If I'm looking for maximum street driven horsepower in my 545 project, am I better off going with a solid flat lifter cam over a roller? I've heard a few stories about the reliability and longevity of the roller lifters. Heads will be out of the box SCJ's or P51's.
Roller cam or solid flat?
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Definitely flat tappet for reliable street use. Just be careful "breaking it in".
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What RPM range?
I'll be the odd man out.
What type of street driving ( hours, miles per year) if it's going to be limited I'd go solid roller. If guite a bit I'd still go solid roller and use Isky Red Zone lifters
http://www.iskycams.com/pdf/1-ISKYCatalog2009f_01Master Catalog2004 (Page 28).pdf
If you're not comfortable with that I'd have a custom hydraulic roller cam made for it before I'd do a solid flat tappet. Roller cams = hp
If I did do a flat tappet I'd not use the heads out of the box, get a little bit of work done on them with what ever cam you use, it's money well spent.
G-
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Everyone is certainly entitled to their own oppinion but, this is a terrible situation for a roller cam when the lifters will never be changed or rebuilt for the life of a street engine.
Hydraulic roller lifters in a big block Ford, (unless it's a Boss), will be out-powered by a good solid lifter flat tappet camshaft EVERY time.
Major MAINTAINANCE and periods between them is the biggest deciding factor here.
Choose accordingly...
If maintance is the main issue then use the Isky Red Zone lifters on a nice solid roller.
G-
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I guess Im not seeing why Hydrolic rollers are a poor choice I have had a couple 302's one a 112K miles on it with never a problem. Can some one explain to me why they do not hold up in a 460 based engine?
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their longevity is not the problem. the size, or more precisely the height of the roller itself causes pushrod geometry issues. Smallblocks do not have this problem as their pushrod pinch is much more inline with the lifter bores.
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thanks for the info I never thought about it like that but that could be a issue.
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G-Code
"EVERYTIME" in a Big Block Ford includes:
1. any RPM range
2. considering comparative grinds, a hydraulic roller camshaft NEVER idles as well as a flat tappet. Also, considering the 37° maximum attack angle of the cam lobe upon the roller of the lifter, it will NEVER be as aggressive as a flat tappet, (especially without any valve lash), up to about .080" lifter rise; which also translates to LESS actual valve lifts with a hydraulic roller lifter than with a flat tappet; (considering that higher pushrod angularity).
It is evident that you have never actually tested any of the above where your conclusions are supposed.
Oppinions are great only when there are not facts against the oppinion; (although you are entitled to have them whether incorrect or not), ... apparently you need to learn about some actual FACTS concerning street sized roller vs. flat tappet camshaft idiocyncrasies.
Mis-information is already rampant on here.
Solid roller cams are different.
EDIT: There are instances where a hydraulic roller camshaft is used where a SOLID roller lifter is also used and lashed at a tight /004"/.006".
"EVERYTIME" in a Big Block Ford includes:
1. any RPM range
2. considering comparative grinds, a hydraulic roller camshaft NEVER idles as well as a flat tappet. Also, considering the 37° maximum attack angle of the cam lobe upon the roller of the lifter, it will NEVER be as aggressive as a flat tappet, (especially without any valve lash), up to about .080" lifter rise; which also translates to LESS actual valve lifts with a hydraulic roller lifter than with a flat tappet; (considering that higher pushrod angularity).
It is evident that you have never actually tested any of the above where your conclusions are supposed.
Oppinions are great only when there are not facts against the oppinion; (although you are entitled to have them whether incorrect or not), ... apparently you need to learn about some actual FACTS concerning street sized roller vs. flat tappet camshaft idiocyncrasies.
Mis-information is already rampant on here.
Solid roller cams are different.
EDIT: There are instances where a hydraulic roller camshaft is used where a SOLID roller lifter is also used and lashed at a tight /004"/.006".
And my first choice was:
" What type of street driving ( hours, miles per year) if it's going to be limited I'd go solid roller. If guite a bit I'd still go solid roller and use Isky Red Zone lifters"
As of yet has the OP stated what he plans on doing with it, how many miles per year etc.?
There are quite a few solid rollers running around on the street and more than a few do the Power Tour every year. I know a guy who did it with the Isky Red Zones with over 1,400 miles. Pulled them out and inspected them and put them back in.
Do you know the mechanical abilities of the poster? Do you know if whether or not he has the ability to pull an intake manifold and swap out standard roller lifters after some numbers of miles or hours?
Yes we are entiltled to our own opinions, you take a mechanical flat tappet and I'll take a mechanical roller and stomp it in the ground
to each their own. G-
The car most probably will not see alot of miles, it'll be a toy that gets played with on the odd weekend. Here are a few factors that may come into play with the choice of cam:
-Car is a 1966 Fairlane GT (buying some Crites fibreglass panels to lose some weight and subframe connectors to stiffen it up)
-I want as much Hp as I can get, but I don't want a motor that overheats every time I take the car for a run down the block.
-Idle quality doesn't bother me, I love a radical lumpy cam note.
-OEM block.
-It has standard weight forged internals, 4.500 stroke, 4.400 bore, H-beam rods, KB icon 39cc dish forged pistons. 10.7:1 cr. 98 octane pump gas.
-C6 Trans.
-3.5:1 9inch diff.
-Heads are to be SCJ or P51 (leaning towards P51)
-Hi-6TR Crane ignition with timing retard and rev limiter, LX-92 coil.
-Aeromotive A1000 pump, 13204 reg, 1150 dominator carb.
-Zex dominator 100-300hp perimeter plate nitrous system.
-No inlet yet, but wanting h429 victor style dom pattern.
-Not sure of the RPM limit, I'd want to keep it at whatever I'm advised is safe for what I've got inside the motor, and where it stops making its power. I can't just pick a number.
-I want the thing to be as maintenance free as possible.
-I don't want to contend with parts failure or be concerned about it all the time.
-Cost is a factor, budget is not shoestring, but certainly not huge.
-Car is a 1966 Fairlane GT (buying some Crites fibreglass panels to lose some weight and subframe connectors to stiffen it up)
-I want as much Hp as I can get, but I don't want a motor that overheats every time I take the car for a run down the block.
-Idle quality doesn't bother me, I love a radical lumpy cam note.
-OEM block.
-It has standard weight forged internals, 4.500 stroke, 4.400 bore, H-beam rods, KB icon 39cc dish forged pistons. 10.7:1 cr. 98 octane pump gas.
-C6 Trans.
-3.5:1 9inch diff.
-Heads are to be SCJ or P51 (leaning towards P51)
-Hi-6TR Crane ignition with timing retard and rev limiter, LX-92 coil.
-Aeromotive A1000 pump, 13204 reg, 1150 dominator carb.
-Zex dominator 100-300hp perimeter plate nitrous system.
-No inlet yet, but wanting h429 victor style dom pattern.
-Not sure of the RPM limit, I'd want to keep it at whatever I'm advised is safe for what I've got inside the motor, and where it stops making its power. I can't just pick a number.
-I want the thing to be as maintenance free as possible.
-I don't want to contend with parts failure or be concerned about it all the time.
-Cost is a factor, budget is not shoestring, but certainly not huge.
The cost to rebuild the motor after wiping the solid flat tappet cam on initial startup? $$$
You've got the motor and expectations that are definitely solid roller worthy. The questions are: Do you want to spend a little extra up front, and, are you willing to pull the lifters out periodically to have them inspected and\or rebuilt?
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It is a complete excercize in engineering which Ford Motor Company totally went through in 1990.
Will it work ... sure but, NOT BETTER; was it worth the extra cost ... NO.
An inline valve engine, (302 and such), has a valve train which is NOTHING like a canted valve engine with inline lifters.
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Seems as though you have had your mind mind made-up already so, why even ask...?
Just get your roiller valve train and experience it for yourself.
"Good judgement comes from experience and experience ... well, that comes from bad judgement", Ben Franklin
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"I know a guy who", My brother's friend has", "I read an article where" ... exactly how much testing of these scenarios have YOU actually performed? Not conjecture and second or third hand information but, gathering data though actual testing of your own accord.And my first choice was:
" What type of street driving ( hours, miles per year) if it's going to be limited I'd go solid roller. If guite a bit I'd still go solid roller and use Isky Red Zone lifters"
As of yet has the OP stated what he plans on doing with it, how many miles per year etc.?
There are quite a few solid rollers running around on the street and more than a few do the Power Tour every year. I know a guy who did it with the Isky Red Zones with over 1,400 miles. Pulled them out and inspected them and put them back in.
Do you know the mechanical abilities of the poster? Do you know if whether or not he has the ability to pull an intake manifold and swap out standard roller lifters after some numbers of miles or hours?
Yes we are entiltled to our own opinions, you take a mechanical flat tappet and I'll take a mechanical roller and stomp it in the ground
G-
I'm really curious ... along with everybody else here; by the number of PM's I've recently gotten.
" -I want the thing to be as maintenance free as possible.
-I don't want to contend with parts failure or be concerned about it all the time."
I don't see where he has his mind made up and it would seem from the words he typed above that he'd be leaning your direction with a solid flat tappet. I'd suggest you get your panties out a a bunch and start the day over.
G-
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