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Sounds like you may need to do a dummy build to check valve piston clearance.

The Tomei pistons will be valve relieved to suit and will be checked at HKS just before being sent over.

He might have a little bit of knowledge but if those inlet ports are polished (which they kind of look like they are) there are deficiencies in how that inlet port will perform... that is the bottom line, it is FACT! Whether he has built 10 engines or 100 means nothing. Plus the fact that this head also has +1.5mm inlet valves is a whole other issue...

I don't think it is right to continue this on Piggaz's thread, apologies mate. Marcus send me a PM or email if you like.

no way post it in here, i think everyone wants to here what you have to say, i sure do, gunna be good to watch you eat your words at the end of it all once its bolted togethor and put on the rollers......

He might have a little bit of knowledge but if those inlet ports are polished (which they kind of look like they are) there are deficiencies in how that inlet port will perform... that is the bottom line, it is FACT! Whether he has built 10 engines or 100 means nothing. Plus the fact that this head also has +1.5mm inlet valves is a whole other issue...

I don't think it is right to continue this on Piggaz's thread, apologies mate. Marcus send me a PM or email if you like.

Pm both of us !!

Polished ports - not ideal, but port shape/size is what really matters

guys back in the 60's experimented with chroming the inlet ports to a true mirror finish, didnt gain anything...but didnt really lose anything either

what I want to know is why is there a blob of what looks like weld attached to the valve guide in the inlet ports, and still using factory cast iron guides? or will they be removed after the porting is finished?

no way post it in here, i think everyone wants to here what you have to say, i sure do, gunna be good to watch you eat your words at the end of it all once its bolted togethor and put on the rollers......

No need to get defensive, anyone can PM me if they like.

I did not say it won't make power, etc... but the port looks polished from the photos. If it is, then in my opinion, it won't flow as well as it could at certain engine speeds. The +1.5mm intake valves might be an issue too, going too big a valve can hurt flow around the valve head at lift "valve shrouding"... the head of the valve can get too close to the cylinder wall.

Polished ports - not ideal, but port shape/size is what really matters

guys back in the 60's experimented with chroming the inlet ports to a true mirror finish, didnt gain anything...but didnt really lose anything either

what I want to know is why is there a blob of what looks like weld attached to the valve guide in the inlet ports, and still using factory cast iron guides? or will they be removed after the porting is finished?

Valve guides are JUN bronze items.

Mike it might just be the way the photo was taken.

I'm picking up the head ,pistons and a few other parts next Friday and will send Paul some pics.

Keep in mind this head was all machined by Naprec to their full racing specs and fitted with their bronze valve guides 1.5 over size forged valves and will spin 9,000rpm all day long.

All the port/polish and other work has been done at HKS by one of their top race engine builders.

This spec head is tried and tested in Japan and no problem with flow.

Sorry if came off as defensive but long flight yesterday and topped off with a nomihodai one could say things are a bit foggy this morning.

Anyway lets keep this on track as its all about Pauls new "Pig Monster"

When you look at the list of high powered engines this guy has developed in the last 15 years in Japan from the Drag33 to time attack engines down to current GTR35, you know he has got a little bit of knowledge of what he's doing, plus he's got the runs on the board having built literally 100's of race engines and high performance cars.

End of the day its the complete package that makes everything come together to give a car that has buckets of torque, great power delivery on low boost and isnt going to go bang.

Also you might want to have a real good look at a few other top Japanese engine builders like Jun etc and see what they do.

Are they doing it or have they done it wrong ??

These guys were pushing the boundries of the RB before most owners here were out of wetting their beds.

Its easy to say yes this is proven and thats proven but how many of you guys have built engines and own cars like these guys in Japan have built and still do.

Have you guys actually been and seen what the Jap top tuners build ???

For example in Australia how many 9 sec cars are there..Japan 10 years ago they were being pumped out left right and centre.

Nowdays hardly any and thats due to economic differences e.g Japan is going down the tube big time so nobody has the coin anymore.

Sadly the RB in Japan today is a dinasaur, alike to the old golden Holden 308 , yes parts are still available and the odd build still happens but this is due to just being for bread and butter money. The focus now and the in future is well and truly the GTR35.

At the end of the day you have to look at what Pauls building here. This is not a knuckledragger engine, its being built for all round high performance and high response so he can take it out to the circuit and go very quick but still enjoy a Sunday drive but have all sorts of anger under the loud pedal.

the rb is becoming a classic BUT what a classic it is :)

& yes the future for me will be the r35 as well - nowadays u can get them in the 90's so as soon as they a bit more, im onto it like a poo on blanket!!!

Off topic posts removed, this is Paul's thread, not advertising for a particular company.

Thanks guys

Thanks for letting me know.

Sorry of a bit O.T but I'm aware of another person with a high powered RB26 built by Racepace here that has had a N1 pump failure. He ended up rebuilding with a Tomei Oil pump. I'm also going to get a Tomei oil pump for my rebuild.

Anyone got any other suggestions of which pump to use?

Please do a search, there's literally dozens of threads on this throughout the forum.

Love the sound of those things :D, a little big for what I want out of the car :(

The goal is to make 450 kw BUT with 400 from 5000 RPM. I wasn't too far off with how it was before it went to heaven.

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