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Ok. To start with this engine is in a lc gtr torana. So it's fairly tight in the engine bay.  Pic of engine bay is old setup 25neo

I'm about to get my head back for my 30 25 neo and need some help pointing me in the right direction on a couple of questions at the end of the post.

But first I will give you a full spec list of the setup. 

Specs are

30 block

Crank welded and modified for 25 oil pump

All resized and nitrared so as new.

Spool h beam rods arp bolts

ARP main and head studs. 

87mm Forged arias pistons -10.4cc

Zero deck height

Jim berry modified clutch 4200 pound clamp

N1 oil pump

N1 water pump. 

2 x 1mm oil restrictors

1.3mm mls head gasket

Head has exturnal vct mod -3 lines. Ported inlet and exhaust performance valve springs and type b pon cams. Head cc is decked to 49cc

Giving me a 8.5 to 1 comp

Freddie intake manifold match ported 

1000cc bosch injectors e85 compatible

Walbro 460 intank pump. 

Custom made steam pipe exhaust manifold hi mount

Gtx3582r with 45mm exturnal gate off exhaust housing. 

Running 22 to 24psi for pump 98

3 inch from turbo back exhaust

100 cel cat straight through muffler. 

The only thing that will be holding it back is I only have a r34gtt Nistune ecu with hpx1 afm at the moment. 

I have read several post on here about cam timing and still haven't heard of anyone getting the best setup or no one is willing to let on.

I'm also not sure if I should dump my spitfire coil packs in favor of ls9 truck ones.

Also not sure if I should dump the factory cas for a rossi cas trigger. 

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Edited by lcxu105
Missed some info
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 No-one got back to me with the "secrets" of cam timing but my local shop suggested better valve springs but you have addressed that... and I fitted an adjustable cam gear to the exhaust to be tuned on the dyno. What sized rear end do you have on your GT3582R?

The only downside I see to your build is the relatively low CR at 8.5:1 but you may be able to overcome that with heaps of boost. Will not be so crisp off boost.

No need to change the splitfires ( I used brand new OEM gapped to 0.8mm) - if you find they are not keeping up you can change them later. The Nistune may not hold you back so long as you have an AFM that can cope. When and if you change to a more sophisticated ECU you will probably need to replace your CAS with some other kind of trigger.

Depending on the spec of your turbo I am picking you should make at least 400KW

Its a .82 rear on the gtx3582r.  If I can feed more boost into it I will. 

Being that the engine is in a lc gtr torana that is only 1000 kgs I'm not to worried about it off boost. 

Due to the fact that the 30 bottom end will produce more torque than the 25 neo it should be fine. 

5 hours ago, lcxu105 said:

Thanks for that. 

Will get some picks when I get the head back hopefully by the end of the week.

Always wanted an LJ. Strangely I am more a 6 cylinder guy than V8s.  I was really trying to get my brother to buy one but I ended up getting him an SS Chevelle out of the US. Mega cruiser but LJ would have been a more entertaining drive

Nice colour! I like the slr style front spoiler too! I had a LJ close to that colour a few years ago, I miss that car 579f36af5cf99_ImageUploadedBySAUCommunit
Id like to see how the 25/30 goes in the torana, I've only been in them with 186's and 202.

Like a cut snake on water. 

With the 25 neo same top end less porting and 18psi boost 422rwhp cold do 0-100 in less than 4.2 seconds.  And standing 1/4 in 10.9.

Had it up over 235ks on Lakeside raceway. 

I'm looking to make an extra 100hp at the wheels and a shit load more torque. 

I hope that the 20g is worth it. 

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