MY04 Liberty GT - FrankenStien - EOI welcome / FS

[dr20t]

All good mate wasnt suggesting I need you to look at it

Have pretty much optimised the tables myself - just curious on the theory you apply with dual avcs for spool as my tables are different to yours now

Mick

[KiDo_Tuning]

All good mate wasnt suggesting I need you to look at it

Have pretty much optimised the tables myself - just curious on the theory you apply with dual avcs for spool as my tables are different to yours now

Mick

I didnt need you to email it, thought you wanted to discusss it.

I will send you the WGDC tables for the 4 port if you want a good start point though

[<GB>]

Im thinking about going to 3 port with mine so I get some of the safety features having the ecu control boost.

I'll await your feed back

[dr20t]

All good mate wasnt suggesting I need you to look at it

Have pretty much optimised the tables myself - just curious on the theory you apply with dual avcs for spool as my tables are different to yours now

Mick

I didnt need you to email it, thought you wanted to discusss it.

I will send you the WGDC tables for the 4 port if you want a good start point though

Thanks man

But what about the avcs?

[dawesy]

Pretty impressive to experience this thing launch spinning all 4.

Also good to catch up again man.

[kiahatsiu]

So Facebook tells me this thing went to the track again last night.
How did the launching go?

[alexeiwoody]

So Facebook tells me this thing went to the track again last night.
How did the launching go?

+100

[dr20t]

Nope couldn't launch. Marshall's were hurrying me up on the line wouldn't let me stall it up. Happened twice so ended up going home after two runs

Gave Dawesy a demo of the boost launch in the car park. It took 8-10 seconds of stalling it up to get to 20psi which I need to find a way to improve in order to get it to launch.

Will be playing with avcs at low load as well as putting that long awaited v band clamp on the uppipe to try eliminate any exhaust leakage.

See how it goes

[kiahatsiu]

I had a theory, but I think it is clearly wrong from what you just said. I was wondering if it was that you cannot get wheelspin on prepped track? On the street, stall it up, it breaks traction and off you go, prepped track, grips and bogs. Obviously not the case if it isn't getting on to boost.
You considered a cheap turbo beanie or something to try and trap some heat in?
I see all these WRX's and what not running 1.6-1.7 60s and I can only manage 2.0 at best. And then it only translates to about 117 mph. You car just storms home up top. In my car's defence, it was 38 degrees last time I went to the strip though.

[dr20t]

Not even getting onto "usable" boost on the brake stall Ian. I can get 3psi instantly as soon as I load it up, and once it gets to 7-8psi boost starts to build alot quicker. But getting to 7/8psi is like 6-7 seconds then another 3-4 seconds to get above 14psi, total about 10 seconds, which they won't let me stall up for.

Also Wsid is almost perfectly flat so no load on the Convertor like it would with a slight incline.

If I can find a way to build boost faster on the line then I will definitely run a low 11 its got the power and torque in it. Like I said I will play with avcs etc to try and do it.

A smart bogan last night suggested I immediately get a 50hp shot into it which will be more than enough to get an instant 14psi on stall. But I'm trying to do this in complete "street" trim.

Mick

[alexeiwoody]

Not even getting onto "usable" boost on the brake stall Ian. I can get 3psi instantly as soon as I load it up, and once it gets to 7-8psi boost starts to build alot quicker. But getting to 7/8psi is like 6-7 seconds then another 3-4 seconds to get above 14psi, total about 10 seconds, which they won't let me stall up for.

Also Wsid is almost perfectly flat so no load on the Convertor like it would with a slight incline.

If I can find a way to build boost faster on the line then I will definitely run a low 11 its got the power and torque in it. Like I said I will play with avcs etc to try and do it.

A smart bogan last night suggested I immediately get a 50hp shot into it which will be more than enough to get an instant 14psi on stall. But I'm trying to do this in complete "street" trim.

Mick

Bummer dude!

I wonder if it's worth changing a street car to suit 1/4, when it's performing better on the street as is?

What speed did it trap at?

[dr20t]

Yeah it is a bummer

Backed off when it wasnt launching so was only trapping 109-111 mph

[peadya100]

He he he... smart Bogan! Love it!
I'm keen to have another go at the drags next month Mick. I'll tee it up for a night you're going.

[Deep Heat]

A smart bogan last night suggested I immediately get a 50hp shot into it which will be more than enough to get an instant 14psi on stall. But I'm trying to do this in complete "street" trim.

Amateurs dont use nitrous oxide. I've seen the way you drive, you've got a heavy foot. You'll blow yourself to pieces.

[dr20t]

A warning in advance - this is a long post as it covers alot.

So I've been doing some extremely thorough digging in my (limited) spare time, and feel I have come to a very important finding which explains a hell of alot.

As many would know, ive been playing with my dual avcs settings in an attempt to improve overall driveability, off-boost response, turbo spool and (least importantly) top end power. Without going into a ridiculous amount of detail which I've covered a million times before, my turbo spool was suffering, even with a 0.63 housing on the gtx3076. In 2nd gear, it would hit boost threshold (1psi) at 2000rpm but not make full boost until 4400rpm. That's a long time and laggy when experienced on the street as a driver or passenger in an auto. In 3rd gear boost threshold was same but full boost at 4000-4200rpm depending on how hot the headers were (ie two or three consecutive pulls in a row would make it spool faster on the third or fourth pull).

This was with the 0.63 housing that I put on around September/ October last year. Was worse with the 0.82 housing.

Above 3500rpm the car was great to drive, but below that in any gear other than first was a dog.

So for a couple of months now I've been working on the tune myself with the 0.63 housing. Optimizing my avcs helped. And I could brake boost to 21 psi and pull four wheel 20metre burnouts when I did it. But it was still taking too long for my liking at 7-10 seconds on the brake. Something still didnt seem right as my engine flows a shit load of air and should not be this laggy with the 0.63 gtx3076.

However once on full boost, this engine is truly amazing. So was Jekyll and Hyde and too far skewed to Jekyll for usable street power being subdued.

Another thing I kept hearing from multiple "experts" on ej207's is my car can't really be making the power it is with stock heads, cams and block. I kept shutting this out as "hate" and also because I knew the v10 ej207 is a freak of a motor. Plus with my cams and heads, i was happy that it was a solid engine and that other ej's weren't as special (bias much)

I tried multiple settings with the avcs and then ignition timing and got it running better. However it was still too laggy from what it theoretically should be and what my gut was instinctively telling me it should be for this setup.

I also found with the 0.63 housing that the top end suffered a little bit from when the 0.82 was on there and from what i liked. So last weekend I switched back to the 0.82 and was determined to getting the cam timing right to get it to spool.

I made the required adjustments to the tune then started optimizing cam timing for the 0.82 housing. The car was definitely laggier again (something I didn't miss) but above 4000rpm the torque is insane. Absolutely insane and pulls all the way to redline very strongly. Which got me thinking. The jump from 0.63 to 0.82 on a 2.0 litre with this turbo should not be as great as it is. If it was a larger turbo that was being restricted by the 0.63 housing then I would understand. But a 2.0litre doesn't choke with a 3076 and 0.63 housing.

Continued to play with cam timing and still not getting spool right as I want it. Alot better than before but still not right. I've done to death the check for exhaust leaks and cracks and heat being retained and everything else bar unicorn fairy dust being misplaced.

So today I embarked on a mission to test a theory out. I set my exhaust avcs advance (yes advance not retard) to something substantial, dropped my ignition timing and added fuel. Low and behold, spool improved but I was getting little torque. So off boost driving was a shit. Played around a little more then had a lightbulb moment.

Pulled timing covers off today (an absolute bitch with engine in car) and checked my static cam timing. Took me a couple of hours to do properly cos my brain wasnt registering and then it clicked. My exhaust cam on the left hand side has been installed retarded 15 degrees, and the right side 12 degrees retarded.

It all now makes sense. The lag, the feeling when running "normal" avcs settings that ignition timing is retarded. The fact that no amount of ignition advance was helping and that my antilag setup wasn't working as it should.

Effectively this means the exhaust valves are opening and closing 15 and 12 degrees of crank rotation later. Meaning overlap is high and causing reversion with normal avcs settings.

This would also explain why my car makes alot more power up top and is a bit of a "light-switch". Retarded exhaust favours top end power, and this further explains why the 0.82 housing made such a difference up top to the 0.63, because the engine breathing characteristics are skewed toward the top end so when a more "restrictive" exhaust housing is presented, and the avcs settings aren't adjusted to suit, then its as if I've released a whole heap of backpressure off the engine.

Thankfully, my avcs adjustment range is -50 to +10 on the exhaust side (50 degrees of retard and 10 degrees of advance). This means with the advance I can effectively remove most of that -15 and -12 of static cam retard with the tune, so no need to remove and reset the cams at this stage thankfully.

Didnt get time to optimise the tune with this new knowledge, but I'm going to also check the intake cams before making a play with it.

Wil keep this thread updated and I'm actually excited to see the difference with the results.

Mick