Need Help! Difference Between Rb25det And Rb25de

[Judasentinel666]

Hi there.

I am curious to know what differences, if any, exist between the internals of RB25DET and the RB25DE (N/A). I am currently running an RB25DE with a turbo on it, but due to higher compression, cannot run more than 10psi of boost.

I have been informed that the internals of the RB25DE are WEAKER, not made of the same material as the RB25DET, and since the compression of the motor is higher, I cannot run more boost, which also means that I am limited in my options for upgrades to get more power out of that motor. My RB25DE also does not have oil squirters in the pistons. I didnt know that there were oil squirters in the BR25DET pistons.

So, my issue is as follows:

I can EITHER buy an RB25DET (full motor), OR change the internals on my RB25DE to make it the same as, or better than, an RB25DET. All I want to know is that if I want to run more boost (like 15-20 psi or 1.4 bar) on my car with the N/A motor, what all do I have to change inside of it? And how do I go about doing it? What pistons, crankshaft, camshaft, etc., is recommended? Do I keep the same head and valves or d they need to change as well?

Please help me, I desperately need someone to guide me here.

[joeyjoejoejuniorshabadoo]

Hi there.

I am curious to know what differences, if any, exist between the internals of RB25DET and the RB25DE (N/A). I am currently running an RB25DE with a turbo on it, but due to higher compression, cannot run more than 10psi of boost.

I have been informed that the internals of the RB25DE are WEAKER, not made of the same material as the RB25DET, and since the compression of the motor is higher, I cannot run more boost, which also means that I am limited in my options for upgrades to get more power out of that motor. My RB25DE also does not have oil squirters in the pistons. I didnt know that there were oil squirters in the BR25DET pistons.

So, my issue is as follows:

I can EITHER buy an RB25DET (full motor), OR change the internals on my RB25DE to make it the same as, or better than, an RB25DET. All I want to know is that if I want to run more boost (like 15-20 psi or 1.4 bar) on my car with the N/A motor, what all do I have to change inside of it? And how do I go about doing it? What pistons, crankshaft, camshaft, etc., is recommended? Do I keep the same head and valves or d they need to change as well?

Please help me, I desperately need someone to guide me here.

i wouldn't put 15 pounds through a stock DET either...

and esp for 20 psi... you'll need forged internals on either

[Krishy]

stock i think its ok to run 1 bar but not for long....anything higher then that you will need some internal work done like forged pistons and stuff.....running more then a bar is really bad for the stock turbo.....so i say upgrade the internals or your current motor and see how it goes....i guess which options would be cheaper/better suited for you!

[NISZILA]

With the higher compression ratio, i wouldn't be running more than 7psi... unless you want things to go BANG!!

To change the compression ratio, get a really think gasket... this will lift the head and make the compression ratio less. Then you can increase boost a bit more safely.

As the others have said... I wouldnt't run the numbers you're taking about on a stock engine...

To better answer your question... what other supporting mods have you got... or is your engine totally stock with a turbo wacked on and the boost cranked?

[steelmanac]

Are you running an R32 or an R33 RB25DE ? I'm not sure about the internals of the R32 block. The R33 DE crank and rods are the same as the DET. The pistons have a hair larger dome, and are not really strong enough to support a lot of boost. The DE heads have a slightly smaller combustion chamber, but are otherwise identical to the DET. DE compression ration is 10:1 as you know, but that is fine for a turbo car that is well tuned. Most people reduce compression ratios for ease of tunning, and to reduce the risk of detonation. Detonation kills, but with proper tunning higher compression makes a ton of power.

[ssshonky]

dont forget though that the higher compression motor should make MORE power than the equivalent boost on a DET motor. So running 7psi thru a +T conversion will net you more power than 7psi on a standard DET motor.

I have always been of the school of thought that going a DET motor straight up is going to be a hell of a lot easier than doing a bolt on turbo. But mind you done correctly a +T motor can give you good reliable power day in day out .. just need to be realistic about how much HP you want to get out of it.

Are you running an R32 or an R33 RB25DE ? I'm not sure about the internals of the R32 block. The R33 DE crank and rods are the same as the DET. The pistons have a hair larger dome, and are not really strong enough to support a lot of boost. The DE heads have a slightly smaller combustion chamber, but are otherwise identical to the DET. DE compression ration is 10:1 as you know, but that is fine for a turbo car that is well tuned. Most people reduce compression ratios for ease of tunning, and to reduce the risk of detonation. Detonation kills, but with proper tunning higher compression makes a ton of power.

Edited September 12, 2007 by ssshonky