Tune up of my old motor/blower combo in my brothers VE Commodore, running a TR6060 Gearbox with a 3.27 ratio diff for Racewars 2017. Boost drops from 5400rpm (max is 14psi), but with 640rwhp @ 4800rpm she’s a monster!

Should have updated this one a few weeks ago, so I’ll just do the one big update to bring you up to date on how the car is going.

After the initial re-tune after purchase I took the car down to the motorplex on the 20″ street tyres, best et for the night was an 11.029 @ 205.54kph. Most of the launches were done with 2nd gear to prevent wheel spin, so 60 foot times were nothing to write home about.

A week or 2 after racing the car on the street tyres, I put on my Racestar drag rims/slicks and took it out for another night of racing.

With the slicks on, the car ran 10 second passes consistently. Except the car was badly hesitant off the line on the launches which i knew was because of fluid rushing to the back of the transmission pan.

In the end i got about 5 runs all up with the best being a 10.713 @ 208kph. In the below video you can hear the hesitation just before the 1st shift into 2nd gear.

The following week I took the ute back down, this time with an additional 2 litres of fluid in the transmission and my 4 piston brembo’s on the front of the car (mainly to help with holding the car on the line when stalling up and because stock ve brakes are shit).

This dropped the car’s et by .200 of a second and made it do consistant 1.5 – 60″ footers and run a new pb of 10.57 seconds.

So that’s it for the 1st big update, the car is now back on it’s 20’s until I upgrade the injectors, add Flex-fuel sensor for running E85 & increasing the boost.

06/07/2016 No More updates on this car, I’ve now sold it as I have another project I want to finish off.

So as mentioned before, I got myself a ve ssv ute loaded with plenty of mods, unfortunately during the previous ownership someone drilled a large 6mm hole in the throttle blade.

Now if your wondering why they did this it’s pretty simple. It was done as a quick fix, laziness or they just didn’t know how to tune the Electronic Throttle & idle control system properly for this camshaft.

The main reason why you would drill a hole in the blade of any car is it effectively allows more air straight into the manifold when the factory bypass won’t flow enough air, or the blade is movement limited.

Now that’s okay to do on the cable operated throttle bodies & even on some very large camshafts you will have no choice but to drill a hole even on a ETC controlled motor, BUT in this case for this particular engine combo it was not required at all. As you often end up creating more problems then you attempt to solve such as; exaggerated lumpy idles, cruise control effect when you back off the throttle, hanging idles when coming down through the revs or to a stop.

To give you an example, below is a screenshot log of my car in-gear with the original idle tune and 6mm hole throttle body from above. (Click to enlarge)

As can be seen in the log there are 2 things that stand out:
1) Large swing in timing & idle rpm
2) High manifold vacuum which leads to poor braking

This is because the ecu is commanding a set idle speed and is than constantly over-shooting then under-shooting it. To fix this the ecu can do 2 things, adjust the timing (reacts quicker) or adjust the tb position (slower reacting) to meet the requested idle speed.

I won’t go into the technical details on how this is fixed, because to most people it wont mean anything but needless to say once a throttle blade with no hole and the idle parameters are setup correctly, the idle ends up being a lot smoother without the excessively noticeable camshaft lope and more vacuum for braking. The results would be the same even with a hole, but only if your tuner has calibrated the relevant tables to compensate for the additional airflow.