Dual Walbro fuel pumps

[makipsee]

is anyone running a dual walbro fuel pump in there mkII? if so how hard was it 2 install?

[williamb82]

not yet. will be though. hehehe.

http://supraforums.com/forum/showthread.php?t=225290&page=2&pp=25&highlight=dual+walbro

http://supraforums.com/forum/showthread.php?t=184580&highlight=dual+walbro

and some pics ive collected here

http://pg.photos.yahoo.com/ph/williamb82/album?.dir=b1e6&.src=ph&store=&prodid=&.done=http%3a//photos.yahoo.com/ph//my_photos


having a prob bringing up the thread with the dual feed rail info. ill post it later.

edit, here it is

http://supraforums.com/forum/showthread.php?t=310314&highlight=dual+feed

[drftsupramk2]

crazy shit!

[makipsee]

so the mkIII fuel tank and the mkII fuel tank r the same?

[CJSREDPRA]

so the mkIII fuel tank and the mkII fuel tank r the same?

No, where did you get that idea from?????

Shape between the 2 is different..... Because the capacities are different.....

MKII gas tank: 16.1 gallons.

MKIII gas tank: 18.5 gallons.

They don't interchange.

Also the 82/83 tanks have external fuel pump. 84+ has internal fuel pump. This can be changed to a external FP set however.

[makipsee]

i thought they were b/c william was posting things about dual walbros for mkIII's so i thought they might have been the same

[Funkycheeze]

the pump assembly that drops into the later model mk2 tanks is the same as the pump assembly for the mk3 tanks, so the mk3 walbro works in the later model mk2s

if you are using the high pressure walbro (external or internal) in your mk2, there is no reason to upgrade to dual pumps unless you are running injectors larger than 700CC

the GSS341 can flow 250+ LPH at over 60 PSI, so lets do some math

250/60 = 4.167 LPM (litres per minute)

4.167 * 1000 = 4167 cc/min

4167/6 = 694 cc/min

((720-694)/720) x 100 = 3.6 <-- this means you can run 720s at up to 96.4% duty cycle, which is more than you would ever want to

[makipsee]

well in time i plan on swaping in a 2jzgte then after that im looking for around 650 rwhp so ill need the duals ...which years are later models?

[williamb82]

i posted pics of mkiii's cause thats whats been done so far and its much much closer to the mkii setup then the mkiv. and even if running 720's, id recomend dual pups with a dual feed rail to counteract pressure fluctuations in the rail at high flow. sure you COULD run just 1 pump, but i wouldnt trust it.

[makipsee]

ooo ok i understand.....i know i wouldnt trust it either what a chance of a lean spot....thats y i plan on running duals with 720 injectors

[pdupler]

William et. al., I was considering a dual pump, but in series, one internal and one external but I'm not clear on the logic. Thing is that with the rising rate fuel pressure regulator that can hit over 80psi at full boost I went through several expensive aftermarket pumps that apparently couldn't handle the spikes. In talking with somebody once upon a time, it was suggested that dual pumps in series would handle pressure better while dual pumps in parallel would handle volume better. I researched the dual pump issue only a little and never went any further because of the extra amperage draw - essentially one pump draws about 7amps and a second I reasoned, would draw seven more from the mk2s feable and already overtaxed electrical system. Is dual in series a reasonable thing to consider for the rrfpr app and if so, how do you upgrade the electrical to run two pumps?

[Dangerous Ken]

Wire them like a good dual voice coil subwoofer installation.
With a rear battery relocation, it would be really a short run.
Another way is a small car audio sealed cell (2nd battery) back there that's designed for high amp alternator draw, separate from the weak mkII power system. I did this to power several 7 amp shaved door solenoids.

Ken

[makipsee]

u would have 2 run a second supply feed for the second pump

[Funkycheeze]

sounds like a total pain in the ass for extra RWHP the mk2 chassis cant use (not enough room in the rear end, chassis too light)

680s should be plenty large enough for any resonable HP goal

[williamb82]

what im going to do is use a 10awg wire from the distrobution block for my amps and run the fuel pumps off a standard 4 wire relay they sell for fog lights. has 1input and 2 output pins. then use the stock fuel pump power wire to turn the relay on and off. as for your setup with the rrfpr, id run the pumps in parralel. as the volume drops as the pressure rises, in parallel the pumps will double the volum you are currently getting with a sigle pump. in series. they really arnt doing much. they are both flowing the same fuel. itll prolly help some, but imho, parrallel would be much better. that, or buy that exspensive ass fuel pump that is meant to flow high volumes even at extreame pressures. forget the brand name but it was like $400-500 for 1 pump. 2 walbros and the 6an line for the 2nd one is less in price.

[williamb82]

sounds like a total pain in the ass for extra RWHP the mk2 chassis cant use (not enough room in the rear end, chassis too light)

680s should be plenty large enough for any resonable HP goal


how do you figure it cant use it? mkii's have been run with well over 700rwhp. you just have to set it up right just like any other car with that much power.
william

[makipsee]

well i also plan on installing a roll cage and 315 tires but i still have time for that....for 650 hp and 680 injectors is kinda close for me i would feel safer with the 720's so im not working them as hard

[makipsee]

any one know a web site where they sell rim that are 11 to 12 inches wide with the 114.3mm x4 lug offset... a couple of my friends tell me old mustang rims will work but i cant seem 2 find them any little bit will help thanks

[CJSREDPRA]

any one know a web site where they sell rim that are 11 to 12 inches wide with the 114.3mm x4 lug offset... a couple of my friends tell me old mustang rims will work but i cant seem 2 find them any little bit will help thanks

This is in a engine swap forum because???????

<---- Yes I'm being an ass..........

And for your information, 10" wide rims are going to be a stretch..... 11" or 12" wide wheels......Either the back of the tire is going to rub the shocks, or you will need to hack off the fender openings so that you don't have tire rub........

Admins: Someone please move this......

[makipsee]

yea i know its an engine swap forum i know your right but since it was my thread i figured what the hell... and any mods im not 2 worryed about b/c i can do my own custom work

[MWebber]

yea i know its an engine swap forum i know your right but since it was my thread i figured what the hell... and any mods im not 2 worryed about b/c i can do my own custom work

next time... add this: "what the hell, I'll put it in the right place".

thanks,

Moved.

-MW

[makipsee]

i was use 2 supraforums there more lenient in what u post in your own thread

[MWebber]

we don't really give a damn what you post IN your thread as long as it pertains to the organizational structure of the forum.

If you want to post about engine swaps then post in engine swaps....

if you want to post a "general tech" question.... Eurika!

We are NOTHING like stupidforums. Thanks.

[dogstar]

dude... no offence, but get your 2jz in and running before you start worrying about pie in the sky 650hp setups.

ask norbie, its a ton of work, and im sure that 300ish hp will keep you happy for a while, long enough at least until you can research the benefits and drawbacks of a two pump system.

also, this is kind of a general comment, but who in their right mind would swap in a 2jz without doing some freaking electrical upgrades?!?!?!? lol

[drftsupramk2]

- Ah VTEC. All the lag, none of the turbo. It's like waiting for bad sex
ahh shizle dogstar you just made my cry. that is the funniest thing I've heard all day!
and the 2jz on unupgrade electrical system. These car have enough problems as it is overtaxed is putting it nicely!-DonutmasterHLarryous out!

[makipsee]

i have been researching it for about 4 months now i know what the work involves, im researching about the pumps so i know whats to come in time i would rather find out all the problems im going 2 face before i start rather then starting one thing then facing something i know nothing about

[dogstar]

then you already know that compared to the swap, dual pumps is nothing.

[Supra_devil]

I don't see why you want dual pumps. mk4 guys push more power than that with one.
as long as you have a good fuel pulsation damper then you shouldn't have pressure pulse issues.
wiring it is easy, a 30 amp relay and some wire.
but again, get it in and running. run it for a while to see what kind of issues come up, electrical, cooling, drivetrain, etc.
modding after its done is simple.
also, your going from a stock 85 to a 2jz. I do hope your doing suspension and brakes now too. cuz frankly, jumping that much power on stock suspension is stupid, and jumping from stock to even upgraded to a modifyed 2jz imo is kind of silly. unless you have a lot of experiance driving high power cars...

[makipsee]

i am upgrading the suspension and brakes im also going 2 4 to 5 lug conversion, i want 2 have the duals b/c i dont want 2 have 2 worry about issues with lack of fuel and i start modding