My RB30 Precision 6262 dyno

[ST240]

Why does the DE head make the difference? Intake/exhaust ports and valves are a lot smaller than the 25DET and 26. I've heard the cams are "good" but a common upgrade is reground RB26 cams.

[Speeddm]

All my mates who build 30s in NZ use the NA head because it flows more then the 25det head. Nearly the same as the 26. Maybe Im wrong. Ill double check my build notes.

[ST240]

Cool man this is good discussion . I DO recognize the fact that a lot of auzzies post up some real amazing numbers ie 450+ whp with the stock 25DE head.

And again, one of the main reasons I'm doing it is to get the forward facing plenum lol.

[Black BNR32]

I have a bunch of extra 26 head internal parts, plus all the intake side parts, if you need.

[r33_gtst]

I have many mate in NZ that run this combo in their cars and make 500whp+ on stock 30/25de combos and run the $hit drifting and driving daily.

Also, a lot of the guys on SAU say if you're running close to stock bottom end, keep figures around 300 rwkw (400 whp) to be SAFE. That doesn't mean I won't try to push it .

Easily you can push it
My tuner stopped at 492 rwhp 364 lbft @ 20 psi. Said he felt comfortable, could take it to 525 rwhp but running an oem oil pump. You can easily achieve my numbers and pass them. Turn up the boost, get a good tune and your #'s will be bad ass

[Speeddm]

Sorry looked at my notes and called Pete up just to be sure. The DE head works well but it has higher compression so the quench pads need to be removed to make big power.
Sorry to much **** in my head some times.

As for power though. as Soichi would say "Crank Bitchup!" The stock 30 will take it.

[Super_Dude]

Just needs a bigger turbine housing. I wouldnt push it to much with a stock bottom end and a tiny rear housing. If you can monitor egt's and/or exhaust manifold pressure I would love to see what the little housing is doing.

[ST240]

I have been monitoring them and they dont go over 900 in full boost. The guys on SAU said that was still too hot though lol.

The problem with these god damn turbos is the housings are almost half the price of the turbos themselves, so I might as well try another turbo that is better suited rather than buying a larger housing.

A guy locally has a BB 6765 .86 T4 for sale, I may try that or the BW s300sx 83-75. Unless anyone else has a good T4 for sale .

[Dragon Humper]

Yikes man, 900 deg. is WAY to high with cast pistons. Pig rich and that much ex. temp is really slapping you in the face with a 2x4 that your turbine is WAY too small. It's really curious that your boost isn't fully in untill about 4200rpm, only about 500 before me. You would think a larger engine with a tiny (compared to me) turbine would be in over 2000rpm before me. You tune may have something to do with it but I can't see it dropping by more than 300rpm.

Get a good snail on there with the 26 head and you should tickle the 550 rwhp mark at
7000rpm.



Jon.

[ST240]

Yikes man, 900 deg. is WAY to high with cast pistons. Pig rich and that much ex. temp is really slapping you in the face with a 2x4 that your turbine is WAY too small. It's really curious that your boost isn't fully in untill about 4200rpm, only about 500 before me. You would think a larger engine with a tiny (compared to me) turbine would be in over 2000rpm before me. You tune may have something to do with it but I can't see it dropping by more than 300rpm.

Get a good snail on there with the 26 head and you should tickle the 550 rwhp mark at
7000rpm.



Jon.

Thanks for the post. Yeah I've read that a very poorly sized turbine housing that is too small can actually hurt spool. I'm going to try the divided .84 on the 6262 and if that doesnt work, it's gone. Anyways I'll have the head off this winter to see if those egts have done any damage :x.