C2 427 carburetor mounting

[Robert T.]

[Kent D.]

Re: C2 427 carburetor mounting

I just put a new Holley carb on my '66 427 390 hp and did not have a problem with the studs. You might try unscrewing the studs a few turns so you have more threads on the top for the nut. You can also go to your local auto parts store and buy longer studs.

[Joe L.]

Re: C2 427 carburetor mounting

Bob-----

The thickness of the throttle body at the corner flanges should be just about 15/32".

[Richard F.]

Re: C2 427 carburetor mounting

I had a similar problem with an original Holley 4150 when I ordered new studs from LICC. They would just barely work, except for the corner where the throttle bracket fits. The stud didn't even come all the way through the nut. So I ordered from Jegs, where you have a choice of two or three lengths. The LICC studs are now on my clutch fan, because I didn't like that the original clutch fan used bolts.

[Geoff C.]

Beware

Your carb studs may not be, and probably are not the same tensile strength as those required for a fan clutch, particularly when from FLAPS in a skin pak printed hencho en China. Those Corvettes that originally do use studs for the fan clutch are a stronger grade than carb studs. Can you visualize a fan and clutch at 6500 RPM sailing through whatever is near? It's bad enough when you break a motor mount.

Geoffrey Coenen

PS I do not recommend using their toothpaste or pet food either.

[Robert T.]

Re: C2 427 carburetor mounting

Thanks for the quick responses from everyone and for the measurement number. I think I'll back the studs out a little to see if that will do it. For some strange reason when I installed them I just ran them all the way in. Probably didn't need to do that.

Thanks again for the help,

Bob

[Richard F.]

Re: Beware

Thanks, Geoffrey. I'm glad we had this little chat. I guess it stands to reason that if I'd used the studs for the carb mounting, I wouldn't want to lift the motor that way!

[Geoff C.]

Re: Beware

Actually some do lift a motor that way. But there is difference due to the difference in the way the force is applied. A very fast spinning mass has a different dynamic load than a rather static loading, but I'm not a rocket scientist, anymore or ever was.
But I do know those studs used on a fan clutch are a higher grade than carb studs.

Geoffrey Coenen

PS Is it Mass x Velocity = Force or some such scientific blather? I CRS.

a one pound fan at 6500 RPM is much more forceful than a 1000 pound motor and trans hoisted at 1 foot per minute or is my physics completely forgotten?

[Robert M.]

Re: Beware

I believe it's Force = Mass x Acceleration.

[Chuck R.]

Re: Also beware Bob

By backing the studs out to accomodate the nuts, now the studs are not bottomed out in the manifold and may want to back out due to heat, vibration or both.

If your set on using these studs, make sure you at least add a fair amount of blue Loctite to the stud ends going into the manifold.

Chuck

[Jack H.]

Newton's Impulse Momentum Theory...FT=MV *NM*

[Chuck S.]

What I Was Thinking...

If it were me, I would get longer studs instead...I can't abide potentially unstable situations that require constant nagging doubt.

It's hard for me to believe Chevy would have engineered it like that. Perhaps the repro stud length is just one of those one-size-fits-all "misunderstandings".

[Chuck R.]

Re: What I Was Thinking Too

Especially if the intake is freshly painted.

The potential for fuel and vacuum leaks would do it for me.

Chuck