R33 Rb30 Conversion

[RB30Classic]

Can I use the injectors from the RB25de and afm or will I need det ones as I couldn't find a flow rate for the 25de injector listed (If there is apologies but the whole thread is alot to retain)

RB25DE injectors are only 270 cc = 324 max hp (flywheel)

RB25DET are 370 cc = 444 max hp

I reckon if you're gonna build this engine it's worth aiming for 520 hp or 300rwkw.

It seems 480cc's are ideal before you need full sequencial control for good idle.

I have a Haltech E6K which only supports group or semi-sequencial firing.

The 480's are hard to find so I'm considering 550cc.

Good luck.

<{POST_SNAPBACK}>

Excellent thanks, are these engines reliable enough at that level of power with stock internals or will I need h-beam rods and forgies?

this thing needs to survive the NZ targa so it'll be getting hammered for 6 days of road racing. plus all the other daft stuff I'll be doing with it.

I don't want to build an expensive engine that's going to destroy it's self

[conan7772]

Excellent thanks, are these engines reliable enough at that level of power with stock internals or will I need h-beam rods and forgies?

this thing needs to survive the NZ targa so it'll be getting hammered for 6 days of road racing. plus all the other daft stuff I'll be doing with it.

I don't want to build an expensive engine that's going to destroy it's self

<{POST_SNAPBACK}>

I read somewhere stock prepped rods will hold up to 350 rwkw and pistons up to 320 but pushing it especially over a six day race !

There's quite a few RB30 DOHC's goin around now, heaps of which have stock internals and still going after 2 years of thrashing.

But racing is a bit different to thrashing.

You should read the DIY RB30 DOHC PDF.

It pretty much covers everything.

These web address is in post #3190

Edited January 30, 2006 by conan7772

[RB30Classic]

I've got the RB30DET PDF which is excellent by the way, but I prefer to get a couple of options before going out and spending a few bucks on a new engine.

Thats why I wanted a lower power level than is obtainable but need the reliability.

I get the feeling that what your saying is 500bhp is attainable and reliable enough for the petrol heads on this site to give a good paneling too. THAT WORKS FOR ME!

Righto 500BHP it is then, may the gods of tyre smoke and petrol fumes be kind!

I'm not after a 7500rpm red line but just strong power

[Cubes]

Ppls,

if you use the r32 rb25 n/a head please... please... please... stick a set of rb26 valve springs in there while the heads off the motor.

Mine apparently had 'good' seat pressure, so much for that, it is floating at 13psi at around 4000rpm.

Bugger.

RB30Classic, grab a good second hand rb30e, drop the rb25 head on it and have some stress free fun.

[mr_rbman]

Ppls,

if you use the r32 rb25 n/a head please... please... please... stick a set of rb26 valve springs in there while the heads off the motor.

Mine apparently had 'good' seat pressure, so much for that, it is floating at 13psi at around 4000rpm.

Bugger.

RB30Classic, grab a good second hand rb30e, drop the rb25 head on it and have some stress free fun.

<{POST_SNAPBACK}>

what are the gtr valve springs good for in term of rwkw's?

[conan7772]

Re: Front strut brace unable to fit.

After losing my front strut brace I noticed she's a bit looser in the front end on hard cornering.

Anyone mucked around with a triangulated brace and are they any good?

Edited February 6, 2006 by conan7772

[Bl4cK32]

what are the gtr valve springs good for in term of rwkw's?

<{POST_SNAPBACK}>

If using the std rb25de cams with the gtr springs Sky30 has 312rwkw(?)

If going aftermarket cams, match them to the springs u use.

[jnr32r]

How would you match the cam specs to the spring tension?

i intend to use my rb20 poncams on the rb25 and was thinking of upgrading the springs to rb26, but maybe should i consider other springs?

[jnr32r]

Ppls,

if you use the r32 rb25 n/a head please... please... please... stick a set of rb26 valve springs in there while the heads off the motor.

Mine apparently had 'good' seat pressure, so much for that, it is floating at 13psi at around 4000rpm.

Bugger.

RB30Classic, grab a good second hand rb30e, drop the rb25 head on it and have some stress free fun.

<{POST_SNAPBACK}>

What symptoms are u getting?

[Cubes]

jnr32,

Power goes flat after ~4000rpm and tends to read a higher than usual knock, its definitely not detonating.

Over at approx 5200rpm power will really die in the arse, lifters will pump up then it will run on what sounds like 4 or 5 cylinders.

Comes down to idle lumping over a little that then smooths out and returns back to normal after a few seconds.

Quite scary actually....

Shaun seems to think its a few things that make mine float earlier than Bl4ck32's or Sky30's on the same springs.

1. oil pressure... I have nearly 8kg/cm3 oil pressure at around 4000rpm+ where as the rb20det pumps have around 5 or 6.

2. My springs haven't been shimmed but did come up as ok seat pressure.

Bl4ck32's have been shimmed but does run the lower rb20det pressure pump, sky30's hasn't been shimmed and runs the lower pressure pump.

From memory sky30 say pump up around 17psi or something.

Bl4ck32 is running 16psi so he may yet see pump up.

Too many variables.

It was running so so rich with the gtr injectors in trimmed back to 58.5%.

Well in to the 9's as soon as it was on boost, as shaun said... Almost enough fuel to have it hydraulicing.

Light load and cruise was a little rich, then at around -5mmhg (where it drops of out closed loop, it 'may' be -5 i can't remember exactly) it went lean then once on boost it went rich. Tweaking of the base fuel map was definitely required.

Drivability and torque has improved shiet loads off boost, it now feels so so much better just before it comes on boost. Fuel economy is now down to around 10.6L per 100km's which is awesome.

[Bl4cK32]

I wont be going past 16 psi till i fit the new turbo with the new cams + springs

[mr_rbman]

well fingers crossed that i don't have this problem, for a while anyway as my valves were fully re done!

[jnr32r]

jnr32,

Power goes flat after ~4000rpm and tends to read a higher than usual knock, its definitely not detonating.

Over at approx 5200rpm power will really die in the arse, lifters will pump up then it will run on what sounds like 4 or 5 cylinders.

Comes down to idle lumping over a little that then smooths out and returns back to normal after a few seconds.

Quite scary actually....

<{POST_SNAPBACK}>

so is it the spring tension that pushes the oil out of the lifters?

I thought it was more to do with the oil pressures and design of the lifter that determined how fast the oil came out of them...

Does anyone know the spring tension rate on the rb20 vs rb26 valve springs?

[Cubes]

I am unsure of the exact workings but everything does play apart.

I may just have a collapsed valve spring or one that has gone weak as it does appear to have gotten worse over time ~30,000km's.

[[200]]

Does anyone know what pin size the CP Pistons have for the RB30?

[MarkE]

Im no longer building my RB30DET, so I'm offloading all my bits for the build up

Thought you might be interested. Got it all listed at :

http://www.skylinesaustralia.com/forums/in...howtopic=104606

Cheers,

Mark

[platinum]

heh - on a similar note; someone sell me an r33 s1 loom!!

[Cubes]

3rd gear let go this morning.. Idling out of a corner at low speed in third gear, light throttle off boost just cruising; loud bang then the huge thoughts of.... If I stop will I get going again?!?! So I managed to idle it back to home. :S

No real warning signs, the gearbox had a bit of a whine since I bought the car 140,000km's or 4.5years ago.

Possibly the last dyno tune with those long 4th gear windouts helped it along.

Still all in all I'm impressed with the gearbox's strength, its done a huge amount of km's and given quite a hard time.

I'll rip it apart and find out exactly what let go.

Any one know of a cheap rb20t gearbox in Adelaide?

I'm unable to drop a 25det box behind it due to finances, I need to get the valve float sorted first.. Priorities. lol

[sky30]

3rd gear let go this morning.. Idling out of a corner at low speed in third gear, light throttle off boost just cruising; loud bang then the huge thoughts of.... If I stop will I get going again?!?! So I managed to idle it back to home. :S

No real warning signs, the gearbox had a bit of a whine since I bought the car 140,000km's or 4.5years ago.

Possibly the last dyno tune with those long 4th gear windouts helped it along.

Still all in all I'm impressed with the gearbox's strength, its done a huge amount of km's and given quite a hard time.

I'll rip it apart and find out exactly what let go.

Any one know of a cheap rb20t gearbox in Adelaide?

I'm unable to drop a 25det box behind it due to finances, I need to get the valve float sorted first.. Priorities. lol

<{POST_SNAPBACK}>

I was wondering how long your box would last, I smashed 5 of the small MF5 gearboxes in under a year, most of them suffered the same 3rd gear problem( smashing the teeth off gear).

I would doubt that running your car on the dyno in 4th gear would have done any harm as using 4th or 1:1 is the strongest, the gearbox doesnt have to drive through the layshaftt.

[Cubes]

Ive picked up another 20t g/box... Lets see how long it lasts. :S

Such a pitty I don't have the $$ nor the time this week to grab a 25t box.

Little boys birthday this weekend, lots to do. :S

Fun fun fun...