Max Power 74 Report post Posted May 20, 2015 OK, maybe you guys can save me a bunch of time since many of you may have dealt with this. The attached pic is a vacuum block on the intake for my 351w based stroker. The vacuum is for the power brakes and transmission modulator. The damn thing gets in the way. I have had to modify the dual feed inlet for my Holley, and now I want to install an aftermarket throttle cable bracket (better than my bent factory 2v one) and that hits it as well. The thing is just in the way. What have you guys used in this location? My Holley has an unused vacuum feed in the front, so I could eliminate the smaller vacuum line to the tranny, the vacuum feed at the rear of the Holley feeds the PCV, so basically I would only need to feed the power brakes. Something much lower profile would be ideal. I know it is a 38" NPT fitting, so that is a start. Quote Share this post Link to post Share on other sites
buening 63 Report post Posted May 20, 2015 Have you consider using a brass 90 elbow and relocating the vacuum to the firewall tree like used on the 70 mustangs? See below Quote Share this post Link to post Share on other sites
buening 63 Report post Posted May 20, 2015 Otherwise, modify your current block and cut off the top nipple and drill/tap/plug it, then drill/tap a side port and install a nipple there. Not sure on fitting or vacuum hose sizes, but the below may also be an option: http://www.ebay.com/itm/Intake-Manifold-Chrome-Steel-Vacuum-T-Fitting-1-2-Thread-1-4-1-2-Nipple-/201331516270 Quote Share this post Link to post Share on other sites
Max Power 74 Report post Posted May 20, 2015 Have you consider using a brass 90 elbow and relocating the vacuum to the firewall tree like used on the 70 mustangs? See below I have thought of that. With only 2 feeds necessary (don't wanna mix PCV with the rest) that might be overkill, but if the elbow is low enough profile, is is an option. Otherwise, modify your current block and cut off the top nipple and drill/tap/plug it, then drill/tap a side port and install a nipple there. Not sure on fitting or vacuum hose sizes, but the below may also be an option: http://www.ebay.com/itm/Intake-Manifold-Chrome-Steel-Vacuum-T-Fitting-1-2-Thread-1-4-1-2-Nipple-/201331516270 Modifying current would be a PITA, especially given the number of fixtures out there, but I have seen a lot like the link you posted. problem is in 2D, it's difficult to see how much lower profile they really are. Quote Share this post Link to post Share on other sites
1969_Mach1 333 Report post Posted May 21, 2015 Edelbrock offers a low profile 90 degree fitting for that. Edelbrock manifolds are bad for the location of that fitting. The Weiand Stealth manifold for 351W motors doesn't have that issue. Quote Share this post Link to post Share on other sites
barnett468 418 Report post Posted May 21, 2015 . the lowest profile fitting in the world will only be around 3/16 lower than the flat portion on top of your existing one . . if that is still too high, you need a carb spacer . . you can get one as thin as 1/4 inch. Quote Share this post Link to post Share on other sites
Max Power 74 Report post Posted May 22, 2015 Yeah, seems like Edelbrock really wants you to run one of their carbs. Looking at pics online the the RPM Airgap for the 351w application, they don't have a vacuum fitting at all. Not sure what those people are doing for power brakes etc. Maybe running off the carb or using a spacer with a fitting, although hood clearance is already an issue with the Air Gap. My Carb has two 3/8's fittings, maybe I will re-plumb off of that. Quote Share this post Link to post Share on other sites
Max Power 74 Report post Posted May 31, 2015 Found a low profile solution on eBay. Quote Share this post Link to post Share on other sites
lanky 44 Report post Posted May 31, 2015 @Max: can you tell me where you found that ebay fitting? I am about to be running a performer rpm too (I think that's what I see you have) Thanks Quote Share this post Link to post Share on other sites
Max Power 74 Report post Posted May 31, 2015 http://www.ebay.com/itm/PSS-1042-Stainless-Steel-Two-1-8-NPT-Ports-Low-Profile-Vacuum-Fitting-3-8-NPT-/230364313545?hash=item35a2c877c9&vxp=mtr You can get any size 1/8th vacuum nipples for the two ports. Quote Share this post Link to post Share on other sites
