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ok just thought id share some info

Mate and i rebuilt his rb20 with:

aries pistons

stock rods

stock manifolds

630cc injectors

ltx12s mircotech

gt3540 with 1.06 rear (off typhoon xr6)

walbro pump

jun cams and cam gears

We ran outta fuel but so far tonight screwing around on his dyno in matrix mode made with an inconsistent, 10.1 AFR towards the end of the rev range on 14psi without touching ignition timing yet it made 240rwkw...2psi at 4grand and builds very quick from there. Already the curve is very strong. previously without the cams it made 250.1 on 20psi. we are very interested to see what it makes tomorrow.

Will keep you all posted on the results...i just thought id post this up just incase you care.

I have two charts i will post up later tonight..

cheers guys

Edited by Ryanrb25
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So your talking what, 20psi in by... 5000rpm? 5500rpm?

2psi @ 4000rpm i cant see building to 20 all that fast :P

Interesting result either way, bit low on the power but then thats due to AFR's to tidy up and a look see will be interesting

yea im very excited as to what it'll do tomorrow...yea afr's need tiding up big time, youll see by the chart im taking a photo of at the moment.

R31nismoid, yea i was skeptical of boost building also, this thing even sounds like an animal coming on boost.

The motor is in a plain jane White STOCK R31 silhouette with stock springs, stock wheels LOL.

keeping in mind timing hasn't been played with yet...this is just power runs to slowly level out AFR's.

Cam's haven't been played with either...Exhaust cam was retarded 5 degrees to compensate for no more CAS adjustment for 15 degrees timing.

I will get an engine bay pic tomorrow and the car itself, youll laugh!

post-23597-1205918570_thumb.jpg

post-23597-1205918617_thumb.jpg

shit... its 6800RPM before its doing much more than one with a RB25 turbo would at about 4500rpm - go the RB20 and the 1.06 :P

Thats love.

I think you might get 300-500rpm on it... but that would be about it.

I wouldnt call boost building from 4500rpm though (more like it makes 2psi @ 5000rpm), and then takes 2000rpm to make the other 12psi hehe

Obviously you boys are doing this for shits and giggles? Wind the RB20 out a bit more, they take 7500rpm ok

yea its for shits...mainly for teaching ourself how to fine tune....

that chart isn't a good indication of boost curve..it was running off a 14psi actuator so once a bleeder is fitted it should kinda spool a tad quicker, also taking some fuel out of the low rpm will help spool just that tad more lol..need all the spool we can get..

Once its all said and done ill put the 2540 on my 25 and put my turbo (gt2871r 56t) on the 20..

ill try find a chart of a better boost curve.

updates!!!!

YESTERDAY: Took a shit load of fuel out, played with the ignition timing as we were going, gradually gaining 10rwkw, ended up with 291rwkw on 16psi!!!!!

MADAZ (steve) took some footage! so that'll be on UTUBE soon!!

Very impressed with the numbers however at the last minute we suspect the exhaust cam is a tooth out as with the stock cams the power came on alot earlier....Will keep you posted with more information

cubes, only specs on the cams i know is 264 duration and .64 something. thats all i can remember offhand..cost a bucket!

here are some pics!

post-23597-1206059116_thumb.jpg

post-23597-1206059237_thumb.jpg

post-23597-1206059282_thumb.jpg

Edited by Ryanrb25

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