Help choosing new suspension

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Christof
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Name: Christof
Location: Cambridgeshire

Help choosing new suspension

Postby Christof » Tue Oct 31, 2017 10:53 am

I'm hoping y'all can help me chose new suspension, currently have a Frankenstein set-up that is too low and hard

Striker X-flow, 13" rims 185tyres, english axle, in-board fronts. Will be 80-90% road use, possibly some track.

Just need basic level, not looking for super-duper multi adjustable.

Many thanks

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pigeondave
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Name: David Malenczak
Location: Brighton

Re: Help choosing new suspension

Postby pigeondave » Tue Oct 31, 2017 2:29 pm

single adjustable protechs
http://www.protechshocks.co.uk/

thats what ive got.

some will tell you to buy them through procomp http://www.procomp.co.uk/, others will say go straight to protech. Its up to you.

There are other makes about, but everyone seems to use protechs

Someone will be along to give you closed and open lengths and whether you need to have to extended eyes on the back ones

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adithorp
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Name: adrian thorp
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Re: Help choosing new suspension

Postby adithorp » Wed Nov 01, 2017 2:42 pm

What Dave said.

Length wise, if you remove the front shocks and use a jack to lower wheels to the ground and thechassis to the ride height you want; normally you'd be looking at the height that the lower wishbone pivots points (centre of balljoint to inner mounting bolt) are horizontal. Then measure the distance between the shock mounts. Chose a shock length were the travel wi'll allow about 2/3rd bump and 1/3rd droop from that height. Repeat for the rear.

Remember, the advertised length of a shock doesn't usually take into account the bump stop; So an 8"closed/12"open shock probably has a usable travel of 9-12"

micha
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Name: Micha mertens

Re: Help choosing new suspension

Postby micha » Thu Nov 02, 2017 9:11 pm

all my (live-axle, x/flow powered) sylvas had 12.5 inch shocks around with 130lbs coils on all 4 corners

sylva´s are usally set rather soft, especially on rear

typre pressure around 1,2bar all around, or 1.0 bar rears, 1,2bar fronts..depending on tyre brand
1985/60r13

i would always vote for protech

Christof
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Name: Christof
Location: Cambridgeshire

Re: Help choosing new suspension

Postby Christof » Fri Nov 03, 2017 6:33 pm

thanks peeps

took her out for a jaunt today and after 50 miles felt like I'd been 12 rounds with Mike Tyson, would have fallen out if I hadn't been strapped in! Still fun though! :D

Anyone else have recommendation for spring rates?

Google seems to imply 220lb/180lb upwards for track and perhaps 180/130or140 for road. Halfway house possibly 200/160.

130 on the front seems a bit soft? Bike engined?

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adithorp
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Name: adrian thorp
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Re: Help choosing new suspension

Postby adithorp » Fri Nov 03, 2017 9:31 pm

Think Jeremy originally recomended 160-180 front and 130-140 rear. However many have tried harder than that and prefered it. Going to between 200-220 front and 160-180 rear.

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pigeondave
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Name: David Malenczak
Location: Brighton

Re: Help choosing new suspension

Postby pigeondave » Mon Nov 06, 2017 2:35 pm

Im not sure if the rocker ratios are different on the striker than the Fury. I have a zetec Fury running 220 on the front and 180 on the rears.

Depending on how far you want to take things this guy has done a spreadsheet to give you a ball park figure for the spring rates. All you have to do is pump in the data and then have the balls to act on it (i dont have the balls to do it)
http://www.neileverett.madasafish.com/m ... ampers.htm

the mods menu is a great read in itself.

Also have you tried speaking to Raw for some advice ?

Christof
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Joined: Thu Jan 05, 2017 12:51 pm
Name: Christof
Location: Cambridgeshire

Re: Help choosing new suspension

Postby Christof » Fri Nov 10, 2017 9:10 pm

thanks for responses
raw say-
For mainly road use I would go for 180lb front springs and 150 or 130 rear. If the roads around your area are particularly rough like ours I would go for the softer rears. Start with the shocks adjustment fully off and then adjust to your liking after first drive.
Ride height from the chassis rail under the rad to the floor would be 120-130mm or as close to as possible. Try to aim for the bottom wishbone to be angled slightly down at the wheel end. Then set the rear ride height from the chassis rail under the seat back to the floor to the front ride height plus 15-20mm. Set the ride heights with someone or something in the driver’s seat approx the same weight as you.
and also-
Over the years the live axle cars have varied a bit so you would need to remove the shocks from the car, take the springs off and then measure the open and closed lengths. Front and rear are probably different. You can then measure the length of the springs which are probably 8 or 9 inch.
Spring diameter will be either 1.9 or 2.25 inches


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