Rb20det Afm

[1990 GTS-t m]

hi guys n girls.

How many rwkw is the standed rb20det afm good for?

I have a r32 gtst with vg30 turbo, fmic, gtr pump, fuel reg & safc 2. Got 2 get some gtr injectors next and was woundering if i need to ght a z32 afm at the same time...?

thanks for your help:D

Edited February 6, 2006 by 1990 GTS-t m

[TTT]

I'd say not much more than 200rwkw...

it seems the RB25 afm (which has same resolution as rb20) allows tuning on the Rb25 up to about 220rwkw.

considering you would need more boost (air in) in an RB20 to do it, 200rwkw is a good guess.

you would probably get close to 200rwkw with those mods at about 14-16 psi of boost.

[1990 GTS-t m]

thanks,

i hope to get ova the 200rwkw mark but it sounds like i mite have to start looking at a rb25 turbo to do so.

[TTT]

vg30 turbo is bigger than rb25..

[1990 GTS-t m]

Yeah thats what i would have thought but i read this & it sounds like i would be beta off with the 25.

"The VG30DET BB turbo really is not suited to the rb20. It is much better suited to a large capacity motor that requires a free flowing hotside.

It runs the same chra as the R32 rb20; meaning, the compressor wheel and turbine wheels are exactly the same.

The only difference being, the vg30det bb turbo runs larger compressor and turbine housings.

The rb25 turbo is most definitely an upgrade, it runs the same sized turbine housing as the rb20, (from what ive measured) but has a larger compressor and compressor cover.

The R34 RB25 turbo runs exactly the same larger vg30 turbine housing, with the larger comp cover and larger compressor."

[TTT]

Both the wheels of the rb25 turbo are bigger than the rb20 ones.

I measured them when I upgraded my last rb20.

[nytrda]

hi mate there was a topic on this not so long ago. with SYDNEYKID having this to say on them

There is not a black and white answer to this question. Just because the AFM reaches 5.1 volts output doesn't always mean it has to be changed

The only time you really need an AFM upgrade is when unanticipateable changes in airflow occur, ie; not linear with rpm changes. At high rpm (ie; past boost build and camshaft timing effects) this shouldn't be an issue. The fuel and ignition requirements are satisfactorily driven off the rpm change.

Keeping the above in mind, I have seen an RB30 run quite happily on an RB20 AFM at 265 rwkw. I have also had to change an RB25 AFM at 225 rwkw because the airflow changes where unpredicable (ie; not linear with rpm).

I hope this helps you. As i am currently hoping my set up makes 220 an i will be using the standard afm which is a rb20 one.

Cheers Jamie

Here is the other post. http://www.skylinesaustralia.com/forums/in...opic=102519&hl=

[1990 GTS-t m]

hey thanks for that am gona take that all on board and just see where the stock gets me.