What is QR25DE stand for?

[SuperTurbo]

For Sentra's engine, what is that QR25DE, QR25HO, MR20DE

(What is QR, HO, and MR stand for?) ex. 25 is the engine displacement, D= DOHC......

[spddemon]

I think its just the engine code. Nothing special

[nissantech06]

For Sentra's engine, what is that QR25DE, QR25HO, MR20DE

(What is QR, HO, and MR stand for?) ex. 25 is the engine displacement, D= DOHC......

The first two letters are the block code. The numbers are the displacement. The last letters signify igntion type, supercharged, turbocharged or nothing, distributor or not, etc.

QR- block type25- displacementDE- distributorless ignition

Another example:

VG- block type33- displacementER- distributor, supercharged

[SuperTurbo]

The first two letters are the block code. The numbers are the displacement. The last letters signify igntion type, supercharged, turbocharged or nothing, distributor or not, etc.

QR- block type25- displacementDE- distributorless ignition

Another example:

VG- block type33- displacementER- distributor, supercharged

I understand that, but what is QR, MR, VQ mean?

I know RB = Race build = strong block, ready for some mod

[nissantech06]

I understand that, but what is QR, MR, VQ mean?

I know RB = Race build = strong block, ready for some mod

They are just the block types...they don't really have any particular meaning as far as I know past the mechanical design.

[nametakennow]

RB does not mean race build, it's just a designation they use for different generations of engine.

DE is not distributor-less ignition.

D - Dual overhead camE - Electronic fuel injection

For instance, SR20DE's (and DET's, and maybe even VE's) have a distributor.

[nissantech06]

RB does not mean race build, it's just a designation they use for different generations of engine.

DE is not distributor-less ignition.

D - Dual overhead camE - Electronic fuel injection

For instance, SR20DE's (and DET's, and maybe even VE's) have a distributor.

Ah, yes...I forgot...

If you google engine codes for Nissans, it will land a couple of websites that explain them all.

[GetThatThingISentra]

The first two letter just designate engine series, with the V prefix indicating piston orientation (like a V6). The next two numbers are displacement, which are the easy parts. From then on, there are a few different designations for the letters assigned afterwards:

1) The first letter designates the valvetrain of either a D or a V, where D=dual overhead cam and V=variable valve lift. If there is no D or V, your engine has a single overhead cam.

2) The second letter deals with your fuel delivery with E, i, or D, where E=multiport fuel injection, i=throttle body fuel injection, and D=direct injection. If you have none of these, your engine has a carburetor.

3) Finally, if you have a 3 letter, it lets you know the type of forced induction your car uses, either T for turbo or TT for twin turbo.

I found this information at SE-R.net and it was pretty useful. I know I feel better educated about my fantastic QR25DE engine (QR series, 2.5 liter displacement, dual overhead cam multiport fuel injection!)

[philipa_240sx]

You only missed one:

3rd letter: R = Supercharged

ie. The VG33ER used in the supercharged Xterra and Frontier

Nissan has also broken with convention on with the VQ35HR (350Z, G35)and the VQ37HR (G37). HR = High Rev, High Response

[VMPhil]

I know I feel better educated about my fantastic QR25DE engine (QR series, 2.5 liter displacement, dual overhead cam multiport fuel injection!)

Coming from a Fellow QR owner, im sure there are alot of people who have other choice words for the QR other than Fantastic. mines is still running strong though *knocks on wood*.