130 replies to this topic

[zebwach]

Just got back from manchester from having some un-final, final mapping done. As usual, things didnt go well for me! The following issues occurd. Boost creep. The waste gate is not big enough and requires machining so that it can bye pass the boost faster. Im slightly upset by this as i payed top dolar for it from CMS and it was advertised to beable to run 420bhp with a tubular manifold. Unless my it is a faulty one, i fail to see how they achieve this when it is creeping boost at a meager 340ish bhp at 5.5k rpm. Fuel duty cycle. The vxr injectors are maxing out at 6k rpm and 345bhp at 6k using a 3.2 bar fuel regulator. Chris did the maths before hand and confirmed the max for the vxr injectors at 3bar is 330bhp. So its either some 550's and/or a higher pressure fuel regulator. Mild misfire at 5.5k. This was suspected to be the plugs at the time, but during the drive home this got alot worse. Having had many coil packs fail before, i shall be ordering a new one of those tomorow! I was very impressed that that chris could up the current to the injectors to over come the misfire in the short term. He showed me alot what you can do with it and im very impressed to say the least. Unfortunatly once a pack starts to go, it only gets worse. Anyone know of any uprated coil pack options? Despite all these hurdles thrown at him, he has produced a silky smooth power curve. Max torque is 374 pounds foot held pretty much across the baurd and 345bhp made at 5k. Due to the ignition,fueling and boost creep problems the power was capt at this point to the rev limit of 6k. The creep at that point becomes uncontrolable. Several maps were made ranging from max power carnage, to very gradual power delivery for a start with no torque spike as the turbo spools up. I can switch between them or adjust them in minutes thanks to the software. I realy cant believe how fast it is. Truely scary and ridiculous. But most of all controlable. I have missed out a hole chapter there about how Dave,based in shepshed, even made it possible for me to go for mapping tonight. As well as playing a major role in producing the new equal diameter intake kit, he shall be machining the turbo (if it isnt returnd to cms), and fabricating some new heatshields to fit around the garret. My sound deadening has taken a beating recently! It realy is road runner comicly fast! Of to bed now. Its a shame we couldnt discover its full potential with the standalone management and new intake kit, but i am still blown away with the current results. So much usable power its mind bending. After we backed the initial boost spike back to make it smoother and give the tyres a chance, it is still making 330 torques at 3.2k rpm and it builds up gradualy to this point. Im chatting deleriously and in a non constructive manor now due to my sleep deprevation! I realy am going to bed now!

[Duncan VXR]

Great progress and massive thanks to Dave for helping you out, I just did not have any time free saturday :-( Zac drop the cack oe coil pack and go wasted spark setup. Be about same cost and prob better for you and appitite for coil packs :-S Great torque across the range DG

[zebwach]

Great progress and massive thanks to Dave for helping you out, I just did not have any time free saturday :-(

Zac drop the cack oe coil pack and go wasted spark setup. Be about same cost and prob better for you and appitite for coil packs :-S

Great torque across the range

DG

Iv never heard of this before. Is it something i can fit as easily as a new coild pack and not need more mapping? Well at least, could i map it myself?

[zebwach]

Just been quoted £187 inc vat from local dealer and £97 delivered from autovaux. Iv come to the conclusion that vauxhall are a load of thieving gypsy's and that autovaux sit on the tops of christmas trees during the festive season.

[zebwach]

The decision has been made. Im going for an wasted spark setup with HT leads. Costs are similar to an OEM coilpack but comes with honda levels of reliability. It wont look as neat and tidy with leads sticking out of the head though. Im not sure how the water sealing will work though. Unfortunatly no more progress will be made for at least a couple of months as im flat out broke and need to let the the bank balance recover! I might try some scrap yards to get a better OEM pack for the short term and turn the current down a little.

[Duncan VXR]

Zac will catch up later, they dont need to stick out and there are ones that come out at 90deg so the oe cover fits still. I may be able to loan you a new wasted spark kit if needed but sure I get the oe coil packs from autovuax for a chunk less than that on super trade account if required. In fact have a spare working coilpack in the garage somewhere DG

[Nev]

Bloody hell Zach, 345 BHP at just 5000 RPM is epic. Most GT28s don't start running out of puff until around 6250 to 6700 revs (spec dependent), so you will get quite a bit more power yet which will really help keep you accelerating hard in the 3 figure MPH zone. If you think that you are currently doing 'road runner' speeds, wait till you go over the 400 BHP mark (or further still)! Excellent to see you getting a good result at last. Is the penny washer the standard sized on for the 5 bolt turbo exit? Those things are tiny if it is and no surprise to me that it can't waste the boost fast enough.Maybe someone can drill the wastegate hole wider and weld a new larger penny washer on for you. That should work in theory, but clearly will void your warantee... Well done to you and all concerned.

Edited by Nev, 12 March 2012 - 12:43 PM.

[zebwach]

Duncan. Im very much looking forward to that chat! Cheers nev. yes, it does look promising. Gt2871 rings a bell. So why is it equiped with such a puney wastegate when it is clearly not fit for purpose? I doubt very much the final number shall begin with a 4! Feeling the difference an extra 50bhp and wider power band has made, i dont think my pants could take much more! Besides, i dont want to push my luck with the paddle clutch and fuel pump too much. Smoothness and driveabilty on the road are prioritised above anything else in this instance. Oh yeah, reliability also! That one isnt going briliantly so far!

[Duncan VXR]

one option is to machine the wastegate bigger but within what the penny covers DG

[Nev]

What's your peak torque? If you leave the mapping so that torque remains the same (so the clutch can cope) the power should keep going up so long as the turbo doent run out of puff. Can you post up a pic of the dyno plot please ?

[zebwach]

The peak torque was 373 made at 4.5k - 5k ish. Although we were artificialy reducing it before this so that the power came in gradualy and not in the space of a few hundred rpm. I didnt bother with a graph as it hasnt been finished and will have to be mapped again once all the little niggles have been ironed out.