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That's pretty impressive from a 2.1Litre........

Here's a 2L running 28PSI .... power is at the hubs. Comes on a bit later, but holds it's power nicely.... reasonable spread of power too.

 

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From a certain blue evo is it Fraser?
 

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Something close Rob...............that blue evo makes 1158HP at the hubs I think or something close.
 

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Discussion Starter #47
Is he using Nitrous or high compression to spool that gt42 so early on a 2100cc engine? 2.7bar @ 4400rpm!?

I would of thought a 2.1L would start to spool a GT42, at best ,from 5500rpm with 2.7bar peak arriving 6500rpm+

That powerband looks more like what a 3litre with a gt42 should do
No nitrous, compression in the 7's, not like it makes a jot of difference to spoolup rpm.

Its called speccing an engine properly.
 

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Here's one Gary Passingham was playing around with back in June. Early run on new engine, pump fuel, too rich and with a glitch when the secondary injectors came on line.

Doesn't match the Dagenham Dustbin torque figures but OK for 1.7bar road use................... and to take the win at Round 3 PRO Drag Street Series! :thumbsup:




It gets a bit more lively on race fuel and higher boost.
 

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Discussion Starter #50
ATCO- The point was how much midrange it has, ie its driveable, and not even having 250bhp or 250lbft by 5000rpm (under half of each what the YB had by the same revs) doesnt make the graph you posted look very nice on the road to me, esp as that engine has half a litre over the one I posted.
 

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Steve, I didn't offer any comment about driveability and you will get no arguement from me about the benefit of mountains of torque from low revs. I posted it just by way of comparison and to show that whilst you can get BHP, it does not necessarily guarantee torque across the range like the Ford.

The above torque curve admittedly does change substantially when the boost is turned up, however the configuration of the engine is never going to deliver a shed load of torque at low revs. But it does not matter because under 'power' conditions with the sequential gearbox the rev-drop on changes still leaves you above 6000.

With respect to road use, I have commented before about how the car drives. The map has been cleaned up somewhat since this initial run to deliver more, cleaner power/torque, however that sharp thresh hold between asleep and awake remains. It isn't in reality that bad on the road because it means I can drive around in the 1500-4000 range with enough power to clear any traffic without getting any nasty surprises. As you can well imagine only a gnats whisker of throttle at the wrong revs/moment sends the car ballistic. OK, you can argue what's the benefit of driving around 'off boost' it seems somewhat pointless, well the novelty of constantly fighting big horsepower on the road all the time soon wears off, gaps to the vehicle in front are perpetually non-existent, every corner begins to feel 'tight' and the life expectancy of your license can be counted in minutes. It isn't like a bike where you can go for the gap or flick around an obstacle. However, when those rare moments arise when the road is clear and its safe to let the revs rise............ its all worth it!

Get yours together and join the club.
 

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SteveN: that is truly amazing then, the graph for the evo CANMAN posted shows the 2L having its powerband from 6700rpm-9400rpm with a large turbo, so with a 2.1L/GT42 to drop that powerband threashold to 4400rpm with only 100cc more must have had alot of time and effort put into it. M.A.D should start doing RB engines, then we could see big boost from 3500rpm on an RB 26/GT42
 

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SteveN: that is truly amazing then, the graph for the evo CANMAN posted shows the 2L having its powerband from 6700rpm-9400rpm with a large turbo, so with a 2.1L/GT42 to drop that powerband threashold to 4400rpm with only 100cc more must have had alot of time and effort put into it. M.A.D should start doing RB engines, then we could see big boost from 3500rpm on an RB 26/GT42
Mark has! He was the original mapper of Keith Cowies car when he swapped to the Autronic EMS.

I think he is an acknowledged expert with Cossie's, however not all engines are alike so whilst the core knowledge is always valuable the idiosyncrasies (tricks) of particular models (like an RB26) often needs extensive experience of mapping them to draw upon to get the very best out of them.
 

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I would be very interested to know the setup combo and if he's got a dyno graph showing a GT42/t88/t51r [BIG turbo etc] on an RB2.6L [no vcam] but any cam setup and head work, compression 8.5 or less. To see it making serious boost at as low RPM as these cossie engines can manage, it should be even lower RPM with 20% more engine capacity.

All the RB graphs ive seen on a 2.6 show big turbos waking up at over 5000rpm
 

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Keith was originally running twin 3037S units like myself, which Mark did the original mapping.
Since then I think he has moved on (up?) to a GT60, not sure if Mark has done the mapping for it or not.
The car as far as I'm aware has not/never been on a dyno.

If you want to see an uprated RB26 with a T51R maybe Henk/skyrocket will put one of his up. I know he gets (claims!) good spool up and mid-range and his son did win the Dutch Time Attack event at Zandvoort earlier this year in the Car.
 

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cheers ATCO, i will ask henk, i think i may of seen his dyno before, but will have another look to be sure.

nothing i have ever seen compares to this 2.1L cossie on a gt42 with apparently no Nitrous,

2.7bar, GT42, 7:1compression, 2.1L ,all at 4400rpm sounds amazing to me. On an RB26 that should be 3500rpm~ [allowing for 20% more CC]
 

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It's worth noting the results for ROd's engine come from an engine dyno where you can hold the RPM until the boost rises. Unless you hold it on the brakes you're not going to see those torque levels at 4500rpm with normal driving.
 

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It's worth noting the results for ROd's engine come from an engine dyno where you can hold the RPM until the boost rises. Unless you hold it on the brakes you're not going to see those torque levels at 4500rpm with normal driving.
I was thinking there'd have to be something like that going on but didn't want to start anything.

I think it would be a pretty safe bet to say that if he drove along in 4th gear at 4000rpm and nailed it, not alot would happen for quite some time.

Rob
 

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How come all the dyno graghs are curved, expect the 2l engine one?

Was it drawn with a rule?
 
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