How does a solid roller cam act vs solid flat tappet

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MOPARMAGA

MOPARMAGA

" The other hard member"
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Hey there fabo friends, hopefully I'm going to ask this question correctly. Currently I'm still in the build process of my 471. The dude who is helping me out with my build really really wants me to buy a solid roller for my engine. However I already had planned out & purchased most of my parts around what my plan was. The cam I have now (still in the box & tube) is a howards cam, solid flat tappet with edm upgrade lifters & the proper springs for the required pressures. Besides the near $1800.00 to upgrade to a roller & the reduction of friction + the valves opening & closing faster, how would I chose basing on duration @ .050 ? Is a 260-264 @.050 solid flat like I have what I should shoot for in a solid roller or do the 2 cams act different.
I suppose I should call howards & ask them what the intake closing point is on the 2 cams I have in mind the one I really like has 258 or so intake 268 exhaust & .640 lift.
I don't want to over cam obviously & my compression numbers I can manipulate a little between 11.2 & 11.5.
Hopefully someone gets what I'm trying to ask. Thanks guys !
 
People are gonna need more details of your combo especially the heads and gearing, stall, intake etc.. car weight and purpose too.
 
273 said:
People are gonna need more details of your combo especially the heads and gearing, stall, intake etc.. car weight and purpose too.
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Yeah, I suppose.
 
It is best to ask this question to the cam manufacturer. They will ask you all of the pertinent questions about your combination and steer you in the direction of what will work best for you. They want you to get the best result, that is the best advertising they can get.
 
Okay the info I know as of now as in what I have.
Car 70 dart swinger, will be under 3000 with me in it
73 400 block.
Molnar crank 3.915 stroke
Rods undecided but have molnar billet 6.70 rods & speedmaster 6.70 with L-19 arp bolts.
Pistons flat top +6 cc SRP 4032 forged
4.375 bore
Trickflow 240 heads & track heat intake
Since I'm not transmission parts far into this I'd like to be under 4k on the stall
28-30 inch tires undecided
Gear 3.91 -4.30 undecided.
Billet steel drum
Manual valve body.
Purpose of car is to piss off libtards #1
#2 drive it to nearby shows
#3 (newly developed idea ) trailer it to the track which is going to be close by after the wife & I move. I'm looking to run 10s, won't be a problem but just 10s for $$$$$ sake & not have to get recertifications for parts & rebuy stuff for sfi sake
 
MoparLeo said:
It is best to ask this question to the cam manufacturer. They will ask you all of the pertinent questions about your combination and steer you in the direction of what will work best for you. They want you to get the best result, that is the best advertising they can get.
Click to expand...
Thanks yes I definitely plan too, I was just curious of real life experience since I'm sure there's plenty of it on here
 
IF! The roller cam has more aggressive lobes, then the same as a solid cam, just more aggressive. The same applies for the same lobes or smaller lobes. AKA, the same or less aggressive....

Is all in the lobes.
 
rumblefish360 said:
IF! The roller cam has more aggressive lobes, then the same as a solid cam, just more aggressive. The same applies for the same lobes or smaller lobes. AKA, the same or less aggressive....

Is all in the lobes.
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Andy f if you're out there, I was ready your bump sticks & carbs article.
The camshaft that Dwayne had made for you is in the ballpark of where I'm aiming.
Is that cam still in the 470, & is that the dustbin duster engine ? What stall converter did you use if that is the same cam
 
MOPARMAGA said:
Okay the info I know as of now as in what I have.
Car 70 dart swinger, will be under 3000 with me in it
73 400 block.
Molnar crank 3.915 stroke
Rods undecided but have molnar billet 6.70 rods & speedmaster 6.70 with L-19 arp bolts.
Pistons flat top +6 cc SRP 4032 forged
4.375 bore
Trickflow 240 heads & track heat intake
Since I'm not transmission parts far into this I'd like to be under 4k on the stall
28-30 inch tires undecided
Gear 3.91 -4.30 undecided.
Billet steel drum
Manual valve body.
Purpose of car is to piss off libtards #1
#2 drive it to nearby shows
#3 (newly developed idea ) trailer it to the track which is going to be close by after the wife & I move. I'm looking to run 10s, won't be a problem but just 10s for $$$$$ sake & not have to get recertifications for parts & rebuy stuff for sfi sake
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1. Going to be hard to get under 3000 with driver, unless you are about 100 pounds LOL. If you can get it that light, good on you, because that’s tough.

2. You already have the solid set up. I’d run it. Get your ducks in a row on start up and you’ll be fine.

3. I’d use the 4.30’s, but that’s me.

4. I use PTC for converters. Call them and let them pick the converter. I just did a 400 Chevy tunnel ram deal and used a PTC converter they spec’d. 8 inch case, 8 inch stator. It’s a converter they use for drag week. In this car it stalls at a bit over 5100 and drives better on the street than the junk 3800 converter that it replaced.

That’s what I’d do. Don’t skimp on gear or converter. That’s the two biggest combo killers there are.
 
yellow rose said:
1. Going to be hard to get under 3000 with driver, unless you are about 100 pounds LOL. If you can get it that light, good on you, because that’s tough.

2. You already have the solid set up. I’d run it. Get your ducks in a row on start up and you’ll be fine.

3. I’d use the 4.30’s, but that’s me.

4. I use PTC for converters. Call them and let them pick the converter. I just did a 400 Chevy tunnel ram deal and used a PTC converter they spec’d. 8 inch case, 8 inch stator. It’s a converter they use for drag week. In this car it stalls at a bit over 5100 and drives better on the street than the junk 3800 converter that it replaced.

That’s what I’d do. Don’t skimp on gear or converter. That’s the two biggest combo killers there are.
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Thanks yellow rose for straight shootin.
I will talk with pct they're Florida based correct? I think I can get 3k with time, aluminum & my tig welder
 
roller gets the ramp up faster than a flat tappet cam, and gets it down faster so you have more open time at max lift where it flows better. also reduced friction and can be reused. the flat tapped it restricted on how fast it can actually open a valve by its design. Sort of like the difference in area of a triangle (flat tappet lifter profile) and of a square (roller profile) more area means more flow.
 
pishta said:
roller gets the ramp up faster than a flat tappet cam, and gets it down faster so you have more open time at max lift where it flows better. also reduced friction and can be reused. the flat tapped it restricted on how fast it can actually open a valve by its design. Sort of like the difference in area of a triangle (flat tappet lifter profile) and of a square (roller profile) more area means more flow.
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Really good explanation
 
pishta said:
roller gets the ramp up faster than a flat tappet cam, and gets it down faster so you have more open time at max lift where it flows better. also reduced friction and can be reused. the flat tapped it restricted on how fast it can actually open a valve by its design. Sort of like the difference in area of a triangle (flat tappet lifter profile) and of a square (roller profile) more area means more flow.
Click to expand...
I suppose that answers part of my question, the same duration would act different between cams.
 
MOPARMAGA said:
I suppose that answers part of my question, the same duration would act different between cams.
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Touching more on that. It depends on where the duration is measured. An advertised duration of say 290 flat vs roller would have different @.050 duration. Since the ramp is quicker on a roller.
 
I'm building a 470 to and yours sounds about the same as mine. Dwayne spec'd a cam out for me last week it's a roller he suggested to use a converter with 5k stall because I'll be using 4.30 gears and a 29 inch tall tire but I'm driving a B-body
 
mini said:
Touching more on that. It depends on where the duration is measured. An advertised duration of say 290 flat vs roller would have different @.050 duration. Since the ramp is quicker on a roller.
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Yeah, I pretty much only look at .050 since advertised is worth much in comparable term with other cam manufacturers
 
67mprfan said:
I'm building a 470 to and yours sounds about the same as mine. Dwayne spec'd a cam out for me last week it's a roller he suggested to use a converter with 5k stall because I'll be using 4.30 gears and a 29 inch tall tire but I'm driving a B-body
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I think I maybe okay with 4k. If I go with 29
Tire, what size tire is that 29?
 
Remembering reading somewhere solid cams can have faster ramps then solid roller depending on duration, I wouldn't just assume they have faster ramps.

For what you said you want the cam you have is probably good enough, didn't see the specs of it.
 
273 said:
Remembering reading somewhere solid cams can have faster ramps then solid roller depending on duration, I wouldn't just assume they have faster ramps.

For what you said you want the cam you have is probably good enough, didn't see the specs of it.
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260-264 @.050 .616-.620 108 lsa
 
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