SonOfSand

Can you explain what you mean by "top case filled for better sealing on the base gasket"?

I think HJR is in So Cal, is that close to you?

Well you can probably only port the cases when they are apart, so this will be the perfect time. 2-3 horse for 75 bucks, plus the peace of mind of no regrets.

Is your engine currently a 4 mil? If not, step up to a 4 mil (you will need a reinforced crank anyway) and while the cases are split, have the match porting done. Problem solved!

I will, where do you guys camp, and what color is your rig?

If you spend most of your time at coral pink or sand hollow, keep the red one, however, if you enjoy sand mt more, keep the other.

Andy, do you have any 4 mil stock cylinder dyno runs you could post for comparison?

pancake bearing.

I cant wait for this!

There are some crazy numbers being thrown out. With almost identical mods your friend has, I ran 168 main, NVCQ needle on 4th from top, and a 48 pilot at glamis (sea level) for two seasons and the engine ran perfect. I moved to Rexburg ID (5000 feet), and I was way down on power. You need to be around 160-162, needle on 3rd from top, 42-45 pilot. That's where I ended up and it was better. After I built my 450 into a 480 with webs and 12:5:1, I had it dyno tuned locally, I made the most power and had the flattest curve at 155 main, 5th from top... go figure.

I am jealous, I have had a 10 mil serval on my mind since the announcement. How are you setting it up?

LOL. yes.

Please stay away from Vito's, my friend bought their 421 kit last summer, the nikasil flaked off the cylinder wall on the first ride, he sent the cylinders back to be re-sleeved which he had to pay for, now it wont make any power. He missed the whole dune season. If you do a search you will find similar stories with Vito's. The best bang for the buck is the 4 mil stock cylinder build, Herr Juggs Racing is a site sponsor, and is one of the best at building banshees, do yourself a favor and call him.

The term "4mil" is in reference to how many inches over stock the stroke has been increased. 4 millimeters, 7 millimeters, and so on and so forth.

What about splitting the difference and running Avgas (100LL)? Is there a happy medium of timing an compression that would give enough gains to justify 100LL @ $4.70/gallon? Or has the law of "diminishing returns" set in at 91 octane? Thanks for all your feed back Andy, I think about Servals all day now.

I am with this guy, I have a friend that bought the vitos 421 kit, nikasil came off the cylinder wall on the first ride, so he had them re sleeve, now it wont make any power.

Dual 38 mm carbs is to much for your current setup, and is more suited for drag racing. Like mentioned below, a 4 mil crank and correct porting is the best bang for the buck, and will surely feed your appetite for speed. From there you can move up to a cub quite easily. YOU CAN TAKE YOUR CAPS LOCK OFF NOW! We can hear you.

Just an Idea, don't spend the money on welding your stock crank, eBay for 100 bucks or so and buy a 4 mil crank, send the cylinders out to be ported, reassemble and you will have a totally different machine.

1. Get a cool head before you port, or at least mill the head. 2. The cool head will come with instructions on how to install. 3. Buy the cool head from Kevin so he can get the right domes for your application and elevation. 4. Kevin is the MAN and can help you with all of this. 5. Anymore questions refer to #4.

My friend had his platting come off on the first tank, he sent them back to be re-sleeved and now the thing will bearley climb choke cherry.

Lets see you dune from egin to devil's and back, and make 5 passes up choke on the way... LOL

ForceFed, you have had me hanging on you're every word. I have almost purchased a cub several times but have been reluctant too due to the nature of the power, now I am so glad I did not. The testing you have done on the cat has me very excited, I am only a dune guy, and want more low and mid with out losing any top end. I Love my HJR 4 mil stock cylinder, do you think I could love this even more? regarding Snop, could you expect anything more from a guy who keeps an avatar like that??

In what picture can you see the small exhaust ports? So my OEM cylinders don't have boost ports or triple exhaust? This is why the cubs make so much more power? Thanks for all you're explanations Daj.

Hey guys, looking down the through the intakes on the top picture there are ports in the bottom left, and right hand corner of the intakes. I don't remember seeing these in my OEM cylinders, what are they?

Wouldn't you just buy a cub instead?