In order to pass registration tests, I needed "adequate" room between the whole drive-train and the body of the car. This means not only clearance within the engine bay, but also for exhaust pipes under the floor pans, then for exhausts to clear the rear coil-overs, clear around the custom fuel tank, etc. Most importantly the fuel supply lines need to be protected from exhaust heat, blown universal joints (eg, via tail-shaft loops), and so on. This all gets tricky with a 3-Link rear suspension setup and full (twin) 3" exhaust tubing.
Basically I needed to remove any possibility I could think of that an inspector could use to defect the car.
The single biggest change was to build up a new set of headers in stainless steel. My original set in mandrel bent mild steel "should" pass inspection - but I was right on the limit of the minimum 10mm gap required. And this must include when the engine rocks each way on its mounts under full acceleration/deceleration..
The trouble is, it is subjective as to how much deflection there may be in a set of engine mounts.....
So by making a new set of headers that have heaps more room, there should not be a problem (and I always wanted a stainless set anyway).
Even better is that if you simply buy a bunch of stainless mandrel bends, it ends up about half the price of a similar "build your own set of headers" kit. In my case $220 (AUD) got all the bends I needed (which was a mixed bag 4 x 45 degree, 4 x 90 degree, and 2 x 180 degree bends - all at the tightest radius offered). So $220, plus a day and a half of my own labour on top, got me the custom set I needed. here are the results:
This first photo kind of shows how I crossed pipes over to try and get them similar lengths.
And now the almost finished set. I was still yet to weld on flanges for a V-clamp connection to the rest of the exhaust system and weld in the O2 bungs.
As for my fuel rails, when I last had the motor at the dyno, I had run lots of braided hose and AN-8 "T" fittings to firstly divide my 1/2" high pressure fuels supply from the tank as it reach the middle of the engine valley, and then each of these ends divided again to supply fuel to the rails from each end. My thinking being that this would minimise any pressure drop to the "far" injector if I only supplied the rails from one end. Well my (way more experienced than me) dyno man said I'd over-thought it and over-complicated it. The rails themselves have heaps of volume each to counteract this risk. My "complicated" setup worked fine of course, but just wasn't needed and took up room. So I simplified things and now just split the 1/2" supply line once (via a single "T" junction at the firewall) and these two free ends now run straight into the back of each fuel rail.
This photo (and the next one with the engine back in the car) shows the rails have been cleaned up. This first one is also a good photo of the engine rocker stud girdle setup, dry sump reserve tank, etc too.
Then it came time to give it a test run on the street in prep' for its final inspection. It gets a rigorous cornering and braking test I'm told, so I do need to bed the brakes in, make sure all the undercarriage/suspension bolts are torqued up, no leaks appear, etc, etc. I went over everything several times and still found a loose dry sump pressure inlet line after its first outing! Doing this build solo risks such things.........
So how did it go?
OMG, "awesome and scary fast" is how my dad and son describe it. Not unsafe at all, I only jabbed it to just over half throttle for a moment. It was nicely predictable and didn't throw itself radically sideways (just a slight rear drift out to the left as it launched - easily corrected by a small steering tweak).
But saying traction is marginal with the power on tap - would be an understatement. Some suspension tuning would help a bit with this no doubt, but the power/torque available right off idle is amazing. Well we are talking serious cubes here but I'm pleasantly satisfied for now. Putting some decent timing into it since the dyno run seems have made it heaps more responsive.
And the music from the motor? That was indeed special as I had left the windshield off for the test drive (it stays off until my dash gets trimmed/covered). So the unblocked induction roar from 8.5 litres of the 8-Stack injection trumpets up front, plus the exhaust note out back was the best thing I'd heard in a while.
Here are a few photos of how it looks right now after this first run.
I can see from the picture above that my front valence is yet to be finished too.
This will include an integrated air inlet/scoop for cooling. It will be an all steel unit.
The photo above is another shot of how far back the big block is. There is plenty of engine bay daylight from the radiator to the heads.
So what's next?.... Well, dare I say it - "minor stuff"! I only need to get the interior trimmed (at least the dash) so I can put the windscreen in. Then for a roadworthy I need side and rear-view mirrors, plus run the cabling to hook up the handbrake to the rear disks. Oh, and probably the last thing is to put a windscreen washer bottle somewhere (accessible).
I will be putting in a cold-air box with integrated filters as well. This will draw cool air in though the hood scoops. This and other finishing pieces can wait for the next post.
Goodness me, light at the end of the tunnel 😊
