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Hi guys,

I am planning a 2530 into my S2 RS stagea (rwd, neo)

Now heres my dilemma. It is my daily, so need to be able to do an engine swap in a weekend, so cant pull down my engine to do it.

I have bought an RB30 and a non neo RB25de to use the head.

The plan is to put the neo inlet manifold onto the head, due to injectors, sensors etc.
The thing is I know the neo exhaust valves are bigger, so how much would using a non neo head hurt the power?

I am not after huge power, currently making 285 with a GT3071 and will be using the same turbo. Looking at improving drive-ability and torque.

I have searched like mad but cant find an answer.
So has anyone put a non neo rb2530 into a car that had a neo, and what was the outcome?

Thanks

Ben

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Thanks. it is an r33 head.

The issue with using my head is the time it is going to take to have to weld up oil feed and run external line.

I have a Nistune and am running ls2 coils so ignition wise no problem.

I am leaning towards using my head, will just need to wait a while as a result.

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Neo head is far better...you'd be silly to go backwards..

what about 25/30 height difference, i thought(maybe wrongly,i havn't done it) that you have problems with manifolds

due to extra height? can you use standard inlet and ex manifold?

where did you dyno your car?

cheers

darren

Edited by jet_r31
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Thanks guys, thats what I thought!

And no joke about no matter what it wont be ready in a weekend, I was deluding myself for a bit there.

Just wondering if anyone knew from experience, but I suppose people dont normally try a backwards step to see how bad it is!

Edited by superben
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Neo head is far better...you'd be silly to go backwards..

what about 25/30 height difference, i thought(maybe wrongly,i havn't done it) that you have problems with manifolds

due to extra height? can you use standard inlet and ex manifold?

where did you dyno your car?

cheers

darren

Hi,

I have roughly checked the height issue, and it seems all good. Was planning on triple checking soon, there is always the option of dropping the engine a little to gain more clearance if needed.

Car was Dyno'd at Garage 7, plus I bought the nistune individual licence and already had a wideband data logger.,

Tuning seems pretty good, at cruise and WOT, but there are some heaps rich spots around 3/4 throttle to tweak. Its the VE map thats doing it.

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If someone can show me a NEO head out perform a non NEO head for power and response on the same motor ill eat my shirt.

The only advantage I see with a NEO head is the ability to use bigger cams while retaining VCT, all other differences would be hard pressed to see a change on a dyno.

Use what you have and save your $$$.

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What are you showing me exactly?

Spend a few grand on any head and it will out flow a stocker.

What I am saying is by bolting on a NEO head over a non Neo head you are not going to see something magical happen power and response wise.

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that's just like saying leave the single cam head on, because with double cam u won't c improvements in power and response

Everyone knows if u can retain VCT, it significantly improves bottom end response and torque

but since he has the non neo head already then it will still get the job done

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that's just like saying leave the single cam head on, because with double cam u won't c improvements in power and response

Everyone knows if u can retain VCT, it significantly improves bottom end response and torque

but since he has the non neo head already then it will still get the job done

You are comparing two TOTALLY different heads there mate.

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If someone can show me a NEO head out perform a non NEO head for power and response on the same motor ill eat my shirt.

The only advantage I see with a NEO head is the ability to use bigger cams while retaining VCT, all other differences would be hard pressed to see a change on a dyno.

Use what you have and save your $$$.

youd be safe as you know its not going to happen..lol, i bet on a 150mph car there would be,maybe not the small shit though

cheers

darren

Edited by jet_r31
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