Help - Search - Members - Calendar
Full Version: Walbro Upgrade Not Needed On Fuel System...?
Lexus Owners Club > Lexus Models > Lexus Imports > Aristo
skeet94
Hello there,

I just came across this VERY interesting thread on my main lurking forum -

http://www.supraforums.com/forum/showthread.php?t=404955

In summary: If you run a 8awg cable (any thicker is no good) to a relay and use that to power the fuel pump, it will give you a bit more leeway on the stock Denso fuel pump as it will provide it with a MUCH higher voltage than the stock "thin" wiring is capable of providing, in essence increasing flow. Therefore, not needing to upgrade to a Walbro in tank pump.

Think this may help the people who are running their fuel system to the max by going BPU++ (Yoshi, Dave Prolex, etc). I remember Yoshi pointing out in a previous thread if he went to 19psi or even spiked to 19psi then his A/F Ratio went lean enough to grenade his engine.
ProLex-UK
QUOTE(skeet94 @ May 18 2007, 03:29 PM) [snapback]438853[/snapback]
Hello there,

I just came across this VERY interesting thread on my main lurking forum -

http://www.supraforums.com/forum/showthread.php?t=404955

In summary: If you run a 8awg cable (any thicker is no good) to a relay and use that to power the fuel pump, it will give you a bit more leeway on the stock Denso fuel pump as it will provide it with a MUCH higher voltage than the stock "thin" wiring is capable of providing, in essence increasing flow. Therefore, not needing to upgrade to a Walbro in tank pump.

Think this may help the people who are running their fuel system to the max by going BPU++ (Yoshi, Dave Prolex, etc). I remember Yoshi pointing out in a previous thread if he went to 19psi or even spiked to 19psi then his A/F Ratio went lean enough to grenade his engine.


interesting..............I've gone walbro already biggrin.gif

Got some PE 245 litre per hour pumps due in which should be handy............excellent price as well...
jackal
What sort of price do the Walbro's come in at now then, are they 255L per hour correct me if im wrong biggrin.gif
Ahhhh__Aristo
Why risk pushing and ageing OEM pump beyond its normal working limits when you can get a Walbro for £60 to your door these days???

I got bored after page 1, is there a page where it gets better??
jackal
QUOTE(Ahhhh__Aristo @ May 19 2007, 10:35 AM) [snapback]439056[/snapback]
Why risk pushing and ageing OEM pump beyond its normal working limits when you can get a Walbro for £60 to your door these days???


£60 ohmy.gif that sounds cheap where's that from?
Ahhhh__Aristo
From the US
skeet94
Ahhhh__Aristo: Let's get at it again tongue.gif

The Denso has been proven more reliable than the Walbro...if you read through the whole thread instead of stopping after the first thread you'll notice that tongue.gif.

Also the pump is not being pushed beyond it's working limits - it's receiving it's recommended voltage instead of being undervolted as per the stock wiring...if it was being pushed as high as 15-16 volts then that would be pushing the pump beyond it's limits, which I wuold NEVER recommend. If you read through the thread, alot of people on there would run lean past 17psi on their small singles (61mm, 67mm turbo's), yet after performing the mod, they were running pig rich at 17psi and could run as high as 19psi using the stock fuel system with no lean spots whatsoever smile.gif

The Stock Denso has also been proven to 600rwhp too wink.gif.
Ahhhh__Aristo
My bad, I've now read to page 2, but I get bored easily, which reminds me................. sleeping.gif tongue.gif


I have no qualms about the Denso being more reliable than the Walbro and even flowing more at higher voltages. (although I've seen no test data, it's easily believable)

My main problem with it as stated before, these are old pumps. Lets look at yours, alot newer than my OEM, but yet still 8 years old (and covered x amount of miles/running time). You obviously spend a few quid on your car, would you seriously be happy to now do this mod??


I don't know how much the OEM pump is from Toyota, but going from US prices, looks as though it'll be around £200ish

The Walbro flows more at stock voltage. My Walbro cost me around £52 from the states to my door. Took me less than an hour to install, aswell as doing a "how to guide" in the process.

If I have to change this every few years as part of routine servicing for piece of mind, I have no problems with that.

I'm all for something different away from the norm, but I think when it comes to something like this, I'll stick with being a Lemming and follow the others.
skeet94
Ahhhh_Aristo: I do see where you're coming from...although if you're going to replace the fuel pump and have it run for another 100k miles PLUS - then you're just better off going the Denso route rather than the Walbro...the reason the Walbro flows more as a simple drop in is due to the low current draw compared to the Denso - but then I'd rather have a pump that's been proven on cars going up to 200k miles and giving it the recommended voltage wink.gif. I'd rather spend the £150 more on a Denso and having that peace of mind that my fuel pump will NOT fail so easily as it's something that is being used on Supra's/Aristo's approacing 200k miles with no signs of failure.

EDIT: If you've got approximately 60-80k miles on the car, then I see no reason why you should not have the stock denso rewired...it's easier, helps you prepare for the future when you go the route of a multiple pump setup or a single large external pump setup too.
Ahhhh__Aristo
I hear you smile.gif and fully appreciate all that.

I obviously can't agree with you fully, as that would be no fun msn-wink.gif biggrin.gif
skeet94
HAHA I understand completely tongue.gif
vazoosh
QUOTE(skeet94 @ May 22 2007, 03:50 PM) [snapback]439835[/snapback]
HAHA I understand completely tongue.gif

My aristo has 90,000 miles on the clock,will the stock denso still be ok if i upgrade the wiring to 8 guage or should i replace it,i'm on a tight budget!lol
skeet94
I'd upgrade the wiring regardless...I'd probably replace the pump at 90k just to be on the safe side - I've got 110k at the moment and a stock replacement Denso is DEFINITELY on my shopping list...should be picking one up in about a months time biggrin.gif .
vazoosh
I think i'll add the stock Denso to my shopping list too,might as well get everything done one time.Do i have to order this through Toyota or Elsewhere?
skeet94
You can pick it up through Toyota - or you could source one from the USA which would come to abput £90 odd - I'm still trying to find a good cheap source for mine wink.gif.
ProLex-UK
Got a P Enterprise 245 l/ph one tucked away. Tis a dinkylittle thing
vazoosh
QUOTE(skeet94 @ Jun 1 2007, 12:43 PM) [snapback]442339[/snapback]
You can pick it up through Toyota - or you could source one from the USA which would come to abput £90 odd - I'm still trying to find a good cheap source for mine wink.gif.

I think i'll give Toyota a visit tomato.gif thanx biggrin.gif
skeet94
The Denso will be quite expensive from Toyota smile.gif...if anything I would also look at the Power Enterprise unit that Dave has too as it has been proven to support enough power when going BPU... I'm just staying away from these units as the stock Denso has been proven to flow up to 600bhp with the correct recommended voltage supplied not to mention it works perfectly fine for well over a hundred thousand miles as has been proven by lots of high mileage Supra's/Aristo's.
yoshi
I have found I can run 1.2bar on pump fuel with the standard fuel pump, the Air/Fuel looks a-OK and sits about 11.9.

I guess with race fuel I could run 1.3bar and acheive 500hp. That is on stock turbo, engine, injectors and fuel pump.

If you're wanting to run past 1.2bar on pump fuel, you'll need a Walbro. You'll also need a bigger turbo + a bigger intercooler to go with it.
skeet94
QUOTE(yoshi @ Jun 18 2007, 08:32 AM) [snapback]446387[/snapback]
I have found I can run 1.2bar on pump fuel with the standard fuel pump, the Air/Fuel looks a-OK and sits about 11.9.

I guess with race fuel I could run 1.3bar and acheive 500hp. That is on stock turbo, engine, injectors and fuel pump.

If you're wanting to run past 1.2bar on pump fuel, you'll need a Walbro. You'll also need a bigger turbo + a bigger intercooler to go with it.


Hi Yoshi,

If you read through the thread, they're running anywhere upto 19/20psi on their US Spec turbo's which are known to make about 450rwhp (more power than our JDM's can give us)...they're also NOT maxing out their fuel system with this mod (albeit they use 550cc injectors to our 440cc injectors). The Denso has been proven upto 600rwhp, with the proper voltage given (14.4volts as opposed to 12.x volts it gets with the stock wiring).

You will also notice after performing this modification, they're ALL running pig rich ... so why spend more money on a Walbro, when the Denso has been proven to handle more power, and MUCH MORE reliably too?
This is a "lo-fi" version of our main content. To view the full version with more information, formatting and images, please click here.
Invision Power Board © 2001-2008 Invision Power Services, Inc.