Powerflex Engine mount inserts from Elise

[thetyrant]

Interesting.. I must say the vibration has died down significantly in my setup, but if I could halve that then that'd be grand...
Did you just use a stanley knife?

I was hoping to be able to cut them with a sharp blade but PU material that mounts are made of is pretty tough so that didnt work out!, to remove the excess flap around edge i just used belt sander/linisher and then for reducing overall thickness i ended up using a sharp wood blade in my chopsaw!, bit dicey as you have to hold the insert upto a stop then slowly shave off a blades thickness from it, all without cutting my finger off!...then just dressed it level and tidied it up on the belt sander again.

If yours are not the exact same insert it maybe different to these yellow powerflex ones.

[Petrus]

Appearently they come in two versions.
The yellow, ´soft´ 70/80SHA for street use and
the black hard 95SHA for race use.
Price the same.

[thetyrant]

That is correct, i would not use the harder ones in a road car unless you dont mind feeling every pulse from the engine!

[jvanzyl]

Appearently they come in two versions.
The yellow, ´soft´ 70/80SHA for street use and
the black hard 95SHA for race use.
Price the same.

huh... that might explain the vibration!!!

[thetyrant]

huh... that might explain the vibration!!!

You will always get some extra vibration with uprated mounts/inserts, it just depends if you can live with it.

Are they Powerflex black ones you have or another brand ?   there are quite a few other brands of black colour ones from usa and not sure on hardness but most manufacturers do publish that, colour doesn't always dictate hardness rating and above info of yellow/black is from powerflex site for there bushes only

[Carolyn]

Appearently they come in two versions.
The yellow, ´soft´ 70/80SHA for street use and
the black hard 95SHA for race use.
Price the same.

huh... that might explain the vibration!!!

As i recall, John, don't you have brand new front and rear factory mounts?  I would have thought, with a head steady as well, that set up is already stiff enough for road use?  I'd be tempted to take the inserts out and keep them to one side for track-day use.  It's not a massive job to swap them in or out, is it?

[thetyrant]

Yes with new mounts and for a road car i wouldn't think inserts are needed for most especially on stock motor, unless you like the extra vibes!, especially if a head steady is fitted ? this was another thing i was pondering but inserts are so cheap and my mount was looking a bit tired so went this way instead.

[jvanzyl]

Yup new front and rear mounts, haven't gotten round to fitting the head steady yet. I suppose I could take them out... just haven't gotten round to it yet!

[thetyrant]

Ok trackday yesterday at Oulton park so put these inserts under some stress, i was going to fit them in front mounting as well but never got time so still just the rear ones fitted, car was epic all day with around 95 track miles covered before drizzle stopped play and i headed home (was too tired to cope with damp track after 5am start!), no issues with the engine mounts and car felt nice and responsive and no problems with shifting so all good, whiteline ARB i also recently fitted helped keep the car balanced in the corners and looking forward to the photos so we can see how much roll it still had, felt better than previous though but better seat is next mod i think to hold me in place!.

Downsides...so even  with just the rear insert fitted (trimmed down version i have to help reduce NVH further) motorway cruising was noisy if pressing on, ive always been impressed with how quiet the car is at motorway speeds and on occasion speed has got a bit higher than i/feds would like because of this, now with the inserts in anything above 80mph (private road of course) gives quite a lot more noise in the cabin!, 80 seems to be the sweet spot for keeping things quiet which is good i guess as lets you know if speed creeps up, above that it is quite loud and weirdly sounds just like a freeflow sports exhaust with kind of a droning noise, but im still on stock silencer which is quiet as a mouse!....noise tester at Oulton asked if it was running when i went over for testing!...it did test@ 90db which i think is because of engine at the back as well as exhaust is not noisy at all.

Vibration sat idling in traffic is a quite a bit also, leads to gentle blip from time to time to help reduce that, if idle was 900 or so not 800 it wouldnt be half as bad.

All in all though nothing too bad and perfectly liveable for me, if it keeps engine better supported im happy to leave them in, im hoping to get down to next sprint at 3sisters circuit in july where i had the shifting issues last time and if they sort that i will be happy