Neo Head Or Not?

[mungy]

have to agree, while the neo head is better, far superior is a bit steep, both motors in good condition with same mods produce a very similar result

any proof otherwise?

did hear of a neo flicking a shim out recently but didn't hear back why

Ok let's look at FACTS, direct bolt on of either head onto the same 30 block the neo head WILL outflow the R33 head, not by much but it WILL..

Secondly the neo head has a higher power potential, what I mean is if everything is left standard on both heads the neo will be able to handle more boost and higher power levels.

Now.. WMDC35 yes the manifold from a neo will bolt onto a 33 head but the ports don't match, neo has larger ports. The neo head is superior in any way you look at it.

[WMDC35]

exactly not by much, not far superior, so what are you on about?

my spare motor is a neo, i'll put it in this weekend if you've got some proof it will make a fair difference over the non neo?, as nytsky says show some proof? in some ways i can't wait for my motor to blow so i can back to back the s1 & neo with the same setup, 350+kw, you must've already done this so show us?

as i said we know it's better but results are not far superior was all i was saying

you're still going on about facts & credentials which nobody denied

where's your proof now mungy?

[mungy]

exactly not by much, not far superior, so what are you on about?

my spare motor is a neo, i'll put it in this weekend if you've got some proof it will make a fair difference over the non neo?, as nytsky says show some proof? in some ways i can't wait for my motor to blow so i can back to back the s1 & neo with the same setup, 350+kw, you must've already done this so show us?

as i said we know it's better but results are not far superior was all i was saying

you're still going on about facts & credentials which nobody denied

where's your proof now mungy?

thats like saying solid lifters and better springs with bigger ports in the head is not enough proof that its better....wtf?

If we all go by your argument there is no point in buying titanium springs and the rest because "its not much better in a standard motor". Your right ITS NOT, but it gives you the ABILITY to put higher power through the head........come on guys wake up, if you put both heads next to each other on a 30 bottom end with no mods the neo will slightly out perform the r33 head, but when you go to MAXIMUM power you can put through the head the neo will handle a huge amount more thatn the 33 head before it will need modification, thats just logic.

you cant say "Usain Bolt MIGHT be faster than me in a foot race, but Ive never raced him so theres no proof"

[NYTSKY]

How much power are you talking? 1200hp at 11,000rpm

I and all of my mates with BIG powered RB25 combos revving over 8000rpm are using the non NEO head. If there was a significant difference in power and response we would have chosen the NEO....but there isn't.

[WMDC35]

thats like saying solid lifters and better springs with bigger ports in the head is not enough proof that its better....wtf?

If we all go by your argument there is no point in buying titanium springs and the rest because "its not much better in a standard motor". Your right ITS NOT, but it gives you the ABILITY to put higher power through the head........come on guys wake up, if you put both heads next to each other on a 30 bottom end with no mods the neo will slightly out perform the r33 head, but when you go to MAXIMUM power you can put through the head the neo will handle a huge amount more thatn the 33 head before it will need modification, thats just logic.

you cant say "Usain Bolt MIGHT be faster than me in a foot race, but Ive never raced him so theres no proof"

all i said was that far superior was a bit over the top, i wasn't arguing anything that was you, now you're just waffling, talking about usain bolt? is your caps lock broken?

the op is using a 3071, so will be a very similar result as i said, you must have something to show that you had a far superior result from the neo head and no other factor?

with max power through the stock head is debatable as the neo runs shim over bucket and know one that has flicked one out recently

a good result can be done with either head

everyone knows the neo is the one, just far superior is a bit of an over statement

if you're talking big numbers as nytsky suggests the highest one i know personally runs a 26 head at over 1600hp, is that where you're at? the thread was about 300ish kw's

it's quite hard to find a fair comparo, my s1 has only done about 90,000ks is stock and over 350kw, the neo i have is 105,000ks so will back to back them with same setup when the time comes and will post it, a known good s1 vs a known good neo, people say the neo gained them this & that but their old motor was too tired to compare fairly

simon-s14, your 30 used to have a neo head now a 26? seen any shims flick out of any neos?

[Simon-S14]

ive never span any shims on a neo.. but have seen some that have, probably due to aftermarket cams that wernt 100% true.

i never ran the neo on my rb30

[WMDC35]

yeah it must be something to do with the cam & spring setup

[jet_r31]

im more interested to see what a 3071 and a rb30 bottom end does in regard to backpressure.....

cheers

darren

[mungy]

simmo it just so happens I have a spare neo top end now, I still have the head from the R33 drift car and 2 good RB30's sitting in the yard waiting to be thrashed. I say we slap em together and get decs to tune em and finally see which is better...... anyone for a bet?

[mungy]

simon already had that setup, mayb ask him

im more interested to see what a 3071 and a rb30 bottom end does in regard to backpressure.....

cheers

darren

[Simon-S14]

mine was 3076 with .63 rear. was spastic!

[Frosty]

this thread brings the LOLZ

only benefit of a NEO head is solid compared to hydraulic and slightly bigger ports! any benefit here! NADA!

On a side note i rev my hydraulic head to 9k

[Simon-S14]

neo head has smaller CC also dont forget that

[Ben C34]

Yep. So in the case of throwing a head straight onto an rb30 that is a positive.

nissan didn't redesign the head to make it worse. From a manufacture point of view solid lifters would be more difficult to manufacture, having to set/check clearance.

So they designed it for no reason? ?

Anyway i have bought a good running rb30 and will be using that. Will use my neo head. Will be doing it on a week or two. Will post updates.

[discopotato03]

Everyone can make assumptions these are mine .

R34s were getting into the ULEV era of lean burn mixtures so assuming fuel octane didn't change markedly something had to be done about combustion heat and detonation . I'm going with improved head jacket cooling to minimise chamber and valve head temps . Maybe not a huge performance gain but retarded ignition timing from detected detonation does'nt help with emissions or consumption .

Smaller volume chambers . Less surface area to absorb heat and a lower piston crown to maintain the same 9:1 static CR .

Non hydraulic cam followers . This allows more agressive lift rates so better cylinder filling without longer valve open duration . I wouldn't think hydraulic followers/buckets would like cams like these and possibly hard to keep things quiet .

Shim or disc over bucket valve clearance adjustment is always MUCH easier to service than shim under bucket systems like say RB26s and FJ20s use . Over bucket means you can push the bucket down and change shims without having to remove the cams and buckets like you do with a 26 or FJ .

Honestly under bucket is how a competition engine should be because the shim/cap is small and light and can't go anywhere at high revs . The over bucket shim/disc is the way to have a road engine so it can be easily serviced and doesn't need to see 7500+ revs too often .

If starting from scratch I'd always use a Neo 25T head given a choice because with its native inlet manifolds solves the niggling issues 33 25T top ends have - like the hydraulic buckets - and the limiting side feed injectors . Matter of opinion but I reckon std GTt cams are better than std R33 25T ones because they open the valves faster . In a nut shell if you can get around the CR issues of that smaller chamber a turbo Neo head is as good as an RB25 head gets to be IMO .

My 2c spent , cheers A .

A .

[Ben C34]

Thanks Disco, well written. Very good point about the cam ramp rates which are overlooked when comparing duration.

The compression isnt drastically changed running the neo head vs rb30, it is bumped up a bit which is preferable in my instance.

From research it seems the RB30 heads are 50 cc and neo heads are 50-53. Worst case 50cc would bump comp on rb30e bottom end to 9.7:1

I will be selecting a gasket thickness to give preferably 9.5:1 comp, after having head welded and skimmed, then measuring chamber volume. I am not after max power, Just a really nice tourqey combo for daily use.

[jet_r31]

Should be epic in the response levels!, i don't remember seeing one fitted with all standard intake and exhaust yet

so really looking forward to seeing if any problems are encountered, hopefully its smooth sailing(although it is a f**kin car..lol)

cheers

darren

[discopotato03]

For a cheap E85 engine 9.5-9.7 static CR should work out pretty good for a roadie , always provided the turbo wasn't too small or boost too high for the NA pistons .

A .

[Ben C34]

Update time. Had a two week windrow whee I could borrow a car, decided on using neo head and a good running bottom End. slapped together and tuned 305rwkw at just over 5000 rpm. heaps of torque and awesome on the street. Car now really stalls to 2500 so that will help alot. Currently at AIR waiting, about to run it down the strip. So to recap only mod is rb30 bottom end compared to last time running 12.7 at 114.4 with a 2.1 60ft. Will update later.

[corey.hunter]

Does anyone know whether the neo head coilpack harness will work with the rb25 s2 coilpacks?

Thanks