Originally Posted by dmb454ss
if you look on page 8 of this thread i asked the question if i'm running 30% should I run the extra shim & no one answered me...
Nine posts before yours asking:
Originally Posted by Corse-R
Strange... past experiences at nats and of 6 different drivers told that adding shims up to 0.60mm worth of shims helped to gain performance.
Probably ambient temps, rel humidity and barometric pressure were way too different, and of course the fuel used (we need to use 25% max nitro).
Could you please put more data regarding this? Which fuel, which plug and other info of interest.
Ten posts before yours:
Originally Posted by michael 1
we ran 3 of them at the rams club here in nor/cal we ran them with all
the headshims .050 total and minus 1 at .040 i belive it ran beter
minus 1 , we did get some hi temps but as art said we our taking the
temp much closer , we got up to 360 , after the race we took them
apart no damage, good pinch, and not 1 plug blown or distorted
they are not jps , but they do have performance and at 1/2 the price
its a good deal .
On the same page you asked it, had two messages of people telling they needed to raise the chamber much than was able to do with the additional shim that came on the box. In doubt, maybe you needed to ask to the place you bought the engine. Specially when you broke the first and go for a second engine.
If the LHS gave you a bad advice or at least suspect of something went wront, probably you could do a quick call to the importer (Mugen Racing and ask about them, for sure they will told you to raise the combustion chamber up to a safe level).
Don't know why, but, everyone who used this engine needed to raise the combustion chamber, maybe on the future, the engines should come correctly shimmed from factory.