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All, 

 

you may have seen my other post where I mentioned of large smoke. After diagnostic, it worked out one of the cylinder had 75% leak .

Decision is now to do a full forge rebuild to support 700+ bhp at fly.

what he found out was the cylinder with issue had its injector flowing fair bit less fuel and he thinks that is what has done the damage by running it very lean.

 

I will list the specs and mechanic wants 3k for rebuild as labour which is almost 5.5 k in Au dollar. he is one of the best here and all he touches is r34 and skyline

there is then 2.5k which is another 4.5 k Au for parts .

I then have to spent another 5k pound which is 8-9 k Au on turbo , manifold, intercooler etc to get 720 so in total around 11k pound so almost 20k Au . would you pay that ?

 

would you pay that ?

 

spoke to few tuners and some weren't confident on providing warranty on the build due to power but he is . 

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No I would not. How rich are you? With 700+hp you will need a lot more spending - new clutch, gearbox, brakes suspension tyres.

Pull the engine apart and see what it needs. You may just need a set of pistons and bearings. Neo has GTR rods and oil pump so if its in good nick will support 300 to 350RWKW without forged parts.

In NZ I would be considering an RB30 bottom end for the Neo head but may not be so easy for you.

I am sure you could buy quite a nice car for 20,000 pounds but if you want to spend it on your old Skyline and that makes you happy go right ahead - but take the time to pull the engine apart and see exactly what your options are.

43 minutes ago, KiwiRS4T said:

No I would not. How rich are you? With 700+hp you will need a lot more spending - new clutch, gearbox, brakes suspension tyres.

Pull the engine apart and see what it needs. You may just need a set of pistons and bearings. Neo has GTR rods and oil pump so if its in good nick will support 300 to 350RWKW without forged parts.

In NZ I would be considering an RB30 bottom end for the Neo head but may not be so easy for you.

I am sure you could buy quite a nice car for 20,000 pounds but if you want to spend it on your old Skyline and that makes you happy go right ahead - but take the time to pull the engine apart and see exactly what your options are.

I agree but then with 11k uk pound, I can’t get any car with 700+ bhp

 

clutch is rated at 850hp, suspension all good, brake is evo

 

only thing that i am worried about is diff and gearbox. What gearbox do you need for 700 hp?

 

part cost is majority of the expense to be fair.

 

what do you consider fair in au to rebuild an engine?

well any tuner or mechanic will charge me above 1.5k which is roughly 2.5k au to strip and change a piston so if i am paying that i might as well do headworks and forge it !

everything on the car is there to support 600-700 bhp apart from swirl spot for fuel and possibly using walbro 450 vs 044 bosch and swirl pot.  

 

what i need is serious feedback from some one to say if the gearbox hold up to 700-800 bhp? I won't be spending 5k on sequential gearbox  Samsonas

26 minutes ago, Ben C34 said:

The gearbox will break at some point.

Your choice is to then keep putting in stock boxes or spending the cash to get something that won't break.

that is why I am asking what people do put in that lasts .

 

Are we talking 200 miles or more 4000-5000 miles?

 

My third gear is dodgy and think gearbox will pop at somepoint . 

 

re spending money , look to all critics here, I am not rich nor almost 20k Au is cheap.

However I never intend to sell it as it is my dream car so I might as well boost it up to 700+ bhp and enjoy it. It should be driveble with good tyres and little skill.

 

I have managed all the way to 600 bhp with full traction off and this is a new challange as never had a 700+ bhp car

700 bhp = 550 - 600 rwhp dependant on driveline..........on e85 it might last a while as stock on pulp not long

 

gearbox big jump from something that stock to something that will handle the power like PPG dogbox  $11,500 AUD new

 

might get start up warranty but thats bout it ...wouldnt expect anymore on a build

 

1 hour ago, WR33KD said:

Has any one done what he is wanting to do?

Yes plenty. It is certainly do-able - refer the turbo upgrade threads.

But it is expensive and can end in tears (engine failure).

The question is how much do you want /need it?  And that's entirely up to the OP.

41 minutes ago, drifter17a said:

Is that engine failure with full forge?

Yes it can happen. Engine life depends on quality of build, quality of tune and how it is used or abused. Then there is always an element of luck. Have a read of the "report that engine failure " thread.

This is not to suggest that it is likely but from my limited experience of track days RBs seem to be the most common cars being pushed on to trailers with dead engines. (To be honest that's two cars - one GTR and one Cefiro).

Not trying to scare you - there is a lot you can do to prevent failure  but be at least mentally prepared for the worst.

A 700hp car is only making like 40hp when driving around in traffic. As a result it can last years.

If you want to be serious about how long a 700hp engine lasts while making 700hp the reality is this is a matter of hours.

Same story with the gearbox. Think about it, do you think Ferrari and Lambo and GM are making 5+ Liter V8/V10/V12 for no real reason, why not make a 2.5 with a massive turbo on it that'll last forever if 700hp is going to last a long time under heavy use.

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13 hours ago, drifter17a said:

Is that engine failure with full forge?

"Full forge" engines are nothing to write home about. You get more strength to take more power yes, but it's not a magic bullet. Any detonation event when you push that hard (250+ hp/L) is going to be catastrophic. Keep in mind that forged engines need higher clearances as well, that means it's more likely that you'll get piston slap on cold start and increased wear. A stock RB25 can go hundreds of thousands of km before needing a rebuild if it isn't abused.

If you don't really know what you're doing and you want a warranty, stay conservative.

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16 hours ago, WR33KD said:

Has any one done what he is wanting to do?

yes I have 

Ive done 500 - 550 hp on stock engines for 8 years (on the track) with standard gearboxs and also now 635h (so 700+bhp as op wants) , also have gone from std box to ppg dog box

you got more chance of it lasting as a road driven car than track for sure but strain is strain

Also there is no mention of fuel used - anything using normal PULP fuel going anywhere near those numbers forged or not is asking for trouble

what the OP wants is what he wants... but Id say what most of us would do would be a responsive as possible 500rwhp stocker on e85 with std box and be nice to it most of the time with occasional thrashing

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