Don Terrill’s Speed-Talk

The first carbs called 950's were simply 750 sized throttle bores with an 850 baseplate. They flowed barely more than what a 750 does. Later, they started using increasingly larger throttle bores, so the actual flow numbers have increased. Some of the larger 4150 throttle bores have very little vent...

Be Careful. There are people out there selling Nitrided Iron Gears, and just calling them "Melonized" gears. To run against am steel roller cam(8620 or 1050 steel), you need a Melonized Steel gear. Make sure it's Melonized STEEL So there is zero need for the bronze gears anymore? True Mel...

It's common for rods to be wider at the parting line than up and down. Some actually use shims between the cap and rod during machining to make it even more egg shaped. This 'extra' was very common when stock rods were pushed to high rpm, as the sides would pinch in under high loads. As for how MUCH...

22R type engine with twin rocker shafts- going back over head stud retorque and want to set up the rockers cold a little closer than they are now (will revisit when hot). Comp calls for 0.010 I/E hot, wondering what you have found gets you pretty close, I'm thinking 0.008 for both? On traditional p...

Subtrack 0.006" for aluminum heads, and call it good. You can re-check the lash hot on a valve or two to make sure that number works with your head. It's better to be too tight than too loose. Try not to overthink it.

Fuel is a blend. It consists of components that vary from very light, easily evaporating fractions... to heavies that don't evaporate quite as easily. When blended to an 'average' they work just fine. All fuels are blends of several components; each present for a specific purpose. "Average&quo...

The problem with avgas is it doesn't want to readily vaporize. That fuel has a high initial distillation to prevent the fuel from evaporating in the fuel system at high altitude, vapor-locking, and stalling the engine mid-air. At ground level, it's junk, but planes don't care much about ground leve...

The best inexpensive 'race gas' is 100LL AvGas. If more octane is needed, mix in some octane booster containing MMT. Makes surprisingly good stuff. A small amount of MMT from the octane booster works in conjunction with the TEL in the AvGas to increase the octane significantly. There have been some ...

Crower has a set of their stud mount 1.75 ratio N head rockers on clearance for $298. For someone looking to put a set of these heads to use, that's a killer deal. https://crower.com/clearance/aluminum-rocker-arms-ford-289-302-351w-351n-1-75-7-16.html https://crower.com/media/catalog/product/cache/3...

Since everything is the same price, I personally wouldn't pass up on the cubic inches. Paul, I agree. The internet has helped a lot of guys out, but it has also perpetuated some really stupid myths. The 393/408C is another one of those perpetuations. I personally see no need for the 393 rotating as...

Something he had a jig for, or custom made? Nate said he had a jig for these... and they weren't cheap, but not insanely expensive. Hopefully, Nate didn't have to pay THAT much. A buddy paid Lemons $2,500 for some 2-1/4" tubes for a 632 in his Chevelle a few years ago... and they fit GOOD. I b...

This place has been around since at least the early 90's... and their website hasn't really changed. lol However, I as well as some of my friends have used their stuff, and have been very happy. A variety of nice Ram-Air boxs/designs, along with various bases and lids available. https://ramairbox.co...

306 stainless of course, roughly $ cost? He charged me $3500 in 2016 which included single tailpipe exhaust and a magnaflow muffler Something he had a jig for, or custom made? Nate said he had a jig for these... and they weren't cheap, but not insanely expensive. Hopefully, Nate didn't have to pay ...

I bought a set of Edelbrock FE heads years ago... and you could see daylight between the valve and multiple seats. ALWAYS check new stuff... no matter where it comes from.

Interesting stuff, never seen a Spintron in action. I can't seem to find any guideplates for 11/32" pushrods. What's the common solution here, just grinding some to fit? I know they're hardened so that would have some level of impact. 11/32" should go right through the plate no problem. T...