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I wasn't talking about the v8s torque curve, I was talking about people back then knew that larger duration cams will cause peak power to arrive later in the rev range, the same will happen with a modern import and it doesn't matter if you jump up and down, squeal, pray, beg. that's what's gonna happen

You guys talk as if it takes 5 mins for -5s to spool up well it doesnt, and for those 2 corners on a track where this scenario happens your right but for the the rest of the track a stock gtr will get slaughtered everything else being equal.

About the revving i was just saying, but change gears at 7k and -5 will still be on song.

Changing gears at 8k is not the issue, its when you hold it there around corners things go pop.

I think the Group A cars were limited to 7k as part of the regulations to give the V8s a chance....correct me if I am wrong.

off

The 7k limit was to reduce excessive engine wear

I track both my stock cam stock turbo R32 GTR and my -7 type R poncam R34 GTR, the 34 has better tyres suspension and brakes and making 60 rwkw more and with the extra lag it's just under 2 secs slower around Wakefield, can only imagine how bad it would be if the boost came on a 4k

During 1992 the R32 was ballasted to increase the homologated race weight, and max boost was reduced, enforced by a CAMS/FIA relief valve fitted to the plenum. Bit of a precursor to today's performance parity measures.

Got a chance to talk to Fred Gibson a few weeks ago, he said they ran them up to 8500rpm. They were making 680bhp. Dont know where the 7k thing came from.

That's interesting, I'll have to remember where I heard that, I've based my builds off it so I don't have to run past 7-7.5rpm

I'm sure it was when I was helping the BSM guys

There were a few other things they did after the weight was increased and boost level limited . I will ask but I think one was increasing the static CR but can't remember the other . They didn't get all the power back but enough to reduce the loss .

A .

The 7k limit was to reduce excessive engine wear

I track both my stock cam stock turbo R32 GTR and my -7 type R poncam R34 GTR, the 34 has better tyres suspension and brakes and making 60 rwkw more and with the extra lag it's just under 2 secs slower around Wakefield, can only imagine how bad it would be if the boost came on a 4k

Is that the same scenario at higher speed tracks

They tuned the engine with pressure transducers to do cylinder pressure over crank degrees. On 1.3 bar they went from 550 back to 670bhp. They nearly got it all back.

Very clever stuff.

They tuned the engine with pressure transducers to do cylinder pressure over crank degrees. On 1.3 bar they went from 550 back to 670bhp. They nearly got it all back.

Very clever stuff.

Didn't they use that weight penalty to improve their suspension and chasis too?

I never got a clean run at EC in the 34, but the 34 was 9 secs off the 32 with what it did get

The most time is lost through corners, better exit speed/acceleration means more/higher speed you have along the straight

9 secs a lap slower!! Something else must be going on there. Can't believe a -5 cammed GTR with better suspension and tyres is going to be that far behind. How can this be??

9 secs a lap slower!! Something else must be going on there. Can't believe a -5 cammed GTR with better suspension and tyres is going to be that far behind. How can this be??

It's not, it's -7.

9 secs a lap slower!! Something else must be going on there. Can't believe a -5 cammed GTR with better suspension and tyres is going to be that far behind. How can this be??

Like I said I never got a clear lap in the 34, the 32 on the other hand I got EC to myself for a whole day and lots of lapping was involved as well as two tank fulls

The 32 is just a bulldog of a car with instant useable boost any where over 2000rpm and no down time in boost between gears, a prime example of what happens we you get a mix of parts that work together

Even the fastest track has a few tight corners, EC it's 2-9-11, with 4-5-6/7 slowing you down, all of which show lag for what it is

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