Does this prove David Vizard's 128 lsa formula ?
i can't believe i wasted 8min reading this...
Now you have at least twice that.
and so do I
I will say though.... i saw a documentary where one of the top DV proponents spent over a year building a $15k+ stroker ford with a dv cam.. and in the end it got smoked by a nearly stock 318 built by a caveman that uses cinderblocks to deck a block...... soo.... you may be right.. (it will never not be funny)
o o o o. Find and post that.
I think it pays to be sceptical.
Someone asked for a DV story. I loved his early books, used his muffler testing and guidlines, and looked forward to his somewhat occassional posts on ST. Now I've posted this before so this the short version. I followed the recommendations in his books to improve my carb like the Carb Shop did for him. Carb Shop had closed so sent it to Quick Fuel (when they were just transitioning from modifying into making carbs). $400 and many months later I began my journey. It cost me a lot more money and time to understand better why things worked and didn't work. Without Shrinker, Tuner and Gregory and lot of time and data collection (and dyno pulls) that carb would be a door stop.
Does anyone ever regret a tigher LSA? Well I did. Went 108 instead of 110 and didn't do what I needed it to do. Again a learning and was able to crutch it with the v-max lifters but they have their drawbacks too - especially for what I wanted.
There is a lot of science involved with engine design. That's for sure. 99% of us just use what the engineers designed. They must have had a reason for what they did and why. It could be for power or economics and ease of manufacture. It comes back to How much power do I need and can afford. The engine brain surgeons can always squeeze a few more ponies out of an engine but at what cost? If you have the know how, a machine shop, and want to experiment go for it.The rest of us will just try our best to bolt a combination of parts together that we can afford and that works. Sometimes that's the smartest thing for us to do.
Well said Mike.
There was a post asking about starting points. Another early lesson for me was to know something about the intake flow and lift. While there are reasons to exceed the lift where there is max flow, that's not what I want to do (again) on an engine for my purposes. So that, and the rules of what I compete in (or think I'll be competing in) are starting points for me. Another critical starting point for me is the actual compression. We have some room here, but without actually measuring the volume its a WAG. I will never do that again!
I like the idea of reviewing the closest options for the effect dynamic compression. And one of those has to be a baseline. A real baseline that you personally are familiar with. Not a problem for the people posting in this thread but a big one for first builds.
I also like the idea of looking at the cylinder capture and will prefer a cam that works with the rod ratio of the engine.
So there's my 2 cents on that subject from someone who uses the dragstrip mostly as a means not an end, and in no way is an engine builder. Just a guy that doesn't want to get burned again.
