R33 Rb30 Conversion

[VHR32]

No, most charge a few hundred more.

SPS in Melbourne said yeasterday they can make whatever you want if you give them all your specs.

Approx $1700-1800 incl rings and pins. Im pretty sure they use Cosworth blanks?

[Cubes]

Thats what I thought!! I did a quick calculation and got 9.4 and was confused! Hmmm

Edit:

I just did a calculation on that webpage:

Arias

2 - 9.83:1 --> I got 9.1 ??

What c/r are they meant to be Cubes??

I dont know if any other pistons brands make a RB30/2# specific piston in 8.0+ compression and I cant be stuffed reading thru all the thread again!

EG: JE, Wiseco, Mahle.

How did you get 9.1?

See attached pic of the values I used for Arias piston 2 that gave me the 9.83:1 comp ratio.

[VHR32]

How did you get 9.1?

I put in 86.5, 85, 87 HG bore, 1.2 HG height, 65cc for RB26 (was a guess, some say they are 70cc? although CP measured some at 64.5cc avg) and 13cc dome.

= 9.12

Im picking up my RB26 head later today so i'll have to measure the cc's!

[Bl4cK32]

I put in 86.5, 85, 87 HG bore, 1.2 HG height, 65cc for RB26 (was a guess, some say they are 70cc? although CP measured some at 64.5cc avg) and 13cc dome.

= 9.12

Im picking up my RB26 head later today so i'll have to measure the cc's!

cubes and my rb25de head cc'd up around 62

[Cubes]

Yep exactly as what CP cc'd their heads up which is interesting..

62.5cc's.

[lukits01]

With regards to exhaust manifolds...

Its written in the guide:

In order to bolt up the exhaust manifold of your choice you must grind down the water galleys protruding lumps that run from the front to the rear of the block. They must be removed as they foul the exhaust manifold.

does this apply to stock exhaust manifold as well? silly question, would it work if I grind down the manifold instead of the block?

[Adriano]

Yes, this applies to the stock manifold, you are better off grinding the block, ,as it is only a small amount, and if you grind the manifold you will risk causing it to crack. P.S. im pretty sure an R34 manifold doesn't have to be modified, as it must be slightly different to an r33 one.

[sky30]

so who here has actually measured the bowl on a RB26 head?? what did it measure?

[Drift_Mulisha]

Im also interested in this, just about to order the acl ring set but wich set do i get? obviously the RB30ET rings would be beter as they are almost twice the price. can the RB30ET rings be fitted to the RB30E pistons?

Cheers.

Can anyone answer this? i asked it on page 230 but got no replies.....

[shanef]

Can anyone answer this? i asked it on page 230 but got no replies.....

did u get new forged pistons? (to suit ur head) caus ur rings should have come with ur pistons

[SirRacer]

if you want acl rb30e pistons with chromoly rings the part number is 6mkry2799

6kry2799 is normal without chromoly rings

[humz]

which head gasket can you use.

im buyin a rb25 metal head gasket off the forums, would it compatible.

also what sort of comp ratio would a 1.5mm head gasket give me on std pistons? and with 20thou over pistons? with a standard head.

[Craved]

Can anyone answer this? i asked it on page 230 but got no replies.....

im going to be running the RB30ET rings on the RB30e pistons, waiting on a ring compressor so i can put them in

im sure i'll be posting if they dont work

[VHR32]

which head gasket can you use.

im buyin a rb25 metal head gasket off the forums, would it compatible.

also what sort of comp ratio would a 1.5mm head gasket give me on std pistons? and with 20thou over pistons? with a standard head.

RB25 gasket if you have a R33 RB25 VCT head.

RB25, RB26 or RB30 gasket if you have R32 RB25 or RB26 head

http://www.csgnetwork.com/compcalc.html

Use this link from the previous page and work it out with what ever head you have.....

Edited November 14, 2006 by VHR32

[VHR32]

I was talking to a guy today who has just built a RB25 race engine and he suggests 9.0:1 is too high and I would only be able to run 15psi with 98 octane boost and not alot of timing. Is he full of it???

Is a GT35/40 with a .63 external gate way too small for a RB30/26 (9.0:1) track car? Im wanting 300rwKw.

This guy uses a .63 GT35/40 on his RB25 8.5:1 making 340rwKw on Elf fuel. He was running a .82 but was bit too laggy for him. (Seems a high power figure......)

Edited November 13, 2006 by VHR32

[humz]

thanx for that VHR32, awsome site. but i dont know any of teh following values.

head is rb25det VVT out of r33.

Bore/Stroke Designation Type?

1 = Inches 2 = Millimeters

Cylinder Bore Size

Piston Stroke Length

Head Gasket Bore Diameter

Compressed Head Gasket Thickness

Combustion Chamber Volume In CCs

Piston Dome Volume In CCs Negative For Dished Pistons (Use '-')

Piston Deck Clearance Negative If ABOVE Deck (Use '-') :

[Cubes]

I was talking to a guy today who has just built a RB25 race engine and he suggests 9.0:1 is too high and I would only be able to run 15psi with 98 octane boost and not alot of timing. Is he full of it???

Is a GT35/40 with a .63 external gate way too small for a RB30/26 (9.0:1) track car? Im wanting 300rwKw.

This guy uses a .63 GT35/40 on his RB25 8.5:1 making 340rwKw on Elf fuel. He was running a .82 but was bit too laggy for him. (Seems a high power figure......)

No one that I know of has really played with a .63 GT35r. But given the turbine maps on garretts web site the gt35r .63 flows roughly the same on the exhaust side as the gt30 .82.

The GT30 .82 I know can make 330rwkw odd on a built motor 9:1 on decent fuel, cams, plenum etc; made 580hp on the engine dyno.

So quite possible.

[r33_racer]

well we had 365rwkws before we spun a few bearings. But with full slicks same size as supercars use 280X680X17" we could spin them in 1st, 2nd and 3rd that was with a gt35r with .82 rear running 1.5bar. Thats when the tyres were upto operating temps too...the power was really savage in that it was coming on really really hard, also had the water inj too. We run shell 100 octane, stage 1 tomei cams, greddy plenum and 6boost hotside.

And you want to run a .63 rear gt35r. I think the best variation for a track car would be the 1.02 rear for the gt35r, unless there is something slightly bigger from hks above the .82 but below the 1.02 cause its still abit snappy when you have descent power. Plus some form of throttle controlled boost as stated a while back would be great.

[Cubes]

Some of the VLT boys who use their car on the track opt for the 1.06 gt35r rear as they too say the .82 comes on too hard.

[VHR32]

And you want to run a .63 rear gt35r. I think the best variation for a track car would be the 1.02 rear for the gt35r, unless there is something slightly bigger from hks above the .82 but below the 1.02 cause its still abit snappy when you have descent power. Plus some form of throttle controlled boost as stated a while back would be great.

I want to run a .82 with my RB30/26 but the guy who uses the .63 on his RB25 said his .82 was too laggy out of corners and the .63 fixed that.

A 1.06 would be good to make some big power though....