Crank Strength And Upgrading Options.

[Gerg_R31]

i'm doing a big N/A build and would definatly be interested in this

keep us updated

[R.I.P.S NZ]

Just to add to the discussion on standard cranks, rpm limits, power they will hold etc.

Our original 240z RB30 with a totally stock block (no filler or braces) stock crank, stock mains cradle and used mains bolts, did a full season last year running reliable 8s in street trim, it was pulled down end of last season, not a mark on anything, even re-used the same rings and bearings, changed the turbo, wound it up some more, rev it to 10,000rpm at times, run to 9200-9300/1000whp at the strip and we've just run an 8.36 still untouched.

This motor has had 2 oil changes only, still on its 1st set of plugs etc.

Don't underestimate the strength of stock parts!!!

Rob

Edited January 5, 2009 by R.I.P.S NZ

[[200]]

Out of interest what kind of lubrication setup are you using in respects to sump, pump, restrictors ect...?

[R.I.P.S NZ]

Out of interest what kind of lubrication setup are you using in respects to sump, pump, restrictors ect...?

RIPS wet sump, tomei pump and restrictors.

Rob

[[200]]

Thank you.

[darren lewis]

Thank you.

the stock 30 crank is a good piece. great quality steel, use one of our crank collars on it, drill and tap the oil plugs, all clearances to spec the things inmy books would do 700/800 engine horsepower. not an issue. www.lewisengines.com.au

[rockabilly]

yep top cranks, i run nearly 800bhp @ the fly done 6000 miles on it now amd been to 8350 rpm on track no issues yet, arp studs, std crank/cradle all balanced, spool rods, cp slugs,acl bearings..well happy..bernie uk.

[Dynamix]

Curious as to what rpm/hp are suggested for the spool rb30 conrods.. with stock motors cheap and rod/pistons/studs/bearings good value these days i dont know how you can beat the rb30/26 combo..

[bubba]

Curious as to what rpm/hp are suggested for the spool rb30 conrods.. with stock motors cheap and rod/pistons/studs/bearings good value these days i dont know how you can beat the rb30/26 combo..

After mucho research and asking of opinions, I have come to the conclusion that ~300rwkw & <7000rpm for stock rods (so I'm only shooting for 300rwkw and limiter is set to 6800rpm).

I figure that's pretty safe for now.

[Spoolup]

SPOOL Subaru 83mm Stroker Crank.

CA18's will be here May and the RB34's June hopefully :-)

[bubba]

SPOOL Subaru 83mm Stroker Crank.

CA18's will be here May and the RB34's June hopefully :-)

Nice!

[T04GTR]

so no ones broke an oil pump revving a 30 to 8000+ rpm????

[Spoolup]

Ive got a JUN pump - hits 8000 daily, for the last 18 months.

[N1GTR]

When you say "hits", do you mean bouncing off the limited (hard cut) or the limiter is set to 8200rpm (or thereabouts) and you rev it to 800 then shift before the ecu cuts it out?

[N1GTR]

Also for those of us that arent subaru heads, whats an 83mm stroke crank make the EJ turn into? I assume its for an ej25 block, so at a guess, 3L?

[bubba]

Also for those of us that arent subaru heads, whats an 83mm stroke crank make the EJ turn into? I assume its for an ej25 block, so at a guess, 3L?

3L ej would be pretty interesting..!

[Spoolup]

I have the limiter set at 8100 now.

The customer who ordered the Subaru cranks uses them in the EJ25 blocks from memory - std stroke on the ej25 is 79mm, but I believe they can be used in the EJ20 engine also which is 75mm stroke std and they resleeve them out to 100mm bores.

So you end up with around 2.6 litres

Im no Subaru head either :-) so I may be wrong

[N1GTR]

Good news for Subaru fans out there!

Can i ask the price please? Also does it come with pistons and rods to suit? Or was it just a one off order? Id hate to pull up next to a 2.6+ litre STi, but if they're not a mass production thing the chances are minimal of that happening

Reason i ask about the jun pump is that my rb30 has one and ive always been cautious about the limiter, so its good to know what they can take (within reason)

[Spoolup]

The subaru stroker crank uses stock length rods, and a custom piston. So its a relatively easy build :-)

[N1GTR]

Good stuff!