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Discussion Starter · #1 ·
Just looking for opinions on what way you guys reccomend to fuel a fpp kit running around 8-9 lbs of boost. My bud is getting his sled back together soon and he wants me to find him a new way to fuel it, apparently he cant get the motec for a little bit so he wants something to get him through the season thats better than the dobeck box. We had the thing almost all the way maxed out for fuel when he was running 6 lbs and it was still cruising around 14/1 but ok wide open, hes worried with more boost we wont be able to get enough out of the dobeck box. Btw we are rebuilding it with low comp weisco pistons and a set of falicon rods that fpp hooked him up with, its also getting punched out 20 over, we should have the block back by monday. I guess over the summer hes bailing on the fpp kit and getting a full set up from martin up at precision, hes just a tad impatient so he wants me to get him through the season which is maybe 2 more weeks. Any advise or thoughts? Thanks
 

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boost junkie
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rb3/rbr with bigger injectors
 
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Discussion Starter · #3 ·
rb3/rbr with bigger injectors
He was eyeballing that rb3 for sale in the classifieds, i pm'd him and he reccomended the same, going up to 750cc injectors. Where would we find those? Anywhere states side to get them? He wanted me to call fpp and ask them about that but im betting they will just reccomend staying with the dobeck box
 

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ride hard or die trying
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Many here back In the day have used fpp's stage 2 kit.

Set the box to 1.1.1.4 and your good to go.

I never had a problem with the dobeck box like others have posted.

And get the new a/f gauge thing from dobeck.

The other options is 255 seadoo injectors. Powercamander pti, auto tune, pod 300 display.

And fab up a way to put the sensore in the stock location.

Pull 33% fuel as a start
 

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So whats the minimum lbs for injectors we would want to say run a max of 10lbs of boost? What does the stock ones put out? I see those 255 seadoo ones arent expensive but i found some that say they are either 42lb or 50lb
 

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Get that rb3 out if the classifieds, have the stock injectors drilled to 700cc's and I can send you a map that my buddy has been running for 4 years at 10lbs.
 

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boost junkie
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stock injectors are 320cc

I have a good set of 650cc @ 58psi injectors to sell (good to about 300hp)

they have been flow tested and my injector guy said they were good to use

they were modified by powderlites and they need a new home
 

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This is just my experience with bigger injectors and a power commander pti. In my opinion the best way to fuel 8# boost is with stock injectors and a rising rate regulator. I used several different sets of bigger injectors and it was maddening. I could get them dialed in on any particular day but when the temp changed the setup would be all wrong again. For a short term test until his motec shows up just raise the fuel pressure until the air fuel ratio is good at wide open. I have a good power commander pti with a low boost turbo program in it if sell for $200.
 

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Can anyone reccomend a good fuel pressure regulator? Im assuming he should add a different fuel pump too?

I also see those seadoo 255 injectors are pretty cheap so that may be a good route for him to go? Idk
 

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boost junkie
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rasing the fuel psi with the stock wimpy fuel pump is asking for trouble
 

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I ran a 1:1 rising rate so at 10# boost depending on temp it would put you at 68# fuel pressure. Never had a fuel pump issue. Once the sled got warmed up I would make a short wide open pull while checking the air fuel ratio then dial up or down on fuel pressure to get it to low to mid 11's then ride it.
 
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I ran a 1:1 rising rate so at 10# boost depending on temp it would put you at 68# fuel pressure. Never had a fuel pump issue. Once the sled got warmed up I would make a short wide open pull while checking the air fuel ratio then dial up or down on fuel pressure to get it to low to mid 11's then ride it.
Exact system I run with exception of additional fuel pump also. Flawless for 10,000 miles.
 

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So whats everyones preferred regulator?
I have a magnafuel regulator but I took it off. Keep it simple and run bigger injectors and a good map. Much easier on the stock fuel pump and less clutter under the hood plus it's only short term right? Why buy parts he doesn't need with the motec?
 

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Discussion Starter · #20 ·
Well hes parinoid about it going down again. Heres whats going on, he bought the mcx box and seadoo injectors from joker today. We were kind of thinking he should add the regulator to help control the afr readings just a litte without changing the map, the box has a 10psi map in it for a stock engine, we are putting low comp pistons in it and a new set of rods. Are we thinking right there? He asked if we could do anything without messing with the map in the box
 
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