K tec Coilovers

[Garysp2]

anyone fitted the Ktec coil overs?
they look a good quality set and a good price.

KTR/Spax Clio 3RS 197 | Early 200 RSX 750MC Race Coilover Kit - V2

Developed on our KTR 197 race car throughout the 2021 season, this complete coilover kit is a must have for track and race use. One of few kits with a true coilover rear and two-way adjustable shocks for a fraction of the price of the other alternatives. Features - 2 Way Adjustable - adjustable...

www.k-tecracing.com

 

[tcw]

I've got GAZ Golds on mine. 400lb front, 300lb rear - very happy with them.

 

[suj]

To answer your question about the KTEC Spax coilovers, I've never seen anyone on here or FB groups run them, but they're pretty new so probably the reason why, they look decent enough for the money being 2-ways, but then they lack adjustable front top mounts, so a good set of PMS ones are gonna be an extra £350ish, so you're then nearly into AST prices....

 

[Garysp2]

I've got GAZ Golds on mine. 400lb front, 300lb rear - very happy with them.

done a bit of research yesterday on the Gaz golds, they look very impressive and a good price.
giving them a call tomorrow ro discuss options

 

[suj]

If you're looking at Gaz Gold's, speak to Matt (@R27WTF ) @ Supreme Motorsport, he can sort you out, also they might have Black Friday deals

 

[Big Ben]

If you are getting Gaz Golds you can spec spring rates to suit what the car is used for either road or track etc. My 197 has 625 front and 325 rear. It’s tolerable on road and good on track.

 

[bedoef]

If you are getting Gaz Golds you can spec spring rates to suit what the car is used for either road or track etc. My 197 has 625 front and 325 rear. It’s tolerable on road and good on track.

I thought cup cars ran a stiffer rear spring rate - but I see a number of people with custom spring rates go the other way. What's the rationale?

I am curious as I have KW clubsports which I believe are just 430ish square, and I am debating getting custom springs for the rear.

 

[tcw]

I thought cup cars ran a stiffer rear spring rate - but I see a number of people with custom spring rates go the other way. What's the rationale?

I am curious as I have KW clubsports which I believe are just 430ish square, and I am debating getting custom springs for the rear.

This is a huge debate had by many. For what it's worth, I think the KW Clubsport are running 70 Nm/mm front and 80 Nm/mm rear from my research. The main thing to remember here is they are using an inboard spring (rather than a full coilover) meaning that, accounting for the motion ratio it works out approximately 50 Nm/mm. I think anyway... . This explains my rationale for going for a 400lb/300lb setup with the GAZ golds, acknowledging that many actually go for much much stiffer fronts. The cup racers, again from what I could see appear to run a similar stiffness front spring with a much stiffer rear spring, I never quite managed to get any solid confirmation on the rear rates but the numbers I could find pointed to a 750lb or so spring...

I've done quite a bit of research in this area, although I barely understand the numbers and am far from an expert I am happy to talk.

 

[J90RDN]

I've got set of cup racer springs here but the trouble is I can't see ANY markings to suggest spring rates . They will be replacing a set of KW V2's, which have been used solely on track and have been utterly brilliant.

 

[Big Ben]

I thought cup cars ran a stiffer rear spring rate - but I see a number of people with custom spring rates go the other way. What's the rationale?

I am curious as I have KW clubsports which I believe are just 430ish square, and I am debating getting custom springs for the rear.

I’ve had mine a few years and spoke direct to Gaz when ordering. A friend was also running 700f and 400r at the time on his dedicated track car so I just followed advice. The car is very neutral possibly leaning slightly to an oversteer. I positively hate understeer and this setup has eliminated this.
In the last year or so a few people on Facebook seem to have reinvented things and go massively the other way in rear much stiffer than front. Even to the extent of mimicking those of us with a setup like mine! Maybe they want the rear sliding about to pretend they’re in a RWD or so they can get photos for the gram who knows.
Id not be confident of saying Gaz spring rates should be compared to KW or BC for example as build and fitment will vary.
If you see a car in a “tripod” pose on a trackday photo what does it tell you?
Front springs not stiff enough

 

[RSRowe]

I think mine are slightly lighter than yours, and at no point have I thought I need stiffer springs

Someone with a big brain should work out the motion ratios. That would be the definitive option. It’s just difficult cus there’s so many variables

 

[LiamP]

It’s odd that the gaz setup seems to work well with those rates, I had 80/80 on AST’s and have since bumped the rear up to 100 and it’s now perfect. Was really struggling with getting any rotation on slow corners when both at 80 so can’t imagine what it would be like with a softer front. Lifting a tyre is what helps with rotation, you can feel it happening and it’s great.

I assume the design of the coilover comes into it as AST’s are inverted.

 

[Sean197]

I think the motion ratio is around 2:1 for an inboard spring compared to a true rear coilover setup because of the way the original spring position works as a lever and with a true rear coilover the force works directly on the wheel. So, for example, @Big Ben to replicate your rear spring rate using a kit with inboard rear springs would take a 650lb rear spring as opposed to your 325lb true rear coilover spring.
Happy to be corrected though.

 

[tcw]

I found some motion ratios mentioned on one of the Renault docs suggested 0.96 front, 0.9 rear (but the rear is using a full coilover for this calc)

I did some rough measurements and figure the inboard spring motion ratio is about 1.5

 

[tcw]

It is worth also having a little look at what's written here about spring rates: https://www.pure-motorsport.co.uk/pure-motorsport-bilstein-full-coilover-kit-clio-3rs

 

[suj]

It’s odd that the gaz setup seems to work well with those rates, I had 80/80 on AST’s and have since bumped the rear up to 100 and it’s now perfect. Was really struggling with getting any rotation on slow corners when both at 80 so can’t imagine what it would be like with a softer front. Lifting a tyre is what helps with rotation, you can feel it happening and it’s great.

I assume the design of the coilover comes into it as AST’s are inverted.

Inverted and also monotube dampers on ASTs, so totally different setup from Gaz Golds

 

[bedoef]

It’s odd that the gaz setup seems to work well with those rates, I had 80/80 on AST’s and have since bumped the rear up to 100 and it’s now perfect. Was really struggling with getting any rotation on slow corners when both at 80 so can’t imagine what it would be like with a softer front. Lifting a tyre is what helps with rotation, you can feel it happening and it’s great.

I assume the design of the coilover comes into it as AST’s are inverted.

This is what I thought - kicking up a rear wheel = maximum turn in. But for the guys running stiffer fronts, I wonder how their lap times compare to the opposite setup on the same track?

 

[LiamP]

This is what I thought - kicking up a rear wheel = maximum turn in. But for the guys running stiffer fronts, I wonder how their lap times compare to the opposite setup on the same track?

There is a guy who races knockhill a lot did this but not sure what the outcome was.

 

[RSRowe]

Regardless of the outcome of anything, it’s always an improvement cus people will never admit they’ve wasted their time/money

 

[LiamP]

Regardless of the outcome of anything, it’s always an improvement cus people will never admit they’ve wasted their time/money

Yeah agreed, it seems coilover design is a big factor in this which I find odd as you would think the optimum stiffness front to rear would be consistent and the damping would be different.

Although it will come down to driver preference as my setup is now very ‘lively’ and regularly catches me out so can’t imagine what a cup racer would be like to drive!