Re: TWiR 1986 S3 TWR
Posted: Mon Jul 08, 2019 5:09 pm
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TWiR 1986 S3 TWR
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Re: TWiR 1986 S3 TWR
Posted: Wed Jul 10, 2019 7:49 pm
That is a very cool setup bro! Nice work on getting it all done aye. Looks awesome in person.
Re: TWiR 1986 S3 TWR
Posted: Wed Jul 10, 2019 9:50 pm
I'm just chasing a couple of minor things. I think there's a vac leak somewhere so I'll need a session with some carb cleaner being directed at various points. And then balancing the two carbs up. There's lots of helpful you tube vids on how to do that. And then it's off to the dyno for real world testing.
It's quite a nice setup, very compact. In fact, I believe your turbo is probably larger
It's quite a nice setup, very compact. In fact, I believe your turbo is probably larger
Re: TWiR 1986 S3 TWR
Posted: Wed Jul 10, 2019 9:53 pm
I used to use something similar to this when i used to restore Spitfires to balance their twin Su's
https://www.ebay.co.uk/itm/STE-Carburet ... SwjXNaW3~j
https://www.ebay.co.uk/itm/STE-Carburet ... SwjXNaW3~j
Re: TWiR 1986 S3 TWR
Posted: Sat Aug 17, 2019 1:11 am
Retro boots back on for RRG 2019. These have not been on the car for a couple of years. Long story short, a couple of local tire fitting establishments couldn't get the wheels to balance properly so they laid the blame (squarely) 
on the lack of roundness in the wheel department. Wheel straightening machine says otherwise. The computer actually did say No.
Moral. Make sure that your tire fitter has talent! Unashamed plug for talented tire fitters here https://www.eghamtyres.co.uk/Testimonial?page=1
on the lack of roundness in the wheel department. Wheel straightening machine says otherwise. The computer actually did say No. Moral. Make sure that your tire fitter has talent! Unashamed plug for talented tire fitters here https://www.eghamtyres.co.uk/Testimonial?page=1
Re: TWiR 1986 S3 TWR
Posted: Sat Aug 17, 2019 7:04 pm
I went with the Gunson option in the end Ian, only because it was cheaper ... under £20 delivered. Does the same job but not nearly as impressive as that synchrometer. https://www.ebay.co.uk/itm/Gunson-Carba ... SwrhlXTsXCian65 wrote: ↑Wed Jul 10, 2019 9:53 pm I used to use something similar to this when i used to restore Spitfires to balance their twin Su's
https://www.ebay.co.uk/itm/STE-Carburet ... SwjXNaW3~j
Re: TWiR 1986 S3 TWR
Posted: Sat Aug 17, 2019 8:20 pm
what size wheels / tyres are they Dave?KiwiDave wrote: ↑Sat Aug 17, 2019 1:11 am Retro boots back on for RRG 2019. These have not been on the car for a couple of years. Long story short, a couple of local tire fitting establishments couldn't get the wheels to balance properly so they laid the blame (squarely)
Moral. Make sure that your tire fitter has talent! Unashamed plug for talented tire fitters here https://www.eghamtyres.co.uk/Testimonial?page=1
Re: TWiR 1986 S3 TWR
Posted: Sat Aug 17, 2019 9:14 pm
It does look good on the gold wheels Dave.
I’m glad you got it sorted.
I’m glad you got it sorted.
Re: TWiR 1986 S3 TWR
Posted: Sat Aug 17, 2019 9:52 pm
Re: TWiR 1986 S3 TWR
Posted: Tue Dec 10, 2019 12:21 am
Today I have mostly been doing ....
Visiting the most excellent and helpful people at Northampton Motorsport. Recommended to me by colleagues who know a thing or two. Just wanted to get the twin SU setup sorted and make sure that it was actually working properly.
And there was none of this sitting in a waiting room whilst they did their stuff (although it is a fine waiting room so far as waiting rooms go, with nice carb displays, magazines galore and a hot drinks machine). I got to watch and talk thru the whole process and learnt a bunch of stuff.
These guys are really clued up and hands on. Even down to adjusting the pedal stop for more travel. Best bit was seeing the carb working in real time on the car with the filters removed so the piston movement and fuel misting was visible. A lot of forces at work in that pocess!
Most surprising was the end result and proof that horsepower is only part of the equation. There's a huge increase in low end throttle response, noticeably quicker throttle response and when you bury the load pedal, it just keeps giving. all the way to 8000 rpm in 4th, no hesitation, no stumbling.And thats on ordinary NGK plug wires and very old school single electrode plugs.
The engine has more torque and absolutely loves it but the overall BHP increase is surprisingly nominal considering the performance gain. I can see why the SU carb was a smart RX upgrade in period.
Fourth gear pull. Noise alert https://youtu.be/yVzCsZAxIQQ
Overall, the SU is like a Berocca for your rotary. It really wakes the car up and it's not like it was all that sleepy to begin with. It's kinda more energised, frantic. There's probably a couple of minor adjustments still to be made but it appears that I accidentally got the mixture and carb balance almost spot on just by ear and that's only 'cos I was pressed for time and freezing my bits off last week swapping carbs over again.
All in all, time well spent today.
Visiting the most excellent and helpful people at Northampton Motorsport. Recommended to me by colleagues who know a thing or two. Just wanted to get the twin SU setup sorted and make sure that it was actually working properly.
And there was none of this sitting in a waiting room whilst they did their stuff (although it is a fine waiting room so far as waiting rooms go, with nice carb displays, magazines galore and a hot drinks machine). I got to watch and talk thru the whole process and learnt a bunch of stuff.
These guys are really clued up and hands on. Even down to adjusting the pedal stop for more travel. Best bit was seeing the carb working in real time on the car with the filters removed so the piston movement and fuel misting was visible. A lot of forces at work in that pocess!
Most surprising was the end result and proof that horsepower is only part of the equation. There's a huge increase in low end throttle response, noticeably quicker throttle response and when you bury the load pedal, it just keeps giving. all the way to 8000 rpm in 4th, no hesitation, no stumbling.And thats on ordinary NGK plug wires and very old school single electrode plugs.
The engine has more torque and absolutely loves it but the overall BHP increase is surprisingly nominal considering the performance gain. I can see why the SU carb was a smart RX upgrade in period.
Fourth gear pull. Noise alert https://youtu.be/yVzCsZAxIQQ
Overall, the SU is like a Berocca for your rotary. It really wakes the car up and it's not like it was all that sleepy to begin with. It's kinda more energised, frantic. There's probably a couple of minor adjustments still to be made but it appears that I accidentally got the mixture and carb balance almost spot on just by ear and that's only 'cos I was pressed for time and freezing my bits off last week swapping carbs over again.
All in all, time well spent today.