Jump to content
SAU Community

Recommended Posts

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.

IMAG0971.jpg

IMAG0972.jpg

IMAG0973.jpg

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.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Everyone is too used to learning from places like HPA "how to tune" and what to expect at what point, rather than being able to see "The computer says I'm in cell with Row = 8, column =4, and I can see my fuel is lean, so lets add more" Everyone wants "real units", which helps for someone picking it up for the first time and seeing how bad the tune is if they're not used to touching it.   However, I think for most of us who want to play with it, you're 100% right, we're only needing to learn about it for OUR CAR. Which makes it great, and we don't need to care what the real values are, we just need to know which cell it is, that's causing the lean or rich point, or that we want more ignition timing or less. But again, everyone wants everything super you beaut and nearly self tuning, with VE maps, and a billion compensations...   Though then there's me over here when I'm doing reverse engineering work just reading data in hex format that most people couldn't work anything out from. Yet I can see what's going on.
    • Um. No. Since Matt introduced the TIM it has become a lot easier to deal with the consequences of changing K for AFM and injector swaps. Then, tuning is a f**king doddle. No-one needs to know or care how many grams of air are flowing or any other bullshit. Need more fuel in a cell? Add more fuel. Need more timing in a cell. Add more timing. Need to adjust any of the other tables for warm up and so on? No harder than anything else. Sure - it's not an ECU system for starting from scratch on an arbitrary engine. But then.....it was never supposed to be, not recommended for, and almost never used that way. So.... On your engine, in particular, Nistune/Nissan OEM is about as sophisticated and difficult as banging 2 rocks together. Those ECUs are primitive and simple. There is nothing difficult there. I learnt Nistune from scratch, created new maps with extended axes, interpolated/extrapolated the original maps onto them and tuned my RB20 (basically the same ECU as your 26 ECU) all by myself, more than 20 years ago. And that was long before even TIM.
×
×
  • Create New...