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RB30/26

Spool race spec head ported and polished

hks 272 cams

tomie cam gears

sard fuel rail

sard 880cc twin spray injectors

Adjustable fuel reg

Standard 26 plenum with standard 6 throttle setup

Drain back from back of head to sump

6boost exhaust manifold

turbonetic gtk1000 turbo

tail 38mm gate

5inch dump into 4.5 straight though exhaust with hks dragger cannon

splitfire coils

Bottom End

rb30 block (Has been o'ringed runs standard rb30det head gasket)

rb30 standard crank ballanced With arp studs and acl race bearings

rb30 standard rods ballanced with arp studs and acl race bearings

rb30det cp pistons (dish tops) (85psi per cylinder)

JUN oil pump making 100psi when cold and around 65psi when warm and around 80-90psi under boost

ATI ballencer

Arp 12mm head stud

Power by

Microtech lt12s

bosch intank pump thats feeds a surge tank with 2 bosch 044 pumps feedind fuel rail

Eboost 2 for boost control

And only making 441hp on 18psi. Depressing after spending near 50g on motor only. Been to 4 different tuners and all have been from 420hp to 490hp.

When I bought the car it had the same rb30 bottem end as it does now but with a standard rb25 head ported and polished.(no cams or cam gears) cheap ebay exhaust manifold, garret rip off gt52 turbo with ebay waste gate and ebay fuel rail 500cc injectors, standard fuel system and a greaddy ripoff plenum. It was making 450hp at the wheels and went harder then it does now with all top name and quality parts. GO FIGGER. I CANT

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Interested to know how the motor bill came to $50,000 if its using essentially a stock RB30 bottom end (save for a set of pistons)... I mean even with the head & bolt ons included, you'd be lucky to pip 25k.

But of course, without decent information - no one is going to be able to help you.

Need to list anything and everything including...

- What has been tried so far

- Whats been tested

- What conclusions were reached

- Why only 18psi

- Tested boost drop across the cooler core

- Tested exhaust manifold pressure.

- What else was done to the head, surely that cannot be it

- What are the AFRs doing

- What is the injector duty

And thats just the start...

85psi? is that with a comp test?

even with the 272 cams it sounds kinda low, is the cam timing spot on? What comp ration is it meant to have?

With the oil pressure, does it make 90psi if you free rev it? or is it 65psi at say 5000 rpm off boost and 90psi on boost? If so than the rings aren't sealing.

Compression test will measure how the cylinders are sealing, low static compression will lower the result but it should still be higher then 85psi

Chrome moly rings? (cp's usually are)

4ra or 3ra bore finish? (aka was it honed to suit chrome moly rings?)

hmm... I'm making about the same power as you. Everyone tells me I 'should' be making more too.

I'm running -5's and 264 HKS Cams... is 450rwhp really that bad? How is the midrange power?

Is the dyno telling the real story?

Interested to know how the motor bill came to $50,000 if its using essentially a stock RB30 bottom end (save for a set of pistons)... I mean even with the head & bolt ons included, you'd be lucky to pip 25k.

But of course, without decent information - no one is going to be able to help you.

Need to list anything and everything including...

- What has been tried so far

- Whats been tested

- What conclusions were reached

- Why only 18psi

- Tested boost drop across the cooler core

- Tested exhaust manifold pressure.

- What else was done to the head, surely that cannot be it

- What are the AFRs doing

- What is the injector duty

And thats just the start...

This is excelent post. Now These are the things i wish these mechanics i been going to have done but they havent and seem to just brush it off to the to hard corner and just give me blank useless answers.

Well the head assy with cams and valves was around $6000 from spool 2yrs ago

plenum setup from spool was about $2000

6boost manifold was about $2000

turbonetics gtk1000 new was about $5500

the peice of shit turbonetics was gate that was sold to me to match the turbo was about $1200. Never sealed closed from new and was swaped with a tail 38mm

first build used a $400 tomie commetic head gasket witch didnt work cause of the oringed block.

sard injectors were around $1300

sard fuel rail was about $400

Cam gears were around $500

Fuel reg and 2x bosch 044 and surg tank and bosch intank pump plus fittings and braided hoses came to around $3000

eboost2 was around $1000

bosch coils replaced x4 was near $400

superspark coils $450 lasted 2wks

splitfire coils $750

factory coil harness $500

custom exhaust from 3.5 inch to 5inch from turbo into 4.5inch $1750 plus $450 for cannon

new microtech harness and repair and labour was $2500

All braided hoses and speedflow fittings in engine bay came around $6000.

new clutch $2000

Rebuild: all bottom end bearings replaced with acl race and all gaskets and oring and seals $3500

New ballencer $600

alloy radiator $450

This is just some of the costs i have came up against so far off the top of my head with out going though all reciepts.

All these costs listed are not including labour of what ever the shops were charging at the time. And not including

numerous dynos.

Things from the start to end that had to be changed from going from 25 to 26

1 Fuel system run out of puff on first tune attempt at 430hp.

2 Tune 2: waste gate was not sealing or holding shut. Turbonetics 50mm now running tail 38mm

3 Tune 3: exhaust was too restrictive and any boost over 16psi didnt make a difference

4 big oil breathing issue. Return fitted to the back of head to sump to fix prob

- Why only 18psi- either the tuner felt it was unsafe to go higher or there was no hp gain

- Tested boost drop across the cooler core- have always asked this to be done but never has been done

- Tested exhaust manifold pressure.- never been done

- What else was done to the head, surely that cannot be it- Not real sure. i was a spool head package. was told it had oversized valves ect. But to my suprise the valves have the nissan logo on them. Hks 272 cams 9.38 lift i think and ported

- What are the AFRs doing- soon as i find all dyno sheats ill scan and upload them

- What is the injector duty- not sure as i no longer have a hand set because a tunner kept it to borrow and some how lost it along with my laptop dongle

Thease are my reasons for not trusting most performace shops or tunners and am now asking on here for what every one else thinks.

I took it to a tunner not long ago to fix a missfire prob and they said the computer had 2 blown drivers in it. one was a coil driver

and the other was a injector driver and want $5500 to put a haltech in it. I refused and picked it up and took it home and found a

coil melted. Prob fixed.

hmm... I'm making about the same power as you. Everyone tells me I 'should' be making more too.

I'm running -5's and 264 HKS Cams... is 450rwhp really that bad? How is the midrange power?

Is the dyno telling the real story?

well some tunners that made 450 felt good and aggresive and others that made 450 just felt like a real smooth v8 grunt. But have massive lag but to be expected i guess because of the low comp.

over all 450hp is good but still a let down for how much spent considering the orriganal rb25 ebay package went harder

Jesus dude some of those prices... You took a fire hydrant up the ring big time :(

Anyway - Still haven't seen mention of what cooler you are actually running?

You mentioned stock RB26 plenum, but you mention an after market one?

What set-up is currently driving the splitfire coils?

I also doubt 18psi was not making any more power, I mean its a 1000hp turbo. A base point would be 25psi and well into the 400rwkw region.

If any more than 18psi was not showing anything, clear as day there is a problem. Could be something as simple as cam gears not set correctly initially, or something much bigger. Side point - cam gears incorrect could also explain the very low comp test combined with your head mods.

Wouldn't get too worried at this stage, frustrated fair enough, but its just a matter of working through things bit by bit.

Compression test will measure how the cylinders are sealing, low static compression will lower the result but it should still be higher then 85psi

Chrome moly rings? (cp's usually are)

4ra or 3ra bore finish? (aka was it honed to suit chrome moly rings?)

yes they are chrome ring. All i know was when i got new bearings put though it the said the ring and pistons were still great and hone marks were still fresh from when the owner befor me had the motor first built.

Jesus dude some of those prices... You took a fire hydrant up the ring big time :(

Anyway - Still haven't seen mention of what cooler you are actually running?

You mentioned stock RB26 plenum, but you mention an after market one?

What set-up is currently driving the splitfire coils?

I also doubt 18psi was not making any more power, I mean its a 1000hp turbo. A base point would be 25psi and well into the 400rwkw region.

If any more than 18psi was not showing anything, clear as day there is a problem. Could be something as simple as cam gears not set correctly initially, or something much bigger. Side point - cam gears incorrect could also explain the very low comp test combined with your head mods.

Wouldn't get too worried at this stage, frustrated fair enough, but its just a matter of working through things bit by bit.

Thanks for the hope. Cam gears have never been dialed in. have allways asked for that to be done but never happens they just tune it. its running stock plenum. the ebay one was on the 25/30 setup. The microtech has its own coil module in it. And as far as the cooler goes well its been there since i bought the car. no brand on it and could possiby be a ebay special to

problem i have is where i live there are 3 performance shops one is to expesive to go to and the other 2 have f***** me over and dont seem to know what there doing and the last tuner done a grreat job tunning it but only made 441hp but it keeps fowing up the front 4 plugs but the rear two are really white. i went back to him and showed him and his response was ( well i cant trim it any more because how lean the back 2 plugs are) and i said cant that be fixed by adjusting the 6 throttle bodies and his response was (not really sorry i cant help you. thats just how that plenum flows) Is this true

If you have been paying those prices, drive to brisbane and get a different tuner to take a look at it mate, its not far from toowoomba.

Talk to Mark at Godzilla motorsport in Wakerly, or the guys at EFI performance in Yatala :thumbsup:

Who's idea was it to put 30DET pistons in it?

Rips could sell you an RB30 with 400kw for half what you have spent.

Still you have some good gear just need to get it sorted

Cam timing could be way out. If tuners won't tune with the adjustable cam gears they are either too lazy or don't know enough.

Can't really help you from here but get some advice on a good workshop and take it there even its many miles away!!!

Good luck - it will come together if you get the right workshop/mechanic/tuner.

If you have been paying those prices, drive to brisbane and get a different tuner to take a look at it mate, its not far from toowoomba.

Talk to Mark at Godzilla motorsport in Wakerly, or the guys at EFI performance in Yatala :thumbsup:

Ok so i spoke to mark from godzilla motorsports today. He said that even if the cams were out it wouldnt affect that much power.

He also said the low compresion isn't a problem just means i have to double the boost to make the same power as other motors on 20psi

But he did say to f****** the microtech off cause they really dont work well at all and timing is always out or to much. (mine is set to 50 deg)

And he also said a smaller turbo to max out around 600hp and 1000cc injectors and then it will be mental. Said making 500hp on a smaller

turbo will fell like a 1000hp compared to 500hp with the turbo im using now.

Who's idea was it to put 30DET pistons in it?

Rips could sell you an RB30 with 400kw for half what you have spent.

Still you have some good gear just need to get it sorted

Cam timing could be way out. If tuners won't tune with the adjustable cam gears they are either too lazy or don't know enough.

Can't really help you from here but get some advice on a good workshop and take it there even its many miles away!!!

Good luck - it will come together if you get the right workshop/mechanic/tuner.

Marty White from white brothers racing built the motor for the owner befor me. Reason For running rb30det piston- (DRUGS I GUESS)

you said

rb30det cp pistons (dish tops) (85psi per cylinder)

your cylinders are loosing compression due do something NOT sealing and he recomends to up the boost to compensate? bad advice there

compression test is the pressure the piston is making whilst on the upward stroke

compression ratio is a volume / how many times the volume of the piston at Bottom Dead Centre can be squeezed into the combustion chamber when the piston is at Top Dead Centre

here is what i suggest, find out why your only getting 85psi and not something around 130-150psi during a compression test, correct that issue and you may have solved one problem

Ok so i spoke to mark from godzilla motorsports today. He said that even if the cams were out it wouldnt affect that much power.

He also said the low compresion isn't a problem just means i have to double the boost to make the same power as other motors on 20psi

But he did say to f****** the microtech off cause they really dont work well at all and timing is always out or to much. (mine is set to 50 deg)

And he also said a smaller turbo to max out around 600hp and 1000cc injectors and then it will be mental. Said making 500hp on a smaller

turbo will fell like a 1000hp compared to 500hp with the turbo im using now.

Thats obvious that using a huge turbo like you have now to only make ~450rwhp is not a good thing. You would be much better off with a smaller turbo that would make the same power with a lot better response.

You have a choice either you change to a smaller turbo and make the same power with more response or you keep troubleshooting and chasing the big hp that your turbo is capable of.

Big power is not just a matter of bolting lots of parts together and presto, it takes lots of troubleshooting and trying different parts to see what works on your car. You really need to find a tuner who you can talk to and say look I want your advice, I want you to troubleshoot to see what is holding it back and you are happy to pay. I mean after all the $$ you have spent on the parts you may as well put some decent money into the tuning and troubleshooting. If the 3 local tuners are not coming to the party then it may be worth taking the trip to Brisbane as mentioned above.

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