Hey, I know this has been asked over and over again but I need a little more info and I don't think the search will bring it up. I have a '99 GSR with a HP Racing intake manifold and a custom turbo kit (T3/T4). I want to boost about 9-10psi on it and need to know the calibration for the FMU with the 310cc injectors, is it 8:1 that I need to use?

What should I set my idle fuel pressure at with the 310's, 8:1 FMU, In-line pump, and stock in-tank pump with about 9-10psi?

And with that manifold being on the car, do you all think I might lean out to much up top with this fuel setup?

What kind of WHP can I expect out of this at 10psi?

I would have a Hondata but I won't be able to afford it for about another 2 months or so, please don't flame me for this. Thanks

 

I use an 8:1 disk w/310's and it works fine. About the fuel pressure, I have a stock regulator and use an AFC to lean it out at idle.

 

At the risk of being a Nube...I'm going to have 290cc's and running upwards of a whopping 6-7psi...do I even need an FMU? Personally, they seem a bit sketchy to me, especially since I'll have a stock fuel pump. I was thinking of boring out the fuel rail (maybe doubling the volume?)...would that do me anything significant?

 

I'm no expert but I would say no.

 

anyone else have opinion?

 

if you go with 310s, 8:1 is the way to go. alot of the guys on here would say so.

 

Even you you don't like them,Not having one is 100x's worse then having one and not liking it.You don't need one if you don't care for your engine.Honestly even at 2psi you will need one.You will need at least (bare minimum) a 12:1 fmu (stock injectors) high pressure fuel pump.The stock pump will lean out after about 4psi of boost (with a fmu).If you run the 290cc injectors you could use a 10:1 or 8:1 fmu.Boring out your fuel rail will do nothing for you.Even though you have 2x's the fuel sitting behind the injectors it will do nothing for you if it cant get past the injectors (into the combustion chamber) in higher volumes.

 

I would say use a 6:1 fmu if your going to run stock idle fuel pressure.i tried to run a 8:1 with my 310's but around 5,500 rpms they would just flood my engine with fuel.I now have 6:1's and i'm about 1/2 way in the rich area of my air/fuel gauge and the car runs a lot better.

 

Oh and vortec even recomends using the 6:1 with 310's

 

so why does everyone use an 8:1 with 310's if it floods out and Vortech recomends a 6:1

 

Richer is safer, but too rich and power goes down.

Use the 6:1, adjust idle pressure down about 5psi and you are set. Get and EGT and A/F to make sure.

Randy

 

So what is the idle fuel pressure on the GSR? Then I just take 5psi out of that and use a 6:1 disk?

Am I going to run lean on top end with the 6:1 with the 310's and taking 5psi out of the idle pressure?

 

I plan on running a max boost of 10psi on race gas. Will this be OK?

 

Hmm...now that I think about it the fuel rail won't help much, but I'd think it would give some benefit, just having more fuel past the filter...probably not worth it to get it done, though.

 

Anyone run 10psi on pump gas and the 8:1 or the 6:1 FMU and 310's with in-line pump and stock intank pump?

What is everyone running with the FMU, Injectors and how much boost?