R33 Rb30 Conversion

[lowlux]

Matlowth i work at crow cams and one of the grinders builds race engines,and his mate prep's things like blocks,rods,cranks etc for race cars and the price he gave me for "ME" to get it done is around 200, thats why its cheap like i said in my post.

[Cubes]

Really depends how much power you are chasing.

I'm only cleaning up the rods my self a little, clean up the inside of the block.

260rwkw in a R32 will be plenty and a CR of 9:1.

Especially having bugger all lag will make it very hard to beat off the mark. Providing I have wider tyres.

I don't want it to feel like the RB20DET where there is almost nothing then all of a sudden it snaps hard and wheel spins.

i.e in first i can push throttle from 1/4 to 1/2 and as soon as it comes on to boost in first it wheel spins.

Quite annoying as I usually for some reason in the heat of the moment tend to short shift in to second a little to hard and then second gear wheel spins up.

Simex tyres seem to help a lot but really I got sick of how badly they gripped in the wet and how soft and spungy around corners it made the car feel. The sidewalls are just to soft for handling.

I am running a bit of timing in her though when I drop the timing back to standard she doesn't snap hard but then it feels gutless.

I want some thing that is possible to feed on with good throttle control. I think the RB30 with a mild turbo will do that.

I know the RB25's feel a lot more progressive compared to the RB20's.

[matlowth]

Yep - but as mentioned by sydney kid, they'll give you sloppy compression ratio's.

I think the stock RB25det pistons give about 7.8:1 which isn't too bad... Don't quote me on that though...

matt

Originally posted by -Joel-

So it is possible to use RB25 or RB26 Pistons then?

[matlowth]

Ahh mates rates, thats different again... For Joe public however, that's the costs you have to pay.

matt

Originally posted by lowlux

Matlowth i work at crow cams and one of the grinders builds race engines,and his mate prep's things like blocks,rods,cranks etc for race cars and the price he gave me for "ME" to get it done is around 200, thats why its cheap like i said in my post.

[lowlux]

hey matt can u tell me whether u have to elongate the gallieries on the block or head? if its the block can u draw a circle of which one isnt lined up. And that block is very NICE! do u get it painted silver or does it look like that after being acid dipped?

[Cubes]

No you don't have to change anything lowlux.

[Cubes]

I've been having a bit of a look around on vct vs non vct.

I am seriously wondering if it is worth drilling out the RB30E block for the VCT oil pressure. Use a Z32 ECU that supports VCT and is mappable.

I read a post where some one stated the difference in the mid range for the non-vct RB30DET is buggerall compared to a RB25DET with VCT?

I guess any one who has had a RB25DET Then converted to the RB30DET would be able to answer that question

[lowlux]

nice one thanks joel,oh and another thing would the rb30 block bolt upto the rb20 5spd gearbox? cause i know the clutches are different,maybe a flywheel change would be what u need???

[Cubes]

The RB20DET gearbox won't handle the torque.

I have heard of RB20DET box's stripping second gear when they hit around 240rwkw and around 210rwkw they start to do their input shaft bearing in.

The only option is to fit the RB25DET Box. Well worth the money.

[matlowth]

Re: the oil galleries, we used an RB26 head gasket (Which is fairly similar to the RB30 bottom end (no vct etc)... I can't tell you off the top of my head whether any modifications were required to make it fit, but to the best of my knowledge there wasn't any. BTW - Restrictors were put in to the head so that not so much oil was sent up there too...

The bottom end, nahh - after it was acid dipped, it was painted silver to give it that new look... I think it makes it come up really nice! The white pistons are a cool look too... It's almost a shame to put the head on the top!

matt

Originally posted by lowlux

hey matt can u tell me whether u have to elongate the gallieries on the block or head? if its the block can u draw a circle of which one isnt lined up. And that block is very NICE! do u get it painted silver or does it look like that after being acid dipped?

[matlowth]

If you want to know what mid-range torque and power of an RB30 looks like, here's a dyno graph. Note, this is only 14psi of boost, on the street the car runs 16-17psi, so it's making around 330-340rwkw.

Although it's in km/h, you can see that by around 4000rpm, it's making in excess of 200rwkw which equates to a very quick street car. Power drops off after about 6500rpm, but it still has over 280rwkw @ 7500 which is the redline.

BTW - The other plot (lower one) was torque... The car was dyno'd on an LS1 dyno day, and they obviously weren't expecting a piddly little 6cyl to make as much torque as it does which is why the reading is so high up on the graph

Cheers,

matt

[matlowth]

BTW - I've been offered a set of carillos' quite cheap, so I'm thinking of making the switch & then up the boost so the cars making around 380rwkw.

If anyones' interested, I'm probably going to offload the rods for about $500 which is cheap considering I paid about 800 for it in my car. They're only about 3000km old too.

Cheers,

matt

Originally posted by lowlux

yeah i know joel but i did say was for me and would be more for someone else, but even for $500-600 i rekon its worth it

[Sydneykid]

Hi Joel, sorry I missed you question on the cambelt tensioner and idler pulley. There is already a threaded hole in the block for the idler pulley, well there has been on the 7 X RB30 engines we have done. So there should be one on yours as well. The position of the tensioner is OK for the Dayco cambelt. But I would check yours before you drill and tap just in case.

Hi matlowth, nice power graph, was that in 3rd gear of 4th? Do you know exactly how many kph per 1,000 rpm? I would like to compare with our engine dyno results on the first RB30/25 we did. So I need the rpm. It may help me with some unanswered questions I have in my head about our current RB30/26 that's almost finished. Yours is making around 550 bhp so the comparison is very helpful.

The RB30/25 made 510 ft lbs at 4,500 rpm but it had more that 450 ft lbs from 2,750 rpm to 6,500 rpm. Max power was 520 bhp at 6,250 rpm. The standard RB25DE cams and/or the turbo were holding it back a little bit as it tapered off rapidly after 6,500 rpm.

We can only use around 600 bhp or so, but I am looking for a bit more response from the RB26 multiple throttle butterflies and a set of 264 hi lift cams. Plus the rods and pistons are a bit lighter and the exhaust manifold will be a fair bit better, with equal length runners this time.

Oh I almost forgot, the T66 hybrid you are running, did you do a ball bearing and shaft upgrade on it?

Thanks for your input, its greatly appreciated

[JNR24]

Ok there still seems to be some confusion as to what pistons & rods & crank you should use to achive a desired CR of 8.5:1 - 9:1

Can someone clear this up? e.g RB30 rods with RB25/26/30 NA/DET pistons?

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Secondly, i am still in the stages of block preperation as we all know. Now after taking all the dags off and polishing everything up, i am now ready to send the block off to get machined/cleaned.

Now my particuler RB30 Block is on its second rebuild. Because the boreing process is increased in .10 increments & my motor has allready been oversized by .10 so this means that i will take it out a further .10 bringing it to a total of a .20 oversize over stock. (good idear to check this before you buy a RB30 Block and bring it home, as my motor will only be good for another rebuild, before you start running into heating problems, and issues with distorting cylinders). will this total bore of .20 bring my total engine displacement out to 3200ISH CC?

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Also while your motor is at (INSERT YOUR MOTOR MACHINIST HERE) its a good idear to have all the centre jernals given a light hone & re-lined so that the crank sits dead straight. This prevents un-even wear on your bearings. So this is what i have at the moment:

(Guide FYI)

Machine & hone out on all 6 cylinders: $150 / $25 per cylinder.

Balancing of crank : ??? iam guessing around $70-$100

Acid clean:$70 ISH

Alligment/Machining of centre jernals: $100 ISH

So this is basicly everything you need for the BLOCK!

Note: to balance the crank or the centre jernals, i think you need pressure plate/flywheel & harmonic balancer that your going to use. so that they can balance it properly.

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Ok what i also need to know about is Oil!!

What sump & pump works best!?, and will they fit without having to be modifyed?

Cheers guys!

(Gees, this threads coming allong nicely! theres some great info in here! )

[lowlux]

Well skyrine_dave i could never put in a rb26 for the money im doing a rb30/25 because i work for a automotive company the parts uses are basically cost price, like i mean the whole block prepped ready for the head will cost me under $1000 thats with NEW pistons and plus the head i can for around the 500-1000 mark now thats nowhere near the 6k+ u need for rb26

have i made a good case??

[sik32]

can anyone give me a power rating for rb30 NA bottom end (na pistons rods etc) with a NA 25 head?? what can na piston withstand??? for turbo application.

[Skyrine-Dave]

very good case lowlux

i hope there si going to be some explanations in this word document.. i have read too much different info

like whether to use the NA head, or the turbo head, what valve sprngs to use, what cams to use, what rods and pistons to use, what crank to use... etc

[Steve]

Originally posted by lowlux

Well skyrine_dave i could never put in a rb26 for the money im doing a rb30/25 because i work for a automotive company the parts uses are basically cost price, like i mean the whole block prepped ready for the head will cost me under $1000 thats with NEW pistons and plus the head i can for around the 500-1000 mark now thats nowhere near the 6k+ u need for rb26

have i made a good case??

And the 6k+ is for a second hand donk.

[matlowth]

I think you misunderstood me there

What i meant, was that the RB30 (in exactly the same state of tune as an equivalently prepared RB25 short block in your car is going to cost you around 2-3k more.

If you only want 300rwkw you're wasting your money paying for the extra capacity.

Just trying to save you money

Cheers,

matt

Originally posted by JNR24

now for a extra 400 bucks you can have a 3 liter bottem end & reap the benifits of doing it. And yes, performance does cost money your right matt. You only get what you pay for. you still looking at $2000-3000.

[Cubes]

If you only want 300rwkw

scofs.... only 300rwkw.

I'd be more than happy with only 300rwkw.

Thats double the power I am making now, I can imagine the feel as you feed your foot in to it coming out of a corner.

waaaaaaaaawaaawaaawaaaaaaaaa note the extra w's they are the wheels trying to grab the road around 5500rpm.

oh. sorry there ppls got bit carried away.......