Vacuum pump help

pmrphil · 07-23-2012, 10:45 PM

The Fel-Pro seal is the viton one, it's quite a bit stiffer than the normal silicone seal and should be installed in the normal fashion - I think the number is 2902, but double check to make sure.

Tom Goldman · 07-23-2012, 11:11 PM

Chuck's got it right.
Leave the trick stuff to the COMP racers.
I've run a vacuum pump for over 16 years and never had any problems pulling 15-16 " vacuum when all the other leak points are sealed up.
Fuel pump block off plates, distributer gaskets , manifold corners are prime leak culprits.
If your engine previously had minor oil leaks,don't expect to pull much vacuum .
HP gains are relative to ring packages ,end gaps and bore condition .

HR9121 · 07-23-2012, 11:12 PM

Rick I really didn't clarify that I haven't installed the vac pump yet I was actually going to in hopes that it may help me with my problem. I'm not really trying to gain hp just trying to help with some little leaks that are commonly associated with these high compression stroker motors. I appreciate everyones input and suggestions. Another question that comes to mind after reading Chuck's post is if you get too high of a vacuum could you run into some lubrication problems, possibly pushing oil away from the pick up. This is a wet sump application.

Bill Baer · 07-29-2012, 11:18 AM

Cooter

The guys I know who have had wrist pin problems are spinning the vacuumn pump faster than 1/2 crank speed and using dry sump systems in some cases they need to disconnect the pump during warm up.
They also with wet sumps see a reduction in oil pressure due to the reduced inlet pump pressure.
I have had no such problems.
Putting a vacuumn pump will reduce and or elimate almost all of your oil leaks, however the vent on the oil breather tank will mist a little oil when the oil is hot, it's no much but to me it's a little annoying.
I too use the felpo crank seal.

HR9121 · 07-31-2012, 04:05 PM

Thanks Bill for the info, very helpful now if I can just get time to install it.

THE LEGEND · 08-21-2012, 08:27 AM

Coot,
Have you thought about installing a pcv valve on both sides. We were doing that with Stocker motors a few years ago.

nhra686 · 04-10-2013, 09:51 AM

We run regular seals and pull 12-15" of vacuum with no problem.

voltdr · 04-11-2013, 10:28 PM

I run about 14.2" at the finish line. I run the crank seal in the normal direction. No leaks, no issues. As stated earlier, the vac pump will help cure most oil drips and oozings.

07-23-2012, 10:45 PM	#1
pmrphil Member Join Date: Aug 2010 Location: CT Posts: 454 Likes: 1,780 Liked 345 Times in 149 Posts	Re: Vacuum pump help The Fel-Pro seal is the viton one, it's quite a bit stiffer than the normal silicone seal and should be installed in the normal fashion - I think the number is 2902, but double check to make sure. __________________ Phil Molski PMR Performance S/C 1623

07-23-2012, 11:11 PM	#2
Tom Goldman VIP Member Join Date: Jan 2003 Location: Allentown,PA Posts: 2,473 Likes: 881 Liked 858 Times in 234 Posts	Re: Vacuum pump help Chuck's got it right. Leave the trick stuff to the COMP racers. I've run a vacuum pump for over 16 years and never had any problems pulling 15-16 " vacuum when all the other leak points are sealed up. Fuel pump block off plates, distributer gaskets , manifold corners are prime leak culprits. If your engine previously had minor oil leaks,don't expect to pull much vacuum . HP gains are relative to ring packages ,end gaps and bore condition . __________________ Tom Goldman 1500 SG , 1506 STK

07-23-2012, 11:12 PM	#3
HR9121 Live Reporter Join Date: Jan 2011 Location: New Bern, NC Posts: 3,467 Likes: 146 Liked 3,363 Times in 731 Posts	Re: Vacuum pump help Rick I really didn't clarify that I haven't installed the vac pump yet I was actually going to in hopes that it may help me with my problem. I'm not really trying to gain hp just trying to help with some little leaks that are commonly associated with these high compression stroker motors. I appreciate everyones input and suggestions. Another question that comes to mind after reading Chuck's post is if you get too high of a vacuum could you run into some lubrication problems, possibly pushing oil away from the pick up. This is a wet sump application. __________________ James Williamson W200 J/SA. SS/JA

07-29-2012, 11:18 AM	#4
Bill Baer Senior Member Join Date: Jul 2007 Location: Nothern IL Posts: 596 Likes: 1 Liked 1 Time in 1 Post	Re: Vacuum pump help Cooter The guys I know who have had wrist pin problems are spinning the vacuumn pump faster than 1/2 crank speed and using dry sump systems in some cases they need to disconnect the pump during warm up. They also with wet sumps see a reduction in oil pressure due to the reduced inlet pump pressure. I have had no such problems. Putting a vacuumn pump will reduce and or elimate almost all of your oil leaks, however the vent on the oil breather tank will mist a little oil when the oil is hot, it's no much but to me it's a little annoying. I too use the felpo crank seal. __________________ Bill Baer 3391 SC, 339B SC, QR Last edited by Bill Baer; 07-29-2012 at 11:20 AM.

07-31-2012, 04:05 PM	#5
HR9121 Live Reporter Join Date: Jan 2011 Location: New Bern, NC Posts: 3,467 Likes: 146 Liked 3,363 Times in 731 Posts	Re: Vacuum pump help Thanks Bill for the info, very helpful now if I can just get time to install it. __________________ James Williamson W200 J/SA. SS/JA

08-21-2012, 08:27 AM	#6
THE LEGEND VIP Member Join Date: Aug 2002 Location: Fayetteville, n.c. Posts: 1,411 Likes: 0 Liked 1 Time in 1 Post	Re: Vacuum pump help Coot, Have you thought about installing a pcv valve on both sides. We were doing that with Stocker motors a few years ago.

04-10-2013, 09:51 AM	#7
nhra686 Junior Member Join Date: Apr 2013 Location: Northern California Posts: 1 Likes: 0 Liked 0 Times in 0 Posts	Re: Vacuum pump help We run regular seals and pull 12-15" of vacuum with no problem. __________________ Bill Huntington S/C, S/G, T/D, S/Pro

04-11-2013, 10:28 PM	#8
voltdr Senior Member Join Date: Jan 2008 Location: Texas Posts: 705 Likes: 77 Liked 97 Times in 50 Posts	Re: Vacuum pump help I run about 14.2" at the finish line. I run the crank seal in the normal direction. No leaks, no issues. As stated earlier, the vac pump will help cure most oil drips and oozings.