My RB feels to be more than somewhat lacking around 4000rpm. See attached chart.

It has the following

Garrett 28-60's 707160-5 turbos.

HKS dumps.

Tomei Poncams.

Unadjusted cam gears.

Power FC with Z32 AFM's.

Stock internals with good compression.

Some other random parts which probably aren't very important

Basically my question is this:

How can I get some more torque from 4000rpm to about 5000rpm?

Nitrous

Seriously tho, I would be playing with the cam gears. you may however loose some top end to gain power in the midrange.

its all in the timing and tuning, get some adjustable cam gears....assuming you mean non adjustable cam gears not non adjusted adjustable cam gears. ...(not cheap ones the screws rattle loose),......does that make sense????????????????????

and then go back for a full tune( assuming its a aftermarket ecu/piggyback?)

if not you'll be better off with one of those too.

richard,

just did some dyno time last night and i have the same gear as you but forge internals now.

I have a bit of porting done to the head and manifolds but shouldnt be a million miles away.

with the 260 x 9.15 cams we made 470 hp at 1.35 bar boost and 330 odd ft/pd torque. We then advanced the inlet cam 2 degrees and retarded the exhaust 2 degrees. then made 465 hp but 386 ft/pd torque at 7500 at 1.35 bar.

boosted a bit earlier as well, around 3800 for usable boost pressure.

Worth a try.

richard,

just did some dyno time last night and i have the same gear as you but forge internals now.

I have a bit of porting done to the head and manifolds but shouldnt be a million miles away.

with the 260 x 9.15 cams we made 470 hp at 1.35 bar boost and 330 odd ft/pd torque. We then advanced the inlet cam 2 degrees and retarded the exhaust 2 degrees. then made 465 hp but 386 ft/pd torque at 7500 at 1.35 bar.

boosted a bit earlier as well, around 3800 for usable boost pressure.

Worth a try.

Cheers for that. The motor I have is a bit rediculous. It has bolt ons to run it up over 500rwhp but stock internals, so has been turned down to allow it try & live a troubled life. I got crunched for time for getting the tune done which meant no fiddling of the Tomei cam gears. The joy of living in the bush is RB gurus are 180km away in Perth.

Anyway I would be curious to see what people are generating in terms of rwhp through 4000rpm.

see if i can get the print out for you i didnt bother as it was late when we finished up.