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Solid lift flat tappet cams or hydraulic flat tappet.

I got my third X!! Glad I am stimulating the thread.
The only experience that I have with solid cams is from dirt track racing days. We adjusted the valves before every race night.
And there ya go! Adjusting the valves before “EVERY RACE” while a street car… once a year at best once it’s dialed in…. Dang! I check but haven’t bothered in years.

Race car = high maintenance
Street strip = medium maintenance
Stock = low maintenance
Hydraulic cams are what Mother Mopar put in the majority of its vehicles, even muscle cars that meet the OPs criteria.
90% street & 10% strip.
No argument there. A good HFT is all ya need…. Now we need to know his goal. A solid is not a bad choice ether. Generally I would only recommend it for more RPM.
I'm getting older and softer, I guess, & don't see the point of maximum horsepower in these old classic cruisers, they are already bad *** from the factory. He asked for opinions, there is mine, with explanation. No hard feelings on my end.
I wouldn’t have any hard feeling ether. Stock HP factory cars were bad *** but… compared to today, not so much.
 
They aren't comparable to todays factory hot rods, and we shouldn't try to make them to be. It's just not safe. Enjoy them for what they were designed to be. There I go getting soft again, I never used to think about "safe", just fast. Just my opinion.
 
They aren't comparable to todays factory hot rods, and we shouldn't try to make them to be.
Solid cams?

Now that’s a great one liner joke!!!
I’m gonna use that one! That there is some funny *** ****!!!
Excellent sarcasm!
It's just not safe. Enjoy them for what they were designed to be. There I go getting soft again, I never used to think about "safe", just fast. Just my opinion.
Sorry, what’s not safe?
 
One thing to weigh in on the decision..good hydraulic lifters are close to the same price as solid lifters. If your trying save a buck, be careful w Cheap lifters. They can have issues getting through the break in, and if you get through that..don't be surprised if bleed down issues show up, and you get to enjoy valvetrain clatter. Imo 20+ years ago using hydraulic cams is different then today.
For performance and drivability solids just don't give much trouble if you are capable of adjusting valves and can swing adjustable rockers go w a solid cam and don't look back.

Sorry, I must have missed the memo not to run stroker cranks and roller cams on the street. Guess it's to late....oh well.Lol
 
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He said that stock HP classic cars are bad ***, but not compared to today's factory HP cars. I said it's not safe to try to make these old classics compete with the new stuff.
 
He (I) did say that and then again, if one wanted to “Up the Aunti” on everything to (somewhat compete?) Frame and body stiffening components are available.

A Multiple 8 speed transmission, not the stock unit, is available.

Of course, depending on how thick your wallet is may just be the limited on making your old car perform as well or better than todays muscle cars.

Once you get into HellCat territory, you might have to wonder if the effort is worth it or just get a Hellcat.

IT’s a matter of addressing the short comings of the older engines. Todays cars have things we can step up to.
Fuel injection
Computer controls
Super flowing heads as cast
8 speed transmissions
 
He has a solid, it's just too big. So he already has an adjustable valvetrain. I would simply get a smaller solid flat tappet cam (and lifters)
I like the voodoo grinds. Could do a Hughes too.
Cam selection would depend a bit on compression ratio. Too small might bring on detonation if cr is too big.
 
I run a SFT in my roadrunner street car. I check it about once a summer and its usually a wasted effort. Main thing is use decent rockers and pushrods. It’s the Mickey Mouse valve train that makes solids a pain in the ***.
 
Daily driver gets a hft (if it's not hr already). Performance car, some strip use, gets a sft. Race car, bracket or otherwise, even with some street use (wacking the throttle at in-n-outs drive thru, LOL) gets a solid roller.
Obviously, my rules. Everybody has the right to do things THEIR way.
 
My experience with solid flat tappet cams is in my drag cars. With good rocker arms and good adjusting screws they didn't change much if any, 7000+ RPM. I bet a street motor with good valve train would need a valve adjustment about every 12,000 miles or more. Just My Opinion.
 
Anything performance, use the solid lifter cam.
Hydraulic if you don't have an adjustable valve train, or the build is fairly mild, like 230 duration or less @ 0.050"
 
I would go solid. I have a sol roller in my engine, driven once a week, check lash every two years. If you run the engine hard, you will have to check lash more frequently; if you use the random checking method, it is very easy, accurate, no turning the engine over by hand, done in 45 min once the v/covers are off.
Solid lifters can do things that hyd lifters cannot do:
- never pump up
- never bleed down & make noise.
Those are two very "solid" reasons to run solids...pun intended...lol
My 383 with SFT revs flawlessly to 6000, all day, never could with cheap comp hyd
 
I believe your best choice between the two, will be solid flat tappet.
When paired with an EDM lifter, you can get a bit more oil between the lobe and lifter at the base circle of the cam cycle (at lash point when lifter separates from the lobe), providing additional lubrication and a bit of cooling effect.
This wouldn't happen on a hyd flat tappet camshaft / lifter arrangement (lobe constantly contacting lifter)..
With all the troubles in wiping camshafts these days, I'll take any advantage I can get..
Up to this point, I've been using this arrangement without any issue... And no " Constantly adjusting lash" BS!
I am however switching over to a solid roller setup (If I can ever find one)!!
I agree with those who say, a solid flat tappet is probably second best with a solid roller being top choice... Especially with today's oils!!!
 
I currently have hot rods with SFT, hydraulic roller, and solid roller. The lash (preload) on the hydraulic had never been touched in 18 years. The SFT lash doesn't change enough to bother even checking every year. Both are street cars that see occasional track time. The solid roller in the racecar gets checked every 20-25 passes. It's always spot on with maybe 1 or 2 valves being .001" out of spec. So why do we check lash? Performance? Seldom if ever is it off enough to effect performance. I do it to keep an eye on valve train health. If it's loose at a check by more than .002" I'm keeping an eye on it. If it's .005" or more there is a problem, roller tappet wheel loose, rocker shaft bearing loose?. If it's tight, same reasoning. Retainer pulling thru? valve stretching? The lash on the racecar is documented in a notebook. If one valve were to consistantly be out of spec it would show and get attention.
Doug
 
With the solid roller, I would check lash about once a year after it was set where I wanted it. Lash didn't change over 10 years, but if it did it would have let me know something was not right. I should have inspected the valve spring pressures after 10 years, but I didn't and floated a valve breaking it.
With more aggressive cam lobes, high valve lifts, and high spring pressures the more you need to maintain the valve train.
Most off the shelf cams are designed with moderate cam lobes that don't need super high spring pressures to control them, because the cam manufactures expect the owner will not do alot of maintenance on the valve train. That is why one of the first questions is cam application.
 
Back in the day when I ran solid rollers in my bracket car, I checked lash about every 50 runs, seldom any change. For SFT on the street I doubt more than once a year is needed.
 
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