Thanks for the resurrection of the thread.
I too have the new VZ-R Ver. II and run it in my MRX4-R. Down here in TX, we run a Spec series for the 1/8th on-road class and the VZ is one of the accepted engines. Our first race was rained out and we are scheduled to run this weekend. Throughout the break in period and some practice time on our track it has been a solid engine. This weekend is going to be the BIG test though. We are hosting a well known annual race , the Gulf Coast/Speedline Grand Prix, and we have 3 qualifiers on FRI, 3 more on SAT, then the mains on SUN. I bought a spare conrod when I got the engine - hope to leave it in the bag. I have been running Rocket Science 30% Nitro content in the VZ. Used the same fuel for break in using a ten tank system. I have found the VZ to be an easy engine to tune. I also run an INS box and I have gotten extended run time. I hope to pit in the six minute plus range.
Let's keep this thread going and help each other with tips on this engine. Looking forward to any one's feedback.
Roger

SORRY - DOUBLE POST DUE TO SLOW SPEED OF FORUM SERVER

I have bought a VZ-R ver.II too. The finish quality is not top notch, but reasonable. I will write some more info when I have find any change to test the engine. What pipe do you use with this engine?

I was curious if the motor in this pic was closer to production, or if its been released in Japan.

The engine in the picture has the same head as mine but the VZ-R Ver. II that I have has a black engine casing. Can't tell much more than that from the picture.
Roger

The pipe that I am running is a 2031 with a medium header.
Roger

Ok - I told you that I would report on the outcome of the VZ-R during this 3 day race. Ran 3 qualifiers on Fri and 3 more on Sat. Mains were run on Sun, March 30, 2008. In the Spec Class, several engines were allowed as long as they were no more than 7 ports and not factory tuned or modified. No problems from this OS VZ-R Ver. II racer. Qualified 3rd and finished 2nd in a 30 min "A" Main. (Mains were scheduled for 45 min but shortened to 30 min due to a rain delay early in the day) First and second ran the VZ-R II's and the next three ran Mega ZX's. At the end of the 30 min main, it came off of the track at 222 F. Not bad. I pulled the plug after burning off the fuel, in order to give it some After Run Oil, and it looked GOOD. Also, I should tell you to run your own fuel tank run time. My pit man and I were really surprised on how much fuel this little engine makes. Your times may differ due to tuning and conditions and I will not let out my run times in the case some of my local friends peek at this thread. You will like what you find and so will your pit man because you will be able to work him less than the other guys' pitman.
Have fun and let us know about your thoughts on this power plant.
Roger

Okey, congratulations on your 2nd place podium finish.

My turn will be 6th of April, I'm gonna try VZ-R ver.II versus novarossi and others

This is brand new engine, and I want to see the difference against other engines.

asw7576,

I will look forward to your report. While I was happy with the VZ-R II, I was running against similar power plants. I do not think that it will produce the top end that you can get from a NR, RB, Max Power. But Good Luck and let us know how it goes.
Roger

Hi there,

I just got back from 1/8 race today, and I got 3rd ( Group B ).

Regarding VZ-R v.II versus anything else like JP, 35Plus21, RB etc.

Acceleration : more less about the same

Top Speed : this is problem. VZ-R is no match to Italian engines at high revs. They were tailing very easy upon straight line, but I defend my racing line the best I can. Sometimes they made it overpassing me ( and crashed upon corner entry ), sometimes they back off ( safe driving ).

ASW7576,

Good job on getting on the podium! Yep, I agree that the acceleration is not far off the pace but I too found that the top end is where it lacks. That is why I race it only in a Spec class and club races. I am looking into an RB C6 or even their new Xenon Alpha for use in bigger races, Master Class. So how were your time intervals between pit stops? Did you find that you could stretch it out longer than your competitors?
Roger

Oh yeah, refueling can be strech to 5 minutes + 2 extra laps. However, I play safe, my refueling is 5 minutes or 5min + 1 lap.

If I want to go to 6 minutes interval yes I can, my engine temp was only 101 Celcius (214 F) during heat. Neverthless I feel reluctant to lean it because some of my friends have broken conrod or glow plug's filament fell into piston cylinder.

If the engine has some good torque, is it not possible to gear it a little higher than usual, to get rid of the lack of speed?

That's actually what was happened in my mrx4-r. My 2nd pinion gear is already 1T bigger than standard car. It's still slower top speed compare to other cars.

I test my engine last weekend. And yes, low end of the engine is very good but it has lack of high end. I test it with a nova 2630 pipe and long manifold. Then due to the weather conditions, I can not find any change to try a short manifold. I install one tooth bigger second gear pinion, but it is still a bit slow on the back strait compared the novas. But it is very reliable and easy tune engine. And considering the price level, I'm happy with it.

Hi Guys, great to see a Thread like this, i personally love my VZ-R, yes i run nova but there is nothing like a good reliable and honest engine like the OS. Just to keep you Guys Posted, i have just recently Bought a OS SPEED VZ-B Crankshaft for the VZ-R, so far from running in the engine it seems ok, This sunday will be my true test where i will be using Tornado Fuel for the first time and the motor is ready for some Throttling, will keep you guys posted.