DragRaceResults.Com    Bracket Talk    Bracket Talk Forum  Hop To Forum Categories  Tech Talk - by Abruzzi    Vacum with Evac tubes
Go
New
Find
Notify
Tools
Reply
  
Vacum with Evac tubes
 Login/Join
 
DRR Pro
Picture of Eman
posted
A while back there was a discussion about vacum pumps and evac tbes. I had my car in the shop the other day and removed a hose from my valve cover breather and connected my Snap-on vacum gauge. While I could feel a little at idle it didn't show on the gauge but from 2,000 to 3,000 it was a steady 2in of vacum. My tubes are homemade black iron pipe nipples that I welded in the header collectors. I did cut a slot in the pipe and it is in the stream to help create a draw just like you would with a piece of hose using compressed air to start a siphon.
 
Posts: 1479 | Location: E TN | Registered: February 13, 2009Reply With QuoteReport This Post
DRR Trophy
posted Hide Post
Did some testing on that setup a few years back 355 in. motor single 4 pulled 7 inches at about 6500 down track i/8th mile


The difference between ignorance and stupidity. Ignorance is lack of knowledge. Stupidity is the inability to learn. Don't be stupid
 
Posts: 419 | Location: des moines iowa | Registered: January 10, 2020Reply With QuoteReport This Post
DRR Pro
posted Hide Post
^^^^^^^ That’s Amazing evac results imho. I have evac and think they work, but don’t own a gauge to verify.
 
Posts: 2500 | Location: 53056 | Registered: December 30, 2009Reply With QuoteReport This Post
DRR Pro
Picture of Eman
posted Hide Post
quote:
Originally posted by vetman:
Did some testing on that setup a few years back 355 in. motor single 4 pulled 7 inches at about 6500 down track i/8th mile

Is that measuring in the hose like I did or in the motor like others do with a pump and a sensor?
 
Posts: 1479 | Location: E TN | Registered: February 13, 2009Reply With QuoteReport This Post
DRR Trophy
posted Hide Post
Vacunm outlet in valve cover to gauge duct taped to cowl nothing fancy but good data


The difference between ignorance and stupidity. Ignorance is lack of knowledge. Stupidity is the inability to learn. Don't be stupid
 
Posts: 419 | Location: des moines iowa | Registered: January 10, 2020Reply With QuoteReport This Post
DRR Pro
Picture of SpeierRacingHeads
posted Hide Post
So I think a killer EVAC system is totally overlooked for classes or guys that simply don't want a vacuum pump. It's something I plan on trying. I have a few different ideas. It's worth the effort. A basic 5" was worth noticeable HP on the dyno with thin rings and totally sealed up.



 
Posts: 1405 | Location: Hays Kansas | Registered: January 23, 2006Reply With QuoteReport This Post
DRR Sportsman
Picture of FastLane
posted Hide Post
Chris, what are you using for a vacuum source?
 
Posts: 397 | Location: Parked... | Registered: May 27, 2007Reply With QuoteReport This Post



DRR Sportsman
Picture of sr4440
posted Hide Post
I had an SBC on the dyno that had evac tubes, well we capped them off, and left the breather to atmosphere, because my O2 sensors are located after the collectors. So after we were done, we hooked them up for the final pull of the day. I was shocked that the engine made 8hp more. This wasn't a maxed out engine, made somewhere around 450 -500hp


Without data, you’re just another guy with an opinion.
 
Posts: 1301 | Location: TEXAS | Registered: February 07, 2003Reply With QuoteReport This Post
DRR Pro
Picture of SpeierRacingHeads
posted Hide Post
quote:
Originally posted by FastLane:
Chris, what are you using for a vacuum source?


The tank is hooked to the manifold and one header collector and the other side of the tank to the breather. Then on the other header, breather to collector.
 
Posts: 1405 | Location: Hays Kansas | Registered: January 23, 2006Reply With QuoteReport This Post
DRR Top Comp
Picture of Curly1
posted Hide Post
quote:
Originally posted by vetman:
Did some testing on that setup a few years back 355 in. motor single 4 pulled 7 inches at about 6500 down track i/8th mile


I would have never thought you could get any where near 7 inches of vacuum with evac system. That is pretty good for sure.


https://postimg.cc/gallery/np3zpruo/
"Dunning-Kruger Effect"
-a type of Cognitive bias where people with little expertise or ability assume they have superior expertise or ability. This overestimation occurs as a result of the fact that they do not have enough knowledge to know they don't have enough knowledge.

Before you argue with someone ask yourself, "Is this person mentally mature enough to grasp the concept of a different perspective?" If not there is no point to argue.

4X NE2 CHAMPION. 2020 TDRA NE2 Champion
 
Posts: 4062 | Location: United States of Texas | Registered: April 02, 2011Reply With QuoteReport This Post
DRR S/Pro
posted Hide Post
I’m confused. But that’s easy!
Did I read You have a vac pump and breather to header tubes?


Raceless in California!
 
Posts: 4534 | Location: Vacaville  | Registered: January 07, 2004Reply With QuoteReport This Post
  Powered by Social Strata  
 

DragRaceResults.Com    Bracket Talk    Bracket Talk Forum  Hop To Forum Categories  Tech Talk - by Abruzzi    Vacum with Evac tubes

© DragRaceResults.com 2024