How Much Is The 25De Capable Of?

[Tumic]

Ok here is the deal:

I live in Sweden and have a 33 4dr that i currently building a 30/26 with about 550-600whp on E85, so with that said i allready have a high power RB in progress.

But i've also have a Nissan 180zx, or as you call them silvia s12 and gazelle, currently with a ca18et sitting in it.

The thing is that i have a rb25det sitting in the garage, and have got my hands on a NA head with cams and NA pistons.

I have a thing for NA engines and thinking about swaping the pistons and head on my 25 and going for a

NA build, i also have a set of 26 ITB's laying in the garage.

The big question is how much have been taking out of the 25na's? Im talking with cams, ITB's, etc.

When im looking at the dyno page i see mostley stock engines with pod filter and exhust, not fully built engines with cams etc.

Is there someone who have dynoed about 250whp out of a 25de ? In Sweden the BMW m50b25 engines is fairly popular and making Good power with fairly small mods.

Im well aware of the costs of a NA build and im doing it for the sound and soul of the engine, not for high power build, i just want to know best options on cams etc and best way to make 220-250 whp ish.

My basic setup in my head would be:

*25det rods

*25de pistons

*decked 25de head

*25de cams regrind or larger det cams

*rb26 ITB's

*custom exhaust manifold

*aftermarket ecu

When does the stock valves come in to restriction? Etc..

The car will recive a s13 rear subframe so i can get a 4.3 or 4.6 final gear for it, and i will roll on 195/45/15 so it's no wide tyres it will need to spin, the car will act as a street drifter so i want the nice NA sound and a fun powerband.

Any Good links to "high power 25de builds" and info would be appreciated.

//Jesse

[-Jimmy-]

There isn't much out there, especially on this forum. How would you go about fitting the RB26 ITBs on the RB25 head? I know there are adapter plates available but not so easy to find any fairly expensive.

I'm sorry my reply wasn't helpful.

[Skepticism]

Off topic, but please do a SR20VE build instead. I'd love to see a gazelle with one of those in it.

Edited September 28, 2014 by Skepticism

[DJBarnstar]

You would think that compression is the main thing.

If you can get it close to 12:1 + you should make that kind of power.

[Ben C34]

Cams are the main thing.

[WYTSKY]

The closest I could think of is Greg_R31's old build which was an NA 26/30. Was work of art. one of his posts said power wise was: 225hp/ 167.8kw at 8200rpm that was back in '11, can't remember if it went up from there. I'm pretty sure he sold it since then but thats the closest I could think to what you are asking.

Anyway have a read of his build thread. Had ITB's too. http://www.sau.com.au/forums/topic/374496-gerg-r31s-na-rb2630de/

As for stock valves becoming a restriction my unopened 25DE+T is still putting out nearly 300rwkw on stock pistons/rods/head. Hope that helps, good luck with the build.