J-Madd

Octane boost won't raise it that much.

Is he gonna have any big races this year? I love that track.

I ALWAYS gear mine like that(for sand anyway). Peak HP rpm is key. I calculate mine, and they run almost the exact calculated MPH if i know that RPM. You might handle some overev with asphalt and especially with a custom ignition curve. I have a 10 mil Cub with straight cuts and 1 without. The one without is faster (not because of the gears, it's just a better motor).

If you could get ahold of some 44mm Lectrons and set the needles so it idles high and even sounds lean when launching (without the launch limiter) I think that is key. I know You're comfortable with the pwks (and they will work good). I know you talked about possibly using Lectrons before.

Lectrons?

I always heard you could run amsoil 100:1. Klutz supertechniplate FTW. 32:1 on gas. Won't smoke much when warm.

If it really has 60 psi it won't even start. It could be cylinders for a 4 mil crank with a stock stroke crank and have that psi, and run like shit, but still start. A bad worn out motor will still have near 100 psi.

So is it revving, but not accelerating? That would be a clutch issue. If its just falling on its face, something else is wrong. My unported Banshee pulls 15/41 in 6th gear easily; and I have ran 16/41. I had a stator cause that as well, as Jessie pointed out, The more load you put on it, the more the stator issue shows.

The cable probably needs to be replaced.

Sounds like the compression is low, but 145 psi sounds ok (depending on dome size.) When did it start doing this? Is something dragging the motor down (brake sticking, bearing)? You should pull that gear no problem unless you weigh a lot.

What tires?

That can work, but if you go too far it will give it less throw, because the rod will fall off the lobe of the actuator. I have even seen welds applied to the actuator (on a big drag bike) to increase the duration of the lift (like a cam).

How much do you want to spend? It maybe hard to make those cylinders work for a 4 mil. Start with virgin cylinders or go Serval for 4 mil.

X3

Make sure the carbs are sync'd. Shouldn't foul 1 plug that bad and the other look good.

I have a short rod 421 that runs awesome. Did have some cracked skirts though. Not sure the short rod was the issue. I have mixed feelings about the short rod. There can be advantages in how it performs, but maybe longevity issues as mentioned.

Does it have an override? There's more in it than that I think.

It would bring out the worst of both cylinders. There may be a small range of Rpms where they work together.

Any of the site sponsors can get those to you quick. You can always go to bikebandit.com and get them in a couple days as well for a little more $$.

There were only 3 (out of 12 - 16 that were in the class) that even qualifed in the the 3.s. My rider had 0.450 lights all day long and had most of the field covered by at least 2 tenths on the e.t.. That's why I said we could have won (that class) with any pipe. Not close to record breaking passes in that class.

That's taking my post a little out of context!

Flat tops are lighter. I wouldn't think the piston dome profile would matter though, because the actual combustion chamber is gonna be machined according to the piston crown or lack thereof. I could be wrong. I ran flat tops in a motor, then went to new domes and crowned pistons along with a smaller bite and it runs as good or better.

It can take a long time. You can get a break bleeder pump and do it a lot quicker.

I know Shaun with Currie Motorsports out of North Carolina swears by them on his 421 Cub. It has been some 3.6s. Not sure on your port Job though. Shaun's exhaust duration is waaaay up there.