tortfeaser
18-04-07, 03:04 PM
I though I should stick my car up here mainly as a bit of a project log. It’s a 1985 Holden JD Camira in PRC rally car trim. Sounds an odd choice for a rally car, but if you consider that the GM J series cars were rallied pretty successfully in Group A, especially as the Mk II Astra in the UK, it starts to make more sense. The concept is one of a lot of good mechanical bits available in a cheap shell. A lot of the stuff that was a problem in the road car is either replaced or modified in the rally car and all the good stuff remains – it handles well when setup right, is pretty light and torquey.
The car was one of three built around the same time, with the three builders sharing tips on design and setup. I think this is the last one of the three still competing. On the build – the cage was done by Norm Singleton in Qld, is 4130 CroMo, and seems to have stood up to two rolls really well. The shell hasn’t had a lot of work done, except some bracing between the front inner guards and firewall, around the rails, strut tops, and seat and belt mounts. A 10mm alloy sump guard and fibreglass underbody and tank protection help with the rocks.
The interior has the usually rally bits, terratrip, intercom, vid camera, extinguishers, oil pressure and temp, coolant temp and volts gauges. OBX seats (cheap, comfy and good) and 3” 5 point harnesses. Two roof vents are the biggest performance enhancer on a hot day.
Engine is the Family II 8v 2l motor, with forged pistons, Bill Blydenstein head, dunno what sort of cam, 4-1 extractors and throttle bodies from a Suzuki GSXR1000. Management is by Megasquirt running off the factory dizzy and sparking a single coil. When the motor is refreshed I’ll get rid of the dizzy and go to waste spark coils, change to 4-2-1 extractors, flow the head to see what’s what, reduce cam duration and increase lift (need more torque at less revs). I definitely need an airbox with a plenum instead of the current individual foam filters. Currently makes 93kW ATW and revs to 7600 rpm, though I usually change by 7k rpm. Cooling is by factory radiator with 87degC thermostat (that took some fitting), with oil cooler plumbed in with a sandwich plate. Coolant temps don’t get higher than 95degC. Oil temp now around 105decC instead of the 130degC previously.
Gearbox is Quaife F20 straight cut close ratio synchro internals in the F16 case – 2.54:1 1st, 1.04:1 5th, Quaife 4.5:1 Torsen diff. Running Redline lightweight shockproof though I don’t know why. At least leaks are easy to see. I’m going to have to put some synchros in it soon, but new parts are NLA from Holden, so I don’t know what I’m going to do.
Brakes are VP Commodore front and rears, 290mm front callipers, DS2500 pads on the front and Bendix Ultimates on the rear. There’s still too much rear bias despite a proportioning valve and those rear pads. I need to fit a bias adjustable pedal box with separate master cylinders.
Front CVs and bearings get replaced every few events. I’ve had problems with the CVs exploding when I stupidly drop the hammer on full lock. I need to fit some sort of lock stops.
Suspension is 55mm non canister, non adjustable Proflex (or whatever Murray Coote calls what he makes), in the standard struts with adjustable spring platforms. Steering arms have been shortened, and I’m running the factory power steering. Front and rear anti roll bars are standard, though I’m thinking of removing the rear one. Lower control arms have inboard rose joints to make camber and caster adjustable, though its not easy. Rose joints also on steering tie rods. I’d like to use the standard arms boxed in and have adjustable strut tops – would make changes and replacement easy but I’d need to go to smaller diameter springs and find some suitable tops. I struggle with oversteer and the car is very twitchy at speed – rear toe out is about 1mm and I can’t get rid of it easily (its not adjustable from the factory). I need to fix this as the first priority.
Tyres are black, round, and whatever I can get in good nick. Its getting harder to find good condition 195mm rally tyres without buying brand new, so that’s a cost that will increase soon.
When I bought it it looked like this:
http://users.tpg.com.au/goodship/Camira.jpg
Then I did this in my first competitive outing, a stupid mistake cutting a corner too deeply while still on the brakes:
http://users.tpg.com.au/goodship/100_1406.jpg
So I fixed it and did a couple of events:
http://users.tpg.com.au/goodship/tortcamira.jpg
http://users.tpg.com.au/goodship/foto0128sm.jpg
Before doing this on a called SO over crest which was really a R5 (pulled 4th, ended up in a gutter on the outside which broke a tie rod end spitting me across the road and upside down. Went through the flying finish on the lid, but 50s faster than the first run through that stage):
http://www.bmsc.com.au/gallery/data/500/medium/16-1.jpg
So now I’m fixing it again.
http://users.tpg.com.au/goodship/five.jpg
The car was one of three built around the same time, with the three builders sharing tips on design and setup. I think this is the last one of the three still competing. On the build – the cage was done by Norm Singleton in Qld, is 4130 CroMo, and seems to have stood up to two rolls really well. The shell hasn’t had a lot of work done, except some bracing between the front inner guards and firewall, around the rails, strut tops, and seat and belt mounts. A 10mm alloy sump guard and fibreglass underbody and tank protection help with the rocks.
The interior has the usually rally bits, terratrip, intercom, vid camera, extinguishers, oil pressure and temp, coolant temp and volts gauges. OBX seats (cheap, comfy and good) and 3” 5 point harnesses. Two roof vents are the biggest performance enhancer on a hot day.
Engine is the Family II 8v 2l motor, with forged pistons, Bill Blydenstein head, dunno what sort of cam, 4-1 extractors and throttle bodies from a Suzuki GSXR1000. Management is by Megasquirt running off the factory dizzy and sparking a single coil. When the motor is refreshed I’ll get rid of the dizzy and go to waste spark coils, change to 4-2-1 extractors, flow the head to see what’s what, reduce cam duration and increase lift (need more torque at less revs). I definitely need an airbox with a plenum instead of the current individual foam filters. Currently makes 93kW ATW and revs to 7600 rpm, though I usually change by 7k rpm. Cooling is by factory radiator with 87degC thermostat (that took some fitting), with oil cooler plumbed in with a sandwich plate. Coolant temps don’t get higher than 95degC. Oil temp now around 105decC instead of the 130degC previously.
Gearbox is Quaife F20 straight cut close ratio synchro internals in the F16 case – 2.54:1 1st, 1.04:1 5th, Quaife 4.5:1 Torsen diff. Running Redline lightweight shockproof though I don’t know why. At least leaks are easy to see. I’m going to have to put some synchros in it soon, but new parts are NLA from Holden, so I don’t know what I’m going to do.
Brakes are VP Commodore front and rears, 290mm front callipers, DS2500 pads on the front and Bendix Ultimates on the rear. There’s still too much rear bias despite a proportioning valve and those rear pads. I need to fit a bias adjustable pedal box with separate master cylinders.
Front CVs and bearings get replaced every few events. I’ve had problems with the CVs exploding when I stupidly drop the hammer on full lock. I need to fit some sort of lock stops.
Suspension is 55mm non canister, non adjustable Proflex (or whatever Murray Coote calls what he makes), in the standard struts with adjustable spring platforms. Steering arms have been shortened, and I’m running the factory power steering. Front and rear anti roll bars are standard, though I’m thinking of removing the rear one. Lower control arms have inboard rose joints to make camber and caster adjustable, though its not easy. Rose joints also on steering tie rods. I’d like to use the standard arms boxed in and have adjustable strut tops – would make changes and replacement easy but I’d need to go to smaller diameter springs and find some suitable tops. I struggle with oversteer and the car is very twitchy at speed – rear toe out is about 1mm and I can’t get rid of it easily (its not adjustable from the factory). I need to fix this as the first priority.
Tyres are black, round, and whatever I can get in good nick. Its getting harder to find good condition 195mm rally tyres without buying brand new, so that’s a cost that will increase soon.
When I bought it it looked like this:
http://users.tpg.com.au/goodship/Camira.jpg
Then I did this in my first competitive outing, a stupid mistake cutting a corner too deeply while still on the brakes:
http://users.tpg.com.au/goodship/100_1406.jpg
So I fixed it and did a couple of events:
http://users.tpg.com.au/goodship/tortcamira.jpg
http://users.tpg.com.au/goodship/foto0128sm.jpg
Before doing this on a called SO over crest which was really a R5 (pulled 4th, ended up in a gutter on the outside which broke a tie rod end spitting me across the road and upside down. Went through the flying finish on the lid, but 50s faster than the first run through that stage):
http://www.bmsc.com.au/gallery/data/500/medium/16-1.jpg
So now I’m fixing it again.
http://users.tpg.com.au/goodship/five.jpg