R33 Rb30 Conversion

[discopotato03]

Just a thought it would be interesting to know the weights of the various forged pistons too if possible .

Thanks A .

[Cubes]

My forged pistons felt lighter than the std items.. They were also much shorter.

[mark99]

These are rb 26 pistons 86.5mm bore; wiseco piston- 341.4g pin- 105.8g. Arias piston- 374.8g pin- 99.6g. CP piston- 305g pin-97.2g

[GTR-Ben]

RB30DET is in.. going to be an interesting bonnet.

[dnb]

looks so good!

ps go the colt 256 compressor. they dont make em like they used to!

[GTR-Ben]

looks so good!

ps go the colt 256 compressor. they dont make em like they used to!

Poor old girl is a spare. Sitting out in the shed.

[fatz]

gen i have half a husky at that pic... hot!

[Fitzpatrick Speed Works]

phantom

when the block are bored we always make sure the run speed is low ie the bore tool moves slowly up and down the cylinder giving you a finely hatched pattern about roughly 25-35 degrees to the horizon if you where looking straight at the bore from inside. As my engine machinist has now aquirred a torque plate honer i will be using that from now on although the difference is minute its still ensuring the best possible result.

discopotato03

with standard rod and pistons you can run the standard headgasket and using the headgasket on foges with my experiece with arias will give you around 8.6:1 comperssion using the hightops with standard rods, using the flat tops i believe its below 8 around 7.4:1. However the eagle rods being chev arent actually the correct length they are 6 inch not 5.92 that standard rods are and the sit above the deck height enough that you will need at least a 1.2mm headgast to acheive a squish and avoid valve isssue when running bigger camshafts. All this info is based on the 26head but its pretty much the same if you are using a 25 head, but the 20 head is different, correct me if im wrong i believe the cc of the rb20 head is 63cc and the rb26 is 66cc so it changes it all right there.

[Alf]

Would ceramic coated pistons increase the cr much?.

[MonstaS4]

Nope. The thickness of this stuff is in the thousandths of a millimeter.

As a side note, got my RB25/30 running last weekend It will get a basic tune next saturday so i can run it in.

[stav]

phantom

when the block are bored we always make sure the run speed is low ie the bore tool moves slowly up and down the cylinder giving you a finely hatched pattern about roughly 25-35 degrees to the horizon if you where looking straight at the bore from inside. As my engine machinist has now aquirred a torque plate honer i will be using that from now on although the difference is minute its still ensuring the best possible result.

discopotato03

with standard rod and pistons you can run the standard headgasket and using the headgasket on foges with my experiece with arias will give you around 8.6:1 comperssion using the hightops with standard rods, using the flat tops i believe its below 8 around 7.4:1. However the eagle rods being chev arent actually the correct length they are 6 inch not 5.92 that standard rods are and the sit above the deck height enough that you will need at least a 1.2mm headgast to acheive a squish and avoid valve isssue when running bigger camshafts. All this info is based on the 26head but its pretty much the same if you are using a 25 head, but the 20 head is different, correct me if im wrong i believe the cc of the rb20 head is 63cc and the rb26 is 66cc so it changes it all right there.

Who is your machinist, does someone in Canberra have a torque plate now ?

[smok74]

Grow up kiddies, do what Tony Reigoli (is that how u spell it? ) is doing and slap a RB26Dett head on the RB30 block. Then ya mongral donk will get crankin ! have fun.

[Cubes]

lol.. Smok74.

Its a matter of personal choice.

I prefer the rb25 head as it works better with my setup ad is cheaper.

[Fitzpatrick Speed Works]

i do have an rb26 head and so does ben!!!!!

[dnb]

Grow up kiddies, do what Tony Reigoli (is that how u spell it? ) is doing and slap a RB26Dett head on the RB30 block. Then ya mongral donk will get crankin ! have fun.

is that who pioneered the twincam 3l. wow i learn something every day!!!!!!!!!! NOT!

[Cubes]

The bloke who first played with a twin cam RB30 in AUS many years ago used to work at Turbo Tune. (remember that Zoom article?)

He now is the tuner for Blackwood Auto & Dyno.

[dnb]

i saw an article where a guy done it with a rb20 head a long time ago.is that him?

[Cubes]

Sorry.. no it wasn't..

I forgot about the rb20. lol

I remember one thing he said.

The stock RB25 head flows more than a ported/polished SOHC head. Considerably more. He had all 3 on the flow bench. RB20t, sohc & rb25.

[dnb]

im just wondering if anyone can confirm the location of the tensioner hole(above water pump)

is it exactly as described in the pdf file?

i have the 152 tooth belt

[Alf]

My appoligies for bringing up old stuff but I couldnt find any photos as most of the pics dont work anymore in older posts.

My engine builder hasnt seen my head yet but he tells me that the rb25det head rear passenger's side water jacket sits out past the block, the na rb25 head doesnt. I'm still scratching my head how he came to that conclusion when my head doesn't have this problem.

Now all kinds of thoughts are going through my head atm, do I have an NA head or are there variances in the 25 turbo heads, VVT is an obvious one (mines VVT) then I go on thinking do I have an na inlet manifold,cams and valve springs...:confused:

The pic below is my bare head, the orange arrow is where i've been told the problem is.

The complete top end came off a 33 gtst so I would assume it would be a turbo head.

In the past replies SK and Joel have used na heads, what are the characteristics of the na cams on the new engine? any problems with reversion etc....

Cause if I'm stuck with na valve springs etc..:slap: it maybe time for tomei pon cams and stiffer springs.