R33 Rb30 Conversion

[Sydneykid]

I went with the high drilling for the mounting on the 26/30 but with no time to grab a second adjuster I fitted the belt as it was. While tight it wasn't too tight for the Dayco belt so I kept it on. No adjustment needed.

Another reason for high mounting, we also only use one adjuster and one idler, no need for 2 adjusters.

cheers

[Scooby]

Is this where I get to say "I told you so"?

I did advise you to go for the high mount tensioner for very good reasons. I have no idea why people think the lower mounting is better.

You can use the RB30 engine mounts, but you have to modify them. The RB26 mounts are OK too, but they place the engine too high. Lower the engine, it solves all the problems you are currently having.

Another reason for high mounting, we also only use one adjuster and one idler, no need for 2 adjusters.

cheers

What swayed me is the reinforcing behind the stock location. It may be meaningless but it might not - granted I haven't heard stories of the high mount set up failing.

If I knew enough about the potential effect on susp geometry to lower the mounts, and it was a quick and easy, and I knew it would do the job, no problem. Making it fit without lowering is tedious but it's 'safer' if you're not a pro.

I thought using 2 adjusters was an advantage given the cost of idlers, as per the guide?

How do you set and measure the tension on yours? Still can't find a deflection value for the 20kg tension listed in the RB 26 manual.

I'm going to work on my tensioner mount.

Cheers

Edited April 17, 2007 by Scooby

[Cubes]

Scooby, the 20kg is in the r32 rb26 engine manual. In a couple of places. 100%.

[Scooby]

Scooby, the 20kg is in the r32 rb26 engine manual. In a couple of places. 100%.

Hi Cubes I know mate, found it ages ago. What I can't find is what to measure the 20kg against ie there must be a deflection value. It's currently one dimensional. Unless I'm missing something.

There's a hole about 5mm diam, left of where the second tensioner goes as per the guide. It's about 15mm deep. The stud that goes into the water jacket definately has only 9mm engagement?

Cheers

Edited April 17, 2007 by Scooby

[r33_racer]

I thought when i measured the hole after i drilled the last block...the vernier depth gauge told me something like 12mm....maybe im drilling in the wrong spot haha

No that wasnt to the water jacket...it was before i broke through...

Edited April 17, 2007 by r33_racer

[Sydneykid]

20kg is too hard to measure, I use 10 mm total (both ways) deflection with one finger force on the tension side.

Of course MY finger is calibrated.

cheers

[pssiii]

Great thread!

Once you taste RB30det, you can never go back!!

Sweeet

[fr0st]

I'm about half way (money wise) on my mission to collect parts for my RB30. I managed to pick up an RB25DET head for a decent price except I have to fit it up to an R32. I have a greddy copy plenum on its way which takes care of the intake manifold but I need injectors now

Anyone know if you can use the RB20 fuel rail and some GTR injectors instead of going to the side feed RB25 setup?

Anyone ever measured the spacing between injectors on both?

[r33_racer]

i believe you can buy a top feed rail to go on the greddy manifolds.

[mambastu]

You can use a GTR type rail or the 25's side feed rail on the GReddy plenum. I use a R33 GTR standard rail with RX injectors on mine.

[fr0st]

Thanks, exactly what I wanted to know

[@irborne]

do you guys know if valve springs made for the RB26DETT fit and work properly on the rb25de head, i will be using this head for my rb30 setup?

Edited April 27, 2007 by @irborne

[mr_rbman]

do you guys know if valve springs made for the RB26DETT fit and work properly on the rb25de head, i will be using this head for my rb30 setup?

depends on whether the heads from a 32 or 33

[K_Slide]

Hi guys,

Currently having my series 2 r31 rb30 block dipped then checked so i have come to the point where i need pistons. I know arias make a set but i saw in the guide of cubes that CP make a set which is supposed to give a 9:1 ratio but i have searched for a supplier to no avail. So i was wondering if anyone knows where i could aquire myself a set?

Also i am using a rb26 head and i am looking at turbos, has anyone used a set of N1 turbos before? This is my first build so i am not overly sure on how they would go on the rb30 (ie: when they would run out of puff early in the rpm range?).

[Cubes]

Hey ppls,

A bloke I know who runs on the same dyno as I + one of his mates have RB25/30's in their VLT's. They have been sorting the head oil supply issue's. Both run N1 pumps.

Initially using std restrictors the head was flooding.

2 x 1.1mm restrictors. Initiaily all seemed good until it was noticed they were getting lifter tick when getting off the throttle from a hard run on the dyno.

Off the head came again; 2 x 1.5mm's and all is good but it still does breathe a little. The bloke I know said 1.3mm would 'probably' be ideal.

Bit of a nightmare.

Those who run by Gary's oil restrictor table which states for the hydraulic head to block the rear and run a single 1.5mm restrictor up front. Have you noticed any lifter tick when getting off the throttle from a hard run on the dyno?

Is there a reasonable explaination why 2 seperate motors had the same issue with 2 x 1.1mm restrictors when having 2 1.1 mm restrictors should have more oil flowing in to the head than a single 1.5mm. OR maybe the 1.1mm restrictors reduce pressure within the head too much where as the single 1.5mm provides less flow but more pressure? argg confusing myself.

[r33_racer]

negative cubes...our first motor with n1 pump had back blocked off and 1 X 1.5mm up front with no ticking initially then we found out after a few races two of the lifters were shagged and constantly ticking we replaced them with some second handies out of a spare head and its been good ever since. However we now run two 1mm restrictors....luckily enough it doesnt bother a dry sump system.

Edited April 29, 2007 by r33_racer

[GTRgeoff]

Hi guys,

Currently having my series 2 r31 rb30 block dipped then checked so i have come to the point where i need pistons. I know arias make a set but i saw in the guide of cubes that CP make a set which is supposed to give a 9:1 ratio but i have searched for a supplier to no avail. So i was wondering if anyone knows where i could aquire myself a set?

Also i am using a rb26 head and i am looking at turbos, has anyone used a set of N1 turbos before? This is my first build so i am not overly sure on how they would go on the rb30 (ie: when they would run out of puff early in the rpm range?).

Send a message to Spoolup, who has posted in here. I used his Spool rods and CP pistons for what should be a 9.0:1 ratio. He also has a website attached in his sig.

[VHR32]

Hi guys, Currently having my series 2 r31 rb30 block dipped then checked so i have come to the point where i need pistons. I know arias make a set but i saw in the guide of cubes that CP make a set which is supposed to give a 9:1 ratio but i have searched for a supplier to no avail. So i was wondering if anyone knows where i could aquire myself a set?

CP

All compression ratios are based on zero deck height, 1.2mm head gasket (7.13cc), RB25 @ 62.5cc, RB26 @ 64.5cc. They assure me they have done alot of work to make sure the facts are correct.

p/n= CP-RB30/26-.20

Flat top with no valve pockets

8.2:1 COMPRESSION RATIO with RB25 head and bit less with RB26 head

21mm pin

1.280" compression height

Only stocked in 0.20 thou oversize but can be custom ordered in any size.

p/n= CP-RB30/26-.20-9.0

6.0cc dome top,

9.0:1 COMPRESSION RATIO with RB25 head and bit less with RB26 head

21mm pin

1.280" compression height

Only stocked in 0.20 thou oversize but can be custom ordered in any size.

*Care must be taken when using on RB26 with more than 11.5mm valve lift*

ARIAS

Suit RB30/26

p/n= AP332103

flat top

21mm pin

1.280" compression height

Only stocked in 0.20 thou oversize (86.5mm).

COMPRESSION RATIO 8.4-8.6

Suit RB30/26

p/n= AP332104

10.6cc dome top

21mm pin

1.280" compression height

Only stocked in 0.20 thou oversize (86.5mm).

COMPRESSION RATIO 9.2-9.4

Suit RB30/25

p/n= AP332105

13cc dome top

21mm pin

1.280" compression height

Only stocked in 0.20 thou oversize (86.5mm).

COMPRESSION RATIO 9.5-9.8

WISECO

Skyline RB30 w/ DOHC RB25det cylinder head

1.260" compresion height, 66.5cc head chamber, Dish top -11.3cc, 7.0:1 compression ratio, 21mm pin, 1mm gasket thickness, 1mm deck clearance.

K577M865 86.5mm

K577M87 87.00mm

ACL

6MKRY9608 (VL turbo)

87mm, -4.5cc dished top, 1.261" compression height, 21mm pin,

Standard RB30ET pistons are 7.8:1, with RB25 head it is 7.1:1

These are bumped up to 8.5:1 so with the RB25 head it may give about 7.5:1??

Using http://www.csgnetwork.com/compcalc.html I came up with 8.5 for VLT (spot on) and 7.6 with twin cam head with 64cc chamber.

I entered: 2, 87, 85, 87, 1.2, 64cc, -4.5cc = 7.6:1

BUT these have a lower compression height than the CP/Arias and im sure it stuffs up my calculations....

[R32 TT]

Hi Guys,

I suppose there are not too many of you running twin low mount turbos on an RB26/30, but can anyone give me some advice on the turbo returns? The VL Block has only the one oil return in the side of the block. Would this be sufficient to t-piece into and run bloth turbos back to it?

Also, what about running a small 'catch can' under the turbos which collects from both turbos and then drains into the block via this one fitting... or is this completely unnecessary...?

[shanef]

Hi Guys,

I suppose there are not too many of you running twin low mount turbos on an RB26/30, but can anyone give me some advice on the turbo returns? The VL Block has only the one oil return in the side of the block. Would this be sufficient to t-piece into and run bloth turbos back to it?

Also, what about running a small 'catch can' under the turbos which collects from both turbos and then drains into the block via this one fitting... or is this completely unnecessary...?

hey buddy,

i'm running N1's for the first little while and then changing to GTRS's. What i've done is jsut t-pieced the lines into the single line on the block

i would grab some pics for ya, but the motors currently in the car for the dry sump and exhaust fab