rad or get rid of the lower rad routing altogether and leave it with a dedicated cooler strapped in front of the rad?

 

[Don Frelier]

Leave what you have and add the cooler on the return line to the transmission.

 

[Runcharger]

Agree: Add it to the return line after the rad cooler.