Re: S4 Starter motor in S3
Posted: Tue Jun 10, 2025 4:23 pm
It's soooooo clean in that engine bay - it's unreal 
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S4 Starter motor in S3
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Re: S4 Starter motor in S3
Posted: Tue Jun 10, 2025 7:26 pm
Yeah mint bro
Re: S4 Starter motor in S3
Posted: Tue Jun 10, 2025 7:31 pm
Thanks chaps! It’s a fair few hours of elbow grease I tell you..
It won’t last sadly
It won’t last sadly
Re: S4 Starter motor in S3
Posted: Wed Jun 11, 2025 12:12 am
Looking great vic, I'm very jealous of the aircon!
Talking belts, I much prefer the shorty belt set up to dual sheave pulley on the alternator. I've shredded/thrown belts and been stranded by the stock and dual belt set up, and just generally noticed one belt never stays tensioned of the two and had some slip. Shorty belt set up has been working perfectly for thousands of miles on my street car, still running a clutch fan which combined with dual belts always had slip. Also running shorty belt on my race car with e fan, but I still shredded a belt on before, now several trackdays and races and about 500 road miles on that, no issues there either.
Talking belts, I much prefer the shorty belt set up to dual sheave pulley on the alternator. I've shredded/thrown belts and been stranded by the stock and dual belt set up, and just generally noticed one belt never stays tensioned of the two and had some slip. Shorty belt set up has been working perfectly for thousands of miles on my street car, still running a clutch fan which combined with dual belts always had slip. Also running shorty belt on my race car with e fan, but I still shredded a belt on before, now several trackdays and races and about 500 road miles on that, no issues there either.
gt_james wrote: ↑Wed Jan 31, 2024 3:04 pm I made a post on facebook, but will put the info here too.
For the belt that goes around the E shaft, Water pump and alternator, with stock pulleys, I used a 11x800 Dayco brand belt. 11A0800C P/N.
If you have removed the air pump, the alternator belt will slip on the water pump.
You can get a dual groove alternator pulley, but they still slip, especially under load as the side of the belt that rubs the water pump goes slack.
The other option is you can run a short belt just around the E shaft and water pump pulleys.
If you have stock pulleys, the belt you want is 10x550.
If you have a racing beat main pulley like I do, then after trying a few belts, the length you want is 10x483. The belt I have is a continental.
Yes "11" width for one belt, and "10" width on the other one. They are both a good fit.
So you will still have 2 belts, one short, one long, on the stock pulleys.
Re: S4 Starter motor in S3
Posted: Thu Jun 12, 2025 9:54 am
gt_james wrote: ↑Wed Jun 11, 2025 12:12 am Looking great vic, I'm very jealous of the aircon!
Talking belts, I much prefer the shorty belt set up to dual sheave pulley on the alternator. I've shredded/thrown belts and been stranded by the stock and dual belt set up, and just generally noticed one belt never stays tensioned of the two and had some slip. Shorty belt set up has been working perfectly for thousands of miles on my street car, still running a clutch fan which combined with dual belts always had slip. Also running shorty belt on my race car with e fan, but I still shredded a belt on before, now several trackdays and races and about 500 road miles on that, no issues there either.
gt_james wrote: ↑Wed Jan 31, 2024 3:04 pm I made a post on facebook, but will put the info here too.
For the belt that goes around the E shaft, Water pump and alternator, with stock pulleys, I used a 11x800 Dayco brand belt. 11A0800C P/N.
If you have removed the air pump, the alternator belt will slip on the water pump.
You can get a dual groove alternator pulley, but they still slip, especially under load as the side of the belt that rubs the water pump goes slack.
The other option is you can run a short belt just around the E shaft and water pump pulleys.
If you have stock pulleys, the belt you want is 10x550.
If you have a racing beat main pulley like I do, then after trying a few belts, the length you want is 10x483. The belt I have is a continental.
Yes "11" width for one belt, and "10" width on the other one. They are both a good fit.
So you will still have 2 belts, one short, one long, on the stock pulleys.
The aircon install is pretty straight forward to be honest.. you can use a bracket from the US or Japanese model.. aircon box from either a Japanese FB or a mk1 MX5 (I have a spare that I bought from Buyee Japan for £20)… I’m making the hoses myself using an aircon rad/condenser from a Porsche (nice and small).. and a universal fit 12v aircon pump .. all you need then is a switch in the cabin to turn it on.
I did actually have one of the small lawn mower belts which worked brilliantly. Iv just gone dual pulley for the new alternator. If I have issues then il either go gilmer or back to a lawn mower belt.. the pulleys were all shot blasted to a rough surface profile prior to painting. So once the paint wears through it should grip nicely