Rb25de Neo Head Differences

[R30gtN/A]

Hey people I just thought I would post this up to show you and to get your thoughts on using a Neo head for a RB30DET? here are some photos to show the differences between R33 early 25DE and Neo 25DE heads. And maybe this could help update the PDF?

Neo head with a R33 25DE head gasket sitting on

Neo head with R33 25DE intake gasket on it

Neo intake with R33 25DE intake gasket on

Neo piston

R33 25DE head with Neo intake gasket on

Neo chamber

R33 25DE chamber

Both manifolds side by side

Edited August 23, 2009 by R30gtN/A

[allthewaytotheskyline]

so which is which?

[R30gtN/A]

Sorry I just labeled them!

[R31Nismoid]

Well going by the pics you certainly wouldn't use a NEO-DE head

The intake ports are terribly small

[R30gtN/A]

Yea I was thinking the same thing, im just thinking of making a thrasher or a n/a RB30DE or something as its not for my car as I allready have a RB30DET built. So does anyone know if the turbo heads are different?

[Spoolup]

The DE head has much smaller intake ports than the turbo head - The NEO turbo head has the same size intake, exhaust ports and valve as the R33DET head.

[R34GTFOUR]

I wonder if the N/A neo head can be extensively ported to the turbo spec? ie if they are the same casting, one with smaller ports.

Only ask because i have a na neo head that i was going to use but i didnt expect that the ports would be different. I thought nissan kept everything the bloody same, at least they did with the r33 heads..

[R34GTFOUR]

Also is there any chance that head is a rb20 neo head?

Still find it hard to believe that the neo's are different between na and turbo, nissan is normally lazy and have the same parts for everything

[R30gtN/A]

Yes defanatly a RB25DE! Im pretty amazed myself

[MBS206]

Can you do a better photo with the Neo head, with the 25 head gasket on it?

Mainly straight on, not on an angle, even if it's just one cylinder.

From that angle it appears like a 20DE head.

[lcxu105]

R34 de head cast number is 5l7 and 34 det head is 5l8 for the neo's.r33 det head is 75t and the dett is 05u for 32 33 34 and the de head is same for 32 and 33's 08u

Edited January 11, 2015 by lcxu105

[ADH_A31]

are all those type of RB25 use the same block 75t?

[ADH_A31]

and can I make conversion from 5L7 to 5L8 neo's ? 

[Junior1ne]

Yeah all the same(ish) block, there are differences between turbo and non turbo blocks but only for oil feed and drain for the turbo and same for water.

 

Yes you can put a Neo DET head on a Neo 25DE block so long as you sort out the issues mentioned above.

Im doing the same thing right now.