Don Terrill’s Speed-Talk

Something else to consider is the vacuum reading from any pump or evacuation device will be controlled by the size of the clean air source inlet. Most PCV systems use the air cleaner as a filtered clean air source and that air source flow provides a negative pressure/vacuum loss when reading the cra...

For cheaper cast cranks Eagle has a 3.800" stroke for under $400. But the cheapest cast 3.75" stoker crank is Ohio Crankshaft for less than $250. I'm talk'n only 1 piece rear seal cranks here. You mentioned all you need is a crank. I would buy the Ohio Crankshaft piece and use the savings ...

Here's a 3rd Gen camaro using exhaust evacuation and he only gets 2 or 3 inches of vacuum at 4000rpm:
You exhaust system may be different but its fairly easy to measure with a vacuum gauge.

To aid ring seal you want closer to 12" Hg vacuum.

The exhaust operated CCV system will only be effective at near wide open throttle. You can find a video or 2 on U-Tube that show the results on a street motor. At low rpm and high manifold vacuum you need a PCV valve and carburetor or EFI tuned to match it as the exhaust won't pull enough vacuum at ...

The steel ball used for oil passage plug was started with the Gen II blocks I think. I like it. Easy to remove and install. You can free it up with a long rod but you still need to remove the rear main cap to let it fall out.

Like hear opinions on running a PCV valve on street performance V8,s up to say 700 HP, ive always used them rather than a catch can, idea being to vent the crankcase better than catch cans that just vent to atmosphere. Is using both a catch can and a PCV the best solution ? STD tension oil rings, i...

Not lambda, although I do have that option. This is the actual a/f ratio. I started with watching the afr at idle speed in park. Slight tweaks on the mixture screws can get an average of 14.7, but it’s fluctuating between like 14.2 to 15.2, constantly. Adjusting the idle mix screws can easily move ...

Just a WAG but another possible problem could be deep spring pockets allowing oil to puddle up high enough to get sucked into the guide. This was a known problem on some early AFR sbc heads with huge spring pockets for huge double springs.

Any pictures with the valve covers off?

Fluctuation at steady speed? Well if your driving the car it's horribly difficult to keep the load and rpm steady. That's the advantage of an eddy current dyno as it maintains a constant load so very well. Now watching the A/F while in neutral in the driveway is not loading the engine at all but sho...

So lets look at a 350 ci chevy at only 2000 rpm. That's 350 cubic inches of air times 1000 per minute at 0.8 efficiency = 280,000 cubic inches of air per minute and divide by 60 = 4,700 cubic feet per second. Well a 55 gallon drum has only 7.4 cubic feet of air so the engine would empty that 55 gal...

How can you tell if you have enough /or not enough plenum volume. What are the tell tale signs. I was chatting with Another builder and he said when your peak tq stacks up for 3-400 rpm thats a sign. What are your guys idea on that. What im saying is when you have your peak tq numbers hold nearly t...

Piston speed is to high for uetectics with 3.75" stroke. Maybe in a truck keeping rpms below 5000 they would live a long life but I think you are gambling. uetechtics are stronger than cast and plenty of cast pistons in truck motors. But increasing compression and running at higher rpms will te...

Most sbc dampners are neutral balanced with only a few exceptions. So size does not affect balance. The larger the dampner the more effective it is so you want to use the larger dampner though many times this means moving/replacing the timing tab and re-verifying TDC on #1. Now some owners use a sma...

I agree that LT4 cam is not the best choice for a truck used for towing. I use the RamJet 350 cam (#14097395) in my '94 Z28 and it's got plenty of low end torque which burns rubber as much as I care to and more. You could also use the RamJet 350 intake manifold for torque as the RamJet 350 combinati...

More recently I've become more interested in heat transfer and I like this product from Dow Corning (Dow Corning 340): https://www.leadingedgeairfoils.com/silicone-heat-sink-compound-5-oz-tube.html It does dry up so you need to clean the plug and threads in the heads before reapplying if you remove ...