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Very good improvement over the RB30 and you would assume that kind of improvement between a RB30 and a RB26...

Must be a issue some kind of other issue with the car though as boost seems incredibly lazy for a 3.4L with a T04Z, we see similar results from 2.6L :thumbsup:

Edited by SimonR32
You are very naive to think that!

Why?

Every T04Z setup i have seen, whether it is on a RB20 or a 3.4L 2J has always been lazy.

The wheel design hasn't changed since the 1970s Garrett T67, all they have done is add a ball bearing cartridge, and some fancy anti surge holes.

that is really nice! but its an expencive 250rpm gain in response and 35hp

Nice, someone that only looks at the final power figure. :)

3500 its up 50hp 4000 its up about 130hp 4500 it's up about ~70hp. i'll take that any day of the week, would be a massive improvement on the road.

Looking forward to a torque graph!!

I think more head work would help, no doubt with the extra 400cc the ports will need to be bigger.

I doubt sticking a 3.4L bottom end in a car with stock cams and ports will net good results, Would make a good low rpm streeter, but to get the most out of it will require a heavily ported head with very large cams.

I still want to know the rod length and pin height, My guess is the rods are around the 5.8-5.9" mark (maybe standard 25/26 length?), I dont think there is room to raise the pin heights for standard 6" rods and a 9mm stroke increase

that is really nice! but its an expencive 250rpm gain in response and 35hp

Its at least a 350rpm gain in response when I look at it. As said the hp gain is a lot more in the mid range.

Agree about headwork required to get the most out of the extra capacity.

To me the only really negative to a skyline is the lack of low down torque when still demanding good top end power. This is getting closer to having the best of both worlds and a worthy quest in my opinion.

Very good improvement over the RB30 and you would assume that kind of improvement between a RB30 and a RB26...

Must be a issue some kind of other issue with the car though as boost seems incredibly lazy for a 3.4L with a T04Z, we see similar results from 2.6L ;)

Not a chance a 2.6 and t04z (pump) is never even close to that unless its running a bullshit ramp rate.

a genuine 454rwkw and 4000-4400 full boost threshold is a pipe dream for a 2.6 litre, i reckon a tighter gate spring or an adjustment in preload (jap gates have the preload / travel limiter) would have it on full song @ 4000.

i had a T78 with the same curve and we kept winding in the gate pre-load until it ramped to full boost without the slight curve.

Not a chance a 2.6 and t04z is never even close to that unless its running a bullshit ramp rate.

a genuine 454rwkw and 4000-4400 full boost threshold is a pipe dream for a 2.6 litre, i reckon a tighter gate spring or an adjustment in preload (jap gates have the preload / travel limiter) would have it on full song @ 4000.

i had a T78 with the same curve and we kept winding in the gate pre-load until it ramped to full boost without the slight curve.

2 questions about that

1 did it still regulate boost properly ?

2 did this make it come on faster or just make boost come on a different way?

thanks

2 questions about that

1 did it still regulate boost properly ?

2 did this make it come on faster or just make boost come on a different way?

thanks

based on the graph on the previous page i would say it would be worth about 50hp @ 4250rpm.. not bad for free

Not a chance a 2.6 and t04z is never even close to that unless its running a bullshit ramp rate.

a genuine 454rwkw and 4000-4400 full boost threshold is a pipe dream for a 2.6 litre, i reckon a tighter gate spring or an adjustment in preload (jap gates have the preload / travel limiter) would have it on full song @ 4000.

Waits for SimonR32 to reply...

Not a chance a 2.6 and t04z (pump) is never even close to that unless its running a bullshit ramp rate.

a genuine 454rwkw and 4000-4400 full boost threshold is a pipe dream for a 2.6 litre, i reckon a tighter gate spring or an adjustment in preload (jap gates have the preload / travel limiter) would have it on full song @ 4000.

i had a T78 with the same curve and we kept winding in the gate pre-load until it ramped to full boost without the slight curve.

Wait, what?!?

l_b7eca4ab19da63cf98eae41ae9b99bfc.jpg

13065_226473479702_508809702_4240776_6507335_n.jpg

Also have another graph with 467rwkw that overlays the first graph untill it carrys away top end...

I do agree through that a harder boost ramp would be a huge improvement :D

Edited by SimonR32

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