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Looks good dude, but with some more work on the V-cam map I recon it will coulp be up on boost even earlier.
 

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Are you sure the V cam is working correctly? From the dyno plot, it looks like the torque is dropping off really quickly after the torque peak at ~5k. The V cam should extend the torque plateau, not make it peakier.

Perhaps boost dropping off due to exhaust restrictions?
 

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Well done on a great result.

Right now I am also weighing up V Cam with what would also be stock internals at this point; awaiting my workshops response in terms of what outcome is to be expect if dollars are outlayed and whether this is a solution to add now or later. (BNR34 RB26DETT)

Do you have a graph with V Cam off, to understand the gain when its on. All graphs displayed, bar the HKS one, always only seem to be supplied with V-Cam on, but the OFF vs ON would give a true, clearer comparison on the extra power/response yielded and therefore the justification?

What supporting mods do you have to get this result?

The relative performance additions I would have after the operation is:
GT2860-5's (18/19PSI setting due to stock internals)
Nismo AFMs
700 CC injector
HKS Cam Gears
3.5" exhaust system
Greddy race radiator
Replacement intercooler hoses
Custom oil cooler

+ possibly V Cam & suitable Camshafts?

Is this the HKS V Cam Step 1 Type A?

Cheers

Ben
 
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I think I have a dyno plot of a car with V-cam run with static value,s in the cam map from 9o to 120 degreein 10 degree intervals , to see what works and doesn't. I showed how well the kit worked , will go and have a sort out today while on the dyno.
 

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Yeah fair call with the updated tuning required in off mode; ordinarily wouldnt expect anyone to invest the extra coin to tune in that mode coz who in their right mind would want the Vcam set as OFF once its been installed and tuned.

Yeah based on HKS graphs and others I have viewed they all look certainly impressive and I would be very happy to achieve your results at 19PSI.

R u running a 3" or 3.5" exhaust system?

Also, you didnt mention whether you are running Step 1 Type A, or Type B? If I move ahead with it I would be running Type A due to standard pistons.

Your mods would almost be identifical to those I have except your running the HKS 2530's and I'd be running the Garret 2860 -5's; comparitive turbos but obviously most rate the 2530's better if you willing to put in the extra coin. Not sure if you have had experience with both?

Is 24PSI ok with fairly stock internals? Seems somewhat high - unless this is just an occassional squirt and not an every day setting - also pending on the length of engine life you are also content with lol! 6months, 12 months, 24months etc. ;)


No vcam on vs off graph, I guess because to get the most out of "vcam off" you also have to make a new tune for that situation. Otherwise it isn't fair.

But from what I can dig up online HKS say there is a shed load torque at low to mid range, and somewhat more at the high end. I suppose more torque means more exhaust volume which then in turn means a slightly earlier spool too. You can see the graph I hot-linked to.. the dotted line is "off".

I listed the mods. I forgot a few. Induction improvements (pods inside a stock looking airbox). Oil cooler. Nismo radiator and thermostat. Hard pipe kit. Nismo timing belt. HKS cam gear on the exhaust cam. 780ps clutch. Stoptech brake kit. Chassis bracing. Coilpacks. Hotter plugs. Fuel rail. Metal gasket.
 

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I think I have a dyno plot of a car with V-cam run with static value,s in the cam map from 9o to 120 degreein 10 degree intervals , to see what works and doesn't. I showed how well the kit worked , will go and have a sort out today while on the dyno.
Abbey it would be great to see any additional information/results from your testings!

Cheers

Ben
 
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V_cam experiment

Attached is a dyno plot from a RB fitted with a Step B kit , running static value from 100 to 125 degree's cam timing.

Think it shows what the V-cam can do very well. Car was only running 0.8 bar boost , base map to check V-cam benefits , once we had and idea on the cam angles we built a V-cam map.
 

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Attached is a dyno plot from a RB fitted with a Step B kit , running static value from 100 to 125 degree's cam timing.

Think it shows what the V-cam can do very well. Car was only running 0.8 bar boost , base map to check V-cam benefits , once we had and idea on the cam angles we built a V-cam map.
hum it's interesting

can you tell us what curve is with what timing please?

it seems there's important gains @ lower rpm's
 
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to get car up on boost earlier you need to open the cam early agaisnt crank postion.

The dyno plot curves are from 100 to 125 degree before TDC
 
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