R33 Rb30 Conversion

[Guilt-Toy]

mine is in the lower 8:1's as well, probly 8.1:1 with the 25 head, i am starting to think its a clearance engine.

my motor is a clearance motor and has a static comp ratio of about 8.3:1

[Risking]

typically no they are not a clearance engine.

Ive had belts fail on RB30's and its not particularly pretty.

Of all the 30's ive built and worked on none of them have ever been free runners.

[Guilt-Toy]

interesting....

how would i test to tell if my engine is clearance or not?

Edited January 13, 2008 by Guilt-Toy

[Alf]

As R33-Racer said u would have to have really low comp to make it "free running"

You would need serious bowl pistons or a lower top dead centre.

To give you an idea, a stock RB30ET is in the 7s and is still an interference motor.

To test it: remove your timing belt and crank the motor over by hand if it hits a valve you know the answer. keep trying this with turning the cams a few degrees and cranking it by hand, ull get the idea.

Out of all the interference motors with broken belts that have come in through work only 1% have escaped the carnage. There is a very small chance that when the timing belt snaps that the cam/s will be in the right position so all the valves will be shut/ clear the pistons.

Edited January 14, 2008 by Alf

[MBS206]

Alrighty guys,

Just went through the RB30DET faq again.

And I need to know HOW to lower the motor the 12 and 15 mm each side as required when running the stock 25 inlet mani.

Is it a matter of pulling the mounts out, and shaving 15mm off the bottom of each, or what?

[dano4127]

Perfect excuse for new plenum!!

[Al]

Perfect excuse for new plenum!!

Exactly

[mr_rbman]

took my car out for its first track day on the weekend and after my first session i found quite a bit of oil in the engine bay from my catch can. i have a stock built rb30 with rb25de head (non vvt) with rb20 oil pump and no restrictors. My catch can had a filter on top and 4 1/4" holes so i thought it was building pressure causing the oil to shoot out so i added 4 more holes and made them all bigger which helped but i was still getting probably close to 200ml of oil in the catch can after every 15 min session. Is there any way of fixing this without chucking the restrictors in the block? also incase it makes a difference the catch can is running off the two outlets on the cam covers.

Cheers!

[TiTAN]

Plumb in a return to the sump?

[GT-RZ]

picking up an rb30 this weekend and 25 head. just reading through the pdf file for the conversion it mentions that i need to make sure the block has provision for the oil/water return and that both lower tensioner locations are machined flat. this engine is coming out of an R31 GXE i believe. any know if this engine will have the above? don't wanna buy something i can't use.

[benm]

My '89 RB30 out of a Silhouette had everything just with bolts in place, remove the bolts and its ready to use.

[Guilt-Toy]

plazmaman plenum still hits the bonnet.

Exactly

[dmac_25]

Hey all,

Just chucking this out there could it be possible using the rb20det head getting it ported and putting bigger valves in it just reading the pdf and could it be possible putting in the 25 valves and make it work?

Because i have a rb20det head out of a wreck and a rb30e out of another one.

Just chucking it out there to see if it possible?

Regards

[Al]

plazmaman plenum still hits the bonnet.

That sucks, GReddy FTW!

The factory plenum shouldn't hit the std 33 bonnet only hits the strut brace. Since i use my car for track/motorkahna days i wanted to keep the strut brace and went for a GReddy plenum.

[GTRgeoff]

26/30 FTW

[mr_rbman]

Plumb in a return to the sump?

mmmm, hoping for an easier way.

[Guilt-Toy]

I think he means to try plumbing a return from the catch can to the sump. mine is setup like this

mmmm, hoping for an easier way.

[[200]]

What are people paying to get their bottom ends built up?

I was quoted for the following,

$220 to balance rods and crank, extra $55 for flexplate

$375 to change from 11mm head studs to 1/2"

$75.90 to crack test the crank and check grind

$82.50 to linish the crank if needed

$400 for tunnel bore and check main bearings

$190 for a rebore

Anything else?

[shanef]

usual price ive seen is around $1800

[MBS206]

So, are people actually going to answer the question, not give bullshit responses?

How exactly can you fit the RB25/30 into the R33 GTS-t WITH a strut brace fitted, and NO, I'm not putting on a new plenum.