Rb25det s1

[Jackabo]

Hey guy I’m building a Rb25det s1 with a forged and balanced bottom end . I’m aiming for about 350-400rwhp. was just wondering how much the stock Rb25det s1 head can handle in regards to rev change and hp and if it’s worth changing to solid lifters

also if anyone has any info on better springs and and valves

[Murray_Calavera]

You could make that power with an unopened motor. 

If all you are doing is adding forged pistons and rods, then there's no point in revving it higher then stock. 

I don't know if you've looked into how much it costs to convert to solid lifters, it's not a simple job and I'm sure the cost would terrify you. You'd be better of selling your motor and buying a NEO long motor. 

Why do you want solid lifters and upgraded valves for a 400hp motor?

[Jackabo]

I’m aiming for 400hp at the moment so that later on one 400hp gets old I can just change over the supporting mods and not have to crack open the engine again

[GTSBoy]

Oiling mods more important than ANYTHING else.

[Murray_Calavera]

Agreed, oiling mods over everything else. 

Are you going to be personally building this motor? 

[Jackabo]

I am personally building the motor I’m installing a nitto oil pump/crank collar, head drain and oil restrictors Along with the head 

can I use the stock sump with all that?

[GTSBoy]

1 hour ago, Jackabo said:

head drain

Please tell us that you have read the oil control thread. If you have no, then you have circa the last 100 pages of it to read before you proceed. No whining, no pissing, no moaning. Just do it.

[Murray_Calavera]

13 hours ago, Jackabo said:

I am personally building the motor I’m installing a nitto oil pump/crank collar, head drain and oil restrictors Along with the head 

can I use the stock sump with all that?

"can" you? Yes. Should you, probably not. I would not use a stock sump with a nitto pump due to the increased flow, I'd want more volume to back it up. I'd look at getting an enlarged and baffled/gated sump. 

If your building this yourself, have a chat with your machinist about your long term goals and what they recommend to support that. Hopefully your using a machinist that has worked on hundreds of RB's and knows them inside out.