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Off season engine maintenance or swap?


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I don't share the same view re gearbox.  Having something geared such that the engine is kept more within its useable torque range, tolerates/demands positive/quick gear changing is going to be a better thing all round in a track/competitive environment.

I'll stand up and say a CA running 200kW with a CR dog box will probably be (depending on track and driver) equal or better than a 250kW SR running a standard box. 

End of the day, motorsport and car mods aren't cheap.  It's your choice, there's different views/perspectives.  Keep us updated with what course you take.

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Building a good reliable CA for track work isn't hard, I recently sold an S12 with a CA that put out 235rwkw and has great torque.

 The two best things I did to it were:

1) Crank trigger, get rid of the CAS aids (This car ran Autronic though so I'm not sure if Nistune will accept a crank trigger)

2) Moved the injectors so that they were further up the runners, the factory placement sprays fuel into one valve but not the other. I found quite a good increase in torque because we could crank in a bit more timing.

Engine was pretty basic, just 9:1 JE pistons and Spool rods, new OEM oil pump with a direct pressure take off fitting welded to the housing, Kando TD05-18G and NA cams.

The car handled like shit but still did 1:51 at the island no problem. I had quite a few pics but Photof**ket.

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I don't share the same view re gearbox.  Having something geared such that the engine is kept more within its useable torque range, tolerates/demands positive/quick gear changing is going to be a better thing all round in a track/competitive environment.
I'll stand up and say a CA running 200kW with a CR dog box will probably be (depending on track and driver) equal or better than a 250kW SR running a standard box. 
End of the day, motorsport and car mods aren't cheap.  It's your choice, there's different views/perspectives.  Keep us updated with what course you take.
Big call!
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Building a good reliable CA for track work isn't hard, I recently sold an S12 with a CA that put out 235rwkw and has great torque.
 The two best things I did to it were:
1) Crank trigger, get rid of the CAS aids (This car ran Autronic though so I'm not sure if Nistune will accept a crank trigger)
2) Moved the injectors so that they were further up the runners, the factory placement sprays fuel into one valve but not the other. I found quite a good increase in torque because we could crank in a bit more timing.
Engine was pretty basic, just 9:1 JE pistons and Spool rods, new OEM oil pump with a direct pressure take off fitting welded to the housing, Kando TD05-18G and NA cams.
The car handled like shit but still did 1:51 at the island no problem. I had quite a few pics but Photof**ket.
A real CA user! Well, you were.

Did you do any specific testing re the crank trigger to gauge actual gains?

Have never heard that re the injector location, got a pic?
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I've still got a CA, it's just two extra cylinders!

We did some testing with timing scatter on the dyno with a Snap-On timing light and a scope which showed some pretty frightening variations in timing through the mid range and it was all over the joint up top. I think this is largely due to 30 year old sensors trying to keep up and just failing.

Following crank trigger install it was a completely different beast, in fact that was the very first change I made to my Rb after my previous experience.

We also took out those stupid NICS butterflys when I moved the injectors. 

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Nah, I made the crank trigger myself. Still used the CAS for the sync signal though. You only really need 4 teeth so I just made up a plate that bolted onto the back of the balancer with a GT101 in between the timing belt behind the front cover.

You won't realise the benefit of moving the injectors if you keep the butterflies in there. If you are racing the car, it should never be below 3000rpm and therefore the butterflies are useless since you have enough air speed at 3000rpm and boost is building so they are just a restriction. 

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3 hours ago, Dale FZ1 said:

I don't share the same view re gearbox.  Having something geared such that the engine is kept more within its useable torque range, tolerates/demands positive/quick gear changing is going to be a better thing all round in a track/competitive environment.

I'll stand up and say a CA running 200kW with a CR dog box will probably be (depending on track and driver) equal or better than a 250kW SR running a standard box. 

End of the day, motorsport and car mods aren't cheap.  It's your choice, there's different views/perspectives.  Keep us updated with what course you take.

This guy

He knows.

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Nah, I made the crank trigger myself. Still used the CAS for the sync signal though. You only really need 4 teeth so I just made up a plate that bolted onto the back of the balancer with a GT101 in between the timing belt behind the front cover.
You won't realise the benefit of moving the injectors if you keep the butterflies in there. If you are racing the car, it should never be below 3000rpm and therefore the butterflies are useless since you have enough air speed at 3000rpm and boost is building so they are just a restriction. 
Not familiar with GT101, will Google.

I don't have fabrication skills to make trigger discs.
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https://www.efihardware.com/products/358/gear-tooth-sensor-1GT101DC

Super easy to fabricate, just draw it on an open source CNC program like E machine shop and send it off. Should cost less than $200 for the whole lot.

If you want any GT101's let me know I've moved on to a Bosch Motorsport sensor for my RB  because of extra teeth and have a few new ones lying around.

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Yes, the ecu still needs to know where the camshafts are up to but the crank trigger keeps your fuel and spark events on time in relation to the piston location. It'd be work looking at whether Nistune can run a crank trigger though.

I'm assuming you don't still have the AFM? That's just more aids you need to banish!

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15 hours ago, Komdotkom said:

Building a good reliable CA for track work isn't hard, I recently sold an S12 with a CA that put out 235rwkw and has great torque.

 The two best things I did to it were:

1) Crank trigger, get rid of the CAS aids (This car ran Autronic though so I'm not sure if Nistune will accept a crank trigger)

2) Moved the injectors so that they were further up the runners, the factory placement sprays fuel into one valve but not the other. I found quite a good increase in torque because we could crank in a bit more timing.

Engine was pretty basic, just 9:1 JE pistons and Spool rods, new OEM oil pump with a direct pressure take off fitting welded to the housing, Kando TD05-18G and NA cams.

The car handled like shit but still did 1:51 at the island no problem. I had quite a few pics but Photof**ket.

Finally sold the S12 eh, I was interested in it at one stage but at that time the flexy chassis and semi trailing arm rear suspension put me off. Now I'd give it a go having since learnt lots about that suspension and a derivative.

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