Sp12's - Tyre Pressures?
Discussion
Hi folks,
Have just fitted a set of SP12's to my Griff 7*17" front, 8*18" rear - on Toyo Proxes T1-Rs. Not had a chance to go test it properly yet (flippin' rain in Scotland!!!) and wondered if anybody else has them and had time to play around with the tyre pressures? Came with the usual 35+psi in them so have dropped it 26psi front, 28psi rear to start with (figured the lower profile would like a few pounds more than the standard tyres)?
Cheers,
Have just fitted a set of SP12's to my Griff 7*17" front, 8*18" rear - on Toyo Proxes T1-Rs. Not had a chance to go test it properly yet (flippin' rain in Scotland!!!) and wondered if anybody else has them and had time to play around with the tyre pressures? Came with the usual 35+psi in them so have dropped it 26psi front, 28psi rear to start with (figured the lower profile would like a few pounds more than the standard tyres)?
Cheers,
Thanks guys,
Mine came direct from SP's supplier due to me being in Scotland and the F1 Grand Prix causing some headaches for Matt at SP. However, they were over inflated as is usual from non-TVR familiar suppliers. Wasn't sure what best to use so thought I'd ask to see if anyone had tried various settings.
I can maybe try dropping down a few lbs all round then.
Mine came direct from SP's supplier due to me being in Scotland and the F1 Grand Prix causing some headaches for Matt at SP. However, they were over inflated as is usual from non-TVR familiar suppliers. Wasn't sure what best to use so thought I'd ask to see if anyone had tried various settings.
I can maybe try dropping down a few lbs all round then.
24 front, 26 rear. But, as posted before, I'm not happy with the tyres. At these low pressures they do like to walk about the rim! I frequently bang the rear rims on the tarmac when cornering hard with a bit of power down. Along comes a little bump in the road and....BANG. Seriously not impressed. Also feel the effects of the soft tyrewall when cornering generally. 245/35/18 too low profile for this tyre at these pressures IMHO
It is a love hate relationship though. The grip is great.
My point/question is it is tempting to pump up the pressure a little to help support the tyre...?
It is a love hate relationship though. The grip is great.
My point/question is it is tempting to pump up the pressure a little to help support the tyre...?
Chimjunkie said:
24 front, 26 rear. But, as posted before, I'm not happy with the tyres. At these low pressures they do like to walk about the rim! I frequently bang the rear rims on the tarmac when cornering hard with a bit of power down. Along comes a little bump in the road and....BANG. Seriously not impressed. Also feel the effects of the soft tyrewall when cornering generally. 245/35/18 too low profile for this tyre at these pressures IMHO
It is a love hate relationship though. The grip is great.
My point/question is it is tempting to pump up the pressure a little to help support the tyre...?
Now, I specifically asked whether this was likely to be an issue and was assured it wouldn't happen... concerned now as I do hoof it hard on bumpy twisties It is a love hate relationship though. The grip is great.
My point/question is it is tempting to pump up the pressure a little to help support the tyre...?
Hi,
I have the SP 12's ready to fit and have on order the Bridgestone RE050 which are meant to have very good side wall stability. They are designed for very high performance cars, especially driving in warm/tropical climates, they do not recommend use in near or freezing conditions. Only draw back, production to order so 3 months (1 month to go) lead time, as this product is not kept on the shelf. Should have the Griff with me around that time. Take a look at Bridgestone website, SO2's were great, SO3's not so, but they assure me RE050's are, we will see?
I have the SP 12's ready to fit and have on order the Bridgestone RE050 which are meant to have very good side wall stability. They are designed for very high performance cars, especially driving in warm/tropical climates, they do not recommend use in near or freezing conditions. Only draw back, production to order so 3 months (1 month to go) lead time, as this product is not kept on the shelf. Should have the Griff with me around that time. Take a look at Bridgestone website, SO2's were great, SO3's not so, but they assure me RE050's are, we will see?
GAARD said:
Hi,
I have the SP 12's ready to fit and have on order the Bridgestone RE050 which are meant to have very good side wall stability. They are designed for very high performance cars, especially driving in warm/tropical climates, they do not recommend use in near or freezing conditions. Only draw back, production to order so 3 months (1 month to go) lead time, as this product is not kept on the shelf. Should have the Griff with me around that time. Take a look at Bridgestone website, SO2's were great, SO3's not so, but they assure me RE050's are, we will see?
Hello Andy - I didnt recognise you from your login I have the SP 12's ready to fit and have on order the Bridgestone RE050 which are meant to have very good side wall stability. They are designed for very high performance cars, especially driving in warm/tropical climates, they do not recommend use in near or freezing conditions. Only draw back, production to order so 3 months (1 month to go) lead time, as this product is not kept on the shelf. Should have the Griff with me around that time. Take a look at Bridgestone website, SO2's were great, SO3's not so, but they assure me RE050's are, we will see?
Its alright for you in the Phillipines with your "driving in warm/tropical climates"
- we have part of that at the moment i.e. monsoons 
When is your Griff back on the road??
Any pics for us?
Are you coming over to Rockingham? If so will you be around for the Growl?
Graham
Hi Graham,
Giff was delivered to Clives house in Singapore last Tuesday, he was on the mobile to me and said it looked as we sailors say f$%#^ stunning. He is going to fit the light covers and then off to me here in Manila. Clive is away for a few weeks now but once he gets back we can start talking exact dates.
sad I am not going to miss Rockingham but may make the Growl I am working on trying to coincide a trip to the UK.
ah yes GAARD is Manx for a coming violent thunderstorm, if you have heard my Griff with the Zertec 4 pipe sports exhaust you would know why!!!!
Andy
Giff was delivered to Clives house in Singapore last Tuesday, he was on the mobile to me and said it looked as we sailors say f$%#^ stunning. He is going to fit the light covers and then off to me here in Manila. Clive is away for a few weeks now but once he gets back we can start talking exact dates.
sad I am not going to miss Rockingham but may make the Growl I am working on trying to coincide a trip to the UK.
ah yes GAARD is Manx for a coming violent thunderstorm, if you have heard my Griff with the Zertec 4 pipe sports exhaust you would know why!!!!
Andy
GAARD said:
Hi Graham,
Giff was delivered to Clives house in Singapore last Tuesday, he was on the mobile to me and said it looked as we sailors say f$%#^ stunning. He is going to fit the light covers and then off to me here in Manila. Clive is away for a few weeks now but once he gets back we can start talking exact dates.
sad I am not going to miss Rockingham but may make the Growl I am working on trying to coincide a trip to the UK.
ah yes GAARD is Manx for a coming violent thunderstorm, if you have heard my Griff with the Zertec 4 pipe sports exhaust you would know why!!!!
Andy
Andy - it would be great to meet you at the Growl if you can make itGiff was delivered to Clives house in Singapore last Tuesday, he was on the mobile to me and said it looked as we sailors say f$%#^ stunning. He is going to fit the light covers and then off to me here in Manila. Clive is away for a few weeks now but once he gets back we can start talking exact dates.
sad I am not going to miss Rockingham but may make the Growl I am working on trying to coincide a trip to the UK.
ah yes GAARD is Manx for a coming violent thunderstorm, if you have heard my Griff with the Zertec 4 pipe sports exhaust you would know why!!!!
Andy
Make sure to say hello....
its like listening to girls talking about hand bags and shoes Hi Guys,
I still have to fit the SP12's when the car arrives, I understand a slight job is required on the split pin on the brakes and to the centre plastic cap, anyone done this themselves or did Matt do this for you all. If you did do it yourself anyone take any photos?
Would be much appreciated, kindest regards
Andy
I still have to fit the SP12's when the car arrives, I understand a slight job is required on the split pin on the brakes and to the centre plastic cap, anyone done this themselves or did Matt do this for you all. If you did do it yourself anyone take any photos?
Would be much appreciated, kindest regards
Andy
Hi Andy,
Yeah, I did mine myself although only after a few calls to Matt Lee at SP. It's not that difficult once you know what's needed...just your typical TVR with nothing being quite 'off the shelf'! More hassle than hard to be honest.
Front wheels are a doddle and go straight on without anything needing done. Do these first and you'll be enthusiastic enough for the elbow grease needed for the rear!
There's two small things you need to do for the rear and these are purely for the centre caps to fit...the wheels go on perfect without any mods!!!
- The first is that the axel spline from the hub sticks out a bit too far to allow the cap to clip onto the wheel (you'll see when you try). The big copper coloured nut that holds the wheel bearing / hub in place is the perfect distance so you have to cut the excess spline off so it's flush to the nut. The cap face then sits tight up against this but is enough to clip onto the wheel! Easy job but hard work with a hacksaw...was advised not to use a power tool in case it heated and warped anything.
- Second, due to the size of that centre nut, you have to buff 6 small notches into the inner side of the cap to match the 6 pointed edges of the nut. Matt was good enough to supply the caps already done as it was hard to understand on the phone when I was at work.
I'm not sure how to post a pic on here but can email you one if you want. It's obvious once you see it!
Yeah, I did mine myself although only after a few calls to Matt Lee at SP. It's not that difficult once you know what's needed...just your typical TVR with nothing being quite 'off the shelf'! More hassle than hard to be honest.
Front wheels are a doddle and go straight on without anything needing done. Do these first and you'll be enthusiastic enough for the elbow grease needed for the rear!
There's two small things you need to do for the rear and these are purely for the centre caps to fit...the wheels go on perfect without any mods!!!
- The first is that the axel spline from the hub sticks out a bit too far to allow the cap to clip onto the wheel (you'll see when you try). The big copper coloured nut that holds the wheel bearing / hub in place is the perfect distance so you have to cut the excess spline off so it's flush to the nut. The cap face then sits tight up against this but is enough to clip onto the wheel! Easy job but hard work with a hacksaw...was advised not to use a power tool in case it heated and warped anything.
- Second, due to the size of that centre nut, you have to buff 6 small notches into the inner side of the cap to match the 6 pointed edges of the nut. Matt was good enough to supply the caps already done as it was hard to understand on the phone when I was at work.
I'm not sure how to post a pic on here but can email you one if you want. It's obvious once you see it!
Wot they said on the hacksawing bit.... the material is surprisingly easy to cut and dress with a file to finish off... when notching the centre caps, dont be too enthusiastic as the inner ring that's being reduced will drop out if it loses its tension and only a tickle needs to come out.
Just as an aside, Teds round resin 'smiley' badges are exactly the right size for the centres... they look a treat when done
Just as an aside, Teds round resin 'smiley' badges are exactly the right size for the centres... they look a treat when done
Oh. That's quite a big difference. I suppose the pressure is not just car (weight) dependent. It must be dependent upon structure of the tyre? The original factory fitted tyres are much stiffer construction and therefore less pressure required at a given car weight to maintain shape. Would be interesting to hear from anyone who really understands tyres...
I assume this figure is for 17"/18" rims and not the 15"/16" rims?
Any idea how much consideration toyo put into this figure?
I assume this figure is for 17"/18" rims and not the 15"/16" rims?
Any idea how much consideration toyo put into this figure?
Chimjunkie said:
I assume this figure is for 17"/18" rims and not the 15"/16" rims?
Any idea how much consideration toyo put into this figure?
It specifically referenced 215 40 17 Fr and 245 35 18 Rr T1Rs and the full detail of the car and intended use was given (fast road, bumpy twisties). Anyone know what the TVR recommended pressures were on 18" clad Tuscans (say) with similar profiles fitted? Just as a rough comparison.Any idea how much consideration toyo put into this figure?
Found this quote:
"My Tuscan hand book clearly states 28 psi front and rear going up to 31 for sustained high speed, track days or fully laden. I've been using these values on the car since new with no problems or odd tyre wear."
Lots of variation in response to this in the thread though.
"My Tuscan hand book clearly states 28 psi front and rear going up to 31 for sustained high speed, track days or fully laden. I've been using these values on the car since new with no problems or odd tyre wear."
Lots of variation in response to this in the thread though.
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