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Hi Guys,

1st-

I would like to know how much power can be produce of each of the fuel system components, ie. how much power the fuel rail, fuel pump and injectors can handle individually

2nd-

I would also like to know what mods I would need to get to reach my first goal 250-300rwkw, Preferably 300rwkw

I am currently producing 195rwkw

I have

-Power FC

-High flow intercooler

-High flow exhaust

-Greddy intake manifold

-Greddy radiator

-Greddy oil cooler kit

-splitfire coilpacks

-Gizzmo boost controller

I also have a wet NOS kit (50-100HP) but it is not installed

and soon to get Nitto drag metal head gasket

Hope you can help guys

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https://www.sau.com.au/forums/topic/328249-stock-fuel-system-power-package/
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Ok first thing, head gasket. Don't bother replacing it, why would you?. If anything you want a stock headgasket since it can potentially save your engine by blowing the gasket first.

For the stock fuel pump, realistically anything over a stock turbo it should be replaced. Hell even with it's given age it should be replaced. Read this thread regarding the stock fuel pump, few good explanations there:

http://www.skylinesaustralia.com/forums/Po...mp;hl=fuel+pump

For the injectors people say different power levels since some qoute stock fuel pressure limits, others bump up the rail pressure to squeeze a bit out of them. As a rule of thumb, I think people see a high injector duty cycle around the 220-230rwkw mark. As I have said, some people say different things. But for your power goals you gotta change them anyway, so just go for something around the 740 mark if you are planning on over 300rwkw. Personally I wish I had gotten the Nismo 740s over the Nismo 555s for the extra head room.

Fuel rail don't bother at the power levels we are talking other than if you wan't a nicer looking one.

Now for the power goal, are you talking with the nitrous, or without? Because that is going to be a big difference in recommendations.

In essence you have all the right ingredients all ready to go on the car, just comes down to turbo choice.

Remember though, at the 300kw mark the RB25 bottom end is at a high risk of letting go.

Edited by PM-R33
Ok first thing, head gasket. Don't bother replacing it, why would you?. If anything you won't a stock headgasket since it can potentially save your engine by blowing the gasket first.

For the stock fuel pump, realistically anything over a stock turbo it should be replaced. Hell even with it's given age it should be replaced. Read this thread regarding the stock fuel pump, few good explanations there:

http://www.skylinesaustralia.com/forums/Po...mp;hl=fuel+pump

For the injectors people say different power levels since some qoute stock fuel pressure limits, others bump up the rail pressure to squeeze a bit out of them. As a rule of thumb, I think people see a high injector duty cycle around the 220-230rwkw mark. As I have said, some people say different things. But for your power goals you gotta change them anyway, so just go for something around the 740 mark if you are planning on over 300rwkw. Personally I wish I had gotten the Nismo 740s over the Nismo 555s for the extra head room.

Fuel rail don't bother at the power levels we are talking other than if you wan't a nicer looking one.

Now for the power goal, are you talking with the nitrous, or without? Because that is going to be a big difference in recommendations.

In essence you have all the right ingredients all ready to go on the car, just comes down to turbo choice.

Remember though, at the 300kw mark the RB25 bottom end is at a high risk of letting go.

+1 on everything except the last sentence

Stock Rb25's are ok to 500hp at the wheels if revs are kept to sensible levels

And providing you get it tuned by someone who knows what the f**k they are doing

Thanks, For the advice on the fuel, With the nitrous i was think 300rwkw before nitrous (maybe 475HP with nitrous), I have to replace my head gasket because It has popped a water channel out under the exhaust manifold (not really sure why there was pressure in the water channels anyway)

Ok first thing, head gasket. Don't bother replacing it, why would you?. If anything you won't a stock headgasket since it can potentially save your engine by blowing the gasket first.

For the stock fuel pump, realistically anything over a stock turbo it should be replaced. Hell even with it's given age it should be replaced. Read this thread regarding the stock fuel pump, few good explanations there:

http://www.skylinesaustralia.com/forums/Po...mp;hl=fuel+pump

For the injectors people say different power levels since some qoute stock fuel pressure limits, others bump up the rail pressure to squeeze a bit out of them. As a rule of thumb, I think people see a high injector duty cycle around the 220-230rwkw mark. As I have said, some people say different things. But for your power goals you gotta change them anyway, so just go for something around the 740 mark if you are planning on over 300rwkw. Personally I wish I had gotten the Nismo 740s over the Nismo 555s for the extra head room.

Fuel rail don't bother at the power levels we are talking other than if you wan't a nicer looking one.

Now for the power goal, are you talking with the nitrous, or without? Because that is going to be a big difference in recommendations.

In essence you have all the right ingredients all ready to go on the car, just comes down to turbo choice.

Remember though, at the 300kw mark the RB25 bottom end is at a high risk of letting go.

I reckon I will probably get a set of forgies ready so that i can eventually go over the 500hp mark when the time comes

+1 on everything except the last sentence

Stock Rb25's are ok to 500hp at the wheels if revs are kept to sensible levels

And providing you get it tuned by someone who knows what the f**k they are doing

lol at "won't" instead of want.

do a search . go read the dyno results thread

Fixed mother f**ker :yes:

+1 on everything except the last sentence

Stock Rb25's are ok to 500hp at the wheels if revs are kept to sensible levels

And providing you get it tuned by someone who knows what the f**k they are doing

I'll hold you to that :) haha. But yeah I know what you mean.

Edited by PM-R33

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