If you were re-building an engine (e.g. 340) for an A-Body that would see 99% street driving to attend cruises/Mopar events, what type of cam shaft would you install? At this time, I'm considering a Comp Cam Flat Tappet (20-228-4) or Roller Cam (20-813-9)? The engine will have a set of stock cast heads that had port work done, but will a freshening (new valves, seats, springs, etc...). The plan would be to runner headers, TBD on intake a carb. No power steering, power brakes or A/C.

For those that purchased a roller cam for their engine, would you go back to a flat tappet? Any current issues with the roller?

Thank you in advance for your feedback!

I was about to rebuild my LA and was going to go with a roller cam. As luck would have it, a Magnum fell into my lap so that is how I went with a roller cam. With all the horror stories on wiped lobes on flat tappet cams, I do not think I will go back.
The modern Mopar engines seem to have pretty long lives with rollers. I cannot speak to performance sacrifices or gains, since I totally changed engines and have no benchmark to compare it to. From what I have read, rollers can have much faster rises so the valves open more aggressively. That IMHO is a plus.
Craig

You are factoring in the cost for adjustable rockers also?

If the budget allows for a roller go that route. I have not looked into the cost to convert for a SB but on my BB it was around $1300 difference between a flat tappet and roller. No real downsides to a roller other than cost and there is no cam break in or fear of wiping a lobe with a roller.

One downside of the roller is the oil pump drive gear which needs to be bronze to run against the steel cam core. Life of the bronze gear will be less... anywhere between a few thousand miles and maybe 10-15k. Heavy oil and high volume pumps can wear them out pretty fast.

Also the roller lifters. Stock magnum lifters do great with stock or a moderate performance cam. Some of the aftermarket lifters not always.

If you do go flat tappet, nitriding the cam and EDM lifters can provide insurance for 200 or 300 extra dollars... probably what I will do on the next engine even though my current FT is doing fine.

I went with a solid flat tappet in my 493 that has been in my 63 since June 2011 when I first fired it up. I have had no problems at all with it and the cam was nitrided and I use the EDM lifters. I went with the flat tappet because I did not want to pull my roller lifters and check them every few years as I would have used a roller that needs alot of spring pressure and I also did not want to use a bronze dist gear but I know they have other gears today you can use on rollers that are not bronze. Many do used rollers and have good luck with them on the street. But I knew I wanted more of a race cam that would have run a good bit of spring pressure so I opted for the flat tappet which Dwayne Porter recomended I use because of the milage I put on my car. I use Valvoline VR1 racing oil that has alot of zinc and add a bottle of the zinc additive at each oil change and I have not had any problems with lobes wearing to much. They both (roller and flat tappet) have their good and bad points but since my 63 is 99% street car I went with the nitrided flat tappet with EDM lifters and I am very happy with it. Ron

I built an LA stroker a few years ago. I went with straight flat tappet. Actually solid lifters. No EDM, no Nitrating. I don't have an aggressive cam profile (comp XE274-S) or real stiff valve springs (std springs w/E-brock heads).

Jus

I've got about 8,000 miles on it. I cruise down the highway at 3400 rpm at ~70 mph. And lots of highway blast up to 5,000 rpm. At least once a year I go out to a track day and wind it out to around 6,000 rpm at the end of two straights every lap.

Destroyed the ceramic coating on 2 inch TTI headers after 512 build using a flat tappet cam during required startup breakin. Got too hot.

Later when replacing iron heads with aluminum heads(to deal with an oil fouling of plugs issue), replaced cam with a roller and at tear down had headers again ceramic coated at a cost of some 350 bucks by the firm out of Fresno.

Because roller did not require startup breakin, recoated headers were not harmed and are doing well And I love the way the car sounds and runs. Wouldn't be surprised if picked up over 100 hp,,,cam and heads together.

For your build I'd go with a hydraulic roller.

I bought a set of TTI smallblock headers back in 2011 because I had two other sets and liked them alot. This is the first set I had ceramic coated (black). Did the break in and tune w/o headers, and coating still went to sh#t within a year. I called and they admitted they had been outsourcing the coating and had an issue with this. Told me to send them back for re-coating. Ya, right. PITA to remove, box and ship, and then all the downtime waiting with the car sitting. Told them I wanted refund for coating but nope.

As far as roller setup; I'm in agreement with those who say if budget allows, deff go roller setup. But if not, then use Valvoline Racing oil with it's high zinc and you'll be fine.

Is it disadvantage to go with roller rockers and a flat tappet cam? I've heard some people say they have a flat tappet cam, but roller rockers. Not sure if that situation would be just wasted money when you are not using a roller cam with the roller rockers.

Thank you for all the feedback thus far!

Why would starting up a new motor with a roller cam run any cooler than one with a flat tappet starting up new?

Pretty sure they tell you not to do that just for that reason.

Well known that flat tappet cams require some 20 plus minutes of moderately high rpm of engine running to break in lifters to cam. Not to mention often reduced valve spring pressures,,,many folks change springs to excessively light ones for break in and then replace with their normal springs after this break in period. Sounds like a lot of work to me.

This running at basically a high speed idle while sitting on an engine stand or dyno in a stationary environment with little air flow cooling can overheat headers thereby destroying ceramic coatings. That's the theory anyhow and in my case did wipe out the coating on the headers.

Roller cams do not normally require this breakin period thereby avoiding all of this.

You asked me the time, I told you how to build a watch.

When does the ground war begin?

Naw!

Roller cam. I don't think you need one all that big to make enough power. My 340 has a 227/231 dur @.050, .530 lift hydraulic roller on a 110 and it made 470hp with 9.7:1 compression on 93 with only valve jobbed edebrocks, 750 double pumper and a box stock air gap. It was spec'd by Mike at MRL Performance (he is semi local to us). Nailed it. The thing makes power everywhere at 2000 rpm and above.

My car has a 4-speed, 3.23's and 25.6" tall tires and it's something you could live with basically every day. Reasonable idle at 900 rpm.

I just looked at the Crane Cams page for LS motors, how about 0.585 lift on a 216 duration at 50 lobe? All right, some of that is ratio. My point is the hydraulic rollers for street use, last for long times with some pretty aggressive street grinds. There seems to be no reason not to go roller except for cost.

So, if you can afford it I say go straight to hydraulic rollers and don't look back. It's kind of like wooden boats and fiberglass boats. The wooden boat is more nostalgic and will do everything all right, it's just that the fiberglass boat can do it better with less work, but with fewer nostalgic feelings about the old days. Shoot, if you really want nostalgia, build a flathead.

It was really nice to build my HR 318 and stick a different cam in it with absolutely no worries about breakin.

Talk to Bullet, they have many hydraulic roller grinds.

R.

If the timing was set correctly...it should not burn up the headers...have done several new tti on new engines (flat tappet)...retarded or not enough advance will make the headers glow...

Agreed, same for a myriad of other conditions,,,misfiring cylinder, lean fuel/air ratio, insufficient coolant etc.

Roller tip rockers can help reduce the impact of scrub over the valve when pushing lift. Also most adjustable rockers are roller tip... which a mechanical cam needs. Adjustable is also recommended with hydraulic when you want to dial in pre-load exactly for best stability at RPM.

Bottom line, no harm in roller tip rockers with a FT cam and actually an improvement as long as the rockers are good quality. Run far and fast from the cheap rollers though.