Fuel Starvation Fix - Siphon Pump Kit?

**AlpineM345** · 08-15-2020, 04:38 PM

Hi all,

Around 1/2 tank mark, my E36 M3 track car exhibits a fuel starvation issue when taking a long right hand corner. I was set on purchasing a Bimmerworld dual pump kit to cure the issue, but I found something interesting/intriguing:

https://rallyroad.net/products/rally-road-siphon-pump
http://www.radiumauto.com/Venturi-Je...-Kit-P760.aspx

Does anyone have experience with either of these kits? In theory, they should work, and they are considerably cheaper than a dual pump kit I was going to purchase. I guess I could be a guinea pig and try it out...

**SamE30e** · 08-15-2020, 06:56 PM

I don't have experience on an E36, and I've never had fuel starvation issues on mine.

But this is how the factory late model BMW's work. So I don't see why it wouldn't on an E36. I actually thought about buying a siphon jet line from a late model car and fitting it.

I'd try this before adding a second pump.

**vpilarry** · 08-16-2020, 07:33 PM

E30s have a siphon system to pull fuel from 1 side of the tank to the other but it wasn't enough to keep up in my track car so I went to a 2nd pump set up.

**yellow914** · 08-17-2020, 09:24 AM

I just installed the Rally Road kit. I put a brand new VDO fuel pump in and installed the siphon on the drivers side. With a few brass adapters I was able to reuse the factory crossover line.

It works perfectly on the street, I’m able to run right down to the fuel light. I tried it on track at Road America last weekend and I still get fuel starvation in the carrousel at over 1/2 tank, so no real improvement over the stock siphon.

I’m pulling it out shortly to put in the 2nd fuel pump. For shipping, I’ll send it to you if you want to try it for yourself.

Sent from my iPhone using Tapatalk

**AJLM34A** · 08-17-2020, 02:25 PM

Originally Posted by yellow914

For shipping, I’ll send it to you if you want to try it for yourself.

Dibs if he does not want your setup.

**AlpineM345** · 08-17-2020, 11:57 PM

Originally Posted by yellow914

I just installed the Rally Road kit. I put a brand new VDO fuel pump in and installed the siphon on the drivers side. With a few brass adapters I was able to reuse the factory crossover line.

It works perfectly on the street, I’m able to run right down to the fuel light. I tried it on track at Road America last weekend and I still get fuel starvation in the carrousel at over 1/2 tank, so no real improvement over the stock siphon.

I’m pulling it out shortly to put in the 2nd fuel pump. For shipping, I’ll send it to you if you want to try it for yourself.

Sent from my iPhone using Tapatalk

Thanks for the offer. I think I am going to stick with the dual pump system instead of trying this out and having to re-do the whole thing again.

**pbonsalb** · 08-18-2020, 07:01 AM

What about a Holley hydramat? https://www.holley.com/products/fuel_systems/hydramat/

**NeilM** · 08-18-2020, 02:31 PM

I've had the Bimmerworld dual pump setup on my track car since 2003, and it'll go right down into the reserve light on track with no starvation. This is not to say that there's no other workable solution, but you know...

Neil
96 M3

**ScotcH** · 08-18-2020, 02:38 PM

Originally Posted by pbonsalb

What about a Holley hydramat? https://www.holley.com/products/fuel_systems/hydramat/

That works great ... inside our fuel cell

**AlpineM345** · 08-18-2020, 09:19 PM

Originally Posted by pbonsalb

What about a Holley hydramat? https://www.holley.com/products/fuel_systems/hydramat/

I have looked into a hydramat before. I think it ends up being pretty darn expensive unless you stick with a small size mat and hope that it will work well in a stock gas tank.

Originally Posted by NeilM

I've had the Bimmerworld dual pump setup on my track car since 2003, and it'll go right down into the reserve light on track with no starvation. This is not to say that there's no other workable solution, but you know...

Neil
96 M3

Yeah, I think I will stick with a dual pump setup. Fingers crossed it will work well in my car as I have seen some mixed reviews.

**pbonsalb** · 08-18-2020, 10:44 PM

I was thinking small size mat. How much fuel can a 3.2L use in 2 seconds?

**Kevin325i** · 08-21-2020, 06:43 PM

Rough math as usual 300cc/min injector at 100% DC gives you 60cc or .0158 gallons.

Carousel at Road America it's probably closer to 6-7 seconds. But not sure for an e36 and you're certainly not at full load for that.

Honestly if series allows putting in a surge tank is the way to go.

**pbonsalb** · 08-22-2020, 09:31 PM

Yes, forgot about surge tank. Whichever is cheaper between that and the smallest hydro mat should give you the 2 ounces of fuel you need in your pickup, or 12 ounces if at Road America.

**aeronaut** · 08-23-2020, 10:03 AM

I went round and round with all these options, comparing and thinking about them for over a year.
hydromat: couldn't find anyone what had tried one in an BMW OEM tank.
surge tank: plug and play solutions hard to find and/or expensive. Usually puts fuel system components in the cabin. Heaviest solution.
So I bought bimmerworlds dual pump conversion.
With a calibrated sensor, I'll get a fuel hick-up around 1gal in the tank. It just works.

**SalahHH83** · 08-24-2020, 02:49 PM

I've been running a dual pump set up for 7 years and it's been perfect. I've literally had my car at a 45 degree angle and it didn't fuel starve

**poweredbyg60** · 08-25-2020, 06:11 PM

another for the Bimmerworld setup!

**AlpineM345** · 08-27-2020, 12:00 AM

Thanks everyone. I am going to stick with the BW dual pump setup as it appears to be working well for most of people.

**JS154** · 09-03-2020, 03:53 PM

Dual pump plus surge tank from ireland Engineering.

I've heard mixed reviews on the hydramat effectiveness.

**ScotcH** · 09-03-2020, 05:26 PM

Originally Posted by JS154

Dual pump plus surge tank from ireland Engineering.

I've heard mixed reviews on the hydramat effectiveness.

Best setup for sure ... but you'd better know how much fuel you have! With our setup, if it starves in a corner (ie, low FP warning on dash), I have not enough fuel to get into the pits. Basically, 1/2 a lap left!

Hydramat works great ... in a fuel cell.

**golgo13** · 09-03-2020, 06:23 PM

My Bimmerworld two pump set-up is still going strong on 2.5 years.

**BlackHawkRacing** · 09-08-2020, 08:29 AM

Has anyone DIY the BW setup? I spent a whole 15 minutes looking into to before deciding the kit was less of a headache, but looking again, it seems like it would be pretty straight forward.

**ScotcH** · 09-08-2020, 09:28 AM

Originally Posted by BlackHawkRacing

Has anyone DIY the BW setup? I spent a whole 15 minutes looking into to before deciding the kit was less of a headache, but looking again, it seems like it would be pretty straight forward.

Yeah, the issue is the 13mm and 8mm adapters. You can find some 1/2" and 5/16" but when I looked it ended up being bunch of joints to get the right T and adapters made. Certainly possible, but the BW kit cost is mainly the pump anyway ... the hoses and fittings are pretty cheap part of the kit.

**fbirch** · 09-08-2020, 06:59 PM

Just ordered this kit last night as part of BW's Labor Day rebate sale. With a few extra G's on tap my car will now begin starving at slightly over 1/2 tank. Happened on the last lap of a race this past weekend.

Question for the group: My current fuel pump seems to be working fine. Any reason not to leave it in place and save one of the two new pumps as a backup? My car is a '99 and the pump is original as far as I know.

**aeronaut** · 09-09-2020, 08:31 AM

Or, replace both so you'll never have to touch them again, and save the old one for a few years until you've looked at it 37 times wondering what you'll ever use it for and finally toss it.
(Not that I've ever done that.)

**BlackHawkRacing** · 09-09-2020, 09:18 AM

Originally Posted by aeronaut

Or, replace both so you'll never have to touch them again, and save the old one for a few years until you've looked at it 37 times wondering what you'll ever use it for and finally toss it.
(Not that I've ever done that.)

I have every part I've taken off the car (that wasn't destroyed in the removal process) sitting on a shelf because I am convinced I am gonna need it again one day...