RB20 turbo VS RB25 turbo

[judasentinel]

Absolutely right, Skym. I accept my error. I did mean the actuator bulb to be in front and the wastegate (it is actually a gate to be factual) at the exhaust side :-o, both connected by a metal rod.

[Skym]

I used to call it a wastegate until someone mentioned it was an actuator. ops:

[mvs2]

I was just about to request some comparisons vs the rb25 turbo but I believe this thread has answered my questions as well. Iam also in the market for a new turbo but by the looks of it the rb25 wont be quite what im looking for so I will probably look for a good used turbonetics or HKS.


^^^im not a big fan of the ebay turbo's, I saw what one looks like after a years use and it wasn't in the best of shape. I had an old turbonetics on my teg that I ran pretty hard for quite a some time and the sucker was as good as new when we pulled it off.

[J-Ran]

ok....so RB20/25/26 engines are all same blocks by what you say, then i can slap the 26 head on my 25DET and turbocharger from the better of the 3 variants right?

lol

thats not what anybody is saying. He is thinking about taking the turbocharger (just the turbocharger itself) off of an rb25det engine and putting it on an rb20det motor.... so he will have an rb20det enging (yes rb20 block and head) with a turbocharger off of an rb25det because the turbocharger is bigger and can push more air into his rb20....

side note, why be sarcastic like that?

[Skym]

The actuators when used on a stock car are 6psi for RB25 actuator, 8psi for RB20 actuator. Of course that changes when you add intake, exhaust mods. Also I think RB25 turbo doesn't have a nipple on the compressor housing for the air feed to actuator bulb. RB20 compressor housing has a nipple for air feed to actuator bulb.

I like the TD06-20G turbo kit (230rwkw or roughly 373hp at engine in the videoclip below with stockish RB20 motor) -

http://www.youtube.com/watch?v=dKcqwovVnZw

[89Baysideblue]

on both my stock and aftermarket guages indicate 7PSI on the RB25?

[Skym]

Stock R32 boost gauge is not in psi, it's x100mmhg. Max on stock boost gauge (7 x 100mmhg = 700mmhg) is roughly 13.5psi.

[89Baysideblue]

now ya lost me mang? hehe!

on my Autometer boost guage reads 7 PSI aswell as the OEM guage (whatever that read in im not sure?) but im running the RB25DET basically stock trim exception of BOV, APEXi power intake?

besides....it cant be like 13+ PSI anyhow, i thought 12 PSI was Max you want to apply on stock ceramic wheel?

im lost! ops:

[89Baysideblue]

thats not what anybody is saying. He is thinking about taking the turbocharger (just the turbocharger itself) off of an rb25det engine and putting it on an rb20det motor.... so he will have an rb20det enging (yes rb20 block and head) with a turbocharger off of an rb25det because the turbocharger is bigger and can push more air into his rb20....

side note, why be sarcastic like that?

just ran across this one...
im sorry i came across this way, however....it was a question not sarcasm!
seriously, if i have an RB25DET block, by what was said i can install the RB26DETT head then whatever the best turbo was aswell?

again, sorry man.

[Skym]

Auto meter boost gauge is PSI (Pounds per Square Inch).

Stock R32 boost gauge in the top left corner of dash uses mmhg. Basically it means mm (millimeters) hg (mercury).

If you look in the right bottom corner of stock boost gauge, it has x100mmhg. That means you X the reading on the boost gauge by 100.

So 7 (max on stock boost gauge) x 100 = 700mmhg

and 1mmhg = 0.01934psi

So 700mmhg x 0.01934 = 13.538psi

You could fit the RB26 head on RB25DET bottomend, but it probably would be easier to buy a stock RB26, fit a single turbo to it,
as you'll probably end up upgrading the bottomend to RB26 spec.

The 2500R (very rare prototype R33 25T built by Nismo with a 450hp RB25DET engine) used a RB25 head, RB28 bottomend (I think the 2.8 litre bottomend is the same bottomend as used in the R33 400R, which is the road spec version of the Lemans spec R33 GTR racecar). There's one of these 2500R's in Australia at the moment. I think it has been slightly modified from the original Nismo specifications and now produces around 480hp.

Here's what the 2500R looks like -

http://www.skylinesaustralia.com/forums/uploads/1166673328/gallery_9783_1516_38885.jpg

http://www.skylinesaustralia.com/forums/uploads/1166673328/gallery_9783_1516_51362.jpg

Also it has the Omori factory id badges, etc.

[89Baysideblue]

wow! thanks!

reason i ask is when i had a POS daytona by swapping certain things meant for a better engine overall and also gains in HP. like swapping out the rocker head for the roller head from the newer daytonas, etc....

just was curious.