Running 93 did nothing for you at all and actually probably would performed better with 87.VelociRaptor said:I ran 93 when mine was stock(didnt have to but I did) and I run 100ish octane now(3gal. 93/2 gal. 111 in a 5 gal. jug) with my 11:1. I have ran 93 with this setup a couple of times but it gets hotter faster when I did. I wouldnt even consider running anything less that 98-100 with over 11:1
I'm not wanting to start a argument, but I have a few questions, I too... have built motors on more than just single cylinder quad motors. I personally never heard anyone running a 12:1 piston setup in anything that couldn't run fine on 93.Geisick said:You guys are too fast for me. I just updated all the engine kits with new prices and info on them. I was gonna make a post this morning about it.
As far as the octane level to run in you engine it depends on a lot of factors. Just because you can run 12.5:1 pistons with 93 octane in a z400 motor doesn't mean you can in a raptor engine. Bore size, combustion chamber shape, piston dome shape, and a bunch of factors will ultimately determine what octane to run in an engine.
Heck YFZ 450's come with 12:1 compression ratio from the factory and run on pump gas just fine. This doesn't mean a Raptor at 12:1 should also run on pump gas.....
It is true that if you run higher octane than needed you are loosing power. At the same time I would rather error on the high side than run too low of an octane fuel and destroy an expensive engine from detonation.
You can't use a chart, especially that one. There are simply too many factors involved to assume that any one chart can encompass multiple internal combustion engines. Now if someone took the time to create one for the 700R then it may be useful, but one could never realistically account for all the variances that any owner could come accrossed. What we do is listen to those who've run a similar setup and try it out ourselves. If it works then we're set, if it doesn't we have to do a little more experimentation.Chicagoland Atv said:More info on why and really to answer your question > http://www.faqs.org/faqs/autos/gasoline-faq/part3/section-1.html
And as you can see by the chart they list 9:1 compression should be over 93 octane but because of how the motor is setup we can run 87 on a stock engine.