Duke Racing Celica GT-Four Time Attack Racecar
- Thread starter Punknoodle
- 1,059 comments
- 146,291 views
- 3,211
- Brisbane
- Punknoodle_Nick
Ideal size is 5x100 17x9 35et. Was looking at Gram Lights but they don't come in that size. The car felt great on the SSRs which are heavier than the PF01s so I'm not too worried about the weight. The big benefit to me is the clearance for the brakes as I'm intending to fit a fairly decent sized set in there.
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- 4,604
- The Netherlands
- GTP_PASM
That's not as far inset as I thought from the pictures. For aesthetics, I would go for the PF01 over RPF1. But I really hate wheels that have the heart too far outward with spokes that go inward. One example:
I see some PF01 in certain sizes that also have the same effect, and some that don't. I don't know if that is the case in your preferred size and ET value.
I see some PF01 in certain sizes that also have the same effect, and some that don't. I don't know if that is the case in your preferred size and ET value.
- 3,211
- Brisbane
- Punknoodle_Nick
Yeah I know what you mean, if you require a high offset normally you are better off choosing more of a flat face design as the wheels that are designed to be concave look silly when they need to be offset towards the face. The SSRs I had actually still managed to have some lip in the +35 offset, I really liked them but they had bugger all brake clearance.That's not as far inset as I thought from the pictures. For aesthetics, I would go for the PF01 over RPF1. But I really hate wheels that have the heart too far outward with spokes that go inward. One example:
I see some PF01 in certain sizes that also have the same effect, and some that don't. I don't know if that is the case in your preferred size and ET value.
This is what the PF01s look like in a +35 offset though, it's quite nice I think, and plenty of clearance:
Images from this thread.
If anyone wants to do a photoshop then I'd welcome it!
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- 3,211
- Brisbane
- Punknoodle_Nick
I've got the car all booked in with the fabricator to get the Cams spec 4 point cage done. It's going in on the 26th Feb so I'm really looking forward to that being finished.
In the mean time, I was sitting looking in to the engine bay again and I decided that I just couldn't live with the wastegate bracket that I made a while ago. It's never really been tested, I'm sure it would have worked just fine, but it was heavy, ugly and really fiddly to fit. I hated it. So I uninstalled it and threw it in to the failed prototype storage area and began work on the new and improved version.
I've ordered a new Turbosmart IWG 75 twin port actuator with the correct clevis to suit my turbo. This actuator alone is a good upgrade anyway as being a twin port it helps to hold the wastegate shut even with high exhaust pressure. Because I'm going to be running E85 which has a higher exhaust volume than regular fuel I figured this was probably a good idea.
I've also gone to see a local aluminium place to ask if they had any offcuts of 10mm plate. Picked up a piece about 5 times larger than I needed for 5 bucks and set about cutting the shape I needed. It was a bit of a pain but I'm pretty happy with the result and I think it will weld on to the compressor housing just fine.
So now I just need to get that welded and this will be the new support for the waste gate. The compressor housing will be painted and then I'll need to make a nice small bracket to go between the compressor housing and the actuator. It will be a simple Z shape out of stainless rather than the big monstrosity that was there before and should work well.
In the mean time, I was sitting looking in to the engine bay again and I decided that I just couldn't live with the wastegate bracket that I made a while ago. It's never really been tested, I'm sure it would have worked just fine, but it was heavy, ugly and really fiddly to fit. I hated it. So I uninstalled it and threw it in to the failed prototype storage area and began work on the new and improved version.
I've ordered a new Turbosmart IWG 75 twin port actuator with the correct clevis to suit my turbo. This actuator alone is a good upgrade anyway as being a twin port it helps to hold the wastegate shut even with high exhaust pressure. Because I'm going to be running E85 which has a higher exhaust volume than regular fuel I figured this was probably a good idea.
I've also gone to see a local aluminium place to ask if they had any offcuts of 10mm plate. Picked up a piece about 5 times larger than I needed for 5 bucks and set about cutting the shape I needed. It was a bit of a pain but I'm pretty happy with the result and I think it will weld on to the compressor housing just fine.
So now I just need to get that welded and this will be the new support for the waste gate. The compressor housing will be painted and then I'll need to make a nice small bracket to go between the compressor housing and the actuator. It will be a simple Z shape out of stainless rather than the big monstrosity that was there before and should work well.
- 3,211
- Brisbane
- Punknoodle_Nick
Update - the new wastegate is all finished. Here is what the compressor housing looked like after it was painted (with high temp silver paint):
I then made a little bracket out of 2mm stainless. I have to admit, it was a complete PITA to get it right. The actuator needs to clear everything, the rod needs to clear everything throughout it's travel, and the angle of it has to be right to get the full stroke of the actuator..
Here is how it looks all installed:
I've tested it with compressed air and it works nice and smooth, it's nice and compact and simple and lines up beautifully so I'm pretty happy with it. I've plumbed it properly using the dual port method so it should work well.
Complete engine bay shot:
Next little tidy up job before it goes off to the fabricator is a little heat shield around the air filter. After that, aside from swapping injectors and spark plugs I'm pretty much done in engine bay.
I then made a little bracket out of 2mm stainless. I have to admit, it was a complete PITA to get it right. The actuator needs to clear everything, the rod needs to clear everything throughout it's travel, and the angle of it has to be right to get the full stroke of the actuator..
Here is how it looks all installed:
I've tested it with compressed air and it works nice and smooth, it's nice and compact and simple and lines up beautifully so I'm pretty happy with it. I've plumbed it properly using the dual port method so it should work well.
Complete engine bay shot:
Next little tidy up job before it goes off to the fabricator is a little heat shield around the air filter. After that, aside from swapping injectors and spark plugs I'm pretty much done in engine bay.
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- 3,211
- Brisbane
- Punknoodle_Nick
Gave the car a quick wash and wax for the last time before it goes on the trailer to get dropped off to the fabricator on Monday. I've been waiting ages for this, really excited to see how the rollcage turns out!
- 3,211
- Brisbane
- Punknoodle_Nick
On Monday I loaded the car on to a mate's trailer and headed down to the fabricator..
On Thursday he contacted me to ask a couple of questions and he sent me this small update:
The factory reinforcing between the strut towers is going to be removed to enable him to get a full weld across the new support bar. The new bar is stronger anyway and higher so will provide more stiffness. The bars coming down to the back from the main hoop will be then tied to the new bar.
The main hoop is going to have an X brace through it as well as a harness bar the full width so I can run a passenger harness. Should have some more photos next week.
On Thursday he contacted me to ask a couple of questions and he sent me this small update:
The factory reinforcing between the strut towers is going to be removed to enable him to get a full weld across the new support bar. The new bar is stronger anyway and higher so will provide more stiffness. The bars coming down to the back from the main hoop will be then tied to the new bar.
The main hoop is going to have an X brace through it as well as a harness bar the full width so I can run a passenger harness. Should have some more photos next week.
- 3,211
- Brisbane
- Punknoodle_Nick
End of week update:
The factory brace was removed and the new one tacked in to place. This is low to accommodate the regulated rear brace angle, plus to try and keep the centre of gravity down:
The main hoop was tested in position:
This was removed again and work began on adding the harness bars in to the main hoop design.
A close up shot of the beautiful tig welding work:
These have been done using a dual pass, that is a root weld then a cap weld over the top.
Next up are the bars from top of main hoop back to rear support with a diagonal brace, then rear stays from the bottom of the hoop back to the rear support. This adds rigidity.
The factory brace was removed and the new one tacked in to place. This is low to accommodate the regulated rear brace angle, plus to try and keep the centre of gravity down:
The main hoop was tested in position:
This was removed again and work began on adding the harness bars in to the main hoop design.
A close up shot of the beautiful tig welding work:
These have been done using a dual pass, that is a root weld then a cap weld over the top.
Next up are the bars from top of main hoop back to rear support with a diagonal brace, then rear stays from the bottom of the hoop back to the rear support. This adds rigidity.
- 3,211
- Brisbane
- Punknoodle_Nick
Meet Mick from All Performance Garage:
Here are some more close ups of his handy work:
Mick has been hard at work for another week on the car and the cage work is pretty much completed. Here is what it looked like once the upper rear stays and diagonal brace were added:
Then, in went the lower rear stays:
And then the rear gusset plate to the floor:
Final welding has been completed now and tomorrow is going to be spent putting everything back in the car. The engineer is booked in for Friday who will mod plate the car which basically means the car is re-registered as a 2 seater only and that the cage work is street legal and I can remain driving it on the road. Inspection papers have gone off to CAMS to certify the cage for competition use. There is one little extra job that needs to happen tomorrow which is making a new bracket off the main hoop to hold my battery isolator as I want to run a smaller battery.
So, I should be picking it up some time next week, I'll probably book a day off work to do so. Then the fun begins on working out how I'm going to paint it. I found that the spray paint I used to paint the bonnet worked really well so I'll be using the same again, in the same colour. I'm going to buy a heap of that thin plastic drop sheeting, heaps of masking tape and attempt to mask off everything inside the car. I realize it's going to be a complete PITY, especially the wet sanding...
I'll figure it out...
Unfortunately time is going to be the biggest factor. I'm pretty busy in the weekends at work and during the Easter weekend I have a project down in Melbourne, but I'll try to lock down a couple of weekends that I can work on the car.
Oh, and here's a game for everyone except GDII (as we already played this lol). Name the track in my Avatar...
Here are some more close ups of his handy work:
Mick has been hard at work for another week on the car and the cage work is pretty much completed. Here is what it looked like once the upper rear stays and diagonal brace were added:
Then, in went the lower rear stays:
And then the rear gusset plate to the floor:
Final welding has been completed now and tomorrow is going to be spent putting everything back in the car. The engineer is booked in for Friday who will mod plate the car which basically means the car is re-registered as a 2 seater only and that the cage work is street legal and I can remain driving it on the road. Inspection papers have gone off to CAMS to certify the cage for competition use. There is one little extra job that needs to happen tomorrow which is making a new bracket off the main hoop to hold my battery isolator as I want to run a smaller battery.
So, I should be picking it up some time next week, I'll probably book a day off work to do so. Then the fun begins on working out how I'm going to paint it. I found that the spray paint I used to paint the bonnet worked really well so I'll be using the same again, in the same colour. I'm going to buy a heap of that thin plastic drop sheeting, heaps of masking tape and attempt to mask off everything inside the car. I realize it's going to be a complete PITY, especially the wet sanding...
I'll figure it out...Unfortunately time is going to be the biggest factor. I'm pretty busy in the weekends at work and during the Easter weekend I have a project down in Melbourne, but I'll try to lock down a couple of weekends that I can work on the car.
Oh, and here's a game for everyone except GDII (as we already played this lol). Name the track in my Avatar...
- 3,211
- Brisbane
- Punknoodle_Nick
No takers? It was Barbagallo 
Anyway I picked up the car on Tuesday and brought it home. I am beyond happy with the workmanship of the cage; it looks so much better in person. Here are some better photos:
Because the battery box no longer fits I'm planning on swapping to a smaller motorsport battery. Mick made a little bracket for the battery isolator and welded it onto the frame for me:
So today I spent a few hours masking up the inside of the car, then I started laying down a few coats of paint:
It's coming up ok - nowhere near as easy to lay down as the bonnet as the bars are all at difficult angles. The floor is another issue and I'll probably go back to brushing that on.
Anyway I picked up the car on Tuesday and brought it home. I am beyond happy with the workmanship of the cage; it looks so much better in person. Here are some better photos:
Because the battery box no longer fits I'm planning on swapping to a smaller motorsport battery. Mick made a little bracket for the battery isolator and welded it onto the frame for me:
So today I spent a few hours masking up the inside of the car, then I started laying down a few coats of paint:
It's coming up ok - nowhere near as easy to lay down as the bonnet as the bars are all at difficult angles. The floor is another issue and I'll probably go back to brushing that on.
- 3,211
- Brisbane
- Punknoodle_Nick
- 3,211
- Brisbane
- Punknoodle_Nick
Well I got the painting of the cage itself done, with base colour and clear. I didn't go to the same extent as I did with the bonnet, that is, wet sand smoothing the primer, nice even coats etc. It's pretty much just sprayed on right on top of the primer then clear on that.
The result is less than smooth in some places and a couple of runs here and there but generally on the most obvious places it came up pretty good. By removing all the masking it looks even better:
In this shot you can see where the harness straps end up - the bar is at the perfect height, the straps are horizontal back to the bar and within 200mm to satisfy HANS device installation requirements:
It feels really good to be strapped in to the seat properly now, really supportive and I think being so rigid will help me focus more on how the car is gripping in the corner. I can't wait
One thing that will be changing obviously is the helmet - I'll need a HANS compatible one, currently on the top of my list is the Arai GP6.
Next I started rerouting the cabling for my main battery cable now that there is a new switch location:
I'm going to make a little panel which will hold the fuel pump relay etc and redo that wiring next, but I just set up up temporarily tonight to start the car. Yep, still runs lol.
Lastly, today I ordered my new race rims. They are Enkei PF01s in 17x8 +35 in silver. Sample below:
These will take approximately 8 weeks to arrive though. So, progress is happening. It's a little slow, but I'm getting excited now as I'm pretty close now to being able to drive it again.
The result is less than smooth in some places and a couple of runs here and there but generally on the most obvious places it came up pretty good. By removing all the masking it looks even better:
In this shot you can see where the harness straps end up - the bar is at the perfect height, the straps are horizontal back to the bar and within 200mm to satisfy HANS device installation requirements:
It feels really good to be strapped in to the seat properly now, really supportive and I think being so rigid will help me focus more on how the car is gripping in the corner. I can't wait
One thing that will be changing obviously is the helmet - I'll need a HANS compatible one, currently on the top of my list is the Arai GP6.
Next I started rerouting the cabling for my main battery cable now that there is a new switch location:
I'm going to make a little panel which will hold the fuel pump relay etc and redo that wiring next, but I just set up up temporarily tonight to start the car. Yep, still runs lol.
Lastly, today I ordered my new race rims. They are Enkei PF01s in 17x8 +35 in silver. Sample below:
These will take approximately 8 weeks to arrive though. So, progress is happening. It's a little slow, but I'm getting excited now as I'm pretty close now to being able to drive it again.
- 3,211
- Brisbane
- Punknoodle_Nick
- 3,211
- Brisbane
- Punknoodle_Nick
Took the car outside the other day and took some better photos of the interior pretty much finished. I have done one minor thing since these photos though and that's completely rewired the fuel pump circuit. It's much tidier now and also uses bigger wiring as I decided the old wiring was right on the edge and I wanted to reduce voltage drop as much as possible. The battery will also be changed to a AGM battery as I no longer have it in a box.
Also, the registration sticker from CAMS arrived so now cage is officially certified for motorsport use
This waiting is killing me I want to get out and drive this thing...
Also, the registration sticker from CAMS arrived so now cage is officially certified for motorsport use
This waiting is killing me I want to get out and drive this thing...
- 3,211
- Brisbane
- Punknoodle_Nick
Filled up my first can of E85 today to put in the GT-Four. That's a milestone event!
Since the last update:
First up I ditched the old battery and replaced it with a Full River AGM battery. I am now using M8 terminals on the battery which is a lot tider and more secure than the posts on the old battery.
I had to make some little plastic spacers to fill up the sides of the clamp to limit movement.
I also received my new injectors from Injector Dynamics. These were the ID1050X injectors but unfortunately I had to return them as they didn't fit.. The wiring connector was too low and fouled on the cylinder head.
I replaced these with a full length Bosch 1000cc injector and wired the new USCAR connectors to my loom with some new Weatherpack crimpers and so now the fuel system is finished.
Tomorrow I'll pour in the E85 and try to get it idling nicely.
Since the last update:
First up I ditched the old battery and replaced it with a Full River AGM battery. I am now using M8 terminals on the battery which is a lot tider and more secure than the posts on the old battery.
I had to make some little plastic spacers to fill up the sides of the clamp to limit movement.
I also received my new injectors from Injector Dynamics. These were the ID1050X injectors but unfortunately I had to return them as they didn't fit.. The wiring connector was too low and fouled on the cylinder head.
I replaced these with a full length Bosch 1000cc injector and wired the new USCAR connectors to my loom with some new Weatherpack crimpers and so now the fuel system is finished.
Tomorrow I'll pour in the E85 and try to get it idling nicely.
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- 3,211
- Brisbane
- Punknoodle_Nick
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- 9,473
- QLD, Down Under
- GTP_Paulie
- Paulie LDP
I'm not on social media at all, but I know I haven't been around on the forums a lot either and it looks like I've missed a lot, the car has come so far! All I can say is, don't be a total stranger mate.👍
- 3,211
- Brisbane
- Punknoodle_Nick
Hi all, I thought I'd update this as I'm sitting here watching Le Mans and thought about this forum.
A few things have happened with the car since this was last updated and I said I would stop updating it lol.. Firstly, it's been tuned at 101 Motorsport and everything went well. It made 191awkw at 17psi of boost. The fuel composition was actually around 70% Ethanol, partly because there was a slight amount of 98 in the tank (just below the fuel pick up level) and partly because it's winter and the composition of pump ethanol changes slightly to aid in cold starting. Because of this, as I keep adding in new E85 and the composition works its way up to 85% I need to monitor the air fuel ratio to ensure it's not running too lean. In saying that, due to it being a track car and fuel economy not being an issue, it's been tuned nice and fat so my tuner believes there is room in the tune for when it is sitting at 85%. It's not a hard job to add a bit of fuel though so it's something I'll monitor. No timing changes will need to be made however.
Anyway, long story short - it's tuned and seems to run really well. I only drove it home and put it straight up on jacks again as my new wheels haven't arrive yet (due next week) and I've also ordered the new brakes!
Now, the brakes are something I'm actually really excited about. The standard brakes were probably the weakest part of the car at the track. Even with upgraded pads and rotors, plus high temp fluid they would still get terrible fade after as little as 2 or 3 laps. The new brakes should be much better.
For the rear - I already had the ST205 calipers I bought second hand, and I ordered some RDA discs to suit these, as well as a caliper overhaul kit and some new lines. I already had braided lines but I wasn't very happy with them so I replaced them. The old rotors were 288mm in diameter, and 10mm thick (non vented). The new rotors are 315mm in diameter and 16mm thick (vented) with dimples and slots. The calipers have gone from single piston to 2 piston and the pad area is significantly larger so I think these will be an excellent upgrade. Whilst doing the swap I also rebuild the handbrake assemblies and rebuilt the calipers with new pistons and seals, however I needn't have - they came out looking immaculate. For pads I chose Hawk HP Plus compound pads.
Old vs New rear brakes.
For the front I went custom - Barry from MRP Performance in New Zealand designed a kit to suit. The original front rotors were 278mm in diameter, and 25mm thick (vented). The new rotors I am getting are 330mm in diameter and 32mm thick (vented). They are also a floating 2 piece design, so the central mounting hat is aluminium and the rotor is attached to this using bobbins so it has flex and expansion. The calipers are Wilwood Superlite 4 piston calipers with Pagid RST3 compound pads. These are huge compared to the standard brakes and I'm really looking forward to leaning on them at the track, knowing that when I press the brake I'll actually have a pedal, which is something I couldn't trust with my old setup.
Sample of what the new kit will look like (same rotor and caliper, however mine are 5 stud, obviously)
So the car is very close to being ready for a shake down. The rears are fitted, fronts shouldn't be far away, wheels are nearly here so it was time to head to the racing shop and kit myself out with some new safety gear.
I bought a Sparco gear pack with includes a suit, gloves, boots, balaclava and socks. I also bought a new helmet - Arai GP6s and HANS device. I've never used a HANS before and I think it will take a bit of getting used to, but it all feels pretty good when sitting in the car.
New helmet and HANS.
New suit.
For the sake of completion I'll probably make another post here when it's all back together and hitting the track but in the mean time, I'll keep Instagram and Facebook updated with the nitty gritty stuff For now, the car sits like this:
A few things have happened with the car since this was last updated and I said I would stop updating it lol.. Firstly, it's been tuned at 101 Motorsport and everything went well. It made 191awkw at 17psi of boost. The fuel composition was actually around 70% Ethanol, partly because there was a slight amount of 98 in the tank (just below the fuel pick up level) and partly because it's winter and the composition of pump ethanol changes slightly to aid in cold starting. Because of this, as I keep adding in new E85 and the composition works its way up to 85% I need to monitor the air fuel ratio to ensure it's not running too lean. In saying that, due to it being a track car and fuel economy not being an issue, it's been tuned nice and fat so my tuner believes there is room in the tune for when it is sitting at 85%. It's not a hard job to add a bit of fuel though so it's something I'll monitor. No timing changes will need to be made however.
Anyway, long story short - it's tuned and seems to run really well. I only drove it home and put it straight up on jacks again as my new wheels haven't arrive yet (due next week) and I've also ordered the new brakes!
Now, the brakes are something I'm actually really excited about. The standard brakes were probably the weakest part of the car at the track. Even with upgraded pads and rotors, plus high temp fluid they would still get terrible fade after as little as 2 or 3 laps. The new brakes should be much better.
For the rear - I already had the ST205 calipers I bought second hand, and I ordered some RDA discs to suit these, as well as a caliper overhaul kit and some new lines. I already had braided lines but I wasn't very happy with them so I replaced them. The old rotors were 288mm in diameter, and 10mm thick (non vented). The new rotors are 315mm in diameter and 16mm thick (vented) with dimples and slots. The calipers have gone from single piston to 2 piston and the pad area is significantly larger so I think these will be an excellent upgrade. Whilst doing the swap I also rebuild the handbrake assemblies and rebuilt the calipers with new pistons and seals, however I needn't have - they came out looking immaculate. For pads I chose Hawk HP Plus compound pads.
Old vs New rear brakes.
For the front I went custom - Barry from MRP Performance in New Zealand designed a kit to suit. The original front rotors were 278mm in diameter, and 25mm thick (vented). The new rotors I am getting are 330mm in diameter and 32mm thick (vented). They are also a floating 2 piece design, so the central mounting hat is aluminium and the rotor is attached to this using bobbins so it has flex and expansion. The calipers are Wilwood Superlite 4 piston calipers with Pagid RST3 compound pads. These are huge compared to the standard brakes and I'm really looking forward to leaning on them at the track, knowing that when I press the brake I'll actually have a pedal, which is something I couldn't trust with my old setup.
Sample of what the new kit will look like (same rotor and caliper, however mine are 5 stud, obviously)
So the car is very close to being ready for a shake down. The rears are fitted, fronts shouldn't be far away, wheels are nearly here so it was time to head to the racing shop and kit myself out with some new safety gear.
I bought a Sparco gear pack with includes a suit, gloves, boots, balaclava and socks. I also bought a new helmet - Arai GP6s and HANS device. I've never used a HANS before and I think it will take a bit of getting used to, but it all feels pretty good when sitting in the car.
New helmet and HANS.
New suit.
For the sake of completion I'll probably make another post here when it's all back together and hitting the track but in the mean time, I'll keep Instagram and Facebook updated with the nitty gritty stuff
For now, the car sits like this:
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- 93
- United States
- GreenGhost74
That is one fantastic GT4, very nicely done. Can’t wait to see it back on track 👍
- 3,211
- Brisbane
- Punknoodle_Nick
I promised a post when the car is back together and ready to hit the track so, after over a year of development, here it is!
The custom brake upgrade kit from MRP in New Zealand is awesome - everything was top quality. Here is what one side looked like unassembled:
On the car without pads:
Behind the wheel:
The car now has sticky Nankang AR1 235/40 semis all round and has been given a good alignment. I'm taking it out to QR on Thursday for a bit of a shakedown and testing. Nervous, but really excited!
The custom brake upgrade kit from MRP in New Zealand is awesome - everything was top quality. Here is what one side looked like unassembled:
On the car without pads:
Behind the wheel:
The car now has sticky Nankang AR1 235/40 semis all round and has been given a good alignment. I'm taking it out to QR on Thursday for a bit of a shakedown and testing. Nervous, but really excited!
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