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Hi

Guys some may know that I am currently building an engine that will be going into my R33 GTS the specs are:

RB30 Bottom End (Rated at 1200HP)

it is getting the whole treatment

Forged Pistons

Custom Rods

Rods Bolts

Clevite Bearings

Main and Head studs

balanced to 8000rpm

Oil restirctors

What i am confused about deciding on is two things CR (compession ratio) and head work ie porting, cams etc etc.

The turbo i will be using is a HKS T51R SPL (non ball bearing) my power targets are 800HP at the engine on Optimax and if possible 1000HP at the engine on race fuel. Please bare in mind the engine will be in a street car using a custom built auto i aim to drive it on the street with a detune state say 600-650HP. THe reason of the power targets are that when it does hit the track I want to know the engine can take it and run the numbers. So i need to know if

1) Will a CR of 8.5:1 with a Apexi Power FC PRO or Autronic SMC and the T51R allow 800 on pump fuel and 1000 on race ful?

2) What head works ie cams, springs, retainer and port work will be required to flow this HP also I do want it to be reasonably tractbale hence the relatively high CR

3) Which engine managment, ignitions system would people recommned, the fuel system will consist of a lift pump (33 GTR) and two main feed pumps (Bosch 044) and 1000ccc Rochestor Injectors.

Any input would be greatly appreciated I know this is a big ask but I want this to remain streetable when detuned to 600-650 for the street when the 800-1000 comes in for the quater I dont mind as the transmission is a drag box designed for limited rpm power band.

Regards,

Jordan

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Well i'll try and keep it straight regaridng track work i will try it and see how it goes but i suspect by the time im on full boost 5,000rpm it will be time to slow down again. The main aim is a TUFF street car to show the big V8 boys a 6 turbo Nissan can do it aswell but i want it to have the potential to run a single didigt number down the quarter

Jordan

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Dude, I doubt this will be very streetable. If you do want something for the street, I would suggest perhaps 2 fuel rails, otherwise you are going to have a prick of a time trying to get it to idle nicely with 1000cc injectors - my mech was saying 850's were a bit big. I am thinking autronic or motec for that sort of power - no laptop for power fc plus you can stage the injectors.

Sorry I wouldnt have a clue what would be needed to be done to a head for that sort of power, but I would think you need to do everything:D

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Guest Shunted

"Balanced for 8,000 rpm"

I would be thinking you need alot more revs under your belt for 1000+ hp - for 10k rpm you would need a custom crank (or you can pray to Allah everytime you launch the sucker that the standard crank will hold). Does the $6k for the bottom end include an aftermarket crank?

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The engine being a 3 litre doesnt need a 10.000rpm rev ceiling its not an Rb26 since power=rpmxttorque I will need 660ft/lbs to make 1000 please keep in mind im asking for suggestions on what setup not wether you think i can pull ot off the crank has made 1020 by NIZPRO and that only revved to 7,500rpm check Zoom for proof

Jordan

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GR8NES,

Sounds like a fun weekend car your building. Depending on how often you run the thing down the 1/4 at 1000hp it will maybe need a basic rebuild every year or two, less if you give it a dozen 1000hp passes or more a year. Remember the diff , it might be a little cheaper to get a custom 9inch built up.

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Jorden,

Check your email dude, :P

Also in regards to the Cams, i am getting mine completley remade from wayde cams in melb. I am not going as hard as you but if your thinking about buying HKS/JUN/NIZMO/APEXi cams goto a cam place is syd, take the specs of the cam you want (EG. HKS 256D 12MM lift) and they will make you a set of cams EXACTLY the same (probly stronger, depending how much you wanna spend) for half the cost.

Also for the HP your chasing a half decent set of Valves "Pro-valves" would do the trick, about $1400 for 24 valves (Not too sure if it includes guides/seats etc.), and a nice open port & polish. ($800- $2000) depending on the job. Youl also need a nice big volume plenum.

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HKS cams only cost 1k for the set ex japan, it may be a little dearer than rebuilding the stock ones, but they are made from one piece of steel. Adding steel and regrinding is a bit bodgey for high rpm applications IMHO - and it doesnt save you money. You are spending enough that it would warrant getting it right the first time.

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I never was going to have the standard items modified I wanted to look into some custom items made in Australia from scratch if they are available.

What I am really interested since the cams im pretty much decided on as 272 11mm lift items is the compression ratio will 8.5:1 be too high for 800 on 98 RON fuel or will 8.0 be better??

Jordan

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