Rb30 cylinder head work

[tridentt150v]

Would twin cam work better?  ie anRB25de head?  It has to breathe better surely?

 

[Ben C34]

8 minutes ago, tridentt150v said:

Would twin cam work better?  ie anRB25de head?  It has to breathe better surely?

 

That's a seriously more sensible option than spending any money on the 30 head. I guarantee people who want to be different are deluding themselves. There's a reason basically no one bothers with an na rb30, especially spending money on it

[Diko31]

Undoubtedly twin cam would be better, id go with a 26 head, ive found a thread on building a rb30 with a 26 head, but i havent read it. Its what i do want to do down the track but if a rebuilt 30 head is gonna cost as much as a 26 head conversion then yeah, im gonna go with the conversion. You both clearly know more than me so if you think its more sensible to go with a 25 head rather than a 26 head then obviously im gonna take your advice and go with a 25 head. not sure if they made NEO 26 heads but a NEO head would be the way to go regardless, yeah? 

I also do plan on converting both my wagons to twin cam so yeah, illogical to work towards anything but that. 

 

And again, i appreciate your help and any help that is given in the future! Thank you

[Diko31]

And if you think its more sensible to work towards the head conversion rather than working the standard head, then advice is taken! As i said, twin cam conversion is what i want to do with both my wagons down the line so maybe its best to just start there 

[GTSBoy]

Seriously, unless it has to stay NA, DO NOT DO ANY WORK ON THE ENGINE. . . . NOTHING.

If you want it to be fast, put a turbo on it. Case closed. If you want to be different and fast, put a supercharger on it.

An engine conversion to a LS1 would make more sense than doing anything at all to an NA RB30.

[Diko31]

Rb26 head supercharged it is then 

[admS15]

Ls1 ls1 ls1...

[Ben C34]

8 minutes ago, Diko31 said:

Rb26 head supercharged it is then 

Rb25 head. Need the vct.

[Diko31]

Are you saying that i need the rb25 head external oil feed for an rb26 conversion or?

[Ben C34]

1 hour ago, Diko31 said:

Are you saying that i need the rb25 head external oil feed for an rb26 conversion or?

I'm saying the 25 head is the better choice due to having vct.

[Diko31]

Aaaah okay, is it less work to chuck on a 25 head to? 

[GTSBoy]

No, it's more work, because you have to make the external oil feed for the VCT.

Just a question. How much money are you willing to spend on not going fast?

[Diko31]

You made me laugh with that last comment hahahaha ?

Well to be honest, i havent got a budget in mind because everything's gonna be happening over time. And im not saying within a 6 - 12 month period. I dont value money like most people, so i dont feel as bad when im "wasting" it...plus cars cost alot when modding and upgrading "properly", so theres that

I have a feeling top end is gonna need new standard gear soon, i can here a tick coming from the rocker cover and i know its not the usual tick that rb30s are prone to...so i might just ditch the NA aspect. Im feeling a supercharger in my daily. Not sure how much the stock internals of a rb30 can withstand but i hope its a decent amount. 

[Diko31]

The tick sounds like excessive wear on the rockers or lifters. Possibly even springs. Could be the lot. If i replace all that, may aswell buy new valves, new cam, and get the head bathed

[Diko31]

If it dont cost too much, ill see how much it is to shave a mil or 2 off the head to increase compression but im pretty sure that would involve shorter valve stems 

[Diko31]

Higher compression means the engine will need more air flowing through into the chamber, yeah?

[Diko31]

Ive got a spare rb30 just laying around to so ill just build that into a rb26/30 

[Diko31]

Also, thank you for havin a good yarn to us about it

[GTSBoy]

9 minutes ago, Diko31 said:

I dont value money like most people, so i dont feel as bad when im "wasting" it...plus cars cost alot when modding and upgrading "properly", so theres that

In that case, either piss or get off the pot. Don't stuff around. Build a 10000rpm screamer. Full house OTT polish and balance everything to the nth degree. 6 throttles with open ram tubes, handbuilt extractors. 300° cam, 13mm valve lift, 11:1 compression and E85.

12 minutes ago, Diko31 said:

I have a feeling top end is gonna need new standard gear soon, i can here a tick coming from the rocker cover and i know its not the usual tick that rb30s are prone to

These things have hydraulic lifters. Just sayin'.

13 minutes ago, Diko31 said:

Im feeling a supercharger in my daily. Not sure how much the stock internals of a rb30 can withstand but i hope its a decent amount.

This would be a fine way to waste money. No supercharged engine is ever as good as an equivalently turbo'd engine, but it is a different sort of fun. Noise + insta-boost is always fun.

10 minutes ago, Diko31 said:

If it dont cost too much, ill see how much it is to shave a mil or 2 off the head to increase compression but im pretty sure that would involve shorter valve stems 

Not sure how shaving the head means that you need shorter valve stems. Are you thinking about the right things? It's not like it's got pushrods. The cam moves up and down with the head, and everything in it, no matter how much you chop off the bottom.

10 minutes ago, Diko31 said:

Higher compression means the engine will need more air flowing through into the chamber, yeah?

No, higher comp means it will make more power. The swept displacement remains the same (unless you bore &/ore stroke it). The head flow remains the same (unless you do something to the head &/or cam). So, the air flow will remain essentially the same. It's just the extra compression drags more power out of the same amount of fuel and air.

9 minutes ago, Diko31 said:

Ive got a spare rb30 just laying around to so ill just build that into a rb26/30 

An NA 26/30 sounds like a good idea. But a 2JZ swap is probably more interesting.

7 minutes ago, Diko31 said:

Also, thank you for havin a good yarn to us about it

No problem. I'm not actually out to stop people from having fun modifying stuff - but it is sometimes necessary to mention where efforts are wasted vs. where efforts will return benefit.

[Diko31]

Yeah nah, i wont be doing work like that at this stage. Maybe in the far future when ive got drift skillz

Okay so hydraulic lifters dont wear out then im guessing

Thats why i said id supercharge my daily. Cause i love the sound and the concept over a turbo. My driftpig will be turboed because well, they provide alot more power than a supercharger

Wait yeah, i thought that through wrong, valves arent at max lift when pistons are at tdc ?‍♂️

Okay so ill definitely be shaving the head. Do you reckon advancing the timing a couple degrees would be worth while, or just leave as is?

I want to build an NA engine because i want to see how much power i can get out of an NA rb. Not many people do it, and i completely understand why, but boy do i love my rb's

I know youre not man, hence why im acknowledging what youre saying and taking your advice with most of what youre saying. But when it comes to how i want to boost my daily, whether super or turbocharged, its pure personal preference. i now realise though, after listening to what youre saying, boosting is the smarter thing to do.

Im not sure about you either, but the sound a worked NA rb30 makes, when its screaming off its dick, sends shivers down my spine