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Being limited by injectors I'm aiming for 230 but have cams and gears so will try and dial it in at the lowest possible rev

I've spent couple of hours on a bridged twin actuator setup with some scraps I had. In theory once both actuators gets connected to a single boost source, the valve open pressure stays the same as having a single actuator, how ever the strength acting against the gate doubles. I hope I'm on the right track and my innovation holding boost steady through out the whole rev range.

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Nice work Stao! Thats effectively the same theory as a 'big can' actuator. Hopefully the extra mechanical load works towards holding higher boost levels flat.

FYI to all readers: Payment for my SS1PU has been made! Can't wait to have my new turbo in my hands!

Its different to a big can actuator, I've used it while ago and I couldn't get rid of the boost drop, the current high pressure actuators worked better.

Big can or high pressure actuators will only work to certain extend, the stronger the actuation spring is the more boost spike occurance in mid range as exhaust manifold pressure at that point is not as high as what they are in upper rev range.

The Actuator is acting against both inlet manifold pressure and exhaust manifold pressure, The EBC can bleed off inlet manifold pressure how ever has no control over exhaust manifold pressure. Pressure at any points of its distribution remains constant, So in this setup the advantage of having two actuators halves the force generated through exhaust pressure.

The end result in theory should half the amount of boost drop or better. I've taken the car out for a thrash with both actuators hooked up in one boost source, they are now sitting at 18psi instead of 16psi on a single. So hopefully it holds 20psi flat on the factory exhaust manifold.

And who said you cant reinvent the wheel? ;)

If you get a chance please take some pics when building my turbo, for my personal build log :)

Car going on a local dyno just to compare boost plots with exhaust on and off tomorrow morning

Talked to head company who modified it. They said although squish pads were removed, de shrouding valves should be helping increase velocity and not create any lag and was advised to get an adjustable exhaust gear, dial cams in and see if it picks up earlier plus should be a bit more Det resistant now than before

Also found in another thread someone say they installed poncams and went backwards because head and block were skimmed so 0degrees wasn't really 0. Will bring a dial gauge home from work after my holiday

Edited by t_revz

im also worried about dialing cams im with the decking... Ive decked my block and dropping off my head to be decked today also. Running poncam type R's I hope it doesnt cause headaches..

My squish pads are removed plus other material in chamber yet after being skimmed previously then this time it's back to original CC so I guess it's been skimmed substantially all up, whereas the block only got trimmed 4"thou.

Tuner cringed this morning when I told him valve guides had been done... he said he'll see how the car goes on the dyno and push it as far as he's comfortable, but he said with the motor having been apart, and given its still on the stock exhaust manifold, he thinks it will be between 350-380rwhp.

Shall see how it goes!

LOL please dont tell us it pulls hard again until it is tuned.

last guy to get a HG turbo and see how hard it pulls, pre tune, blew his motor.

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