sorry if this was posted in the wrong section. seemed like the most related.

I installed a FUll Blown double pumper kit about a few weeks ago.. and am having this weird issue, wanted to see if anyone else has any insight as to what I may have installed wrong or overlooked??

when I gear to about 1/4 of gas the car starts to randomly studder.. basically its running out of gas like if i was on empty BUT im not, i went to the gas station, filled it up and takes 11galons when before it would fill up to 14gallons or so. where are my extra 3 gallons going?? as soon as i fill her up everything is back to normal. I have no fuel issues anywhere else.

im sure i did the install just as it was supposed to be installed and the gas meter does work normally..

any help would be appreciated! thnx

 

You reversed the suction fitting upon install. You have to take it back out and switch it around. Make sure you do Teds fix for the fuel pressure issue.

 

how can the suction fittings be reversed? you mean the suction socks? being their the lowest point does it even matter if they are facing foward or back?

and also teds fix is if your running real rich at idle? I have no other issues, everything runs perfectly fine, my trims are small.. my only issue is just the 1/4 tank situation..

anyone else have some light to shed on this situation..

 

There is a "T" fitting on the bottom side of your pumper. This is what is backwards. It combines the return from the rail to "suck" the fuel from the other side of the tank. Ted's fix is for high fuel pressure at idle. Once you fix the suction "T" you will see the fuel pressure go through the roof.

I had the same problem you are having and I had the pumper in and out seven times.

 

i figured the T would not matter how it goes on since its kinda a Y ..there was no like directional flapper on it so i assumed it wouldnt matter how it went on..

so your saying once i fix the T my fuel pressure will be higher than what it is now? is that good or bad? i thought drilling out the T was to lower your fuel pressure?

 

thanks to cssaddictm4 i understand what my problem is. I will take the tank out tomorrow and fix the problem, ill take some pics and post them up in case anyone in the future runs into this same issue.

 

I've heard this can be an issue. Pictures would be greatly appreciated

Did it fix the problem you were having with the 1/4 tank of gas?


-Bink

 

He's running like champ. It's very easy to reverse the "Y" suction fitting. The orientation is an important part of Bernoulli's principle and its' function.

 

Thanks for the reply.

With this fix - would you recommend the full blown or the Buschur double pumper?


-Bink

 

i was told the buschur double pumper does not have that issue. i was told by my mechanic. that the full blown double pumpers has issues when u get to the 1/4 mark. When i was thinking about buying a full blown double pumper.

 

Both are great units, and both work FLAWLESSLY when installed CORRECTLY. Either one and you won't go wrong.

 

I hate to say this but cssaddictm4 isn't entirely correct.

The issue that you're referring to is when the passenger side of the saddle tank isn't having the fuel suctioned to the driver's side hence the siphon installed incorrectly. Your gauge reads 1/4 of a tank (there is 1/4 of a tank left in the passenger side saddle) but it isn't siphoning over so you can run out of gas at 1/4 of a tank.

I think the issue chamelieon is discussing is the same exact issue I had. When the tank was at 1/4 tank or lower if I took a left hander sharply the car went way lean. I could not do any 3rd gear logs at lower than 1/4 of a tank because it would go way lean and sputter. If I drove normally I could run the tank dry, I just couldn't drive hard. Since I could run the tank dry I knew the siphon was fine.

I wrestled with this for a month, checking saddle tank levels, messing with the floats, fixing the siphon, even going as far as to buying another siphon to make sure mine was good. In the end I sold the Full Blown and went Buschur...never have had the issue again. Keep in mind I had the stock line kit with mine, never went AN lines. I discussed it with Full Blown and they said it's only been reported a time or two and no resolution for the issue, they don't know why. The conclusion I drew is that with the Full Blown siphon hose being larger it could not create a strong enough suction due to the smaller stock return line to keep the pumps fed from that side of the tank so I had to ditch it. Hope this helps clarify and maybe chamelieon can chime in with which is his issue. Driving hard at 1/4 of a tank or the car running out of gas at 1/4 of a tank. Easiest way to check this is to try to run your tank dry. Can you drive easy and get to the E? If so your issue is the same that I mentioned, if not cssaddictm4 has the answer

On a side note the guys at Full Blown are A W E S O M E! I spent a few hours on the phone with them discussing the fuel system and learned a whole whole lot regarding the saddle tank, how it works, how the floats work, how the siphoning works, so on so forth. I'd recommend them to anyone but it just didn't work on my car.

 

full blown in my car working perfect. i made sure the siphon was installed just like the factory pump. i also measured the distance from the hat to the bottom of the pumps to make sure the pumps were all the way at the bottom of the tank. didnt use factory line kit. 6an feed/ stock return.

 

I concur with you...same story but with their Evo X hanger. I'm local so I had them pull it out and check the install for me...and it still never worked right. I ended up having them install a surge tank for me.

 

I have same issue and you are on point! I run -8 feed and -6 ret and my siphon is on correctly, I just don't go under 1/4! But just cruising I can run it real low! but I beat my car daily