Difference between solid roller and flat tappet

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B3422w5

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Any opinions on horsepower difference on a eddie stroker between a fairly healthy flat tappet And a roller cam in the same ballpark?
 
I say, come at it from a different perspective.......

How much difference in power would there have to be for you to make the plunge?
And then....... does that difference seem like a plausible number?

Also, where you are on the mild-aggressive lobe scale can be a big player here.
A very aggressive SFT can easily out power a very mild SR.
 
I have no idea how agressive the lobes on the Howards 260/264 cam i now have is. So dont really know how to compare.
Taking my stuff up to the shop that did the dyno competition winning stock stroke 360 this afternoon.
Gonna look over my shortblock and heads, see if my intake i am gonna use( excellerator) needs milled because heads were a while back etc.
 
I've always been budget minded... and its always been cheaper to self educate than spend needlessly.
I agree with PRH. there are several aggressive 904 profiles that can go nose to nose with a roller.
Compare duration at .200. That is usually the breaking point. In fact, if the Mfg doesn't list dur@.200, I move on, just for that reason.
 
Don't forget the Hughes Engines way. They have some very light weight flat tapped lifters they say can make some of their solid camshafts on par with a roller. It wouldn't surprise me. I agree with the budget comment, of course...LOL...BUT you also cannot overlook the differences in durability and wear with a roller versus a flat tappet. It's gonna all boil down to what you want. I know at this point, if I had the extra money I would build a solid roller motor. You only live once. But that's me in the now and IF I had the money. I don't.
 
I think it also depends on if you are at the limit of what HP your heads can support. If you are already taking advantage of the flow potential then you probably won't see much gain, if any (just my guess).

Not an apples to apples comparison, but the only one I have from personal experience. My old 410 stroker motor ran a small solid roller from Comp (248/254 @ 0.05 with about 0.576 lift) and 10.8:1 compression ran 10.7-10.8 on typical warm summer days. My new 408 stroker (same heads/intake/carb/etc.) has a larger solid flat tappet from Hughes (264-268 @ 0.05 with about 0.620 lift) and 13:1 compression runs 10.3 on warm summer days....so 4-5 tenths difference using a bigger cam and more compression (the rest of the combo was the same between the 2 engines).

Not sure if that is helpful at all since it is not a like for like comparison, but its all I have. My guess (if I were to make one) if you have an aggressive FT cam, you probably aren't missing out on too much HP....maybe 10-15 ish??
 
I say, come at it from a different perspective.......

How much difference in power would there have to be for you to make the plunge?
And then....... does that difference seem like a plausible number?

Also, where you are on the mild-aggressive lobe scale can be a big player here.
A very aggressive SFT can easily out power a very mild SR.
Dwayne, r u comparing the same specs for both cams? Thanks. Kim
 
Heading up to drop the stuff off now.
The heads are very lightly ported right now.will see what gains are possible keeping in mind my current cam with some more work on them.
 
Too bad you can’t get mushroom lifters any more. I’d do that in a heartbeat if I can get them.

I used to resurface those, back when I was working... sadly, I don't have access to that anymore.
There used to be a local shop (to me) that could do it but, it's changed hands since.
Now if you ask a shop, they look at you like you're asking for a unicorn !
 
For a race car, where lifter life on the street isn’t a concern....... my preference would pretty much always be to use a roller.
 
Well, dropped my stuff off.
Pistons poke out enough gonna need a Cometic gasket. Either a 45 Or 51. Looks like they are close to 10 out.
I had the heads worked a little by a local guy several years back to pick the car up enough to run 11.50 index in dead of summer heat.
We then sent them to the local NAPA to have them milled enough to with a thin gasket(028) raise the compression up.
The pistons were 30 down in the old 360.
Well, first thing Jack noticed with my heads was the intake valves were super shrouded. He said there was 20 horse just fixing that. Said the chambers were the real key with Eddie heads.
I asked, after he looked at them what he guesstimated they might flow. He said 255-260, just taking a quick look.Less than i had suspected.
Anyhow, going from 360 to 418, 10 to 12.5 ish compression, the head work he is going to do( nothing super involved, said maybe 275-280 max) Fresh, quality valve job, nice single plane, vice the old airgap, an 80 horse gain wouldnt be out of the equation.
I ran a “ new” cam Howards now offers by him, its 268/274, 630 ish, 640 ish with my 1.5 rockers. Current is 260/264 565/565. Both are on a 106... that big one would sound ultra choppy.... i like choppy..lol
Before doing that, we will flow the heads and see if as he put it... “if they are still pulling at 600“. Otherwise just put the old cam back in and call it good( more than likely what I will do for now) we will see... might need different springs, etc to do that
 
Inquiring minds would love to know. I’ve kicked the idea of going with a roller cam has been bouncing off my brain for five years. My 422 with a 650 solid lifter cam has gone 5.98@113 mph in the 1/8 and 9.42@138 (2860 pounds) in the 1/4. It’s getting rebuilt this winter after five years of zero issues engine wise. My sons stock stroke 360 (3200 pounds) with a 610 lift roller ran 6.54 four different times but broke a Comp Cams roller lifter bar with 50 runs on them trashing the whole engine. Hmmmmm trouble free, NO. Things like this can cause a few sleepless nights. The 360 short block I have done on my engine stand has a roller cam. The 408 short block I have finished for the start of next year has a roller cam. It will be an interesting Winter for sure.
 
The way I see it is.......

I figure for every roller cam combo that failed a lifter, there’s at least one flat tappet cam combo that chopped a lobe.

**** happens.
 
The way I see it is.......

I figure for every roller cam combo that failed a lifter, there’s at least one flat tappet cam combo that chopped a lobe.

**** happens.


To this I will agree but and a big BUTT when you wipe a solid lifter cam how many get away with just throwing another cam in it. My son just ran a 6.56 and driving the 1/2 mile back to the pits heard a noise. The engine was toast. Gone, kaput, end of story, the fat lady sang.
 
To this I will agree but and a big BUTT when you wipe a solid lifter cam how many get away with just throwing another cam in it. My son just ran a 6.56 and driving the 1/2 mile back to the pits heard a noise. The engine was toast. Gone, kaput, end of story, the fat lady sang.

heard your kids name mentioned Thursday by the announcer at the million dollar race At Memphis. Think they know each other
 
heard your kids name mentioned Thursday by the announcer at the million dollar race At Memphis. Think they know each other


Hmmmm wonder who was announcing. We are friends with both announcers at Norwalk. My Kid gets around and will drive anything so I’m not sure who that would be. Have helmet will travel. Lol. Matt headed to Quaker City this weekend.
 
Hmmmm wonder who was announcing. We are friends with both announcers at Norwalk. My Kid gets around and will drive anything so I’m not sure who that would be. Have helmet will travel. Lol. Matt headed to Quaker City this weekend.

not sure....
The tape is on motor mania... pretty sure it was thursday. Whoever the announcer was, i got the impression he raced in Ohio a good bit
 
I have no idea how agressive the lobes on the Howards 260/264 cam i now have is. So dont really know how to compare.
Taking my stuff up to the shop that did the dyno competition winning stock stroke 360 this afternoon.
Gonna look over my shortblock and heads, see if my intake i am gonna use( excellerator) needs milled because heads were a while back etc.
I think that cams lobes are fairly aggressive they are .904 lobes
 
For a bracket car I’m not sure I would chase the last bit of ET by going roller unless you really need to. They both can fail, but the feeling I have is a SFT failure is most likely an attention to detail thing. While a SR seems always to have a life span that starts from day 1 and goes to............ouch! Yesterday! That being said certain classes put you in such a box a roller is the ticket. I’m sure one is in my future. Just have to get appropriations to agree! :)
 
For a bracket car I’m not sure I would chase the last bit of ET by going roller unless you really need to. They both can fail, but the feeling I have is a SFT failure is most likely an attention to detail thing. While a SR seems always to have a life span that starts from day 1 and goes to............ouch! Yesterday! That being said certain classes put you in such a box a roller is the ticket. I’m sure one is in my future. Just have to get appropriations to agree! :)

Good points. I am looking at this thing being able to run 11 flat in real bad air. If it does that, it will meet my goal.
 
Too bad you can’t get mushroom lifters any more. I’d do that in a heartbeat if I can get them.

They are still being made...maybe CVR? Ill think of it....

Mike Jones told me with a .904 lifter you can come within an inch of a rollers performance with a flat tappet cam.
 
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