Preludedude Posted October 2, 2015 Report Share Posted October 2, 2015 Trying to install my mechanical fuel pressure gauge today, and its a summit 1" fuel pressure gauge...water filled.. It has a small screw inside where the 1/8NPT threads are... When backed out, this is as far as it will go....but it will thread into the gauge about 1/4'... Am I supposed to screw this in so the fuel has a way to get to the gauge? Ive never used a mechanical gauge before...I may be dumb but Im checking before I install this thing... http://i1221.photobucket.com/albums/dd461/Preludedude1/photo.jpg Link to comment Share on other sites More sharing options...
ucw458 Posted October 2, 2015 Report Share Posted October 2, 2015 Does the screw move the needle like a zero adjustment screw? Link to comment Share on other sites More sharing options...
Preludedude Posted October 2, 2015 Author Report Share Posted October 2, 2015 No. It threads in and out easily. Needle doesn't move. Link to comment Share on other sites More sharing options...
scott87star Posted October 2, 2015 Report Share Posted October 2, 2015 I'd say a flow restrictor, just in case.... Link to comment Share on other sites More sharing options...
87redcat Posted October 2, 2015 Report Share Posted October 2, 2015 no paperwork with it explaining the purpose??? weird Link to comment Share on other sites More sharing options...
Preludedude Posted October 2, 2015 Author Report Share Posted October 2, 2015 Nope. Bought from summit off eBay. Link to comment Share on other sites More sharing options...
speedyquest Posted October 2, 2015 Report Share Posted October 2, 2015 Time to cross reference the numbers for it, find the manufacturer, then read their instructions on the website. That of course assumes all those are available lol. Link to comment Share on other sites More sharing options...
Preludedude Posted October 3, 2015 Author Report Share Posted October 3, 2015 (edited) Cant find anything...guess ill install it and see if needle moves with that screw in place...i just dont see how fuel pushing on that screw will make needle move...the screw is threaded, so i dunno...we will see... What is stock fuel pressure supposed to be? And what should I turn it up to? I have 650/950, big 16G, 52mm TB, forged wiseco's, etc..... Edited October 3, 2015 by Preludedude Link to comment Share on other sites More sharing options...
Edde Posted October 3, 2015 Report Share Posted October 3, 2015 35-38 at idle. Link to comment Share on other sites More sharing options...
Preludedude Posted October 3, 2015 Author Report Share Posted October 3, 2015 Update. Removed the screw and the threads have a tiny slit down them for fuel to run down to get to needle. There are 3 slits in the screw all together. So fuel can get by the screw. Link to comment Share on other sites More sharing options...
Edde Posted October 3, 2015 Report Share Posted October 3, 2015 So the screw is to prevent junk from getting in? Link to comment Share on other sites More sharing options...
Preludedude Posted October 3, 2015 Author Report Share Posted October 3, 2015 Possibly. I can't find instructions or installation directions anywhere.......why it screws up and down I don't know. But fuel can get by is all I know. Maybe it's for high and low pressure applications. The depth of screw needs to be changed with the application I guess Link to comment Share on other sites More sharing options...
Edde Posted October 4, 2015 Report Share Posted October 4, 2015 Oh then it's likely for metering somehow. I misread before. Link to comment Share on other sites More sharing options...
Preludedude Posted October 6, 2015 Author Report Share Posted October 6, 2015 Installed today....I set the fuel pressure to 38psi at idle...All is well so far with the Spa Turbo AFPR and Summit gauge....I left the screw flush and not screwed down inside the threads, but its good and fuel can get by the screw because of the tiny slits in the threads... Hope this helps someone in the future.... Link to comment Share on other sites More sharing options...
mstieg Posted October 24, 2015 Report Share Posted October 24, 2015 Does the screw set the base pressure? That's how it works with my MSD 2222. There's a nipple on it for the rising rate 1:1 signal which might also be an option for yours?? A screw or bolt will disable the rising rate however. Link to comment Share on other sites More sharing options...
importwarrior Posted October 25, 2015 Report Share Posted October 25, 2015 Probably for calibration and or how they filled it with the oil inside ??? Link to comment Share on other sites More sharing options...
Preludedude Posted October 25, 2015 Author Report Share Posted October 25, 2015 (edited) Calibration maybe. Filled no. There's a black plug on gauge where it was prolly filled. The screw comes out if turned hard enough. I left it flush like it is in picture. It works great now. I set it to 44 Edited October 25, 2015 by Preludedude Link to comment Share on other sites More sharing options...
scott87star Posted November 14, 2015 Report Share Posted November 14, 2015 Really, no one read this? I'd say a flow restrictor, just in case.... It's a safety device to keep your butt from getting showered in fuel if something really bad happens to the internal pressure sensing tube. Link to comment Share on other sites More sharing options...
Preludedude Posted November 15, 2015 Author Report Share Posted November 15, 2015 I read it. But sounded like opinion rather than fact. Thanks for helping me. I left it in and gauge is working perfect. Link to comment Share on other sites More sharing options...
psu_Crash Posted November 24, 2022 Report Share Posted November 24, 2022 On 11/14/2015 at 5:31 PM, scott87star said: Really, no one read this? It's a safety device to keep your butt from getting showered in fuel if something really bad happens to the internal pressure sensing tube. Smart! I had a fuel pressure sending unit die on me a few years back and it was spraying the engine bay. I was at an autocross and heard it ping when boost came on. Looked at a log and was WAY lean. Sure I smelled gas in the paddock, but with all the cars around I wasn't thinking it was me. Close call for sure Link to comment Share on other sites More sharing options...
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