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About September last year Cat's race engine suffered a failure after running 3 laps free boosting (35+ psi). Initial thoughts on the day were a damaged valve but (slight miss and knock) a few more starts at the track to try pinpoint the noise the missing stopped and only a slight knocking remained so I dismissed valve train issues.... trying to pinpoint the knock was difficult at a noisy racetrack but it was definitely not the usual bottom end knock it was quieter. Knowing the engine needed a strip down I pushed it aside and left it parked gathering dust. With a new business and all the extra cash all being re-invested on new workshop equipment and setting up the showroom the car sat gathering dust for 6 odd months... very depressing.

After strip down it soon became obvious as to the source of the noise and thankfully it was not the bottom end, my trust pistons and Tomei rods were safe as was the "use what I had" r32 crank (complimentary 3 thou bend :D ) with a pro-engines collar. The crank will be retired (new cranks from NISSAN are ridiculously cheap now) and replaced with a new R34 GTR item.

The cause of the noise was a broken intake guide, the guide had broken and attached itself to the top of one of the pistons and was digging a nice hole in the quench area (hence the light knock). The head was recoed 12months back but due to the rushed build of this engine (3days from machining to competing) the inlet side was left alone. The exhaust was treated to new guides and valves but the inlet side all measured up ok. Usually finding the cause of guide failure is easy but in this case there were no tell tale signs. Common causes are impact, poor lubrication, incorrect valve stem height etc. In this case only a very small portion of guide was missing, usually the whole tip comes off during failure not just a small fragment... even the valve stems were clean and undamaged, the remaining guides were all perfectley serviceable..... There is a first for everything.

The old build recipe;

R33 block

Trust pistons

Tomei H-beam rods

King bearings

Trust oil pump

Trust head gasket

Status Oil restrictor kit

Tomei sump baffle

R32 crank with Pro-engines collar (3 thou bend :) )

Std R33 head with new ex valves and guides

Relieved cam valley for big lift cams

Trust 264 9.7mm lift cams (babies for now)

Std Plenum

The new recipe is basically the same but with a big $$$ head setup;

R34 crank

MLS head gasket

King bearings

Ferrea 1.5mm oversize valves in and ex.

Ferrea Titanium retainers and collets

Ferrea Double valve springs

Ferrea Spring locators

New Genuine buckets and shims

New guides

Larger rear housing for the K5-660R, after we get a baseline comparison with the old engine.

Nismo intake plenum as we found the STD one was compromised for flow distribution.

Link G4 (Vipec) ecu but only after car is fully sorted on the PFC D-Jetro as there is no real reason to swap other than using it to demo features to customers, I feel the Link fills or offers an alternative for those who can’t source the now more expensive PFC as easy. The PFC will retire to my C34 RB26 Laurel.

With the fresh build we will to try out a few new things which will end up in customer engines provided they prove reliable.

Pics up soon as I will do all the assy 2moro as I won’t get hassled or interrupted.

The new store project car is a C34 laurel which started out with a T78 equipped rb26 but currently is engine less and awaiting its new power plant.

Engine recipe is more budget based and will be used to develop a budget setup, many of our SR20, RB25 and 26's seem to be for pretty serious customers and have all been up there for $$$ build wise due to the components used and the proven nature of the builds (zero failures to date). So i decided to put together something fairly simple.

This budget engine will be abused to within an inch of its life, yet cheap to build including the supporting turbo etc....

R32 block

Status oil restrictor kit

Resized STD rods

Pistons (under testing atm)

R32 crank pro engines collar

N1 oil pump

King bearings

STD rb26 head

Kelford springs

T4 external gate manifold

Tial gate

HX-35 turbo

Again pics up soon of engine and car.

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Nismo intake plenum as we found the STD one was compromised for flow distribution.

How did you measure this? I agree but would like to know if the nismo item makes any difference.

edit to ask, will the vipec/link allow individual cylinder corrections based on load?

Edited by DCIEVE
will the vipec/link allow individual cylinder corrections based on load?

Sure can mate. You can trim each cylinder individually using either a single amount OR using a full 3d map, and you can set the X & Y axis to be whatever you want it to be.....Go LINK ! :/

Gary

is cat still going to use the good engine?

yeah she will get the good one, we will probably start to do alot more grip setup as we are planning to hold our own track days (grip/drift) for our customers next few months. With the folding of DA we are finding more and more people wanting mixed days.

How did you measure this? I agree but would like to know if the nismo item makes any difference.

edit to ask, will the vipec/link allow individual cylinder corrections based on load?

EGT's and good old plug reading.

I've taken bit of a plunge here with the nismo item based on some conversations with some of my jap contacts, i would love to do some back to back tests with the hypertune item and the greddy version against the Nismo.....

Edited by URAS

What cams with the big $$$ head, or is that a secret?

Also, sticking with the Blitz K5-660R, staying with a good thing. Do Blitz have a split pulse option on their housings?

Sounds exciting, 1.5mm oversize valves!!!

What cams with the big $$$ head, or is that a secret?

Also, sticking with the Blitz K5-660R, staying with a good thing. Do Blitz have a split pulse option on their housings?

Sounds exciting, 1.5mm oversize valves!!!

mis-type on my behalf, 1mm overs only..... i was thinking .5mm over on the pistons but typing in the valve specs.... by the time i went bak in i could not edit it.

the Blitz stuff is not available in split pulse.

Cams are only babies atm 264 with 9.7mm lift, gonna do some testing on the camtech stuff.

few pics:

I was very impressed with ATI's 7" balancer, cant wait to get it all fitted up.

rest of the pics are pretty general, pic of the crank and its grub screws (NEVER leave the factory alloy plugs in), Arp main and head bolts, H-beam rods etc

CBF'd assy it yesterday as ive got so many motors on the go in the shop....i went to the melbourne comedy festival and saw Arj Barker and Tim Minchin instead ;)

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Edited by URAS

Decided to run the TRUST plenum as i can have it here 2moro, so if anyone wants a cheap (brand new) HKS 11mm fuel rail let me know as the TRUST plenum i bought comes with a rail kit.

post-34927-1241001276_thumb.jpg

Edited by URAS
Who sells the ATI's in OZ Trent ? They do a rb25 one too ? What price ?

Gary

i needed mine asap so i ordered it via may machinist, I reckon mine came from precision parts here in vic i paid about $906

CJ have them a bit cheaper here http://stores.shop.ebay.com.au/cj-motor__W...Q_fsubZ20921914

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