The Engine Tuning Issue You Didn't Know You Had

As my old farmer neighbor used to say, "Pay attention, I'm gonna learn ya something!" Thanks for the education UT.

I'm an old timer, was 13 in 1960 and was privileged to live through that golden age of American automobile history. I've been amazed at the 'unspoken' questions I've had, that several of your videos have clearly answered. You rightly deserve the title of 'professor', much more than so many who hang that on their names...but 'Uncle' Tony is much more fitting, as you speak to us in your videos as a wise uncle would explain things to a favorite nephew. I love your 'lectures', keep up the good work.

old motorcycles are my bag, 'but motors is motors'. i like this guy and what he passes on.

One of the things I was most impressed with on the job the machine shop did for me >25 years ago when I modified a couple sets of 360 heads to 2.02 intake valves was that the valve stems were spot on, not even 0.001" difference installed height. Yes, they were brand new Manley Stainless Steel valves so would have all been the same length to start with so they didn't have to grind any stems or anything, but they bothered to actually grind the seats precisely to depth so each installed spring height, every top of valve stem was bang on Impressive! I loved that machine shop. Did three engines at once that time, two 360s and a 351W. They assumed I was a race team or something, kept going above and beyond for me at virtually no extra charge. Shot-peening and stress relieving rods, equalizing weights to fractions of a gram... Geez, they only charged me $200 a pop to do full spin balancing on the whole rotating assembly including dampers and flywheels. Ah, those were the days!

This episode by Uncle Tony is equal to the best one he's ever done as far as helping out average backyard mechanics and engine builders. He explained things in a simple fashion that anybody could follow.

You have taught me so much Uncle Tony. Your FACTUAL KNOWLEDGE and willingness to teach people is greatly appreciated and underprized.

Back in the 1989’s I helped my dad rebuild the 318 we put in my pickup truck. He said the exact same thing. He also matched the shortest pushrod to the tallest valve stem. He would also use an old lifter and dope the cup with lapping compound and use it to slightly shorten the push rods as needed to get as close to zero lash as he could get. After resurfacing the heads and decking the block he had a local cam shop regrind a stock cam for a low/mid rpm torque motor. A set of headers and a edelbrock torquer intake matched with a 600 cfm Holley carb made that 318 sing. It was a 68 model so it had the high compression heads and a steel crank. My short bed dodge truck with a 4 speed was pretty darned quick and that motor was stout. We didn’t have access to a dyno but from the weight of the truck and the times I turned in the quarter I would guess it hovered around 35-370 horsepower. It was a good street truck and it took down some of the highly touted cars being produced at the time. It was fun!

So what you’re saying is that any performance gains go away if you can’t close the valves, and that just makes total sense to me 👍🏻👍🏻👍🏻

I love how you differentiate between "stated reason" and "actual reason" for pre-load.

It is absolutely nuts how much information you are able to walk through and lay out for adverage Joe to understand.

It's a pleasure to hear how much you can improve just by measuring everything, it's probably what's called BLUEPRINTING

Every family needs an "Uncle Tony."

I got a bunch out of that, I already know how to do all this but I never miss the opportunity to just listen to a pro go over things again, it keeps the knowledge fresh. And Tony's teaching is solid!

Ok, you can jump deep into the rabbit hole very quickly. That make more sense then all the explanations I had heard in my life time. Thanks for sharing.

Here in CALIFORNIA Not many people are getting over 5,000 rpm. Between the cops, traffic, and bad drivers, your lucky if you get to your destination alive. Great video and info.

Such a good, IMPORTANT video! I've had machinists tell me that the importance of having the valve stems perfectly straight was a wives tale. "Without adjustable valve trains," I said, "you've been working on chevy's, and don't know how to set this up correctly do you?" Needless to say, I know why he kept pushing me so hard to buy a Harland Sharp roller rocker set, and why he already had my factory rocker arms/shafts bolted down! Won't be using him again for sure. Keep up the great work Uncle Tony

On my old 340 I took the rockers out of a pre '68 273 as they had solid cams and stumbled across some 6pack push rods (273 push rods are too long). BUT...that was back in the late '70s.

I'm a beginner, messed around with two-stroke engines alot when I was younger.. but I'm now really interested in engines.. I'm busy fixing up just a normal car nothing special like you are doing but I wanna thank you for being a great tutor! I'm learning really fast! You explain it just the right way, keep it up, Thanks!!👍👍👍

Excellent tutorial, Tony. I had always wondered about the differences in preload, lash, and why valves would float in certain scenarios. I was raised on inline Chevys, the early ones had adjustable rockers, but the newer ones had, sometimes quite a bit of built-in preload. I had a good mechanic friend (long gone) who did things similar to how you do. I questioned him once on a procedure he was doing, he told me that I was filling up diapers when he was first doing mechanic work. I never questioned him again! Watch, listen, and learn!

Hi Tony! Wish you had premised this by clarifying that the stock Mopar valve train is far more rigid, removing the larger rocker studs, stud girdles and other bandaids that non- Mopar engines use to control deviation/deflection in the valve train. The best ALWAYS go to SHAFT mounted adjustable rockers REGARDLESS if the motor is Chevy or any other. I have built many GM and Chrysler, love both, but as Guru David Vizard said, in the past, Chrysler was at the top of the heap for rod ratio's, deep skirted blocks, rigid valve trains, etc., Which GM adopted much later. that said, I built and still have a sbc 406 In a 1976 Monte Carlo daily driver at 460 HP (shaft mounted adjustable rockers NOT CHEAP) and a solid roller 440 bored and stroked to 512ci in a 1972 New Yorker with 720hp at 6820 rpm daily driver. Both have been reliable but for periodic valve lash adjustments. I am constantly impressed with all the great content you generate for the new generation on how cool IS the old school!