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I think I might finish my car this weekend, shy of the fuel pump, and was wondering what the stock fuel pump will handle.

300whp? less?

Curious thats all, I dont plan on being nasty to it regardless... but if someone says the motor will blow AT 1psi then I may rethink this.

-Brad
 

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Ya Im about to run with the stock fuel pump, but Im only supercharging at about 280rwhp. Ive been told I should be fine but Im thinking about just spendin the extra cash and goin for an aftermarket one.
 

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I dont know the exact hp number, but I wouldnt even want to chance it. Just pay the $120 and get a walbro 255 with install kit.
Why don't you IS guys use the OEM Denso TT Supra pump. It has proven to be much more reliable. I have seen too many Walbro pumps fail. Just my $.02
 

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I was running lean with a S/C at 300hp and above 4k rpm
Ya, me too. At 3-4psi it could only get high 13's with the stock pump. With my imanage and an inline pump, I can make it 10.0 at 7psi with no issues.

Get a good wideband and keep an eye on it.
 

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Why don't you IS guys use the OEM Denso TT Supra pump. It has proven to be much more reliable. I have seen too many Walbro pumps fail. Just my $.02
Because the Denso pump is about $300! vs $100 for the Walbro. Any pump can fail, but Walbro's don't fail in hi enough numbers to say that it's a bad choice of fuel pump.
 

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the stock fuel pump is typically maxed out once you start boosting over 5psi.

in my opinion, there are already enough things that can go wrong when your boosting a car that is NA from the factory. just take the $150 hit and thats one less thing that can go wrong down the line, especially if you ever decide on upgrading
 

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Hey guys, do not run the Denso Supra TT pump... It draws twice the amperage as the Walbro pump, and the IS300's factory wiring cannot withstand the current draw (Denso = [email protected] vs Walbro = [email protected]). Unless you rewire the fuel pump circuit with a new relay/harness that can withstand continuous draw of 20A, best is to stick with a Walbro.
 

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^^interesting

i wonderif that's why my fuel pressure oscillates rapidly as of late....
 

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^^^not sure why it would oscillate, other than the obvious of there being different fuel demands depending on your driving... a fuel pump is either on or off, it doesn't operate at variable rates or voltages.
 

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a fuel pump is either on or off, it doesn't operate at variable rates or voltages.
I can't say about the stock in the tank pump but that's exactyl how my iManage works. It puts out more voltage to the booster pump depending on boost level. I can make it run between 1% - 100% duty cycle to increase fuel pressure.
 

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Hey guys, do not run the Denso Supra TT pump... It draws twice the amperage as the Walbro pump, and the IS300's factory wiring cannot withstand the current draw (Denso = [email protected] vs Walbro = [email protected]). Unless you rewire the fuel pump circuit with a new relay/harness that can withstand continuous draw of 20A, best is to stick with a Walbro.
I'm new to fuel, but is there anyway to run some kind of backup pump, I've seen a wahlbro fail and we all know, no gas = lean = boom.
 

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I'm new to fuel, but is there anyway to run some kind of backup pump, I've seen a wahlbro fail and we all know, no gas = lean = boom.
I'm telling you guys, get the TT Supra pump, get a 30amp relay and have the stock IS trigger the relay to turn on and you will have 0 problems. The stock TT pump is an OEM Denso pump that Toyota has used with great success. It flows a ton of fuel and is super reliable. You can get them for around $200ish if you look hard enough. They will support 550whp. Then when you want to make some serious power you wire up dual denso pumps ;) But that is a different topic.
 

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I'm new to fuel, but is there anyway to run some kind of backup pump, I've seen a wahlbro fail and we all know, no gas = lean = boom
Ya I agree, but if the pump fails the car won't get a chance to be lean, it won't even run.

I think either way (walbro or TT setup) will work just fine as long as you pay attention to your wireing.
 

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I'm telling you guys, get the TT Supra pump, get a 30amp relay and have the stock IS trigger the relay to turn on and you will have 0 problems. The stock TT pump is an OEM Denso pump that Toyota has used with great success. It flows a ton of fuel and is super reliable. You can get them for around $200ish if you look hard enough. They will support 550whp. Then when you want to make some serious power you wire up dual denso pumps ;) But that is a different topic.

I believe one of the issues is size. The denso unit is bulky. It would nearly be a complete PITA to try getting two denso pump on the hanging assembly.

You can easily setup with dual walbro 222lph for less than the cost of one denso pump. Cost effective is the name of the game.

Walbro works and I have yet to hear of any IS Boosted guys running into walbro pump failure.
 

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Ya I agree, but if the pump fails the car won't get a chance to be lean, it won't even run.

I think either way (walbro or TT setup) will work just fine as long as you pay attention to your wireing.
Well not 100% true. Fuel Pump can either suddenly die out or slowly die out. Which means if you're boosting and your engine is demanding more fuel for the amount of air that just suddenly got rushed in and your pump just can't supply the amount of fuel needed, you will lean out big time and toast your block. At that time, you will probably shit your pants also.
 

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Well not 100% true. Fuel Pump can either suddenly die out or slowly die out. Which means if you're boosting and your engine is demanding more fuel for the amount of air that just suddenly got rushed in and your pump just can't supply the amount of fuel needed, you will lean out big time and toast your block. At that time, you will probably shit your pants also.
The one thing that you guys are forgeting is that boost cut or fuel cut is exactly that, cutting the fuel off which kills the motor (shuts it down). You would only truly have an issue if it happened on a WOT pull. I run a fuel pressure gauge in the car so I can see what's going on with the fuel system to a degree. I've got dual pumps so I'd have to be pushing a lot of HP to know that one of the pumps is failing.
 

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I can't say about the stock in the tank pump but that's exactyl how my iManage works. It puts out more voltage to the booster pump depending on boost level. I can make it run between 1% - 100% duty cycle to increase fuel pressure.

interesting, actually i think i remember that from back when i had an imanage. i completely forgot, well the stock pump may be of similar... sorry for the unverified info.
 
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