Don Terrill’s Speed-Talk

Thanks for your input. After a very long time I finally cut and lapped the seats with the valves. It definitely helps to do the 70* throat then the 30* top cut first until they meet. Then the 45* seat cuts easier and with less pressure. It wasn't concentric first go, but playing with the pilot etc ...

Here's an example of what I mean. Seat cut with neways. Nice and shiny all round. I mark the seat with black ink and lap the valve to check seating. Result is in the picture. If I continue cutting it does the same thing. Cutter is 45* as is valve in this instance. I'd like to hear people's thoughts...

It's like any tool on the planet, it's all in the hands of the user. Yes, you can cut concentric seats with Neway cutters. Yes it's time consuming. Yes, expandable pilots are about useless. A power head is far better than a T handle but you can get by. The one thing you never want to do is cut over ...

What variables go into calculating port energy? Velocity I assume ... but is it average port Velocity or at MCSA?? Flowbench velocity or running velocity? and area is probably included ... but again the question of which area ... avg or min? What about engine or cylinder cid or port length? What al...

Seeking feedback on a company named Carburetor USA please. Someone I know sent them a carburetor months ago and now they don't answer calls or respond to emails. I tried calling them but get voice mail.

Is this an oil, or a $6000/set valve spring thread? :-k Looks to me like the oil is bait to build up the thread views.....not exactly a new tactic for the thread starter. So someone asked the OP about the oil and now thats the OP's fault? Luckily for DV and others the resident trolls do a better jo...

Warp Speed wrote:Is this an oil, or a $6000/set valve spring thread?

Looks to me like the oil is bait to build up the thread views.....not exactly a new tactic for the thread starter.

Great thread! Lots of input an not a single insult

For all 2 cycle power tools the best oil IMO is Optimal. 100:1 mix ratio is recommended. I've used it for many years in chain saws, weed eaters, etc. In the spring I fill a 5 gallon can with 81 octane gas, add the optimal and run it in all the 2 stroke motors plus my 4 stroke push mower. The mower g...

I'm not going to drop the name. The post is here if you look for it as well as other forums. The individual dynos a lot of engines and has reported that increases in low lift flow have show similar results of adding cam duration. I believe this is yet another one of those internal combustion engine ...

Did you miss the question I asked on bore size Rick? I have a few actually. If you could be so kind as to help me understand the flow around test results I'd really appreciate it. I asked because the flow around test results had all sorts of bore adapter variances. Also I only see a couple of refer...

Did you miss the question I asked on bore size Rick? I have a few actually. If you could be so kind as to help me understand the flow around test results I'd really appreciate it. I asked because the flow around test results had all sorts of bore adapter variances. Also I only see a couple of refere...

If My superflow was calibrated to read what the plates should flow that head would flow 343cfm. I instantly become the Internet hero but the numbers are wrong. The orfice plate test would have worked better if you flowed an orfice then the same head on the benches, like the flow around test. The de...

Here are the results from that Flow Around project.

With new flow benches not having analog gauges the water gets muddier rather than clearer. At least with the old benches you can cross connect the two and verify the digital against the analog to verify the Delta P accuracy / consistency of the digital unit. With 2 different versions of electronics,...