November 2009 Archives

I grew up in a Holden family in Melbourne. My grandfather owned an LH Torana 4 door with a 202 6 cylinder and 4 speed transmission and a VC Commodore. My Aunt and Uncle had an LC Torana. My parents owned a 1965 HD, a UC Sunbird, a VH Commodore SLR with the 4.2 V8 and a VL Commodore with the Nissan 6. Even my sister had a Gemini.

My first car was an LJ Torana SL coupe. It had a 173ci and a 3-on-the-tree. I rebuilt a 202 for it in my bedroom with a Yella Terra head, cam and roller rockers, installed a new clutch and "Speco" floor shifter. Unfortunately I thought it was faster than it really was, tried passing a friend in a Gemini, ran out of road and rolled it. Second car was a 4 door LJ with a 4 speed, that met the same fate as the first. I drove my parents HD for a while before ending up with an HX Kingswood wagon.

I had dreams of going circuit racing and bought another LJ rolling chassis 4 door, painted up like the HDT Malborough cars of the 70's with lots of racing goodies on it. I dropped in a 186ci and a Toyota 5 speed. The racing never panned out and I drove it on the street for a while before selling it and moving to the US in 98. I got $2500 for it, it would be worth $25,000 today.

My latest, and by far the nicest, Torana is a 1976 LX Hatchback. It has a 400ci small block Chevy, Turbo 400 and 9" Ford rear. Only thing I don't like about it is the paint, which although very nice, is impossible to keep clean as it shows every spec of dust. Once the Monaro is done I may build a Brock clone out of it. Actual pics of the Torana at US131 Motorsports Park below. Best time in good air is 12.38 seconds in the 1/4 mile.

Todays job was to finish the rough cutting and prep the rockers for the new cross member. I now have the floor cut out all the way up to the middle stamped steel cross member, and have removed the floor and rear frame members from the rocker panels. As I said in an earlier post, the Monaro construction differs from the 2nd gen Camaro by having the rear subframe spot welded directly to the rocker panels. So there are two rows of spot welds to cut from the inside rocker panel, where the upper floor panel and the lower frame rail mounts.

Be prepared to get dirty (like coal miner dirty) and lie on the floor a lot. Luckily today was sunny and relatively mild (for Michigan) so I had the garage door open to take advantage of the sunlight. I used the plasma to cut the floor panels and lower frame as close to the rocker panel without cutting into the rocker. I also trimmed 12" off the front subframe, which I will box and join to the rear frame cross member later. All the rust and paint is removed and ready for the 1/8" reinforcement plates.

This is the pile of stuff left over. There will be more to come from the rear valance, and possibly the inner fender wells. They may have to come out to clear the tires, I won't know until its all mocked up.

To get the wheels square in the wheel wells to measure axle width I made an adjustable jig from some old 10 bolt axles and a piece of rollbar tubing. The tubing is tapped for two 3/8 bolts to retain the axles in the tube. With the new wheel/tire combination its looking like an axle width of 48" instead of 55" with the old wheels and tires. Much more satisfactory. All in all a good days work.

By far the best tool for cutting anything metal is the plasma cutter. Mine came from Miller and is the Spectrum 375 Extreme. My welder is also a Miller (are you listening Miller? How about a little sponsorship?) and I will feature it later. The plasma cutter allows you to take out small pieces very quickly, and when you're not sure how a car is put together and what you might need to keep, its best not to chop out large chunks.

Next most useful is the trusty Sawzall with a 9" blade. The longer blade will cut through frame rails, top and bottom at the same time.

One tool I've not used before is the spot weld cutter, this one by Blair. You need to locate the spot welds (a wire brush can help, some are obvious, others not), center punch the middle of them, then use the cutter to cut around the weld. Be careful only to cut through the top piece and not into the metal underneath. I loved using this tool, but it was not long before the guide point blunted which made it chatter and broke the cutting teeth. I reground a point on it and reversed the blade and was back in business. The tool only cost $14 so if it only lasts one job its still worth having.

After cutting the spot welds, use the air chisel to remove the scrap piece. If you try chiseling through the spot welds without cutting them first you risk tearing a hole in the rocker panels underneath so I definitely recommend the spot weld cutter.

Other tools that most people have are a 4.5 inch angle grinder with cutting and grinding wheels, an air powered die grinder for removing paint and rust, and a scraper for removing seam sealer.

After mocking up the 29x10 tires under the car, I realized that just wasn't enough tire for the job. After all, the whole point of back-halfing is to get a bigger tire under the car, so why use the same size that were on before? As it happens I have a pair of 15x12 Weld Prostars sitting around for a Camaro project and decided to see how they would look. Enter the 29x12 Hoosier slicks. According to Hoosier the 29x10 tires are 29.1" tall, and the 29x12 are 29.3". Not much difference on paper, and should fit the wheel openings as well as the 10" tires. So off I go again to Lane Automotive to buy my new tires and get them fitted and balanced. Rich on the back counter is the guy to see about anything drag racing related. As you can see from the pics the new tire is quite a bit wider and taller than the old one, but it still fits the wheel well very nicely with about 1" of clearance all the way around. And thats about all I did today, other than get a new set of tires for my wifes minivan, which are not Hoosier slicks but Yokohama something or other from tirerack.com.

Well it didn't take long to come to that "what the hell am I doing" moment, cutting up a perfectly good car as I was. I started by chopping a big hole in the trunk (I know it's a boot but I will refer to it as a trunk) floor so I could get in there and have better access. First problem: most guys cut out the rear parcel shelf and replace it with lighter aluminum or sheet metal, but my trunk hinges are spot welded to the bottom of it so I have to retain it. I'm sticking with the original trunk lid and not replacing with the fiberglass which is what most racers would do.

The Monaro is built like a 2nd generation Camaro (1970-81) with a bolt on front subframe and a welded in stamped steel rear frame. Rear suspension is a triangulated 4 link like a Chevelle (or a Torana). One notable difference in the construction is the rear frame which, unlike a Camaro, runs from the rear valence forward, up over the axles, out to the rocker panels and halfway up the floor. The front subframe bolts directly to it, eliminating the need for subframe connectors. I haven't quite worked out where the new cross member will weld to, but it's looking like the rear frame will have to be completely removed from under the floor to gain access to the inside rocker panels. I'll then attach the rear of the front subframe to the new cross member using square tubing.

The tire/wheel combination I will be using is the same as before, 15 x 10 Weld Prostars and Hoosier 29 x 10 slicks. They look good tucked up and inside the quarter panels rather than sticking out as in the picture below. It may seem like a small tire but any taller and I would have to trim the quarters. Anyway there are guys running 7's in 10.5" tire classes so I should be ok in the low 10's, high 9's.

With the floor and inner wheel wells removed I can now place the tire where I want it to be and measure for my rear axle width and axle centerline. Using two squares lined up on the wheel rim, mark halfway between the squares. This is the axle centerline. Use a plumb bob to transfer the mark to quarter panel for later reference. Measure 38 inches from the axle CL forward and mark the rocker panel. This is where the cross member will be (for a ladder bar, 4 link is different). The floor will have to be removed up to this mark. Axle width will be 55", now that I know that I'll order up a fabricated 9" housing.

It's Thanksgiving eve here in the US, the night before a 4 day weekend. Tomorrow the Monaro goes into surgery. So far I have removed the rear end, cut out my old 12 point rollcage, and stripped the interior. The dash will be replaced with a sheetmetal one. You can see where the car was converted to left hand drive. They did a nice job but I don't understand why, its legal to drive a RHD car here (Torana is unconverted) and its more fun. However, for the benefits of weight distribution and picking up the timeslip after a run I will stick with RHD. The steering column will also get replaced with a lighter, race only piece. If anyone needs a set of GTS full instrumentation gauges drop me a comment.

The plumb bobs hanging from the quarters represent the rear axle centerline. All measurements for locating the rear frame are measured from it and the chassis centerline. The rear frame kit is by Chassis Engineering and was purchased from Lane Automotive, just up the road from here in Watervliet, MI. A little tip here, it was cheaper to purchase the components of the kit (Part #3628) separately, than it was to buy the whole kit. I opted for the Strange single adjustable coil-overs with 150# springs. It also comes with a nice how-to video from Chassis Engineering. I recommend getting the video before attempting this.

Tomorrow we cut...wish me luck!

Image Magick is installed and appears to be working. Here is an image of the Monaro on a pass at US131 Motorsports Park in Martin Michigan. This picture was taken in 2004 and I can tell by the aluminum radiator that I was running the 427 with a Dominator carb on racing gas. Later I tried Rons Flying Toilet alcohol injection and ran a best time of 10.79 @ 120mph until an intake valve dropped and destroyed the motor. That motor was replaced by a 452ci with a home-built alcohol injection system, best time 10.31 @ 125 mph. This proved to be too much for the stock chassis factory 4-link as the car was all over the track. Which brings me to my current project, the back-half ladderbar rear frame! 

This blog will be centered around drag racing and various garage projects. I currently own two GM Holdens, a 1973 Monaro GTS and a 1976 LX Torana Hatchback.The Monaro is a dedicated race car while the Torana is road registered but still runs 12.50's in the quarter. I was fortunate enough to buy these cars already in the US, at a motorcycle dealership in St Louis in 2001. Michael is an ex-pat Aussie like me and deals in antique motorbikes. Check him out at http://michaelsmotorcycles.com/

I hope you check back often to chart the progress of my projects and racing exploits.