Q Jet questions

BWill · 06-30-2015, 10:41 AM

How far should the sec. throttle plates open on a stock GM intake?, and how far on an open plenum intake. I know there is a measurement for the sec. air valve door opening, anybody have that number?, thanks

tj310 · 07-02-2015, 11:46 AM

Throttle plate 90* +or - 5
Air valve most look like like they should open a little more .
When I did test carbs back to back I didn't find any topend gain.
---Trevor

Jim Hanig · 07-02-2015, 03:28 PM

I spent days fooling with it on the dyno never found anything unless u got it way out .Then it hurt the power.

Bob Mulry · 07-03-2015, 09:32 PM

Hard to test a Q-Jet on a dyno because most of them don't have wheels...

Bob

Jim Hanig · 07-07-2015, 08:28 AM

Evan harder if you race track is a 100 miles away.

Dan Fahey · 07-07-2015, 11:08 AM

Quote:

Originally Posted by Bob Mulry

Hard to test a Q-Jet on a dyno because most of them don't have wheels...

Bob

You mean the Flintstone Dyno Test !!

Bob Mulry · 07-09-2015, 05:14 PM

Quote:

Originally Posted by Jim Hanig

Evan harder if you race track is a 100 miles away.

Only a hundred miles away...........

That's like having a Drag Strip in your back yard......

Bob

JRyan · 07-09-2015, 07:36 PM

Bob,

Jim is used to having one in his back yard (Houston). Now back in SoDak, that's no longer the case.

Jerry

Monte Howard · 07-11-2015, 10:36 AM

Secondary air door, 1.280 - 1.320 from the back of the air horn to top of secondary air door.

06-30-2015, 10:41 AM	#1
BWill Junior Member Join Date: Apr 2012 Posts: 13 Likes: 0 Liked 0 Times in 0 Posts	Q Jet questions How far should the sec. throttle plates open on a stock GM intake?, and how far on an open plenum intake. I know there is a measurement for the sec. air valve door opening, anybody have that number?, thanks

07-02-2015, 11:46 AM	#2
tj310 Member Join Date: Sep 2009 Location: Dresden On. Canada Posts: 460 Likes: 0 Liked 0 Times in 0 Posts	Re: Q Jet questions Throttle plate 90* +or - 5 Air valve most look like like they should open a little more . When I did test carbs back to back I didn't find any topend gain. ---Trevor

07-02-2015, 03:28 PM	#3
Jim Hanig Senior Member Join Date: Aug 2006 Location: Pukwana SD Posts: 858 Likes: 555 Liked 97 Times in 47 Posts	Re: Q Jet questions I spent days fooling with it on the dyno never found anything unless u got it way out .Then it hurt the power.

07-03-2015, 09:32 PM	#4
Bob Mulry VIP Member Join Date: Apr 2002 Location: Coarsegold, CA Posts: 1,017 Likes: 57 Liked 321 Times in 101 Posts	Re: Q Jet questions Hard to test a Q-Jet on a dyno because most of them don't have wheels... Bob __________________ Bob Mulry 7516 STK A & M Motorsports

07-07-2015, 08:28 AM	#5
Jim Hanig Senior Member Join Date: Aug 2006 Location: Pukwana SD Posts: 858 Likes: 555 Liked 97 Times in 47 Posts	Re: Q Jet questions Evan harder if you race track is a 100 miles away.

07-09-2015, 07:36 PM	#8
JRyan Senior Member Join Date: Apr 2003 Location: Aberdeen SD Posts: 642 Likes: 28 Liked 104 Times in 28 Posts	Re: Q Jet questions Bob, Jim is used to having one in his back yard (Houston). Now back in SoDak, that's no longer the case. Jerry

07-11-2015, 10:36 AM	#9
Monte Howard Member Join Date: Nov 2002 Location: Potomac,IL Posts: 268 Likes: 1 Liked 48 Times in 14 Posts	Re: Q Jet questions Secondary air door, 1.280 - 1.320 from the back of the air horn to top of secondary air door. __________________ Monte Howard 3209 STK, 3208 SS