rb25 swap question

**BongRips** · 09-09-2011, 06:33 AM

So I decided to go a different direction with my build and install an rb25det into my r32 gtst in the spring. I already have an upgraded turbo going onto my rb20 to replace my blown one that's good for ~450hp which I'll be swapping onto the 25. I'm trying to make a supporting mod list to get an idea for prices. I've taken a lot of the unnecessary stuff off like the front facing plenum as that can come later to improve responsiveness. Car has the turbo, fmic, divorced dump pipe, decat, cat back, hks style intake, and an hdi ebc. In the spring I'll be doing the swap with a down pipe, yellow jacket coil packs, haltech ecu, 660cc DW side feed injectors (will be sold and swapped for top feeds once I do plenum, TB, and fuel rail), 300lph DW fuel pump, and stage 3 clutch with light flywheel. That's what I will be buying over the winter and having installed in the spring. I will be able to afford more early-mid summer, possibly sooner. Is there anything I should get or that I'm missing to handle ~400whp on an rb25 engine and tranny

**whiteboy87** · 09-09-2011, 12:40 PM

other than the basics for the rb25 swap ie modifying the speed sensor and having to get either a custom drive shaft or the rb25 yoke welded to the rb20 driveshaft you should be good. with any motor swap changing the water pump, tbelt, tensioner and idler pulley wouldnt hurt. plus if your planning on upping the boost id replace the headgasket and headstuds too.

**r33_gtst** · 09-09-2011, 02:39 PM

Only thing your missing is fuel pressure regulator and wastegate. What manifold are you using?
List looks about complete
I squeezed 492 rwhp and 364 lbft torque from my rb25. You should do 400 rwhp EASILY with that halted ecu and a good tuner.
Here is a vid of my car and it also has the mod list

http://www.youtube.com/watch?v=y_ImD...e_gdata_player

**BongRips** · 09-09-2011, 03:22 PM

Oh yea, totally forgot fpr. It's an internal wastegate turbo so I don't need to actually get one

I am using stock maniifold btw

**r33_gtst** · 09-09-2011, 03:52 PM

The set up sounds good. I'd spend a bit of $ and get a new manifold that flows better. My oem rb25 manifold when taken off is so much more restrictive than a flowing 304 stainless steel manifold. If your spending that much time and $ I'd spend a bit more and upgrade. Then the set up is complete

**cschepp** · 09-09-2011, 03:55 PM

Stock turbo won't last long on those numbers and will limit the cars potential if your staying stock

**BongRips** · 09-09-2011, 04:01 PM

When did I say I was using stock turbo? :s I said I have an uprated turbo thats good for ~450hp and that's why I'm asking if these mods will support it. @r33, I will be doing manifold upgrade eventually. I am doing my car in stages. This spring is the engine and tranny swap with coil packs, fuel system upgrade, and the other minor things. I will be doing new manifold, plenum, cams, etc the year after though. I got ****** over a while ago and now I'm in debt and trying to get out of it but I'm still about to afford about $7 or $8gs in the spring though which should cover my parts list and install/tune. Throughout the summer I'll be able to add more, but I'll probably save it for the winter to save up again and do a big overhaul again. The set up probably won't be "done" for a couple years, but I should be making big numbers fairly reliably in the end.

**r33_gtst** · 09-09-2011, 04:16 PM

Right on man
If your looking for a quality affordable manifold, STEC makes a top mount and side mount that is pretty decent. I've had no issues with my top mount, was like $350 and I've been throwin 20 psi at it for a year and a half no issues. Flow will be much better and less restrictive, better response and power #'s

**BongRips** · 09-10-2011, 06:27 AM

Should I go for the S1 rb25det or the NEO? I read that the stock NEO makes 280PS (276hp) like the rb26, that can't be true can it? And would there be a significant difference in the performance? I know the neo has solid lifter as opposed to hydraulic, but I will eventually doing a full internal build and if I had the S1, I wouldn't mind spending money on new cams, valves, lifters, etc. So would it really be worth it to spend the extra money on a neo when I can get an s1 engine and tranny and everything for 1600 if I am gonna be building the internals?

**r33_gtst** · 09-10-2011, 11:15 AM

Go S1
They are cheap, reliable, and available
Just as capable of power as the 26. Just ask angel at KOE about his rb25 from the depths of hell
Can't believe a full rb25 set up is like $1600 here in Canada and Honda swap is $3k-6k lol.