Topic: 31-33 Avs factory pistons

[Jim Knutson]

Yep, there's some of that good ol rocket "science" ron, being ever so helpful...and such a salesman, don't you thinhk?

[Jeff McKelroy]

Maybe my mis-understanding,  but doesn't target rpm play into the equation?  I understand using the longer rod to slow piston acceleration and increasing dwell time at tdc/bdc. Given intake port velocity as force for cylinder filling, the longer dwell time makes sense.  But, what's ideal for a 7000 rpm engine isn't the same as 5000.  I'm trying to take the fact the stock parts are designed for 36-3700 rpm and optimize for use at 5000.  As Ron stated, maybe I am in over my head, but that's why I'm trying to ask questions in order to better understand.  Yes a different camshaft would be the first place to start, but our rules won't allow it.

The best thing for you to do, then, is build around your limitation. The three C's of any build: Cam, Carb, Compression. All MUST BE complimentary. No sense in having 10:1 compression and a carb built to the max with a 1.3" bore if you can only use a stock camshaft.

I will say one thing, though. Start looking around for different camshafts. The new replacements ones are limited to three designs, but I'm talking about the pains-taking process of going through every engine you can find. All lifts are the same, but the lobe separation is different, and might be an edge you are looking for. You will need a degree wheel for all that, and the block, head and valvetrain setup you plan on using.

Even though you may find a suitable camshaft, REMEMBER you still are limited by a stock camshaft.

Thank's Jeff but I sure that one would have been way over thair head's. So I did'nt even try to explain. Ron.

I'm OK with being the bad guy, I'm used to it!

Folks, Ron is able to provide most easily conceivable combinations using either the stock AVS crank, flathead or ARC crankshafts, stock or forged piston, and with practically any bore. "Mild to Wild" LOL.

However, I have found for myself that I need to spend the money on a combination that I think is right, and then try it. Sometimes paper engines conflict with hard metal, other times things work out better than expected. But in the end it is up to YOU the builder to make the choices. Est solum mathematica!

[chavez]

Well, taking what I have for measurements from the various engine components I have to choose from and punching them into desktop dyno, yup.  The AVS rod and piston combo is the way to go. Nothing new for news here.  Although quite a bit to be gained from changing the timing events of even a stock camshaft.

[BIG AL 202]

JEFF YOU ARE NOT THE BAD GUY!! IF THERE IS A QUESTION ABOUT CAMS, CONTACT THE CAM GRINDER! A GOOD ONE CAN HELP! LET HIM (OR HER) KNOW WHAT YOUR COMBINATION IS AND HE (OR HER) CAN HELP WITH A GRIND THAT WILL WORK FOR YOU.
THERE IS ALOT OF SCIENCE AND MATH BEHIND BUILDING A ENGINE RIGHT, TAKE THE ADVICE OF SOMEONE THAT DOES THIS FOR A LIVING OR THAT HAS EXPERINCE. YOU CAN SPEND ALOT OF MONEY WORKING ON A COMBIATION TRYING TO GET IT RIGHT. DON'T WASTE TIME AND MONEY, ASK SOMEBODY, AND ASK THE CORRECT PERSON!

[Rocket Ron]

Well I guess thats why some people spend all thair time on the comp. Insted of in the engine room or on the Dyno. That question is always ansered at the track and not on the keyboard!!! Ron.

[chavez]

So, rocket Ron, you can take a 31" Briggs, required to run as cast head, stock springs, pushrods and valves, Stock rocker arms, cam, valves, crank, piston, rings, intake, carburetor, ignition system, and say you have a proven combination.  I'm not doubting what you can do without rules, but the class I'm in has plenty of them.  Even if you had a magic bullet for that combination, I'd not expect you to release the cat,   My guess is, you won't waste your time with something you can't sell parts on.  I'm trying to learn, if you've no productive input, you are of no help, therefore useless to what I'm doing.

[Jeff McKelroy]

So, rocket Ron, you can take a 31" Briggs, required to run as cast head, stock springs, pushrods and valves, Stock rocker arms, cam, valves, crank, piston, rings, intake, carburetor, ignition system, and say you have a proven combination.  I'm not doubting what you can do without rules, but the class I'm in has plenty of them.  Even if you had a magic bullet for that combination, I'd not expect you to release the cat,   My guess is, you won't waste your time with something you can't sell parts on.  I'm trying to learn, if you've no productive input, you are of no help, therefore useless to what I'm doing.

Oh come on, be nice. I've appreciated Ron's input over the years, so should you. No need to be sassy.

Well I guess thats why some people spend all thair time on the comp. Insted of in the engine room or on the Dyno. That question is always ansered at the track and not on the keyboard!!! Ron.

True, and as I said, "Sometimes paper engines conflict with hard metal". In the end, what happens on the track says it all. Ron, no doubt you have spent many hours of experimentation both on the dyno and on the track, I have gathered that from talking with you, and I never hang up the phone without having learned something. I meant no offense.

[Eatondirt]

Well I guess thats why some people spend all thair time on the comp. Insted of in the engine room or on the Dyno. That question is always ansered at the track and not on the keyboard!!! Ron.

It takes some one that has broken parts to find out where the failing point is.  A computer program just tells you what is "ideal" not real world.  I also learn something new ever time I talk to Ron .

So, rocket Ron, you can take a 31" Briggs, required to run as cast head, stock springs, pushrods and valves, Stock rocker arms, cam, valves, crank, piston, rings, intake, carburetor, ignition system, and say you have a proven combination.  I'm not doubting what you can do without rules, but the class I'm in has plenty of them.  Even if you had a magic bullet for that combination, I'd not expect you to release the cat,   My guess is, you won't waste your time with something you can't sell parts on.  I'm trying to learn, if you've no productive input, you are of no help, therefore useless to what I'm doing.

On a stock motor the cam is what will always choke it up.  That's why the rules dictate a stock cam.  There are small things that will help but the things they do to a motor with a aftermarket cam won't work with a stock cam, may even hurt performance .