less than 200rpm rough running

[sideways500]

Hi everyone. I've read some interesting threads but this is my first question.

After looking at various Griffith, Chimaera and Cerbera models we finally bought a '94 Griff 500, T5 equipped. Running around town it is necessary to keep the revs above 2000rpm to prevent nasty snatching and transmission backlash. This is in contrast to a '98 model I drove previously (too expensive). Is this a function of engine age and something to be driven around? If not, does anyone have any ideas where to start looking?

[shpub]

Post 97 models were "detuned" to reduce/cure lumpy running t low revs so you could be suffering from that. with the 94. Could be made worse by diff bushes/mounts loose and a knackered rear transmission. Worth chceking PDQ just in case there is something wrong. May only require some TLC.

steve
www.tvrbooks.co.uk

[zippy500]

Hello Sideways, mine is a 95 and dosent do any of what you described, well not as bad as it sounds on yours anyway, as Steve said, get it looked at, sounds a bit weird to me.

[sideways500]

Thanks for the quick response. A trip to TMS I think, unless anybody has other suggestions?

[Toffer]

The 500 does suffer with transmission shunt and earlier ones are worse than newer ones.

My Griff is a January 1998 and runs smoothest on Shell OPTIMAX...try it! I was sceptical until I used it, now I avoid any other fuel...honestly!

The other thing that I find slightly surprising but IMO does help, is float charging the battery. I keep mine on all the time the car is not being used. I reckon having the battery in peak condition makes for smoother running especially from cold...again try it before you deride it!

Good Luck!

Toffer

[sideways500]

Thanks for the help. TMS found a couple of electrical faults but couldn't fully cure the problems. A trip to Mech Repairs rolling road, with Mark Adams at the helm, was required. This seems to have done the trick. They spent the best part of a day investigating and tweaking. This resulted in smoother running across the rev range. The low speed running is still lumpier than others, but Mark believed that this is a consequence of the engine being more revvy than others he has tested. As such this is one of the stronger motors they have seen.

So a worthwhile trip, both for the improvements made and peace of mind gained from expert opinion concerning engine health.

[xain]

There could be something in the battery thing (though my first thought was "yeah, right!") When the fans cut in if I'm edging forwards my Chim really shunts, and feels like it nearly stalled (never has though)

The extra load from the alternator could have some bearing, but I'd have thought it would be smoother if the battery was drawing constantly.