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Dual Fuel Filter Mod

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Old 04-10-06, 05:49 PM
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Dual Fuel Filter Mod

Hi guys. I've always figured that one of the biggest restrictions in the fuel system is the whimpy little fuel filters that we have been given. One that is even slightly dirty will have a noticeable effect on overall horsepower at wide open throttle.

No rocket science here, but I figured I'd put together a post anyway that included the part numbers and cost involved. Take a look, and let me know what you think.

Two T fittings = 5.50 each
5' of 5/16" fuel line = 5.00
2 fuel filters = 6.00

To support the entire assembly, I simply bent some coat hanger wire and covered it with some vacuum line to keep it from wearing on anything important. Then I bolted the wire to a spare stud where the original fuel pump cover mounted (in the process of installing a Carter pump now).
Attached Thumbnails Dual Fuel Filter Mod-cimg3236.jpg   Dual Fuel Filter Mod-cimg3237.jpg   Dual Fuel Filter Mod-cimg3239.jpg   Dual Fuel Filter Mod-cimg3240.jpg   Dual Fuel Filter Mod-cimg3241.jpg  

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Old 04-10-06, 06:13 PM
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looks cool enough, but what is the benifit? i use a glass filter with replacable inner screens. no more prob. I run a 465 holley. not turbo but works.
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Old 04-10-06, 06:26 PM
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Pretty sharp. More up time between filter changes.

I use the big fat FRAM one in the REPU, bigger than an oil filter and filters down to 10 microns compared to >150 for the ones above.
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Old 04-10-06, 06:31 PM
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LOL. A few months back I started a post looking for a better fuel filter option. Lots of responses, but no worthwhile information ever came out of it. Now that I go through this little bit of trouble, I start hearing about better alternatives. Figures...
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Old 04-10-06, 06:34 PM
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why put two looks good
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Old 04-10-06, 06:39 PM
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i applaud ingenuity, but why not a better flowing, better filtering replacement?
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Old 04-10-06, 06:42 PM
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Originally Posted by jjlrx7
looks cool enough, but what is the benifit? i use a glass filter with replacable inner screens. no more prob. I run a 465 holley. not turbo but works.
Same here! I use a stock filter in the rear and a glass filter right before the carb. Works fine.......but thats great idea!
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Old 04-10-06, 06:46 PM
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YA looks nice, i use a brass filter right infront of the carb. Its one of those Chrome Red ones for about 25 bucks. i havent changed the rear one, i guess i should. Its been prolly two years since its been done.
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Old 04-10-06, 06:58 PM
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Cool. 'Tis a good idea for those of us who can't find a better filter alternative. Heck, look at the last line of my signature!

Jon
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Old 04-10-06, 07:12 PM
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Thats a pretty interesting idea though, definately should help the flow.

And slow down the demise of the filters such as the dirty one in my avatar I pulled when I first got the car.
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Old 04-10-06, 07:30 PM
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I considered just getting a larger filter, but it still only has one intlet and one outlet, so who's to say that it will flow better? I'm sure it would filter better (presumably), but flow?

Anyway, using two stock filters will cut the load demand to 50% on each one. So each filter will keep up fine as long as it does at least a halfway decent job. I always felt that the stock filter was just barely able to meet the flow demands of the stock system (if that), so now it only has to work half as hard and I'll still get good flow.

Here's the thread where I first started fishing for ideas on this. https://www.rx7club.com/showthread.p...ht=fuel+filter
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Old 04-10-06, 07:37 PM
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i bought one knew fuel filter yesterday (the same one you have in the pics), but i cannot locate where the other one goes, only one of my lines seemed to have a filter on it
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Old 04-10-06, 07:42 PM
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Umm, this is a modification to allow the use of two filters for better flow...
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Old 04-10-06, 07:48 PM
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Originally Posted by Kentetsu
Umm, this is a modification to allow the use of two filters for better flow...
yea i got that, but is there a filter for the other line? cause i couldnt find one, seemed to be straight from the pump

i think im gunna run back to the store tonight and get these parts, and try this aswell
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Old 04-10-06, 07:51 PM
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I wonder how many Tee's Advance auto has in stock... Why stop at two filters?
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Old 04-10-06, 07:51 PM
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There is two under the hood on the carb, one on each fuel line, aswell as one under the back of the car, on the chassie.
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Old 04-10-06, 08:03 PM
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Originally Posted by chedda_j
There is two under the hood on the carb, one on each fuel line, aswell as one under the back of the car, on the chassie.
thx, i only see one close to the carb and that was the one i replaced, so ill go searching for the rear one under the chassie and go to buy the other one tonight
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Old 04-11-06, 12:46 AM
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what about getting a filter for 3/8" lines? it should squeeze into the 5/16" line and flow more. Thats probably what I'm going to be putting on my carb unless anyone knows better. plus my carter was listed as having 1/4" inlets and outlets but these are defenitely 3/8".

what do you guys think about this one on summit. Russel Aluminum

sorry for the hijack and great idea by the way. Gotta love some good ol' ingenuity.

edit: woohoo post #300!
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Old 04-11-06, 01:07 AM
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The exact one i have.
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Old 04-11-06, 01:40 AM
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http://store.summitracing.com/partde...5&autoview=sku

Considered it an investment in my carb and motor's future. At the end of a day of autocrossing the motor would stutter and run rough. Installed this filter, no more. Crud in tank would come loose and plug carb jets. Even after I relined it myself. Stock lining was still in there and flaked off

Filters MUCH better than the G2 Fram filters. Dropped 0.25psi mesaured at the carb. No biggie, just upped the fuel pressure!
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Old 04-11-06, 03:40 AM
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Originally Posted by DriveFast7
http://store.summitracing.com/partde...5&autoview=sku

Considered it an investment in my carb and motor's future. At the end of a day of autocrossing the motor would stutter and run rough. Installed this filter, no more. Crud in tank would come loose and plug carb jets. Even after I relined it myself. Stock lining was still in there and flaked off

Filters MUCH better than the G2 Fram filters. Dropped 0.25psi mesaured at the carb. No biggie, just upped the fuel pressure!
DAMN! Now that's my kind of filter!
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Old 04-11-06, 04:04 AM
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Holly ****. Thats tight. You can totally see my filter in this picture, you think that my dirty filter (chassie one) could be robbing that much power? It looks black, and the car is kinda slow. Hasnt been changed for years. i did a coversion chart and it said that i should be running about 18 seconds in the quarter with my setup, im running prolly 22. Thats sad. Gotta work on that ****.

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Old 04-11-06, 03:56 PM
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Change your fuel filter today! You will definitely notice a difference. I have a very clean tank, but even after a couple of months using a filter I will notice a difference with a new one. Less than 4 bucks, and fifteen minutes to swap it out even if you're holding a beer in one hand...
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Old 04-11-06, 05:13 PM
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I took your advice and changed the filter, the last one i couldnt even blow through, holly ****, total increase in power. id say 20%, i went to go turn a corner at a normal rate and tapped the gas and it shot me sideways, as where before i would have to turn a corner overly fast and pound the gas.

Oh ya and the car idles, still lopes because i need to do the CP mod, but it runs 10x better.
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Old 04-11-06, 05:25 PM
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Good to hear man! I'm hoping that this dual filter setup will help to keep the power up for a longer period of time between filter changes. This way, even if the filters are flowing at half-rate I'll still have full flow to the carb. I guess we'll see....
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