Tyre Pressures On Exmo

[Guest Mike G]

Identifying correct tyre pressures is probably an old onion, but I have never been able to come up with a satisfactory answer.

 

My Exmo is currently on Michelins 185x13 on standard Ford alloys. If I pump up the tyres in excess of 20 psi, then the ride is rock and handling on tight bumpy bends sometimes a bit hairy. After some experimenting I am currently running around 16 psi front & back, which seems to be about right in terms of ride & handling. I never use the car on motorways or tracks, so for county-style roads I am fairly happy with this arrangement.

 

Anyone got some positive ideas?

Regards

Mike G

[Big Jim]

RHSC recommend 17psi for the earlier cars such as the Exmo, I have a mark 3, and found that the tyres 'rolled' too much on exuberant cornering. so I upped the pressure slightly a bit at atime until I found what i believed to be the best for me, that was 21 psi.

[Guest Bazwaz]

I'm using Yokohama tyres on my Exmo inflated to 18 psi for normal running increasing to 20 psi if i'm going any distance on the motorway.

 

Barry.

[Guest Greg]

185x14 on my exmo fronts 18 rears 20

ride is rock hard whatever pressure I put in 'em. Have you got the ARB on it or tie bars, it can make a significant difference to the handling.

[Guest Tim Norman]

A harsh ride is more likely to be a supension issue rather than tyres. I run at 23 alround and even harder on the track, but the I also have suspension that is quite soft at the front with an anti roll bar a little more suited to the Hood. It is from a Reliant Robin! The ride is incredibly pliant and on the track is informative and predictable.

Sort your springs out. I suspect they are too hard.

[Guest rizla]

i have to agree with tim on this one it is more like a suspention prob than tyres i ru mine at 24 more when on track

[Guest Bazwaz]

I should of added that my Exmo has tie bars, they make a tremendous improvement.

Barry

[Guest rizla]

i too have tie bars on my s7

[Guest Tim Norman]

Bob has tie bars and an anti roll bar. All cars should have one. But make sure it is suited to the car.

 

Bobsmate

[Guest chris]

Bob has tie bars and an anti roll bar.

I dont understand.Surely an anti roll bar acts also as a tie bar?(or is that what you meant?)

Is the Reliant Robin anti roll bar a straight swop for the original ,or are mods required.I have had a set of tie bars for some time now but have not fitted them

because I am loath to go drilling holes in the monocoque,also it seems that where I need to bolt them is exactly in line with the structure that the engine mounts bolt to,so cannot see how to reinforce the mounting points inside.

regards chris

[Guest Tim Norman]

Chris

The front end of Bob is much modified. The tie bars are adjustable and are higher at the front than at their mounting at the rear. This aids weight transfer under braking. They are also adjustable. The anti rollbar is mounted across the top of the ngine bay and is connected to the top arms of the front wishbones via some drop links from a Rover 820. If you want more info I'll sort some photo's out for you. So they are two completely separate items. On the Sierra based cars they are the anti roll bar acts as the tie bar as well. As it was designed for a big heavy saloon it is too stiff for the RH which is why people change them for independant tie bars. The mistake they make is not replacing the anti roll bar element with someting more suited to the weight of the Hood.

 

Give me a ring if you need more than pictures.

 

Cheers

[Guest irishbob]

hi I have run my car at 19 psi front and back for the last seven years and the Michelin tyres seen to want to last forever. however I very rarely go faster than 60mph as you will see from the report of NW trip to Exeter IRISHBOB

[Guest Mike G]

Thanks Guys for your response to my puzzle. Your ideas are spot-on. I had already swapped over my old Sierra roll-bar for a set of Dave Andrews tie-bars. They stopped the creaking and rattling of the old set-up and made an improvement to the ride, but not as much as I had hoped for.

 

I suspect a change of springs will be the next job. I think my Exmo has the original factory jobs. Any ideas of what I should go for, and the best supplier. The budget is getting a bit tight at present, so go easy on the outlay!

 

Regards

Mike G

[Big Jim]

If the springs are 'standard' lengths & overall diametre, most of the suppliers will let you swop them if you find the ones that you've bought from them aren't just right. Demon Tweeks did when I changed mine. Unfortunately I can't help you with which poundage to go for, with yours being the Exmo. Matt may know, as he used to have one.

[Guest Greg]

I went through this with my exmo............

 

I tried to set the steering rack and bottom arms parallel to reduce bump steer. This proved problematic. The end of the mounting arms for the suspension stopped it going low enough to do this. I reduced the length of the arms and put in a brace and strengthening piece. Then I reduced the spring length because the adjustment on the struts would not let it go low enough...still not enough clearance. Spaced the wheels out by 25mm then I got the necessary room. I messed about with varying spring rates with a small amount of sucess. Too much work to justify the result really. I ended up cutting the front end off and replacing it with a frame and double wish bones. A much better solution I think, but it's major surgery.

 

Greg