R33 Rb30 Conversion

[Craved]

im pretty sure the rb30 runs a 1.8mm.

but you will need to measure them, i doubt i could tell the difference between 2mm adn 1.5mm with the naked eye.

[overpowered]

just got a quick question or 2

will intercooler piping that fits a rb26 engine fit a rb30/26 setup in the same car? or will i have to extend the pipes the 40mm or so?

can i run the rb30 size head bolts with a 26 head? (this is a throw together engine while i build my other engine on the side so i dont care how long it lasts so if i can get away with 30 sized bolts that would be good)

Edited March 19, 2007 by overpowered

[Sydneykid]

Gary- The design is a fair compromise for room to make fit as i wanted to low mount the GT35. I wasnt too sure how well the wastegate pipes would work (again clearance limited) but it will run as low as 14-15psi boost. Im using a Blitz dual SBC to boost up to 17psi via the bottom port only, when i try and increase the boost more than this via the conrtller i get problems with unstable boost.

Im only running a 11psi spring in the gate, would this be the problem?? I have a 15psi spring to try.

I don't think you would have to change the external dimensions 1 mm. All you need to do is extend the collector away from the flange. All 6 cylinders have to have flowing access to the wastegate pipe.

The LOWER the boost, the BETTER the wastegate has to work. It has to allow MORE exhaust gas to bypass the turbine. Higher boost means less exhaust needs to be bypassed.

So, I don't think that the spring change will help much in controlling boost in this case.

cheers

[Sydneykid]

just got a quick question or 2

will intercooler piping that fits a rb26 engine fit a rb30/26 setup in the same car? or will i have to extend the pipes the 40mm or so?

can i run the rb30 size head bolts with a 26 head? (this is a throw together engine while i build my other engine on the side so i dont care how long it lasts so if i can get away with 30 sized bolts that would be good)

There is usually enough flex in the pipwork and length in the silicone joiners to accomodate the extra 38 mm of height.

RB20/25/30 head bolts are 11mm and RB26 are 12mm, despite the presence of locators, I would be reluctant to leave 1/2mm of float around the head bolts.

cheers

[@irborne]

need a favor: any of you guys have either CP or Arias pistons for your setup, would you post the number engraved on the underside of the piston?

[Alf]

Arias AP332104

[@irborne]

greatly appreciate it alf

[Godzilla33]

Hey Spoolup, you doing any special deals on your 9:1 cp's?

[Spoolup]

$2090 for pistons/rings and rods

$1350 for pistons//rings

plus freight and insurance

[Godzilla33]

Thanks,

Already got rods though, live in Bris so pickin them up would be no worries. I'll sus my options n work somthing out.

[Spoolup]

ok no probs - give me a call on 0402 351 688, need a couple days to get them in.

Cheers

[r33_racer]

The car got sorted and tuned the other weekend and we made 370rwkws again.

Will post the dyno graph when i get home, hopefully ill remember.

Edited March 22, 2007 by r33_racer

[sky30]

Nice result michael, keen to see the dyno graph to compare.

You running a GT35?

[fr0st]

I've decided my RB20 is no longer going to cut it and I'm keen on breaking my engine building cherry

The basic plan is a RB25DE head with GTR valve springs and a standard RB30e bottom end. The car (R32 GTS-T) already has a RB25DET box

Just so I'm under no disillusions before I start to collect parts -

Can a non rebuilt RB30E bottom end be expected to last at 270-300rwkw?

Is a metal head gasket and o-ringing a requirement for this kind of power with some reliability?

Can I skim the head (RB25DE/DET) a little to raise the compression closer to mid 8's without upsetting the quench zones? Likewise skimming the block to run a zero deck height?

Is it worth replacing the bearings and rings to after market items or will something else break first (rods?) making it a waste of money?

Will I need after market head studs like ARP's or will OEM do for this kind of power?

I think thats about it...

I know a lot of the reliability has to do with tuning but stock parts only last so long before they let go at high power levels. I'd honestly be happy with a responsive 250rwkw from a 'on the cheap' RB30 build but 300rwkw is my goal and probably the absolute limit for a R32 GTS-T anyway. I could probably do it from an RB25 but I want the extra torque to make a bit of a motorkharna weapon

Thanks in advance for the advice

[discopotato03]

Frost no doubt someone will confirm/deny but I think all RB26 valve train components are unique dimensions . Your call but the head will most probably make/break the final result . R33 and 34 RB25 heads have larger ports than R32 RB25DE and I would think R33 RB25DE heads would not be very expensive anyway . I can't see why it wouldn't be possible to not use VVT with a 33 DE head plus you'll need springs anyway . I dont think the weld mod to the water jacket would be expensive .

Just my 2c , cheers A .

[mr_rbman]

Frost no doubt someone will confirm/deny but I think all RB26 valve train components are unique dimensions . Your call but the head will most probably make/break the final result . R33 and 34 RB25 heads have larger ports than R32 RB25DE and I would think R33 RB25DE heads would not be very expensive anyway . I can't see why it wouldn't be possible to not use VVT with a 33 DE head plus you'll need springs anyway . I dont think the weld mod to the water jacket would be expensive .

Just my 2c , cheers A .

seeing as its going into a 32 your better off sticking with 32 25de head! Makes everything easier.

[overpowered]

good question above, will stock rb26 headbolts be fine for a 400rwhp limited rb26/30 setup?

[shanef]

good question above, will stock rb26 headbolts be fine for a 400rwhp limited rb26/30 setup?

yep, certainly will (block needs re-tapping to suit the extra 1mm dia of the 26 bolts though)

[r33_racer]

ok here are the sheets.

Just got back from first day of the first round of the state championship round at QR. Was good, but I was expecting more cars to be there...seems alot of people pulled out at the last minute....odd.

We need a good boost controller. And a better setup suspension.

[satanic]

As Craved asked... any place in Sydney to get ARP gear for cheap?

Also; any one know the part numbers for the tensioners required? NSK items I presume? Where to get them from?