Stringing alignment
Discussion
While at the Revival and also my daughters racing, I have seen front running racers use poles with grooves in set up at the front and rear of the car to create two parallel strings (fishing line), from which you measure in to check toe settings.
My kit car is in reality an MX5 set up so I set it up in this way.
For camber angles I use an accurate square and a very true spirit level and have initially set 1 deg neg all round but think 2 might be better on the front.
The car drives really well and even on bumpy corners sticks down without being twitchy.
My tyres are 225x35x17 and as such not really a good choice for a Lotus 7 type car.
Does anybody on here mess with the geo?
I got it wrong some years ago while sprinting at Goodwood and put my TR5 up on its side after a scary spin at 120 mph! All that because it had a touch of positive camber at the back on braking. That is why I know how important it is.
My kit car is in reality an MX5 set up so I set it up in this way.
For camber angles I use an accurate square and a very true spirit level and have initially set 1 deg neg all round but think 2 might be better on the front.
The car drives really well and even on bumpy corners sticks down without being twitchy.
My tyres are 225x35x17 and as such not really a good choice for a Lotus 7 type car.
Does anybody on here mess with the geo?
I got it wrong some years ago while sprinting at Goodwood and put my TR5 up on its side after a scary spin at 120 mph! All that because it had a touch of positive camber at the back on braking. That is why I know how important it is.
I've seen it done and experience skilled technicians can get it all very accurate doing it that way. It's handy being able to do that as a racing team as you can tweak setting at a race track.
However, it does take a lot of skill and experience, which most garages don't have, and I wouldn't trust the vast majority of grease monkeys to get it right. I certainly wouldn't trust myself to get it right before heading out on track! It is a skill that would be good to have though.
Maybe a good starting point would be to get a full laser alignment done then measure it up using the string and see if you can get the same readings...
However, it does take a lot of skill and experience, which most garages don't have, and I wouldn't trust the vast majority of grease monkeys to get it right. I certainly wouldn't trust myself to get it right before heading out on track! It is a skill that would be good to have though.
Maybe a good starting point would be to get a full laser alignment done then measure it up using the string and see if you can get the same readings...
I've used it on my kit with some success.
Adjusting toe-in/out is fairly simples with the string method once you get your head around it.
Lots on youtube to show how it's done.
I bought flourescent fishing line (interestingly the guy in the local tackle shop knew what I was going to use it for saying "there's a car company in Woking who buy this from me...").
You can use wood for end poles but I preferred 25mmSST left over from the build, four axle stands, a set of vernier calipers, a flat floor and you're in business.
Camber however is another kettle of fish - DIY camber guages are possible using a quadrant piece of ply or MDF and attached plumb line.
Spirit level type camber guages IMO aren't accurate enough.
Having had the Eunos set up at WIM I'd agree with Lazza.
Pay for a professional set-up then use your DIY methods to establish a base for future adjustments.
HTH.
Cheers, Pewe.
Adjusting toe-in/out is fairly simples with the string method once you get your head around it.
Lots on youtube to show how it's done.
I bought flourescent fishing line (interestingly the guy in the local tackle shop knew what I was going to use it for saying "there's a car company in Woking who buy this from me...").
You can use wood for end poles but I preferred 25mmSST left over from the build, four axle stands, a set of vernier calipers, a flat floor and you're in business.
Camber however is another kettle of fish - DIY camber guages are possible using a quadrant piece of ply or MDF and attached plumb line.
Spirit level type camber guages IMO aren't accurate enough.
Having had the Eunos set up at WIM I'd agree with Lazza.
Pay for a professional set-up then use your DIY methods to establish a base for future adjustments.
HTH.
Cheers, Pewe.
You guys write good sense.
Yes it is true I do not trust a garage with anything but am MOT because I have to!
Some years ago I had a Dolomite Sprint and had the toe set by a garage and it should have been 1.5mm toe in, but on checking after the tyres showed extreme wear on the outside, I found 8mm toe in. Since then I have done it myself using first straight edges and a tape and now a laser.
The last time I usd my track prepped Sprint at Combe 3 years ago the tyres (Yoko 032)were wearing evenly all round.
I am an engineer and measuring goes with the job but the special I have built has no manual so its a bit of suck it and see.
I have gone from a tentative gentle crawl to the IVA centre in April to some fast cornering in stages while monitering what the tyres and car are doing.
This winter its in with an oil cooler and then in the spring start tracking it in earnest.
I will get a temp gauge to see if the tyres are same temp all across.
Those of you who track their cars I would ask if you stick with stock or increase camber.
You can trig the wheel angle provided the garage floor is flat otherwise perhaps a pendulam and string can do it!
Yes it is true I do not trust a garage with anything but am MOT because I have to!
Some years ago I had a Dolomite Sprint and had the toe set by a garage and it should have been 1.5mm toe in, but on checking after the tyres showed extreme wear on the outside, I found 8mm toe in. Since then I have done it myself using first straight edges and a tape and now a laser.
The last time I usd my track prepped Sprint at Combe 3 years ago the tyres (Yoko 032)were wearing evenly all round.
I am an engineer and measuring goes with the job but the special I have built has no manual so its a bit of suck it and see.
I have gone from a tentative gentle crawl to the IVA centre in April to some fast cornering in stages while monitering what the tyres and car are doing.
This winter its in with an oil cooler and then in the spring start tracking it in earnest.
I will get a temp gauge to see if the tyres are same temp all across.
Those of you who track their cars I would ask if you stick with stock or increase camber.
You can trig the wheel angle provided the garage floor is flat otherwise perhaps a pendulam and string can do it!
trackerjack said:
Those of you who track their cars I would ask if you stick with stock or increase camber.
Standard Mazda settings are very conservative! My local tyre place know their stuff and were happy to set it to my requested spec rather than what the book said, so I never bothered trying to do it myself.I don't have an MX5 anymore, but from memory I used to run:
Caster: 4.5° or a bit more if available.
Front Camber: -1.2°
Front Toe: Slight toe-in, I forget how much but pretty close to zero.
Rear Camber: -1.7°
Rear Toe: Can't remember, either zero or slight toe-in.
That was for mostly road use with a few track days and was very well behaved, on 195/50R15 tyres. You could go far more aggressive than that for track use though, be interesting to see what settings others use on track.
Ah ha Gravel Ben that is pretty much what I have done except with the rear toe which I read somewhere that straight or toe out makes for a twitchy response so I have gone for 3mm toe in.
A friend who bought my TR5 and won the Post Historic Champ in it had zero toe at the front, when I drove the car it was weird but fantastic in corners (I know its not a MX5 but there has to be a start point)
I am at Donnington this weekend supporting my daughter where she will race her Boxster so I will chat with her team guru who loves suspension and scorns those who underestimate the value of a good setup.
A friend who bought my TR5 and won the Post Historic Champ in it had zero toe at the front, when I drove the car it was weird but fantastic in corners (I know its not a MX5 but there has to be a start point)
I am at Donnington this weekend supporting my daughter where she will race her Boxster so I will chat with her team guru who loves suspension and scorns those who underestimate the value of a good setup.
Sure is possible. I am an engineer and had level floor, time, good spirit level and a digital vernier. I got it right but got the thrust angle/line wrong (this is the alignment between the axles so car was crabbing) and it wore a set of tyres out somewhere inside the artic circle .. so I had to get tyres and alignment done up there.. and drive 320 miles that day on 50mph roads. So yes you can but for the cost of a tyre why bother. Mind you would still like to have another go!
Would not want to ruin a set of tyres but I reckon it would quickly betray a poor setup.
My initial start point was to line up parallel with the wheel centres which should create the "box" within which you measure.
The chassis was made for a Cyana and is much better quality than the first kit that I built ("Gemini")back in the 90's which had a twisted chassis which never felt right.
What I do like is the fact that despite really bumpy corners it stays on target, I hate cars that feel unstable.
Interestingly I was at a local car park today that had a shiny road surface and many cars squeel their tyres as they turned on it, showing that the tyre was sliding rather than rolling.
Looking forward to daughters racing tomorrow as last time out she was rammed by a Lotus Elise and had to climb up from almost last to 10th overall and set 2nd fastest lap despite being in group 2.
A win outright is possible if she gets a wet race as she loves the rain!
My initial start point was to line up parallel with the wheel centres which should create the "box" within which you measure.
The chassis was made for a Cyana and is much better quality than the first kit that I built ("Gemini")back in the 90's which had a twisted chassis which never felt right.
What I do like is the fact that despite really bumpy corners it stays on target, I hate cars that feel unstable.
Interestingly I was at a local car park today that had a shiny road surface and many cars squeel their tyres as they turned on it, showing that the tyre was sliding rather than rolling.
Looking forward to daughters racing tomorrow as last time out she was rammed by a Lotus Elise and had to climb up from almost last to 10th overall and set 2nd fastest lap despite being in group 2.
A win outright is possible if she gets a wet race as she loves the rain!
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