Hyd roller vs flat tappet Pontiac

[G-Body_Vet]

My initial Poncho 455 build included plans for a flat tappet Crower cam. Being that I'm going to take longer than anticipated to finish the build I'm thinking about going hydraulic roller instead. Yes, there's quite a price difference. I'm thinking the cost of good oil (like Brad Penn with the proper ZDDP) to run a flat tappet will eventually exceed the benefits of the initial low cost. Besides, it's kind of a pain in the *ss to have to order special oil all of the time IMO.

I was also reading about going with the HR cam, but solid roller lifters. It's supposed to amount to super quiet running and no frequent lash adjustments. Thoughts, opinions, suggestions? I'm already planning to use lighter rod and pistons. It seems like a flat cam would just be holding it back.

 

[tc1959]

I have a hydraulic roller and roller rockers in my SBC for 10 years now. haven't had to readjust anything .
Been using Mobile one sense it was new. Only put a couple of thousand miles a year on the car.
Not a lot of expense changing oil .
I think with the roller set up it's pretty much bulletproof as a driver .

 

[G-Body_Vet]

I have a hydraulic roller and roller rockers in my SBC for 10 years now. havent had to readjust anything .
Been using Mobile one sense it was new. Only put a couple of thousand miles on the car, a year. Not a lot of expense changing oil I think with the roller set up it's pretty much bulletproof as a driver .

That's pretty much what has me leaning towards going roller. I want a low friction valvetrain, throttle response, no cam break-in required, no special oil additives and NO HEADACHES!

 

[79GP6.6L]

There is a difference between running a roller in a chevy engine and running one in a pontiac engine. I understand your reasoning, but I don't see a pontiac mechanical roller being as headache free as you say. How big of a cam are you thinking of using?

 

[Dr. Rudy]

Anyone know of any significant differences between solid roller lifters or hydraulic roller lifters performance or maintenance wise? Ive always wondered because a solid roller lifter shouldnt wear like a regular solid lifter.

 

[G-Body_Vet]

There is a difference between running a roller in a chevy engine and running one in a pontiac engine. I understand your reasoning, but I don't see a pontiac mechanical roller being as headache free as you say. How big of a cam are you thinking of using?

I'm not interested in a hyd roller for the sake of a big cam. I did all my homework for the flat tappet I wanted to run and that was a Crower 60919. I'm looking at a hydraulic roller, not a mechanical roller. I'll be running about 9.7 to 1 CR with my set-up and I want to keep the dynamic compression under control to avoid detonation. I haven't looked at the specs on the rollers yet to make a decision on what would be a good grind to go with.

 

[tc1959]

There is a difference between running a roller in a chevy engine and running one in a pontiac engine. I understand your reasoning, but I don't see a pontiac mechanical roller being as headache free as you say. How big of a cam are you thinking of using?

I'm not interested in a hyd roller for the sake of a big cam. I did all my homework for the flat tappet I wanted to run and that was a Crower 60919. I'm looking at a hydraulic roller, not a mechanical roller. I'll be running about 9.7 to 1 CR with my set-up and I want to keep the dynamic compression under control to avoid detonation. I haven't looked at the specs on the rollers yet to make a decision on what would be a good grind to go with.

I am running 9.5 to 1 CR with EGR. I still had to get a adjustable vacuum advance and play with the mechanical advance ,To get rid of full throttle pinging on Reg unleaded. It took a little tweaking but this roller set up works very well for a street driven cruiser. 8)
It made 385 HP at the crank with a reworked Q-Jet . If I were going to go Racing I think I would go with the solid roller set up ,but not on a Street car.
There is something to be said for durability and ease of maintenance.
Especially when you get to be and old man. :lol:

 

[67rstbkt]

There go the costs....adding up, lol. I was originally going to go with a standard hydraulic in my Poncho, but the machine shop talked me into an old-school solid. He reasoned that the routine adjustments are a good thing and would encourage me to have a look under the valve covers from time to time. They are also much more consistent, the valvetrain can only take one route over and over, compared to the variations possible with a hydraulic. The one thing I would look at if you are going to go roller is the lifter valley area. It's a weak part of the Pontiac and may be put under increased stress with the bulkier parts associated with a roller. You may want to look into one of those lifter bore braces; I added one just for a little extra insurance on mine, even though I m not doing a roller.

 

[G-Body_Vet]

There go the costs....adding up, lol. I was originally going to go with a standard hydraulic in my Poncho, but the machine shop talked me into an old-school solid. He reasoned that the routine adjustments are a good thing and would encourage me to have a look under the valve covers from time to time. They are also much more consistent, the valvetrain can only take one route over and over, compared to the variations possible with a hydraulic. The one thing I would look at if you are going to go roller is the lifter valley area. It's a weak part of the Pontiac and may be put under increased stress with the bulkier parts associated with a roller. You may want to look into one of those lifter bore braces; I added one just for a little extra insurance on mine, even though I m not doing a roller.

Yeah.....Kinda hard to avoid the costs huh? I guess you gotta pay to play though! 8)

I read about the lifter valley ordeal before too. The guy that rebuilt & ported my heads was trying to talk me into going to a solid cam as well.

The more I think about this, the more I want to get away from old tech and go with a modern valve train. It should make for a nice engine with a balanced & lightened rotating assembly. The idea of being obligated to buy additives or special oil for a FT cam doesn't sit well with me either. It's more expensive, then there's shipping costs if no local places have it.....and who knows when the gov't will come up with more senseless regulations?

 

[khan0165]

... again, I know SBC is not compairable to Pontiac, but I'll add my $0.02
I am currently on my first Solid flat tappet cam, and I don't think I can ever go back to Hydraulic.

the torque and throttle response is instant! And tuning is a dream, cuz the cam power range coming on thru the rpms is clear as day!
... yes adjustments are a pain, but it does make you more familiar with your engine. And a solid cam communicates engine behavior more clearly.

in my studdies of Pontiac motors... the lifter bores are a concern when running roller cams. And this is because of the aggressive ramp angle on the cam lobes. It just puts too much shock load on the the lifter bores.

You might be okay with a mild roller cam however.

... and a question from me is: how often do solid roller cams need to be lashed? I would imagine not as often as solid flat cams?