At 12$ a bottle for the RP im scared of what Amsoil would cost since there is none that I know of that is sold anywhere...



Any particular brands of gear oil? My buddy replaced his tranny oil in his RX8 with RP and noticed a huge difference in shifts, they are smoothe as glass but is that the general "rule of thumb" that comes with changing to a dedicated gear oil over the stock stuff? It seems from the FAQ people (on multiple sites) recommend REDLINE gear oil for their drivelines over the other stuff.

I used Redline MT-90 for my transmission. It is a gear oil specifically manufactured for manual gearboxes. Good stuff if I remember correctly you can get it for around 8 bux/qt. from summitracing.

Ahh yes the internet! That would prolly be uber cheaper than anywhere around here, thanks!

what kind of percentage gain is that? whats the error factor on the dyno? most are +/- 2-5hp

i dunno...it was a show on speed. they used the dyno that was underground. probley a really good one, if they are using it for product testing and TV.

Humm.... Racingbeat has been building and winning races with rotarys for over 35 years... back in the 80's they used amsoil and had some good results with it.. Now days they are using royal purple.. they have dyno results from there in house dyno and it does have about a 2% increase in HP..(on a rotary)



They have been doing tests running the RX8 with RP 2 stroke mix insted of the OMP and they have seen a 1% hp increase..



If racingbeat uses Royal purple I will use it also!

I can get amsoil for around 9 dollars a guart for the oil... and I think the gear lubes were 15 dollars up.



I only run amsoil in my KLZE mx3, it is well worth the money, with just Mobil one in there it felt kinda sluggish... switched to Amsoil the car revs faster and seems to have a little better throttle response... besides if my dealer puts it in his 700 hp Porsche 911, I think I will trust it.

My car runs like a ******* CHAMP right now its not even funny with the actuators actually working, timing done and VDI making a sweet winding noise to redline and on top of this running the RP and a K+N oil filter! I was able to pick up the filter for 10$ CAD since NAPA is having a 25% off sale this weekend! All thats next is to deal with my stupid catalytic converter...



BTW Royal Purple is actually PURPLE...I was expecting the usual bronzy looking ****, but nope...dark purple.

I think we can honestly say that RP and Amsoil are reputible oils to use from a performance and longevity aspect!

Generally speaking if you have a decent brand name oil in your car and change it regularly it isn't going to make much difference. 8HP gain isn't much if you're spending a lot more for the oil. Sure there are ones which work better and are recommended for rotaries but as long as you choose one of them and change is often I don't think it matters much.

Just my $0.02



I'm using MOTUL Turbolight 4100 since that's what my engine builder recommended and he's regarded as the best rotary builder in town where I live. Nearly all high performance rebuilt motors come from his workshop. Plus they (the workshop) actually race and drift the motors that he builds.