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WIDE OPEN VACUUM TEST...................... #1595247 03/19/14 01:50 AM 03/19/14 01:50 AM
Joined: Jul 2004 Posts: 19,317 State of confusion T Thumperdart OP I Live Here
Thumperdart OP I Live Here T Joined: Jul 2004 Posts: 19,317 State of confusion	How many of you folks have done a dyno or street wide open test to see how much vacuum you have? After much thinking and research I`m thinking my 3.5 p/v COULD be closing at wot if I`m pullin more that a few inches of vacuum............Anyone? 72 Dart 470 n/a BB stroker street car `THUMPER`...Check me out on FB Dominic Thumper for videos and lots of carb pics......760-900-3895.....

Re: WIDE OPEN VACUUM TEST...................... [Re: Thumperdart] #1595248 03/19/14 02:35 AM 03/19/14 02:35 AM
Joined: May 2003 Posts: 902 Gilbert, AZ A Aspen7695 super stock
Aspen7695 super stock A Joined: May 2003 Posts: 902 Gilbert, AZ	I run a TQuad on my stocker. At WOT I have zero vacuum. Raul

Re: WIDE OPEN VACUUM TEST...................... [Re: Aspen7695] #1595249 03/19/14 03:20 AM 03/19/14 03:20 AM
Joined: Jul 2004 Posts: 19,317 State of confusion T Thumperdart OP I Live Here
Thumperdart OP I Live Here T Joined: Jul 2004 Posts: 19,317 State of confusion	Quote: I run a TQuad on my stocker. At WOT I have zero vacuum. Raul Is that wot in high gear wooded? 72 Dart 470 n/a BB stroker street car `THUMPER`...Check me out on FB Dominic Thumper for videos and lots of carb pics......760-900-3895.....

Re: WIDE OPEN VACUUM TEST...................... [Re: Thumperdart] #1595250 03/19/14 04:00 AM 03/19/14 04:00 AM
Joined: Aug 2003 Posts: 43,200 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,200 Bend,OR USA	Put a vacume gauge in the car where you can see it easily and go for a ride Probally not going to see any vacume with yoour parts, 1050 Dominator and so on What does the wide ban say Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: WIDE OPEN VACUUM TEST...................... [Re: Cab_Burge] #1595251 03/19/14 10:43 AM 03/19/14 10:43 AM
Joined: Jan 2007 Posts: 8,041 Mt Morris Michigan mopar dave master
mopar dave master Joined: Jan 2007 Posts: 8,041 Mt Morris Michigan	with my 408 and a 950 I have 1.5-2"@wot. that's why I decided to try a dominator this year. http://www.youtube.com/watch?v=aIxaesJ190U http://youtu.be/lCZAaN7fFLg

Re: WIDE OPEN VACUUM TEST...................... [Re: Thumperdart] #1595252 03/19/14 11:50 AM 03/19/14 11:50 AM
Joined: Oct 2003 Posts: 7,506 Az Crizila master
Crizila master Joined: Oct 2003 Posts: 7,506 Az	Quote: How many of you folks have done a dyno or street wide open test to see how much vacuum you have? After much thinking and research I`m thinking my 3.5 p/v COULD be closing at wot if I`m pullin more that a few inches of vacuum............Anyone? Any vacuum basically sez restriction. I know some who do carb sizing that way. Through the lights, you wanna see no more than 1.5" for a race only application. Fastest 300

Re: WIDE OPEN VACUUM TEST...................... [Re: Crizila] #1595253 03/19/14 11:59 AM 03/19/14 11:59 AM
Joined: May 2011 Posts: 4,489 northern,Ohio,USA C Clanton master
Clanton master C Joined: May 2011 Posts: 4,489 northern,Ohio,USA	Here is some good posts about it. https://www.google.com/url?sa=t&rct=...JMNmT-xav9BPH2g GOTBOOST!New improved with Victor heads. http://www.enginelabs.com/mopar-big-bloc...t-of-necessity/

Re: WIDE OPEN VACUUM TEST...................... [Re: Thumperdart] #1595254 03/19/14 12:06 PM 03/19/14 12:06 PM
Joined: Jan 2003 Posts: 10,007 Frostbitefalls MN (Rocky&Bullw... gregsdart I Live Here
gregsdart I Live Here Joined: Jan 2003 Posts: 10,007 Frostbitefalls MN (Rocky&Bullw...	At 7,000 rpm and 100 percent VE, you pull 950 cfm with 470 cubes. Your VE may be over that, but not by much. I would think the pv would be plenty high, and your WOT vacuum will be 1.6 or less. Probably the only real test would be a AFR test to see what is going on. You could also put a new 4.5 in it and test it. Last edited by gregsdart; 03/19/14 12:16 PM.

Re: WIDE OPEN VACUUM TEST...................... [Re: gregsdart] #1595255 03/19/14 01:35 PM 03/19/14 01:35 PM
Joined: Jul 2004 Posts: 19,317 State of confusion T Thumperdart OP I Live Here
Thumperdart OP I Live Here T Joined: Jul 2004 Posts: 19,317 State of confusion	Will install a vac gauge soon and test these things but I can`t get my wot rich enuff w/out jetting it to the moon so was just curious. I`ll get some 26 hsb`s also and go from there. Right now I`m bet. 12.8-13.2 at wot and VP likes to see low 12`s w/their now 101 unleaded. 72 Dart 470 n/a BB stroker street car `THUMPER`...Check me out on FB Dominic Thumper for videos and lots of carb pics......760-900-3895.....

Re: WIDE OPEN VACUUM TEST...................... [Re: Thumperdart] #1595256 03/19/14 01:53 PM 03/19/14 01:53 PM
Joined: Nov 2004 Posts: 2,495 Oregon City, OR Baxter61 top fuel
Baxter61 top fuel Joined: Nov 2004 Posts: 2,495 Oregon City, OR	Try sticking a plug in it and jetting up till your fat enough and record the jet number. Figure out the difference flow of your current primary jets and what its jets it took without the pv. That's how much your power valve channels need to flow.

Re: WIDE OPEN VACUUM TEST...................... [Re: Baxter61] #1595257 03/19/14 01:57 PM 03/19/14 01:57 PM
Joined: Jul 2004 Posts: 19,317 State of confusion T Thumperdart OP I Live Here
Thumperdart OP I Live Here T Joined: Jul 2004 Posts: 19,317 State of confusion	I tried that years ago before the wide band and just may again it`s just a pain testing on the street at 120+ mph............ 72 Dart 470 n/a BB stroker street car `THUMPER`...Check me out on FB Dominic Thumper for videos and lots of carb pics......760-900-3895.....

Re: WIDE OPEN VACUUM TEST...................... [Re: Thumperdart] #1595258 03/19/14 01:59 PM 03/19/14 01:59 PM
Joined: Jun 2008 Posts: 3,916 usa L lewtot184 master
lewtot184 master L Joined: Jun 2008 Posts: 3,916 usa	Quote: How many of you folks have done a dyno or street wide open test to see how much vacuum you have? After much thinking and research I`m thinking my 3.5 p/v COULD be closing at wot if I`m pullin more that a few inches of vacuum............Anyone? if your pulling over 3.5" of vacuum at WOT you've got issues. 3.5" would indicate a very big restriction on the intake/carb. i'd look for fuel delivery problems.

Re: WIDE OPEN VACUUM TEST...................... [Re: lewtot184] #1595259 03/19/14 02:15 PM 03/19/14 02:15 PM
Joined: Jul 2004 Posts: 19,317 State of confusion T Thumperdart OP I Live Here
Thumperdart OP I Live Here T Joined: Jul 2004 Posts: 19,317 State of confusion	I personally don`t see it pullin that much and it was a suggestion to check it out but I leave no stone unturned and will VERIFY everything before I hit the track here soon........... 72 Dart 470 n/a BB stroker street car `THUMPER`...Check me out on FB Dominic Thumper for videos and lots of carb pics......760-900-3895.....

Re: WIDE OPEN VACUUM TEST...................... [Re: Thumperdart] #1595260 03/19/14 02:53 PM 03/19/14 02:53 PM
Joined: Nov 2004 Posts: 2,495 Oregon City, OR Baxter61 top fuel
Baxter61 top fuel Joined: Nov 2004 Posts: 2,495 Oregon City, OR	Quote: I tried that years ago before the wide band and just may again it`s just a pain testing on the street at 120+ mph............ need a co-pilot?

Re: WIDE OPEN VACUUM TEST...................... [Re: Baxter61] #1595261 03/19/14 03:23 PM 03/19/14 03:23 PM
Joined: Jul 2004 Posts: 19,317 State of confusion T Thumperdart OP I Live Here
Thumperdart OP I Live Here T Joined: Jul 2004 Posts: 19,317 State of confusion	Quote: Quote: I tried that years ago before the wide band and just may again it`s just a pain testing on the street at 120+ mph............ need a co-pilot? Come on............. 72 Dart 470 n/a BB stroker street car `THUMPER`...Check me out on FB Dominic Thumper for videos and lots of carb pics......760-900-3895.....

Re: WIDE OPEN VACUUM TEST...................... [Re: Thumperdart] #1595262 03/23/14 10:42 AM 03/23/14 10:42 AM
Joined: May 2003 Posts: 902 Gilbert, AZ A Aspen7695 super stock
Aspen7695 super stock A Joined: May 2003 Posts: 902 Gilbert, AZ	Sorry it took so long to reply. I was racing at Las Vegas.. I have zero vacuum at WOT all the way down the track. Raul

Re: WIDE OPEN VACUUM TEST...................... [Re: Aspen7695] #1595263 03/23/14 10:48 PM 03/23/14 10:48 PM
Joined: Jun 2003 Posts: 9,225 Charleston S sixpackgut Drag Week Mod Champion
sixpackgut Drag Week Mod Champion S Joined: Jun 2003 Posts: 9,225 Charleston	I never use a PV lower than 6.5 except in the borrowed carb i used for drag week last year and i believe that was happening to me but it was actually helping. There is no reason to have a 3.5 PV in a carb. Do not listen to anyone that tells you to use a PV that is 2" lower. That is complete nonsense Gen 3 power 6.22@110, 9.85@135 Follow @g3hemiswap on instagram performance only racing, CRT, ultimate converter, superior design concepts, ThumperCarbs

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