halllon Posted February 15, 2010 Share Posted February 15, 2010 Hey guys, I have a few questions related to the stock MKIV fuel system. The car in question has two Walbro intank pumps installed and the fuel damper removed and replaced with a regular banjo. The car is mapped on E85 and we are now upgrading to a single maxing out at about 550whp. 1. How much power does our current fuel system support (on E85)? 2. What are the exact limitations in the stock fuel system? Is it the fuel filter, the banjos on the filter and the ones leading up to the fuel rail, the inner diameter of the pump hanger or the inner diameter of the fuel lines? We need your recommendation for the exact modifications needed to support 550whp on E85. We don't want to invest in an entirely new, complete AN fuel system if we don't have to. Thanks in advance! Quote Link to comment Share on other sites More sharing options...
nigelboyne Posted February 15, 2010 Share Posted February 15, 2010 is it a european supra or jap spec. either way i think you need a fuel system that would support 700hp+ or so on road fuel plus very large injectors. Quote Link to comment Share on other sites More sharing options...
Wez Posted February 15, 2010 Share Posted February 15, 2010 Much bigger injectors, you need about 3rd more fuel to get the same power on E85 which is why I have gone from 650cc to 1000cc Quote Link to comment Share on other sites More sharing options...
halllon Posted February 15, 2010 Author Share Posted February 15, 2010 Thanks guys, I forgot to mention we will run 1000cc injectors and a HKS style fuel rail. I only need to know the fuel system modifications needed between the pumps and the fuel rail. The car is a JDM VVTi btw. Quote Link to comment Share on other sites More sharing options...
nigelboyne Posted February 15, 2010 Share Posted February 15, 2010 2 uk denso/ or walbro fuel pumps Quote Link to comment Share on other sites More sharing options...
bondango Posted February 15, 2010 Share Posted February 15, 2010 Although 550hp can be supported on stock fuel system using basic components and drop in 650cc injectors, as said you will need at least 850cc injectors to support the same power with E85. At this point you are pushing the stock componets i.e. lines and rail to there limts of flow. A top feed rail and top feed injectors can often cost less than Dropins for the stock rail, which would mean you could get away with a single 6an run of line from the tank>>AN Filter>>Rail and then return to a AN equiped regulator and use the stock return line. Not really worth skimping on the Fuel system TBH Quote Link to comment Share on other sites More sharing options...
T2 MSW Posted February 15, 2010 Share Posted February 15, 2010 Although 550hp can be supported on stock fuel system using basic components and drop in 650cc injectors, as said you will need at least 850cc injectors to support the same power with E85. At this point you are pushing the stock componets i.e. lines and rail to there limts of flow. A top feed rail and top feed injectors can often cost less than Dropins for the stock rail, which would mean you could get away with a single 6an run of line from the tank>>AN Filter>>Rail and then return to a AN equiped regulator and use the stock return line. Not really worth skimping on the Fuel system TBH Hang on we are talking whp here not fwhp are we not? In which case your going to need larger injectors that 850's. Im running about 511 whp on 850 injectors with pump fuel and thats running 71% duty. So on E85 your going to be on the limit. Quote Link to comment Share on other sites More sharing options...
halllon Posted February 15, 2010 Author Share Posted February 15, 2010 ... which would mean you could get away with a single 6an run of line from the tank>>AN Filter>>Rail and then return to a AN equiped regulator and use the stock return line. Not really worth skimping on the Fuel system TBH Thanks What's the best way to run AN6 from the pumps? Drill a new hole and run an AN6 "bulkhead" fitting through the pump hanger? Quote Link to comment Share on other sites More sharing options...
bondango Posted February 16, 2010 Share Posted February 16, 2010 Hang on we are talking whp here not fwhp are we not? In which case your going to need larger injectors that 850's. Im running about 511 whp on 850 injectors with pump fuel and thats running 71% duty. So on E85 your going to be on the limit. yes...Im talking generally, im not giving him an exact upgrade path im merely pointing out the weakness and restrictions in using the stock components Quote Link to comment Share on other sites More sharing options...
halllon Posted February 16, 2010 Author Share Posted February 16, 2010 Thanks guys, We have the injector sizes and the fuel rail/FPR upgrades sorted, we just need to know the flow limitations of the fuel lines themselves. I think we will go with bondango's advice and run the following: 2 x in-tank Walbros -> 2 x AN6 bulkhead fittings through pump hanger -> 2 x AN6 to 1 x AN8 Y-block -> AN8 hose all the way (through a properly sized 10 micron filter) -> Fuel rail / 1000cc's -> stock return line. Will this setup flow sufficient amounts of E85 fuel for 550whp? Quote Link to comment Share on other sites More sharing options...
bondango Posted February 16, 2010 Share Posted February 16, 2010 Thanks guys, We have the injector sizes and the fuel rail/FPR upgrades sorted, we just need to know the flow limitations of the fuel lines themselves. I think we will go with bondango's advice and run the following: 2 x in-tank Walbros -> 2 x AN6 bulkhead fittings through pump hanger -> 2 x AN6 to 1 x AN8 Y-block -> AN8 hose all the way (through a properly sized 10 micron filter) -> Fuel rail / 1000cc's -> stock return line. Will this setup flow sufficient amounts of E85 fuel for 550whp? Thats the method i would use, or you could run 2 6AN lines from the pumps. i have seen some people retain the stock line for 1 pump with a AN fitting on the stock filter, and running a seperate AN6 line from other pump to rail (via inline filter), but wouldnt recommend this myself. Quote Link to comment Share on other sites More sharing options...
bondango Posted February 16, 2010 Share Posted February 16, 2010 Hang on we are talking whp here not fwhp are we not? In which case your going to need larger injectors that 850's. Im running about 511 whp on 850 injectors with pump fuel and thats running 71% duty. So on E85 your going to be on the limit. You would be close to the limit on 850cc injectors, its just down to too how close to the edge your willing to go, and how good your mapper is Example Engine: Stock, 272 cams Gearbox: BL automatic Fuel: Pump E85 Mods: T4 74mm, 900cc injectors, twin TT pumps, AEM EMS 620WHP http://www.inductionperformance.com/customerdyno/toyota/vince-e85.jpg Quote Link to comment Share on other sites More sharing options...
halllon Posted February 16, 2010 Author Share Posted February 16, 2010 (edited) Yeah, I guess the max power you can make on given injectors is pretty much down to the fuel pressure you run (within reason). We ran 396 whp on a completely stock VVTi 2JZ with stock USDM 2JZ-GTE injectors and E85. That run saw 96% duty cycle, and we still ran 4.5 bar fuel pressure on a 1:1.5 rising rate regulator... Edited February 16, 2010 by halllon (see edit history) Quote Link to comment Share on other sites More sharing options...
bondango Posted February 16, 2010 Share Posted February 16, 2010 Yeah, I guess the max power you can make on given injectors is pretty much down to the fuel pressure you run (within reason). We ran 396 whp on a completely stock VVTi 2JZ with stock USDM 2JZ-GTE injectors and E85. That run saw 96% duty cycle, and we still ran 4.5 bar fuel pressure on a 1:1.5 rising rate regulator... i seen the car at PD Round 3 starup and couldnt believe how it performed on stock turbo's Very well setup car Quote Link to comment Share on other sites More sharing options...
halllon Posted February 18, 2010 Author Share Posted February 18, 2010 i seen the car at PD Round 3 starup and couldnt believe how it performed on stock turbo's Very well setup car Cheers Marty! The car wasn't remapped back then, it ran bone stock management and regular fuel. Only mods were air filter, FMIC and the exhaust removed. Boost peaked at 1.4, and I had to lift off and reapply throttle every three or five seconds to avoid boost cut coming into effect... Lol Here's a short video from Prodrift Series Round 3 2008 at Sturup: Quote Link to comment Share on other sites More sharing options...
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