Technical Options for a new LPFP? Stock one is getting weak....

martymil

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It really depends on the type of driving you do and how low you run your tank.

A bucket less setup flows around 20 to 30% more fuel than a bucket system.

The bucket system is very restrictive in terms of flow.

I'm still testing my bucketless custom system and have no starvation issues even when the needle is below zero.
 

houtan

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It really depends on the type of driving you do and how low you run your tank.

A bucket less setup flows around 20 to 30% more fuel than a bucket system.

The bucket system is very restrictive in terms of flow.

I'm still testing my bucketless custom system and have no starvation issues even when the needle is below zero.

are you planning to share details once testing is done? Is it the hydromat that gets rid of the below 1/2 tank issues?
 

martymil

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I already shared it and still long term testing, I never release products prematurely.

 
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houtan

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I already shared it and still long term testing, I never release products prematurely.


nice. Are you planning on selling the bracket and fittingn on the pump a la carte? Any idea on ballpark price?
 

martymil

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Plan is to get in under a 100 dollars shipped for the fitting, the rest can be had from any bucket less pump provider.
 
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IQraceworks

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I’m hoping that with the BMP 90 degree walbro fitting, and no other rubber lines or clamps to fail…this setup should be pretty reliable. Yes, I’m going to cut the bottom out of the bucket, but I’m not planning on ever tracking my car….except for a few passes down the drag strip. Tons of people run bucketless setups……and it sounds like as long as you don’t let your fuel tank get low when you are at the track, you don’t really have many issues.

I would think that as far as reliability goes, it should be close to the oem unit……as long as that new 450 pump doesn’t pull so many amps that it cooks the EKP…..but I don’t really hear of too many people having issues with that. I guess time will tell.
 
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houtan

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Yeah I agree, the bmp fitting seems like an extremely reliable set up. Back to square one for me, I failed to realize it doesn’t have a connection for the Venturi.
 

IQraceworks

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How big of a deal is it to not run the Venturi, and just cut the bottom out of the bucket? That was my original plan.

Also.....I went with the F90000267 Walbro 450 that runs at 87psi....but I see that Precision Raceworks and some other companies are running the 112psi version of the same pump (F90000274).

Any reason why the lower pressure 267 pump won't work? I'm assuming it should pull less amps, and be easier on the EPK?
 

houtan

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The modification to the bottom of the bucket isn’t a big deal even with my basic skill set. I just dont want to run a bucketless set up that requires me to be at half tank. I burn through a tank of gas when I go for drives through the canyons here and am at a 1/4 tank before I get to a gas station. Martymil’s set up look promising, but will have to wait until final testing is done. Or I can go the hose clamp/t-fitting route. I’m not in a rush at the moment so that’s good.
 

IQraceworks

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I've heard that the bucketless setups really aren't an issue unless you are taking long sweeping high G turns on a track....or is that BS? Are you saying that normal "spirited" driving is an issue with that type of setup?
 

martymil

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Bucketless setup tend to starve when cornering hard and it doesn’t have to be high g's for them to do so.

In straight line they have no issues.

Thats why i took it upon myself to make this hydramat setup but due to covid and tracks being closed it's delayed testing.

Hopefully I'll have some decent data by the end of the month
 

Torgus

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I don't see the desire to run bucketless. The cons seem to outweigh the pros...

Just add another 450 pump and FPR and you will have more fuel that you will ever likely need(875whp on 100% E85). Look at the cost of hydramats $200 each.

Edit: There is a reason basically every vehicle manufacturer for the last 30+ years has used a bucketed design.

From PR:

Stage 3 (4.3 gallons per minute)
Our Stage 3 bucketed fuel pump includes all necessary wiring and pump activation switch (hobbs switch). This pump boasts dual Walbro 450 (F90000274) fuel pumps and can support up to 1000whp* (Rated for 875whp on 100% E85) and is ready to grow with you as your needs demand. With a modular plug and play design this kit can be upgraded with our Stage 3.5 or Stage 4 module and have everything you need to match your future horsepower goals.

While all bucketless fuel pumps flow .2gpm more than a bucket design that retains the venturi it comes at a cost. Bucketless pumps should not be driven on tanks lower than ¼ full and should not be used for road course racing. This is not a disadvantage of only bucketless designs but also a disadvantage for any bucket design which deletes the venturi. If you do not plan on road course racing (not street racing) and are responsible at maintaining ¼ tank of fuel during spirited driving bucketless pumps can be a cheaper alternative for you.
 
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IQraceworks

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I don't see the desire to run bucketless. The cons seem to outweigh the pros.

Just add another 450/535 pump and FPR and you will have more fuel that you will ever likely need. Look at the cost of hydarmats.

For a DIY setup....I didn't want to keep the bucket in tact and then plumb in a separate fuel line with fittings and extra clamps for that Venturi that sits at the bottom. That's a lot more stuff to fail, break, or come lose over time.

By cutting out the bottom of the bucket, I can now skip all of that extra plumbing for the Venturi.....and just run a single clamp on BMP fitting from the pump right to the OEM fuel line fitting. If I get more flow....great, but my biggest concern is all of that extra plumbing to keep the Venturi hooked up.

I've heard of people keeping the bucket in tack and NOT using the Venturi (relying on the return lines to fill the bucket).....but I would think that might lead to fuel starvation issues also.

Thoughts?
 

houtan

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For a DIY setup....I didn't want to keep the bucket in tact and then plumb in a separate fuel line with fittings and extra clamps for that Venturi that sits at the bottom. That's a lot more stuff to fail, break, or come lose over time.

By cutting out the bottom of the bucket, I can now skip all of that extra plumbing for the Venturi.....and just run a single clamp on BMP fitting from the pump right to the OEM fuel line fitting. If I get more flow....great, but my biggest concern is all of that extra plumbing to keep the Venturi hooked up.

I've heard of people keeping the bucket in tack and NOT using the Venturi (relying on the return lines to fill the bucket).....but I would think that might lead to fuel starvation issues also.

Thoughts?

per PR, you still run the risk of running the bucket dry without the Venturi.
 
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IQraceworks

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If that's the case....I think I would still rather cut the bottom out of the bucket and use the BMP fittings vs. plumbing an extra t-fitting, hose, and multiple extra clamps in order to plumb in the venturi.
 

houtan

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Ok back in business. I don’t know how I missed this in the Wordpress blog. All you need is this: https://www.amazon.com/Dorman-800-177-Fuel-T-Connector-Piece/dp/B00CMB4I62

This connects to the hose from the Venturi and to the bmp fitting. So two hose clamps need for the Venturi hose. That’s acceptable imo. I will use the same cinch on type hose clamps and a rivet gun like in the diy (two new tools I just bought for about $30).
 

IQraceworks

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Yep...that looks like a pretty easy way to still use the venturi. Are those plastic dorman fittings ethanol compatible? I get nervous when you start using plastic fittings if you don't know what they are rated for.

I'm still trying to get a feel for how bad an open bucket system really is........
 

IQraceworks

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I drag race, in fact I just went on Saturday. Started with 3/4 and left with 1/4 tank with no issues bucketless setup.

From what I've gathered......you only starve the bucketless setups if you are doing hard cornering.....not straight line acceleration. Must be the placement of the pump or something??