BGTV8 VQ40HRGA Race engine build

BGTV8

So we have tested the last 2 Fridays.

On the 21st, things did not go so well. We lost an hours and a half finding and fixing an oil leak at the rear of one cam cover. At some stage, it had taken a knock and there was a hairline crack that was rectified with sealant but the biggest problem was blowing a high-pressure fuel pump fuse twice in the afternoon - clearly something was not right and we did not have the time to pull the tank out and inspect to find the issue.

Last week was spend re-doing the fuel system (found a partially blocked pre-filter in the internal fuel pot which was the root cause). We used the standard tank with CJ Motorsport road race system which works a treat by the way, BUT with the cage in place, serviceability is not great - takes an hour to get to the pumps and ~30 minutes to stitch everything back together, so we've gone for a tank above the floor with external lift and high-pressure pumps that are instantly accessible so its is much better for serviceability.

Some lucky Aussie is going to get the CJ Motorsport system in the near future for 50% off.

Last Friday we tested again (3h20m tow to the circuit). The car ran flawlessly - still running the wet-sump engine and R-Spec tyres (6 years old so not very quick) but I did 6 x 25 minute session and it did not miss a beat. The CIRCO pads are brilliant and the 4.08 ratio and Quaife 1:1 top 6-speed sequential works like an old school bolt-action rifle - slight tug on the lever, the Motec cuts fuel for ~100ms (it is programmed for a 300ms BUT as soon as it senses that the box is in the next gear, it lights the fire again). We log over 200 channels in the ECU and up-shifts take between 90 and 120ms - and the power seems absolutely seamless.

We did have a bit of rich misfire but tweaked the tune and eventually enabled close-loop lambda and picked up a couple of 10ths.

I found the limits of braking fairly quickly with a tour thru the kitty litter at T10 and the limits of grip on the sweeper with an off into wet grass but stayed away from the concrete.

Lap times are nothing special as we are 150hp down on the "fat" engine which will be in the car for a Nov race event but I am learning the car as braking and handling are staggeringly good.

The chassis is that stiff that if you jack the car from the front sill behind the front wheel, the rear rises at the same rate as the front - we reckon we have torsional stiffness of 25,000 kg per degree of torsional twist in the chassis which is why the handling is so good. We made a few suspension setup changes and you could feel the changes on the outlap.

There are still 16 items on the do-list (mirrors, oil/filter change, measure pad wear, minor maintenance items like that). Am really happy with where we are - has only been 7 years since this started but that's life when you are self employed and unsponsored

First event will be on 20-Aug with a 1-day club race event (quali and 3 x 20 minute races).

A few club track-days after that and then the fat engine goes in.