5.7l carburetor choices

[carlos515]

Ok , I ordered JEG vortec heads 514080 and aluminum intake 513002 for my 355 build. Block is a 92 5.7l marine cam 14097395 .
The cfm flow for my motor is 436cfm according to the calculator. That seems a little low.
I have seen the 1409 by Edelbrock recommended . What Holly would be good ?
My intake is a square bore dual plane.
My Rochester that I have has a divorced choke . I really do not want to go through the expense of upgrading it to electric choke and an adapter base .

Thanks,
Carlos

 

[Bondo]

Ayuh,...... The 1409 is a Great choice, it's what Merc uses, 'n will bolt to any manifold,....
Merc hasn't used a Holley since the '70s when they came on the old Ford motors,....

 

[Scott Danforth]

Volvo used 715 cfm holleys on the 275hp and 280hp 350s

 

[carlos515]

There is a Quick Fuel Technology M650 Carburetor that I can get here in Canada . Looks like a Holly ?

 

[Scott Danforth]

Quick Fuel is the low $ version of holley. However for a mercruiser install, I would do an edelbrock because the throttle brackets fit.

 

[Scott06]

For the Edelbrock carb -Merc part number 805359T is the throttle bracket. I was able to take the studs off my two bbl bracket swap them to the new bracket. Bracket also will mount slave solenoid and 50 amp breaker if yours is on your throttle bracket, nice clean install

here is a schematic has the stud and fastener sizes as well.http://www.marineengine.com/parts/mercruiser-sterndrive-parts/357-alpha-4v/1g400000-up/carburetor-and-throttle-linkage

 

[carlos515]

Thanks all.
I will go with the 1409.
Thanks Scott , I kept the throttle bracket from my old carb. No the slave and breaker are on the water separator bracket.

Carlos

 

[carlos515]

Well....I researched the Rochester carbs. They are quite impressive that they come 750cfm and 800cfm , Just the tuning is different for different applications.
Long story short....I flip flopped the idea back and forth between the 1409 and rebuilding my Quadrajet. I ended up ordering a custom built electric choke from Carb Junky's , I had the rebuild kit already.
My carb is a 17080565 . But the jets are .70 and main rods are 42 .
The secondary rods are DE not CL.
My build is a 5.7l with vortec heads and aftermarket intake. Stock cam.
The manual states that the 5.0l and the 5.7l use .69 main jets and 42 rods.
Would I need to change my main jets to .69 and my secondary rods to CL ?
Or just leave them as is.
The carb is is good shape with very little play in the throttle shafts.
thanks,
Carlos

 

[achris]

.... What Holly would be good ?...

In a boat? None. Stay with the 1409.

 

[Lou C]

Well....I researched the Rochester carbs. They are quite impressive that they come 750cfm and 800cfm , Just the tuning is different for different applications.
Long story short....I flip flopped the idea back and forth between the 1409 and rebuilding my Quadrajet. I ended up ordering a custom built electric choke from Carb Junky's , I had the rebuild kit already.
My carb is a 17080565 . But the jets are .70 and main rods are 42 .
The secondary rods are DE not CL.
My build is a 5.7l with vortec heads and aftermarket intake. Stock cam.
The manual states that the 5.0l and the 5.7l use .69 main jets and 42 rods.
Would I need to change my main jets to .69 and my secondary rods to CL ?
Or just leave them as is.
The carb is is good shape with very little play in the throttle shafts.
thanks,
Carlos

For Quadrajet tuning questions try asking on Cliffs High Performance Quadrajets…if your original QJet is in good shape it can work just fine they were used on everything from a 4.3 to a 7.4 due to the flexibility built into the original design.

PS right now you can’t even get new Edelbrock 1409s last time I looked they have been on back order for a long time. Holley is available though; I would stick with the QJet. If in good shape it’s a great carb.

 

[carlos515]

Thanks Lou,
Ya only the rebuilt 9909 is available right now . Which is the 1409. And for a fraction of the cost I can rebuild my QJet. I will check out Cliffs .

Carlos

 

[Scott06]

Thanks Lou,
Ya only the rebuilt 9909 is available right now . Which is the 1409. And for a fraction of the cost I can rebuild my QJet. I will check out Cliffs .

Carlos

Cliff can probably best give you direction on your jetting questions as well.