View Full Version : Fuel Pump Placement
Tex2131
03-15-2018, 11:01 PM
I bought the Holly Sniper EFI and it came with an inline fuel pump. According to the installation instructions the pump should be mounted below the gas tank so gravity can keep it primed. That's easier said than done on the Mk4. I had planned to mount it on the 2"x3" frame above the fuel tank with the pre and post filters.
I'm thinking an in-tank pump is the way to go. Have any of you guys mounted an EFI inline pump up on that frame rail? Any problems?
Thanks, Don
Gordon Levy
03-15-2018, 11:22 PM
In tank pump is absolutely the way to go and very easy to do.
Itchief
03-15-2018, 11:33 PM
I agree with Gordon mine is in the tank
Rick
Mark Eaton
03-16-2018, 12:50 AM
Don, I have the Holley Sniper as well. I think most guys on the forum prefer the in tank pump. I'm going to go with this inline pump that my Sniper came with. It will be easy to change later if I don't like it. I made this bracket for it and installed it sort of like the guy does on the Holley website video. I'll take a photo with the tank this weekend and send it if you like.
https://thefactoryfiveforum.com/attachment.php?attachmentid=79589&d=1516590355
https://thefactoryfiveforum.com/attachment.php?attachmentid=79590&d=1516590371
I went with a Breeze in-tank pump. Went right in.
Tex2131
03-16-2018, 09:24 AM
Don, I have the Holley Sniper as well. I think most guys on the forum prefer the in tank pump. I'm going to go with this inline pump that my Sniper came with. It will be easy to change later if I don't like it. I made this bracket for it and installed it sort of like the guy does on the Holley website video. I'll take a photo with the tank this weekend and send it if you like.
https://thefactoryfiveforum.com/attachment.php?attachmentid=79589&d=1516590355
https://thefactoryfiveforum.com/attachment.php?attachmentid=79590&d=1516590371
That would be great Mark. Thanks!
rich grsc
03-16-2018, 09:25 AM
I would never put a filter on the suction side of a pump. It's ok to run a screen, like what is installed on an in-tank pump.
skidd
03-16-2018, 10:02 AM
I went Carb with an in-tank low-pressure pump....
But.. if I was to buy a Holley EFI Sniper setup, I'd sell the provided inline pump on Craigslist or ebay, and buy a good quality in-tank pump with the money.
Quieter, cleaner install, inexpensive replacements readily available at any parts store if it fails.
Just my 02c.
OVCobra
03-16-2018, 12:02 PM
There is no doubt that the intank pump is the ideal way to go (fuel cools the pump and you are not dealing with any potential of vapour lock) but an external pump can work. I went old school (carburetor) but have run an external electric pump for a very long time without issue (gerotor type pump). Pre & post filters absolutely recommended but filtration level important; pre-filter should be 100 micron ("coarse") to prevent debris from affecting pump internals while post filter can be 10 or 20 micron ("fine"). If you run fine filtration before the pump you increase the potential of fuel suction issues while after the pump you have ample pressure to get through a finer filter.
Be careful using a low pressure, carburetor filter as a pre-filter (as Tex 2131 appears to have done) as there is tremendous variation in filtration level and the more expensive/good ones tend to have finer filtration; great if filtering pressurized fuel but as noted could present excessive restriction on the suction side.
There are numerous manufacturers that make filters that you can select the filtration level, definitely work consideration.
Dave
Mark Eaton
03-18-2018, 07:28 PM
Ok Don, here is what it looks like with the tank in place.
https://thefactoryfiveforum.com/attachment.php?attachmentid=82795&d=1521418975
https://thefactoryfiveforum.com/attachment.php?attachmentid=82796&d=1521418997
and from the other side
https://thefactoryfiveforum.com/attachment.php?attachmentid=82797&d=1521419015
I think its low enough. I trust Holley they've been around a while. I don't think they would sell something that didn't work. Also, Mike Forte made the call of this one. He built my engine, I just told him I want EFI and this is what he sent.:)
In tank pump is absolutely the way to go and very easy to do.
I used Gordon's fuel pump "kit" - works perfectly.