Carb Studs or Carb Bolts?

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KOZ45

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While my carb is off getting rebuilt, I need to order a new gasket and some other items.........

Which is better and Why:

Carb mounting bolts or studs?
 
Studs. Figure out the exact lentgh you need Carb. spacer ect: Bolts can get tough because carb. gets in the way. You have to hold up carb and wind them in evenly.
 
Thanks for all the info, I appreciate it

The bolts that were previously used to mount the carb are 5/16-18 and the threads are 3/4" long

The thickness of the carb flange is 1/2" and the depth of the threads in to the manifold are 7/8"

SO, 1-3/8" total but thats max also with bottoming out the studs into the manfold

With carb mounting studs, are washers always used ontop of the carb flange?
 
KOZ45 said:
Thanks for all the info, I appreciate it

The bolts that were previously used to mount the carb are 5/16-18 and the threads are 3/4" long

The thickness of the carb flange is 1/2" and the depth of the threads in to the manifold are 7/8"

SO, 1-3/8" total but thats max also with bottoming out the studs into the manfold

With carb mounting studs, are washers always used ontop of the carb flange?
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I use a flat washer on the carb flange. You can use a lock washer or a toothed washer under the nut as well.
 
I do not have a spacer, just directly bolted on to the square open bore Weiand 7512
 
Mounting studs or bolts should never stretch on a carb as your only torquing them down 7-10 ft lbs, like finger tight and 1/4 turn. But as any bolt into AL, Id stud it (with anti seize) just to prevent the wear on the AL threads. Bolts as said require you to insert the bolts under the accelerator pump linkage and other obstacles and then lower carb onto intake while threading them. PITA when a stud is just sneak a nut under there and tighten.
 
I would like to order the studs ASAP........since my carb is almost done getting rebuilt

Can anyone verify if a 1-1/2" long stud kit will work?
 
check depth of intake bolt holes, thickness of carb flange and gaskets, and leave yourself enough thread for a nut. Not much more as a tall stud wont let you get a box end around it and may interfere with the carb.
 
the intake thread holes are 7/8" deep

The thickness of the carb flange is 1/2" thick

So that is 1-3/8" total but that's max also with bottoming out the studs into the manifold and without having any threads on top for the nuts and or washers
 
I use studs. Many brand name carb studs don't have very long threads on them, not enough to use all the threads in the intake. The black studs that Ace Hardware sells have nice long threads and is what I use.
 
You can usually find studs at the local hardware store to save a few bucks, grade 8
 
Mopar "H" bolts for me.

s-l640.jpg


Get Real Get Mopar !!!!
 
KOZ45 said:
the intake thread holes are 7/8" deep

The thickness of the carb flange is 1/2" thick

So that is 1-3/8" total but that's max also with bottoming out the studs into the manifold and without having any threads on top for the nuts and or washers
Click to expand...

1/2" threads into manifold (about 1.5 x dia. is recommended min. engagement)
1/16" carb gasket
1/2" carb flange
1/16" flat washer
5/16" nut thickness (I'd always use an esna nut here)
1/8" couple of threads extend above the nut
-------------------------------------------------
= 1 9/16" stud OAL

You can get by with the 1 1/2" length, or buy longer ones and screw them in further, or even cut them off. (If you can't find the standard esna nuts and are using the sometimes easier to find "heavy" ones, adjust the stud length accordingly).

Use the esna nuts, that way they don't need a nasty lock washer, but they still won't loosen up by themselves.
an365.jpg
 
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I've used both and it's never made any difference ~~ except studs do make it easier to mount the carb straight the first time. As Pishta said, you're not putting any real torque on them so stretching really is not an issue. And yes, a washer and a lock washer on the carb flanges IMHO.
Edit ~ or a "ny-lock" nut as mentioned above.
 
lilfontleroy said:
I've used both and it's never made any difference ~~ except studs do make it easier to mount the carb straight the first time. As Pishta said, you're not putting any real torque on them so stretching really is not an issue. And yes, a washer and a lock washer on the carb flanges IMHO.
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I have bought a lot of old Edelbrock manifolds. (LD4B and D4B's) If everybody used studs the carb and thermostat threads wouldn't be all stripped out. I recommend studs for any aluminum fastening unless it has steel inserts.
 
toolmanmike said:
I have bought a lot of old Edelbrock manifolds. (LD4B and D4B's) If everybody used studs the carb and thermostat threads wouldn't be all stripped out. I recommend studs for any aluminum fastening unless it has steel inserts.
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I just put heli-coils in everything aluminum when they are new. You'll note that Edelbrock, for one, puts heli-coils in all the threads in their aluminum heads. Working in the aircraft industry, I have noted that most threaded holes get heli-coils installed at the OEM (brand-new parts).
 
Always use studs in anything aluminum. That’s what an aftermarket intake is made of. Studs prevent thread damage to aluminum by avoiding removal of the studs. It’s wise to replace factory oem transmission pan bolts with studs for the same exact reason. Over years of maintaining a carb, transmission, etc. You can avoid ruining an intake or transmission by using studs. Studs also make engine or tranny pans easier to remove or install. If you like to keeps up on a cars maintenance, tweek, adjust things quite often if need be, you should use studs. Steel bolts will ruin vital aluminum parts. Simply by removing them and torquing then one too many times. You can jeopardize or ruin a transmission or intake this way.
 
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Thanks guys.........the carb spacer I bought today came with a stud kit
 
pearljam724 said:
Always use studs in anything aluminum... It’s wise to replace factory oem transmission pan bolts with studs for the same exact reason. Over years of maintaining a carb, transmission, etc. You can avoid ruining an intake or transmission by using studs.
Click to expand...

Agree 100%. I have cross threaded trans bolt pans more times than I care to admit, and I pulled all the threads out of a C4 pan hole while mounting a B&M shifter cable bracket. Ended up putting a long bolt and nut in it from the top and it always leaked.
 
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