Madabout Kitcars Forum

Madabout Kitcars Forum (
-   Marlin 5exi builds (
-   -   Another EXI on sale (

SDMC001 11th May 2015 15:43

Another EXI on sale

5exi beast 22nd May 2015 18:18

It's mine all mine!
Well that was an interesting drive home! After buying the above eBay car!
Found this forum after google searching Marlin 5exi camber castor settings, prompted by a 130 mile drive home via the Woodhead Pass.........with bottom clenching understeer....are the wheels hovering above the ground? ....steering by will power alone! Got great potential but needs dramatic work.

SDMC001 23rd May 2015 06:48

Welcome to Madabout Beast, you will find looking at some of the older threads there has been issues related to the Marlin being a little tail happy, I used a local company to me who nearly fixed the issue, made the car very drivable.

I am sure now you have introduced yourself onto the site you will get some support and suggestions of where to go for help.

There is a company at Castle Coombe, cant think of the name, sure you someone will provide that info who have done good work on the rear suspension.

Hope you enjoy the car.


5exi beast 23rd May 2015 08:48

Hi Steve
Thanks for the welcome, I have now had a roam around the handling issue postings, and yes it seems a common issue. On the M1 at 60pmh and surface imperfection made the car leap clear of the road, and the wind push me a foot to the left, quite exciting really! :spider:
Cornering right seemed to initiate vague understeer, or the feeling similar to a rouge supermarket trolley! I'm not religious but I did enrol the name of our saviour a few times on the Woodhead pass, as the road dropped off both left and right :amen:
I hope to sort it out, and armed with some basic factory setting I will try my local garage to reset the tracking to factory and go from there!
If I live that long, :yield:

bigrich 23rd May 2015 11:23

Hi Martin,

Welcome to exi ownership....where are you in the country - 'up north?'.

You've found the first challenge! (really like your rims by the way!). This post will be a bit lengthy, but worth reading - trust me (point 6 esp).

I built mine back in 2006 and instantly found some serious handling issues - particularly at the rear. I've since solved these (well solved enough to stop me worrying when I drive!)....but there are other basics you need to check too.

You're running a K series engine setup on the original Mk1 chassis (same as mine) ....I'm assuming tyres are 185/55 R15 or 195/50 R15. Below are some basics in order of simplicity to check /adjust!

(1) Tyre pressures - cold pressures need to be somewhere between 15psi - 18psi all round. I run mine at 15psi front, 17psi rear. If you inflate tyres to the usual car pressures of 28 - 32psi then it will skip around like a mountain goat.

(2) Damper settings - the Gaz adjustable dampers have the setting knob on the damper body. Fully clockwise is maximum, fully anticlockwise is minimum...the difference between the 2 is about 40 'clicks' on mine. I run at between 8 and 13 clicks from zero....i.e. soft. Again, if you set them at the upper range the handling can get skittish.

(3) Ride height / corner weights - try to get the ride heights as even as possible around the car by adjusting the spring platform. I run 130 - 140mm ride height measured from floor to chassis rail. If you can then get the car on scales so you can corner weight it to get the balance spot on.

(4) Spring settings - Marlin seemed to supply all manner of spring heights and stiffness for these cars. Search this forum for spring setup and you will be able to see the different setup's people have tried. In my experience this is one is a bit trial and error....but my car definitely improved for stiffer, longer front springs

(5) Geometry settings....I could never get any baseline settings from marlin (be interested if you have) when I asked, so ended up using Lotus Elise / 340R geometry guidelines (see SELOC for the data). Each wheel needs some negative camber. The toe setting front and rear can also make it handle like a bag of spuds if wrong. I generally set my rear toe in at approx2-3mm overall & my front wheels to parallel.

Beware using standard garage laser alignment.....the chassis and suspension on your car is hand made and probably won't be the same on each side once assembled. This is known as 'setback' in geometry terms. I once had a good local garage set my tracking with gauges and it was worse than when they started because of this setback issue. Either use the DIY fishing line and poles set up (also a link on this forum somewhere for it) or a decent £50+ 4 wheel alignment that measures setback and compensates for it. I use the string method and get reasonable results

(6) This is a critical one - the rear hub assembly on the Mk1 chassis have an inherent design weakness. The toe control link pivots on the top of the hub using a different size ball joint to the wishbone pivot. This means that as the suspension travels up and down the toe control arm actually induces passive steering on the rear hub - and it does this a lot. This is probably the cause of the feeling you had when the car skips around on uneven roads. At speed this can be a real problem and I had a couple of really hairy moments before I fixed this. Marlin have redesigned the rear suspension to eliminate this but this involves new upper wishbones, hub etc.....I created a less intrusive fix by using rose joint type rod ends to get the pivot points at the same height. Again, there is a thread on this forum detailing what I did to solve the issue on mine (usual caveats apply - It worked for me but I cannot take responsibility for your own setup if you choose to adopt this)

(7) Tyres - almost forgot these - dependant on use for the car some 'sticky' tyres can also greatly improve things once you have addressed these other points. I opted for Kumho V70a trackday tyres (road legal) - they are fantastic on my car....R888 etc would probably be great too.

So...if you made it to here you are probably thinking 'OMG!' - but the benefit from sorting these things is really good!

Also - there is a company called Track Developments based at Castle Coombe race circuit. Dave Gallop is the main man there and he has done lots of work on redesigning wishbones and geometry setup for at least 2 5exi's that I know of. He is good and I'm sure would put your car right for a fee. (Depends how much you enjoy tinkering with it yourself :))



5exi beast 23rd May 2015 20:26

Hi Rich (how big)
Sorry about the delayed response, but been working today.
OMG That's what you get when you don't research a car well, and buy with your heart (well eyes at least), I didn't know the car was inherently unstable and needed a redesign, nee remake! Buying with your eyes, not your head!
(not the first time as my ex wife, she was a looker, but poor in the bends, and nearly ended me once or twice, think I'll name her ( the car) Joann!) :amen:
Thanks for the advice , it makes me more determined to 'sort her out' (not the ex!, done that, hence the ex!). Since my scary 140 mile return trip, akin to Alton Towers blindfold I have not dared peer under her cover, but I will start to unfold the beast, and see if I can tame her using your invaluable advice, I feel I have adopted a troubled beast that could enchant or kill me! But I feel like ' the game to tame' has started. How foolish I thought jump in blast off...wheeeeee! More like , ' what the aaaaargh no no phew, plus my brake and accelerator extended pedal covers are so close, you get involuntary bowel movements as you hit the brake ne accelerator entering a bend, the massive oversteer complements a bowel waffling few seconds! This was coming over the Woodhead pass from the M1 (Sheffield) to there I live on the Manchester/Tameside edge of the Peak District. Clenched doesn't describe it, as I was negotiating bends with An M5 up my Jacksie, almost deciding to undertake me on an S bend, as I under steered followed by a shake of the rear in oversteer snap understeer, (am I on castors was my first thought) . The rest of the journey was uneventful, and quiet, and under 50mph, you can only use so much adrenaline in one day!
So tyre pressure, tyres and size, and get a bead on what the heck geometry is going on. The only description I have is that anything above 50mph my steering felt as though the wheels were hardly touching tarmack. Determined to sort it though, so thanks for your invaluable support and information.
I hope to ask you for more advice, and keep you up to date with any progress.
Where a outs are you? We have some awesome roads in the High Peaks, and determined to get it in usable shape for the summer.
Thanks for the invaluable information, hope to keep in touch!:wave:
Going to peer under its cover now, and hope it don't bite!
Many thanks

bigrich 23rd May 2015 21:18

Hi Martin,

The 'Bigrich' username is my height - 2m (6'6" in old money)....and fit in the exi a treat! be honest this is one of the only kit's I can fit comfortably.

I'm in Crewe, not too far away. Happy to help where I can.


5exi beast 23rd May 2015 22:03

NW 5exi
Jeebers 6'6" is big, almost a foot taller than Lil ole me 5'73/4"
I just bought a memory foam seat pad ( booster seat ha ha) as the Marlin seat is v flat and thin, this was my first reaction but will play with tilt as my legs seem to have no under thigh support, like sitting in a bath legs out straight!
I need to get this beast handling well as Iv just had a sit in her, and it is definitely 5exi.
Crewe is Just down the road, so when I get the wheels all pointing in the same direction is will have to meet halfway!
Thanks for the offer of help, much appreciate!

SDMC001 24th May 2015 19:08

Hi Martin

Glad Richard was able to give you some good sound advice, Rich and me have had many a chat in the past regarding various alterations we have made.

I no longer have my Marlin, I sold it several years ago, and to be honest sometimes wonder why I did as when the suspension is set right, or at least as best you can get it, its a great fun car.

I like Rich had a 1600, then updated the engine to the 1800VVC which is a good mod which Rich did later, but don't need to rush into it. Don't know what engine you have, but the 16 is a great fun very free revving which you can normally bury the throttle and think wow that's what its about.

Rich I know has done lots of good work on the suspension, so I am sure with some work will work for you so you can enjoy the car too.

I do have a kit car, as after selling the Marlin did miss the fun factor, I have a Shelsley T2.

By the way height wise, compared to Rich I am a shorty at 6 Foot 2, great car for the taller man, equally my wife at 5 foot enjoyed driving it.

Good luck Steve

5exi beast 24th May 2015 19:48

Hi Steve
Thanks for the welcome. Is the Shelsey T2 from memory 5exi esque in appearance? Or memory fail me?
My kit car past included a Mini Marcos (should have kept), a Gia Deltoid (should have kept, now in Holland), a Tripos R81 (should have kept, now in Italy) and an Excallibur ( glad it went).
Armed with such good advice and clear expertise I hope to get the little darling hopping along, with the 1600 fizzing away behind my head. I have a dyno sheet of 119 bhp, which considering the 1.4 K series puts out 105bh, but for the foreseeable future ( if I have one, current geometry willing) the 1.6 will do!
I also have the 206 halo black lights, but the plastic lense looks berry crazed and would not pass an Mot methinks!
She needs a good clean and servic. The hood is good and the inflatable roof brace is there, with a carry bag. Alloys show slight oxidation and might plastic dip matt black to temp hide as it peels off when a refurbished is due!
Great exhaust note, not too loud but was intrusive with roof on. She has a stereo Cd player but no idea if ironworks or where the speakers could be?! I may replace with some jap digi gauges I have.
I noticed the wishbones were chromed and shocks looked rusty too, so adjustment may be delayed till WD40 kicks in!
Well I hope to peer into the clamshells tomorrow and discover what Iv bought and post a pic or two if the forum allows.
Many thanks

EXI Turbo 24th May 2015 19:54

Hi Martin, I also had the same handling issues you mention.

I had tried the simple things first which improved it slightly e.g. tyre pressures, sticky tyres, ride height etc but it still felt scary above 60mph.

The biggest improvement came when I fitted the rose joint type rod ends as mentioned in rich's posts and help from another member on this forum to adjust the height of the pivot points. I'ts not perfect but was good enough to drive to Le Mans last year for the 24 hr race.

good luck


5exi beast 24th May 2015 20:21

Hi Nick
Thanks for the advice, I will do as you say and start with the TP's, and look at the Yokahamas in detail. Maybe back off the suspension as she feels solid, no wonder it skitters over bumps if she relys on tyre pressure for suspension compliance.
Does the factory acknowledge the 'handling issues?' as you think they might have developed a, handling pack' by now, which would be a good business move! Or diversify into undertaking!
Overall though I'm so glad the issue is so prominent as I thought I had lost my race driver skills, and I'm here to say I only backed off from 70+ oops! To 60mph which seems to be the safe zone halfway home. Thank the Lord I didn't choose the Snake Pass ( which I often do) as these posts would not have occurred. :eusa_boohoo:
Thanks for all your :help: and keep it coming!
Many thanks

5exi beast 25th May 2015 15:26

A good start!
Well chaps, just done the tyre pressures, and 38psi all round!
Could be onto something here!,:faint:

limpabit 26th May 2015 13:18

Hi Martin,

Welcome aboard the 5exi bus!

38PSI!!!!! Will make a big difference to 18PSI!

I did the lazy/easy route and shipped the car off to track developments. I too had the mark1 suspension at the beginning. Alignment setup by Marlin. To be honest, for some reason, did not experience the problems others had. Quite easy go above the legal limit and not want to kill you!

Upgraded to the mark2 setup but had all sorts of problems that was not quite right. So after engine upgrade (and power!), shipped car off to track developments. Totally transformed the car and can throw it about with confidence.

5exi beast 26th May 2015 13:47

+10 PSi
I'm hopeful +10 PSi will transform handling but realistic it won't solve much unless other remedial works were done by the builder prior to the previous owner.
I may ship off to Rick Wood a local garageista, as the Peak District becons, but needs to warm up first,
Also I have a engine temp issue as it ran barely on the bottom mark! I did read a post on air locks ( groan) so will try to examine that too!
Any ideas chaps?:frusty::drum:

limpabit 26th May 2015 13:56

If it's running very cool, check there is a thermostat fitted.

I would for curiosity, set tyres as per bigrich and see what the difference is. What tyres have you got?

5exi beast 26th May 2015 14:05

Current tyres are Yokahamas 195/50/15
And noticed the rad fan runs constantly!

limpabit 26th May 2015 14:12

Got some investigating to do!

Guessing it may have been over heating at some point so hence the rad fan on constantly rather than ECU controlled. Also may have removed the thermostat.

bigrich 26th May 2015 19:16

Hi Martin,

Rad rans running this from cold start or just once warmed up?

Also what does the idle run at when warmed up? Should be around 850rpm......if it is around 1200rpm and constant rad fans then this is usually the ECU seeing a problem from the coolant sensor and switching fans on full time and raised idle to circulate the coolant quicker.

I had similar problems when I reengined - turned out to be an airlock that caused water temp at the ecu sender to go to overheat and cut the fans in.....but because the water wasn't circulating due to the air lock the temp gauge was low. Another pointer towards coolant problem would be if the temp gauge drops / rises when revving the engine.

Check the vent valve on the rad top pipe too....often air accumulates there if stuck in the front part of the system.

I solved by plumbing in extra vent valve on the heater circuit and a vent line back to the header tank.

Limpabit's advice about thermostat is also good - while you're checking it is there put it in a pan and boil it up to test operating temps.

...while I remember - the K series has 2 temp sensors for coolant - both on the same outlet elbow above the gearbox at the back of the head. One is for the gauge only, the other is the signal for the ECU. I can't remember which is which but it's an easy google search!

New temp sender isn't dear and you can change them without draining the coolant down if you are quick!



5exi beast 26th May 2015 20:10

Hi Rich
Thanks for all the advice, I will her check tick over, though didn't seem from memory that high, but I did get out quite quickly! {and kiss the driveway}:flypig:
I will order and fit a new thermostat and both sensors, no point playing at it.
even at 60-70 for 130 miles the needle only moved gradually off its bump stop and up too the bottom of the scale.
Big check day tomorrow, hopefully with more to report!
I keep popping out and lifting her cover, she a purdy one alright!
Anyone know about the Javan R1 on ebay, as it seems to be a clone of the 5exi but 5 times more expensive!!:eek:

bigrich 26th May 2015 22:41

Hi Martin,

If replacing the thermostat try and get one with a 'jiggle pin' (or drill a smallish 2mm hole in the 12 o' clock position in it.....this really helps the air locking problem when refilling.Note - refill really slowly. If you glug in the coolant you'll struggle to get the air out.


All times are GMT +0. The time now is 11:42.

Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2022, vBulletin Solutions, Inc.
Copyright Madabout Kitcars 2022