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call me 'mr thorough' or a pain in the butt

ive been researching parts for my rb30 build for over 3mths now, finally coming together though

that makes me feel more comfortable - thanks for that superjet!

higher duration determines when the power band starts?

higher lift determines better air flow?

I would have thought that if you spent 3 months doing research you would have had some time to use the search button on SAU?? mebe even look at a few of the RB2X/30 conversion threads?

so this was originally posted by SK or Cubes (pritty knowledgable guys, been round for ages) and in the RB30 conversion section:

The answer on duration depends on what RPM range you are targetting, be realistic.

If you intend to use 7,000 to 9,500 rpm, something around 272 to 288 degrees would be the go.

For 5,500 to 8,000 rpm, around 260 to 272 and for 4,500 to 7,500 rpm then 248 to 260 is the go.

That's a simplification, but you get the idea. As for lift, once I know the effective rpm range,

I then choose the highest lift I can for that duration.

What valve springs you are using will also determine the maximum lift

Quick hint to warlord - take your foot out of your mouth before it gets buried deeper, somtimes people feel like a new start and join date/post count has no bearing on what actual knowledge they bring to the conversation

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i did search the forum and the only info i could find was exactly that post from SK, i wonder if these rules still apply though as it doesnt correspond with the advise i was given, i then asked an rb30 specialist what i should go for if i want strong midrange and big topend and he suggests 280's BUT SK states they are good for 7500-9500rpm. i highly doubt anyone here knows rb30s better than rips...so now u know the motivation behind this thread!

re. warlord pls keep this off the thread as many of us here are interested in cams, not personal opinions

ive decided to run with 280degree cams & 11.5mm lift on my rb26/30...after speaking to a particular source, the god of rb30's :D

:P

street car?

idle?

lag.......

brake booster vacuum...

shims, buckets, springs, head modification.

enjoy

Can't/wouldn't bother arguing with RIPS. :P

Im sure RIPS has already shown you a few vids but the RB30DET he built up for the black R34 was running 280degree 10.8mm cams.

The RB30's soak up big cams nicely. :D

With regards to various durations, where peak lands and usable RPM - as your probably aware inlet tuning (manifold) plays a huge part. RIPS always run a custom plenum.

Edited by TheRogue
I'm running a pair of 264 [email protected] 9mm (110/115) cams at their std centrelines in the rb30det with a 9:1 static comp, ported/polished, deshrouded head.

So you are running the 423A cams? I have been trying to find out if the 423B cams require any head mods or new valve springs but have not been able to get an answer. I should just ring them but being OS and different time zones makes it difficult

that black 34 is a beast, aka ST3LTH! how do u know it has those cams?

10.8mm or 11.5mm was recommended

Can't/wouldn't bother arguing with RIPS. :P

Im sure RIPS has already shown you a few vids but the RB30DET he built up for the black R34 was running 280degree 10.8mm cams.

The RB30's soak up big cams nicely. :D

With regards to various durations, where peak lands and usable RPM - as your probably aware inlet tuning (manifold) plays a huge part. RIPS always run a custom plenum.

  • 3 weeks later...
hi guys,

im looking at purchasing cams from http://www.camtechcams.com.au/ & valve springs from http://www.performancesprings.com.au/.

pricing has attracted me & i've heard some good things about both products to date, im also aware that some engine builders use these brands.

how do they rate in terms of quality & performance versus the likes say jun, hks, tomei?

regards

marko

im about to test some camtech cams over the next few weeks, ive heard great feedback and im sure they are just profiled off popular grinds anyway...... I tried a few sets of crow SR cams awhile back and i wont go there again.... disaster.

as for valve springs for your rb or sr stay away from the ones you listed...... they soften up way to quick. Ive been burnt a few times now and since switching back to Ferrea / Brian Crower and the jap gear ive had ZERO issues. We used to use a lot of the performance springs in the v8's we built (big solid rollers) and even then they required swapping out more often than the us-of-a stuff. Then again thier the cheapest and most shops make good coin outta them....

Just out of interest from those who are using them have they had the springs tested after they were removed? i have some kelford ones here for a 26 im about to have tested (done one full season) it will be interesting to see how they fared.

Edited by URAS
fitting 280deg cams, wiv big lift,,, get the die grinder out son!!

Is it worth going that big on a 26/30 with 8500 rev limit..?

RIPS runs 280 10.8mm cams so they are proven to make the numbers ;-)

Mine will see street use and drags and I am running a C4 auto with 3800 stall, so does that make cam choices harder??

What cams did you end up going with as Im starting to look for 26 cams also.

What work was needed to fit 280 degree cams and what springs did you use.

Cheers

i stuck with the 10.8mm lift as suggested by my engine builder & rips - once u go to 11.5mm lift a lot more grinding is required as well as buckets & shims

with the 10.8mm lift grinding was required to accomodate the extra lobe height

if performance springs are good enough for my engine builder & others that have used them with solid results, they're good enough for me

  • 4 weeks later...

i had the 10.8's fitted with no trouble at all (only required some head machining to clear the cam lobes) & valve springs were fitted to match.

what info were u after as im happy to help :) no secrets here

im not sure about the part but i can find out if u like.

retainers & valve guides were good on my head as it was a virgin & didnt do many kms so there there no need to change them over

i had an extensive head port done by proengines.com.au, i'd recommend u speak to greg although he is not back till next week...very helpful & likes to chat once u build rapore with him

Did you end up going with performance springs? or the jap stuff?

seeing as the prices are 2-3x more is it worth it?

Camtech do a spring and titanium retainer set... might be worth a call? we have used 2JZ ($550rrp) and SR20 ($450rrp), im yet to use their RB kit so im not sure of the price.

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