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Fs: R34 Rb25de Neo Head (never Mounted, Mint!)

John M
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John M Apprentice

John M

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I bought this head for $320 USD for my R34 GTT thinking it was a DET neo head. It was purchased from a gentleman in okinawa japan and i had it shipped to the US. I had the head machined to the proper specifications, with the following performed:

-Clean

-Pressure Check

-Valve Job

-Solid Lifter Adjust

-Re-surfaced

Which totalled to $498 USD. Now, i have no use for this head, and have invested over $850 USD into it. I am just trying to get back some of the money so that i can re-purchase the proper head. If anyone is interested, Please send me an email, or PM.

I need to move this head asap. Thank you all for looking. I will post pictures up within a few days when i can.

-John M

[email protected]

R34GTFOUR Mentor

R34GTFOUR

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why?

there is no physical difference between the det and de neo heads, even the cams are the same. The only thing that might be different is the springs and it wouldnt cost much to replace those.

John M Apprentice

John M

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why?

there is no physical difference between the det and de neo heads, even the cams are the same. The only thing that might be different is the springs and it wouldnt cost much to replace those.

I assure you that i know it is physically different or else i wouldnt be in this dilemma of selling the head.

I picked up the newly machined head from the machine shop with a bill totalling $498. I went to put the head on and realized it is not the correct head. The intake manifold ports are very different and the overall diameter of the ports is a lot narrower than my previous head. The intake manifold from the R34 DET neo will not bolt onto the head

ORIGNAL NEO HEAD (R34 GTT RB25DET NEO)

th_turbo2.jpg

2nd Head

th_nonturbo2.jpg

why not machine the greddy manifold to accept the de gasket and just run with it?

would be cheaper than a new head...and would give increased port size.

The DET ports are a LOT bigger than the DE ports although it may not seem to be so from the picture. The overall diameter is larger, even though it looks like it bottle-necks on the DET. The CC's inside the head are far smaller than the DET which would result in different CR. Also, the neo DET cams push the valves too far out into the combustion chamber and i believe that the valve timing would overlap if the head was used with the Tomei cams for the DET neo. the machine shop would olny fully instal the exhaust cam, and left the intake cam cams evenly loose to allow the lobes to not depress the lifters which would result in the intake valves hitting the exhaust valves when rotating the cams to set the timing when the pistons are at TDC.

-John

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