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Even 272s are to long in duration for good low end response, 2.6 with -5s and 98 are never going to be very responsive, start with play around with cam timing, I had type B poncams with -7s and was having the same issue, third to tall second to short, changed the cams to type Rs and then I could drive third out, a responsive setup/motor works on any track

With the kind of power this combo can/should make changing back to 4.3 diff ratios will only result in fighting for traction and mean you'll end up wrestling the car all the way around the track and changing gear twice as much

omg, OP never once stated getting a bigger engine was an option, oh and the RB26 has to be one of the best know motors for track use for it's mid to top end power, reliability and revs.

I agree with Jim and changing the diffs, and the other guys in swapping the cams, and finally making sure it has good soft tyres for grip to enter the corners fast as poss. That will make a big difference to response

omg,OP never once stated getting a bigger engine wasNT an option

plenty of stroker RB28s and RB30s getting around for better bottom end response, thats why plenty of ppl do it

yes they do it for low end torque mostly for street and drag, however the RB26 platform is better for trackwork and hence why Mines' stuck to the original configuration.

But if u were talking VR38 than that's superior in most areas and certainly bottom end torque

Just to play devil's advocate here, I have 1 bar of boost at 4300 rpm in 4th gear. I run a 2.6L rb26 with Tomei 280/10.8 cams and -5 turbos on BP98. I'm not sure why you guys are saying these cams and turbos are a poor match.

That's pretty late for one bar, what power did you end up making? At the end of the day if you are happy with the lag, go for it. The top end should be awesome.

Most guys stop leaning on their setup once the power climbs which means they would be better off with smaller turbo's running harder. I feel the 200kw by 4k rule to be fairly accurate, and gives a good indication of how the car responds.

As above 200rwhp at 4000rpm is a good indicator of response.

If I remember correctly Poncam B's wont do it - the A's are better the difference being limited to a shorter duration exhaust. Also the choice is not just R, A or B Tomei will grind you plenty of other options.

  • 2 weeks later...

So as an indication what lap times are you doing at Sandown? Assuming you have desent semi slicks than if the car is doing sub 1:20s then I say you may be in the region that its time to chase reponse.

Eg on sandown in the tight section it feels like I should be cornering in third but find that to get good power down out of the corner I need to be in second. Second I need to rev the car to 9+g and third is a bit sluggish out.

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