R33 Rb30 Conversion

[Sydneykid]

Cheers for the speedy reply, always on the ball

So if going down the power porting route for the turbo, it would be better to get both sides done? (GT35R .86 exh)

Would there be much benefit in power porting the standard 25 inlet manifold, i'm referring to the bottom half. Would this affect the low down torque?

Power porting the compressor and turbine covers is not something I have ever considered. I have done cast iron exhaust manifolds, works very well. I have not experienced any restriction in an RB25DET inlet manifold or throttle body up to 525 bhp so I doubt that it would be worth the cost. Over that, an RB26 top end with inlet manifold is a cheaper proposition when you add it all up. If you are intending to use the GT35R to its potential, then that would be my suggestion.

Hope that helps:cheers:

[Alf]

I removed all the clutch packs etc from the GTR transfer case in the weekend so I can convert the box to 2WD.

Im curious, is it hard to covert the 4wd box to rwd?.

What's involved?.

The 4wd box would be stronger in a 2wd set up?

[GTR-Ben]

Im curious, is it hard to covert the 4wd box to rwd?.

What's involved?.

The 4wd box would be stronger in a 2wd set up?

Well I havn't had it running in the car yet.. and it will still require a bit of a sledge hammer tap to fit the box into the S13 tunnel

It's not the best thing to do but I thought I would try it because I had a broken transfer case sitting there...

I basically removed everything from the output shaft and left the speedo drive there.. then cut the side of the case off and welded it all up. It's not pretty, but I think it should work ok.

I believe you can use a Z32 nose cone.. but I'm not sure what they do about the shifter when they do this.

This box would now be similar to a RB25DET box.. but GTR boxes are a lot cheaper and easier to find than an RB25DET box..

[Sydneykid]

The internals of the R32/33 RB25DETT gearbox and the R33 RB25DET gearbox are pretty much the same. I have seen no evidence that the GTR box is "stronger".

[raist60]

Gilly,

 

The RB's are interference motors. They WILL break valves if you snap a belt or skip several teeth.

 

Bl4ck32 previously snapped an idler bolt which snapped valves off, got pics.. Very nasty

I made the ever so clever mistake of having my timing belt off while bringing the motor round to 0 deg, lol.

And i can tell you my motor is not interference. As i was able to spin the crank freely whilst bringing it around to 0 which i actually did twice because i had missed 0 by a long shot the first spin.

So i would assume with my engine, (8.5 c/r, standard deck and head, JE pistons) is non-interference.

[Alf]

I made the ever so clever mistake of having my timing belt off while bringing the motor round to 0 deg, lol.  

And i can tell you my motor is not interference. As i was able to spin the crank freely whilst bringing it around to 0 which i actually did twice because i had missed 0 by a long shot the first spin.

So i would assume with my engine, (8.5 c/r, standard deck and head, JE pistons) is non-interference.

hrmm maybe you dont know the difference between an interference engine and a non interference engine.

Did you bring your flame proof suit :flamed:

[raist60]

Sorry maybe I dont

Interference: Pistons can meet valves when they are no longer spinning in sync

Non-Interference: Pistons physically cant reach the valves no matter what

Thats what I thought. Can you enlighten me?

[raist60]

PS. The flame proof suit comment you can stick up your ass. Ive got a 25/30 im offering some advice and you would prefer to argue and tell people they dont know shit.

Cheers

[Cubes]

lol raist60,

Is it possible for the lifters to bleed down while not operating hence allowing you to turn the motor over by hand and not cause any damage?

WDRacing said a while back the rb20t motor is not an interference motor as he has rebuilt his multiple times and the valves do not come in to contact with the pistons when spinning the motor over by hand.

BUT.. When Bl4ck32 RB20DET snapped a tensioner bolt his pistons smashed in to the valves.

My conclusion, when the motor is spinning over oil pressure pumps up the hydraulic lifters, this gives the valves more lift which will allow them to smash in to the pistons.

Piccy... This pot was the only one to actually break off but others had obviously been tapped as they were wonky.

[Cubes]

And a picture of the bore.

As you can see the valve recess in the piston has definitely been hit by the valves.

[RB30-POWER]

Are they the standard pistons in that motor above?

I will be running the NA pistons on my setup, they have the valve cut outs, so hopefully it will be non-interference.

[GTR32]

When Bl4ck32 RB20DET snapped a tensioner bolt his pistons smashed in to the valves.

Hi Cubes / Bl4ck32;

Do we know why Mr Tensioner Bolt decided to quit?

Cheers

[Cubes]

Are they the standard pistons in that motor above?

I will be running the NA pistons on my setup, they have the valve cut outs, so hopefully it will be non-interference.

Yes they are the standard RB20 turbo pistons.

They have the valve cut outs and the valves still smacked in to the pistons!!

[Cubes]

Hi Cubes;

Do we know why Mr Tensioner Bolt decided to quit?

Cheers

It had only recently had its 100,000km cam belt done.

It is suspected to have been over torqued.

Shaun @ Boostworx has heard of them going before so it appears to be at least known.

I replaced the tensioner studs when building my rb30 just to be on the safe side.

[raist60]

Dunno man, wouldnt think so. Maybe its the specific combo in my motor.

Didnt think lifters bled down all that much, the car was running that day, and ive never been able to "compress" a lifter by hand tool or otherwise (whilst experimenting of course )

[Bl4cK32]

yer...guy i bought car from had 100,000 service done. 106,000 idler bolt snapped off clean at the block. idler bearing had heat discolouration, and there was rubber dust inside lower belt cover.

I went through it all when building my new motor as i didnt wanna have it happen again....but a properly tightened std bolt is the safest bet

[GTR32]

yer...guy i bought car from had 100,000 service done. 106,000 idler bolt snapped off clean at the block. idler bearing had heat discolouration, and there was rubber dust inside lower belt cover.

 

I went through it all when building my new motor as i didnt wanna have it happen again....but a properly tightened std bolt is the safest bet

Just what you needed I bet. Good pickup on the dust.

Bearing seizure caused by overtorqueing then?

[Sydneykid]

I made the ever so clever mistake of having my timing belt off while bringing the motor round to 0 deg, lol.  

And i can tell you my motor is not interference. As i was able to spin the crank freely whilst bringing it around to 0 which i actually did twice because i had missed 0 by a long shot the first spin.

So i would assume with my engine, (8.5 c/r, standard deck and head, JE pistons) is non-interference.

You may have simply been lucky, the valves may not have been open sufficiently. So when you rotated the crankshaft. the valves where not protruding and didn't get hit. To test interference you really should put the crank at TDC and rotate the camshafts.

[MonstaS4]

I made the ever so clever mistake of having my timing belt off while bringing the motor round to 0 deg, lol.  

And i can tell you my motor is not interference. As i was able to spin the crank freely whilst bringing it around to 0 which i actually did twice because i had missed 0 by a long shot the first spin.

So i would assume with my engine, (8.5 c/r, standard deck and head, JE pistons) is non-interference.

I also done the above test, but i also done what SK suggested.....spin the cams with a piston at TDC......no interference. This is using standard RB30E pistons.

[raist60]

You may have simply been lucky, the valves may not have been open sufficiently.  So when you rotated the crankshaft. the valves where not protruding and didn't get hit.  To test interference you really should put the crank at TDC and rotate the camshafts.

Nah after I had a heart attack after realising and running around like a psycho swearing and cursing that id "broken my engine" I got my shit together and had a look where the cams where in their revolutions and there was an exhaust tappet sitting right under the peak of a lobe. lol it couldnt have been more open.

Luck is something I dont get...