Help with picking out a carb for 5.9 magnum

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Bankjug

Bankjug

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I "think" I've picked out a good carb to use, but coming here to get second/more opinions just in case. I'm still learning as I go, so might need some patience! I'm going to be running:

-360 magnum bored 30 over
-9.5:1 compression I was told
-Edelbrock Performance RPM heads
-Edelbrock Performer RPM air-gap intake
-TTI headers
-3.23 gears
-I don't remember the cam specs, but definitely not stock. Something about 224/226 with 114 centerline or something like that?
-I'd use the cfm calculators, but I have no clue on my redline numbers. I've never had a tach in the car, so I've never known about my RPM. (I WILL be adding one with the new engine though)

Mostly street use, with some strip sightings for sure. I'm thinking of going with the Holley 670 Street Avenger. First time buying a new carb for a new engine, so just want to make sure I don't make a mistake with me choice. Thanks in advance!
 
AVS2 has been getting some good results. I never liked Holleys, Carters seemed to have better low end manners and smoother transitions. and they dont seem to stray from the initial tune.
 
Bankjug said:
I "think" I've picked out a good carb to use, but coming here to get second/more opinions just in case. I'm still learning as I go, so might need some patience! I'm going to be running:

-360 magnum bored 30 over
-9.5:1 compression I was told
-Edelbrock Performance RPM heads
-Edelbrock Performer RPM air-gap intake
-TTI headers
-3.23 gears
-I don't remember the cam specs, but definitely not stock. Something about 224/226 with 114 centerline or something like that?
-I'd use the cfm calculators, but I have no clue on my redline numbers. I've never had a tach in the car, so I've never known about my RPM. (I WILL be adding one with the new engine though)

Mostly street use, with some strip sightings for sure. I'm thinking of going with the Holley 670 Street Avenger. First time buying a new carb for a new engine, so just want to make sure I don't make a mistake with me choice. Thanks in advance!
Click to expand...
I have both the 670 street avenger and the 650 AVS2. Both work very well, but the AVS2 has a bit better throttle response due to the newer booster design. I will say that my current 360 engine has a stock cam. I have heard that the AVS2 is a little more difficult to tune with a hotter cam. You will get opinions on both sides.
 
625 street demon, most likely will work fine out of the box.
Street avengers seem to always be lean out of the box, I have one and do not care for it.
 
My 340 hated the 670SA I tried on it. Only way to make it work would've been to drill and tap the IFRs and do some serious tuning. Completely doable, but not really what I wanted to do with a brand new carb. I sold it and picked up a 750DP and couldn't be happier.
 
My build is similar. Stock bore 5.9 Magnum with new rings and bearings, Edelbrock 2.02 heads, Air Gap, Doug's headers. Cam is a Oregon Cam Grinding regrind of my core, .215/.223 @.050, .517 lift.

I started with a Edelbrock 750. Thing pulled really strong, but it would dump gas occasionally for no reason and foul the plugs. Bought a brand new AVS 650 and it has very crisp throttle response but I feel like the engine wants more and ran stronger with the 750.

I may rebuild the 750 and try it again. I like the simplicity of Edelbrock.

Good luck, half the fun is in experimenting!!!
 
i know the 625 street demon I had, is a very versitle carb.
It worked good on a stock 318 with nothing more than LD4B intake and stock exhaust.
Same carb I used on a 10.81 compression 5.9 mag with stock eldebrock heads, added headers and duel exhaust.
Simple carb adjustments and it ran good, same truck 4X4 W150 4-speed.

I liked the carb so much I bought another one for my 340 4-speed Duster, it cured the hot start issue I was having with the 700 Holley Double pumper.
 
The factory engineers were not dumb. Some 360s used 85o cfm carbs [ TQs ].
The Holley would make an excellent door stop...
Use an Edel carb. If mileage & general use is planned, the 650 AVS2 would be best.
For greater higher rpm performance, the 750 AFB or 800 AVS would be great.
 
ONLY ONE CARBURETOR!!!... LOL...
I've got two 625 Street demons on the duster... But I wouldn't recommend that..
I will be getting a 750 Street demon for my up coming small block truck build...
I have a costumer with a 750 street demon on a 400 GTO and it had the float bowls way out of adjustment out of the box... A simple adjustment and no problems.. actually it was good to take it apart as it gave him a greater understanding of how it works and how adjustments effect it.. also confidence to make adjustments...
Whatever carb you choose keep a log of factory settings and how it acted and every adjustment and how it acted and come back to this thread x-months from now and thank me you did...:thumbsup:...
 
j par said:
ONLY ONE CARBURETOR!!!... LOL...
I've got two 625 Street demons on the duster... But I wouldn't recommend that..
I will be getting a 750 Street demon for my up coming small block truck build...
I have a costumer with a 750 street demon on a 400 GTO and it had the float bowls way out of adjustment out of the box... A simple adjustment and no problems.. actually it was good to take it apart as it gave him a greater understanding of how it works and how adjustments effect it.. also confidence to make adjustments...
Whatever carb you choose keep a log of factory settings and how it acted and every adjustment and how it acted and come back to this thread x-months from now and thank me you did...:thumbsup:...
Click to expand...
Changing one thing at a time and keeping a log is a great idea. It's too easy to lose the rabbit when making lots of changes.
 
Bankjug said:
I "think" I've picked out a good carb to use, but coming here to get second/more opinions just in case. I'm still learning as I go, so might need some patience! I'm going to be running:

-360 magnum bored 30 over
-9.5:1 compression I was told
-Edelbrock Performance RPM heads
-Edelbrock Performer RPM air-gap intake
-TTI headers
-3.23 gears
-I don't remember the cam specs, but definitely not stock. Something about 224/226 with 114 centerline or something like that?
-I'd use the cfm calculators, but I have no clue on my redline numbers. I've never had a tach in the car, so I've never known about my RPM. (I WILL be adding one with the new engine though)

Mostly street use, with some strip sightings for sure. I'm thinking of going with the Holley 670 Street Avenger. First time buying a new carb for a new engine, so just want to make sure I don't make a mistake with me choice. Thanks in advance!
Click to expand...
At 360 cubes, if your mainly cruising the streets and not visiting the top end much, the smaller 650avs or a Holley Street Brawler would do fine. It will respond very well on the street. The larger 750 size would provide a little bit more power over the curve you’ll notice. It’s not huge, but you’ll notice. On the big end, it’s worth about 10hp.
Throttle response will be good. Not as snappy as the smaller carb which is more sensitive to throttle position changes.

Ether will be good. If you go to a 750, I’d use the Holley Street Brawler.
 
Fwiw a long time ago I swapped on a 650 dbl where a 750dbl was ..and then back to the 750.
The diff felt yes, a little snappier ...but after 3500-4000rpm the 750 let it pull wayyy harder.
In a stick car, the snap is crap compared to the midrange tq rolling in at 2000-3500 on the street..its a big diff.
 
Now there’s something.

Is this a automatic car?
 
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