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

    • Update 3: Hi all It's been a while. Quite a lot of things happened in the meantime, among other things the car is (almost) back together and ready to be started again. Things that I fixed or changed: Full turbo removal, fitting back the OEM turbo oil hardlines. Had to do quite a bit of research and parts shopping to get every last piece that I need and make it work with the GT2860 turbos, but it does work and is not hard to do. Proves that the previous owner(s) just did not want to. While I was there I set the preload for the wastegates to 0,9bar to hopefully make it easier for the tuner to hit the 370hp I need for the legal inspections that will follow later on. Boost can always go up if necessary. Fitted a AN10 line from the catch can to the intake hose to make the catchcan and hopefully the cam covers a slight vacuum to have less restrictive oil returns from the head and not have mud build up as harshly in the lines and catch can. Removed the entire front interior just shy of the dashboard itself to clean up some of the absolutely horrendous wiring, (hopefully) fix the bumpy tacho and put in LED bulbs while I was there. Also put in bulbs where there was none before, like the airbag one. I also used that chance to remove the LED rpm gauge on the steering column, which was also wired in absolute horror show fashion. Moved the 4in1 Prosport gauge from sitting in front of the OEM oil pressure gauge to the center console vents, I used a 3D printed vent piece to hold that gauge there. The HKB steering wheel boss was likely on incorrectly as I sometimes noticed the indicator reset being uneven for left vs. right. In the meantime also installed an airbag delete resistor, as one should. Installed Cube Speed premium short shifter. Feels pretty nice, hope it'll work great too when I actually get to drive. Also put on a fancy Dragon Ball shift knob, cause why not. My buddy was kind enough to weld the rust hole in the back, it was basically rusted through in the lowermost corner of the passenger side trunk area where the wheel arch, trunk panel and rear quarter all meet. Obviously there is still a lot of crustiness in various areas but as long as it's not rusted out I'll just treat and isolate the corrosion and pretend it's not there. Also had to put down a new ground wire for the rear subframe as the original one was BARELY there. Probably a bit controversial depending on who you ask about this... but I ended up just covering the crack in the side of the engine block, the one above the oil feed, with JB Weld. I used a generous amount and roughed up the whole area with a Dremel before, so I hope this will hold the coolant where it should be for the foreseeable future. Did a cam cover gasket job as the half moons were a bit leaky, and there too one could see the people who worked on this car before me were absolute tools. The same half moons were probably used like 3 times without even cleaning the old RTV off. Dremeled out the inside of the flange where the turbine housing mates onto the exhaust manifolds so the diameter matches, as the OEM exhaust manifolds are even narrower than the turbine housings as we all know. Even if this doesn't do much, I had them out anyways, so can't harm. Ideally one would port-match both the turbo and the manifold to the gasket size but I really didn't feel up to disassembling the turbine housings. Wrapped turbo outlet dumps in heat wrap band. Will do the frontpipe again as well as now the oil leak which promted me to tear apart half the engine in the first place is hopefully fixed. Fitted an ATI super damper to get rid of the worn old harmonic balancer. Surely one of the easiest and most worth to do mods. But torquing that ARP bolt to spec was a bitch without being able to lock the flywheel. Did some minor adjustments in the ECU tables to change some things I didn't like, like the launch control that was ALWAYS active. Treated rusty spots and surface corrosion on places I could get to and on many spots under the car, not pretty or ideal but good enough for now. Removed the N1 rear spats and the carbon surrounding for the tailpipe to put them back on with new adhesive as the old one was lifting in many spots, not pretty. Took out the passenger rear lamp housing... what do you know. Amateur work screwed me again here as they were glued in hard and removing it took a lot of force, so I broke one of the housing bolts off. And when removing the adhesive from the chassis the paint came right off too. Thankfully all the damaged area won't be visible later, but whoever did the very limited bodywork on this car needs to have their limbs chopped off piece by piece.   Quite a list if I do say so myself, but a lot of time was spent just discovering new shit that is wrong with the car and finding a solution or parts to fix it. My last problem that I now have the headache of dealing with is that the exhaust studs on the turbo outlets are M10x1.25 threaded, but the previous owner already put on regular M10 nuts so the threads are... weird. I only found this out the hard way. So now I will just try if I can in any way fit the front pipe regardless, if not I'll have to redo the studs with the turbos installed. Lesson learned for the future: Redo ALL studs you put your hands on, especially if they are old and the previous owners were inept maniacs. Thanks for reading if you did, will update when the engine runs again. Hope nothing breaks or leaks and I can do a test drive.
    • No those pads are DBA too  but they have colors too. I look at the and imo the green "street" are the best.
    • I’m not sure what happened I told them about sonic tunes free OTS tune and the next the I know .. I was booted..   To funny 
    • Yea - I mean I've seen my fuel pump which is decades old and uh, while I'm not saying this with real knowledge... but I sure get the ick at using anything in the fuel system that produced the state of that pump. Many years ago I went through multiple pumps (and strainers) before I dropped the tank to clean it out with extreme violence. I'm talking the car would do maybe 50km before coming to a halt, which resulted in me cleaning out the filter with some brake cleaner and going on my way. None of my stuff ever looked like what came out of your fuel tank. I don't think I'd be happy with it unless every single component was replaced (or at least checked/cleaned/confirmed to be clean here).
    • I'm not going to recommend an EBC pad. I don't like them. Just about anything else would suit me better. I've been using Intima pads for a while now.
×
×
  • Create New...