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Keith C
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Had the car RR'd today. Graph was 284bhp@wheels, which after the atmospheric re-correction (apparently the software automatically 'corrected' down because it was so cold), so the *actual* number going down to the wheels was 306bhp. Last RR I did was 315whp with the same mods, so nice and consistent :)

 

Not bad, only mods are a full decat and a bleed valve.

 

Best bit is that there's plenty of fuelling - if anything, it's too rich at the top end!

 

I'll get the graphs up at some point.

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It was on Surrey Rolling Road

 

Peak boost is about 1.2 bar just after the transition, but as it's only a bleed valve it then drops until it's a little under a bar by redline.

 

Peak torque was about 315lbft at the wheels @ about 4800rpm, but again due to the boost drop was down to about 230lbft at the wheels by 6500rpm.

 

Fuelling seemed ok, although a second opinion would be great. At 1600rpm it was at 13.1, immediately before the transition it was 12.5 before dropping to 11.0 at 4000rpm, down to 10.5 at 4200, back up to 11.3 at 4500 with a then very linear drop off down to 10.0 by 6500rpm.

 

This is the graph from a RR day taken a few years back. Car is unchanged mod-wise except for a CW SMIC fitted a couple of summers ago, and maybe a fraction less boost (I turned the bleed valve down one winter to put a stop to the 1.5 bar peaks I saw a couple of times!). The graphs I have today look very similar, although the ones from today are smoother above 4500 (less 'jittery') and don't have that odd peak at 6500. Can't get those up until I can use the scanner at work tomorrow.

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  • 4 weeks later...

All looks good. Nice respectable power figures there.

You could probably gain another 20 hp by leaning it off to a more 'normal' level! - Still, better rich than lean.

All the UK's I've seen overfuel by quite a lot. Way beyond the point of safety. Still can't figure out why Toyota put 550's in... (No, I'm not saying it's a bad thing... Well, depends how you look at it ;) )

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You can stick an AFC or an E-Manage on there and trim the airflow back a bit. Running above 1 bar of boost = 100% duty on a J-spec, no idea re the UK spec though. That explains the mad richness if you've got 550cc injectors, and the increase in 'fuelling' is possibly a decrease in turbo efficiency at the high end of the rev range - same amount of fuel going in but less air to burn with it, therefore a richer and richer condition occurs... Something Tony spotted with his AEM.

 

-Ian

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