Corvair DiagramCorvair Photo
Corvair Center
home forum corvairs calendar links Corvair Podcast
California Corvairs
Clarks Corvair
Clarks Corvair
“CORSA"



Chevy Corvair License Plate
Chevy Corvair Chrome Wheel
Corvair Center Forum :  Corvair Center Phorum The fastest message board... ever.
Corvair Center 
Large Carb Stud hole? WHY?
Posted by: beenzo2since71 ()
Date: February 12, 2018 10:17AM

I have always wondered why did gm have a larger hole in the head for the carb stud , for warmup ??? al



Edited 1 time(s). Last edit at 02/12/2018 10:28AM by MattNall.

Options: ReplyQuote
Re: Large Carb Stud hole? WHY?
Posted by: Melb-Mike ()
Date: February 12, 2018 03:37PM

I think you're referring to the sunken pocket of the longer carb stud. I used to think it was to allow the stud to flex a bit to allow a smooth installation of the carb in case of slight misalignment....but that is just a guess on my part.

64 Greenbrier
64 Spyder (needs restoration)
65 Corsa 140, restored
66 Corsa turbo, restoring now
66 Corsa 140 "RR" code coupe fully restored
67 Pontiac GTO restored
69 Corvette 427 convertible restored
2015 Porsche Panamera S
2015 Corvette Z06
1965 AC Cobra (Factory Five)

Options: ReplyQuote
Re: Large Carb Stud hole? WHY?
Posted by: Dan ()
Date: February 13, 2018 12:31PM

Maybe to reduce heat transfer to th carb to lessen vapor lock?

Dan
Chandler, AZ
1966 Corsa Turbo Convertible
[corvaircenter.com]

Options: ReplyQuote
Re: Large Carb Stud hole? WHY?
Posted by: MattNall ()
Date: February 13, 2018 12:47PM

I'm thinking thermal expansion rates?





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

Options: ReplyQuote
Re: Large Carb Stud hole? WHY?
Posted by: tknobby ()
Date: February 13, 2018 02:05PM

That hole is actually cast in. That was required during the casting to reduce the volume of the aluminum. If the volume is too great in one spot then as the alloy is cooling that thick volume will shrink and try to draw aluminum from surrounding areas. If the surrounding areas have cooled and solidified (which they would) then the casting would have a void or porosity. By adding that pocket the engineers minimized the chance of porosity.

T...

Tom Knoblauch
San Antonio, TX
AmericanFlat6.com

'64 Spyder Vert Big Valve heads, EFI, Custom roller cam, front disc brakes on 2" dropped spindles
'65 Vert 95 EFI 4spd
'65 Monza Coupe 95 w/ Thomas Tribute 110 heads, 2 2bbl 40MM Webers, 140 exh tubes, 110 exh logs, PG w/ high stall Converter, 2" dropped spindles w/ 6 piston Wilwood calipers
'66 Monza Coupe 3.0L EFI 4spd
'68 Monza Coupe 140 3.0L EFI Slide Throttle 4spd
'63 Rampy 80hp w/ 102 Tribute 2 carb heads 4 spd, disc brakes on 2" dropped spindles

Options: ReplyQuote
Re: Large Carb Stud hole? WHY?
Posted by: MattNall ()
Date: February 13, 2018 04:06PM

AHH the Master speaks!!! Thanks!





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

Options: ReplyQuote


Sorry, only registered users may post in this forum.
This forum powered by Phorum.