850 Sport Coupe series 2 track car.

ramona300

True Classic
Sunday at the local hillclimb.
 

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ramona300

True Classic
This is my last run of the day on Sunday. Only managed 4 runs because of delays caused by two cars rolling! For all 4 runs I used Tunerstudio on the tablet to adjust the fuel maps using the auto tune function. Normally I do this at the circuit but the hillclimb uses cells in the map that are never seen at the circuit.
 

ramona300

True Classic
Still plodding along with my new engine. Suzuki pistons and conrods installed. The old camshaft is there to drive the oil pump.
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The Triger belt timing conversion back plate has to be cut down yet to allow for the SOHC belt.
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The Suzuki head is just sitting there so I can check there is enough room to clear the starter motor. The rest of the intake has to be fabricated yet but this time the supercharger will be mounted much lower.
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The exhaust side still needs cleaning up. I went a bit crazy and bought set of full race SS headers from Germany for this engine but they will go on the current engine first.
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ramona300

True Classic
I bought the Triger belt conversion cheap but it was missing the drive piece on the end of the camshaft that connects to the camshaft pulley. Surprisingly lots of hours fabricating and then turning up on the lathe. The alloy backing plate from Triger holds the oil seals and seals off the bottom for the sump. I cut off the edges so the belts can operate. The camshaft is only there to drive the oil pump.
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ramona300

True Classic
Practice day at the local circuit on Wednesday. The car ran well all day but I did have a broken throttle cable which was annoying. Just the engine end broke so I managed a fix! I used the audio from an exterior camera which gives a far more realistic sound than what the interior camera has.
 

kmead

Glutton for punishment
Practice day at the local circuit on Wednesday. The car ran well all day but I did have a broken throttle cable which was annoying. Just the engine end broke so I managed a fix! I used the audio from an exterior camera which gives a far more realistic sound than what the interior camera has.
That is a lot of turning of the wheel…

Looks good. Nice driving.
 

NM850

True Classic
Yes. I have to weld a 180 degree section then a 18 inch SS hot dog style muffler out the rear panel. The photo is not my car, I will have the muffler pointing upwards out the lower section of the panel.View attachment 65249
Even my original Abarth exhaust points forward and turns but maybe only 140 Deg . Must have something to do with ideal exhaust length.
 

ramona300

True Classic
Even my original Abarth exhaust points forward and turns but maybe only 140 Deg . Must have something to do with ideal exhaust length.
I would say so. The 4 primaries are the same length and there needs to be some pipe there ahead of the muffler and after.
 

ramona300

True Classic
Dropped off the old exhaust today and started welding the new stuff together. That old one was starting to look a bit tatty!
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ramona300

True Classic
Run the engine today for a bit of a listen! I had done some before and after sound level comparisons with the microphone in the same place.
Old headers. New expensive SS.
Idle 89db 90db
3000rpm 95db 99db
rev for maximum reading 109db 113db

This was in my shed with the car on the trailer, microphone inline with the exhaust and about 800mm away. The old headers had a nail-sized hole in one runner and a crack in a weld about 15mm long! Sitting in the car the new item was quieter and a deeper tone. The holes must have let a fair bit of the noise out into the rear compartment. I did notice the AFR's were a bit richer, so there will be a bit of tuning required.
 

GregS

ProjectX
Looking good. Do you have a noise limit at your local tracks?
This is my re-skinned re-packed muffler from last week, should pass most noise tests.
 

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ramona300

True Classic
Looking good. Do you have a noise limit at your local tracks?
This is my re-skinned re-packed muffler from last week, should pass most noise tests.
The hill climb doesn't do sound checks but Wakefield part certainly did. Bloke would stand behind the car and ask you to hold 3000 rpm. Sometimes only once during an event but sometimes every time you lined up. 95db is the limit. There are 2 test points on the circuit as well. Same goes for Eastern Creek and Pheasant Wood. The tests I did above were with the rear panel and engine cover off on my garage with a work bench just behind so there was a lot of extra noise. I did audio recordings of before and after and it does not sound any louder but I can actually hear the exhaust leak now! I have not been black-flagged for noise as some people have but I intend to make a slip on bend that I can just hold on to the end with a hose clamp just in case.
 

ramona300

True Classic
This is the original 4 into one header. I cut just below the collector with the mini grinder and also just behind the 02 sensor bung. I knew there was a nail sized hole in the side of the collector but the split about 50mm long was a bit of a surprise! There was also a nail sized hole in the pipe below the O2 sensor bung so the AFR's are going to need some extra tuning. I noticed at the last few track days I was running out of top speed down the straight. I think I found the problem!
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ramona300

True Classic
Trackday on Monday at the Druitt circuit Sydney Motorsport Park. Unfortunately, it was wet, very wet! First outing with the new exhaust. I had some tuning of the fuel map on the trailer but I had planned to use the auto analyse function of the tuning programme to adjust the AFR's as I drove the circuit Because of the crack in the old headers about 400mm upstream of the O2 sensor the extra oxygen would have caused the sensor to signal to the ECU to add more fuel. I knew the mixture would be very rich at first but the auto-tune normally sorts this quickly. I started the computer programme before I drove to the dummy grid and sat there with the engine running. I should have been mid grid but I elected to go out last. Unfortunately, there was a delay while some car was recovered and I shut down the engine which also stopped my tuning. When I restarted the engine I forgot to restart the tuning and headed out for the practice session with the rich AFR's. It was fairly miserable on the track with the rain. The car ran well and sounded good, quieter inside I think. Took it easy and did not exceed 6000 rpm. The AFR's were sometimes down to 10 and just about off the scale. There was a yellow flag then a red and I think it was the Porsche 911 that left the track. The event was called off shortly afterwards. We are off to Marulan next week for a tuning day as long as it's dry!
 
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