Solid Roller of Flat Tappet?

General engine tech -- Drag Racing to Circle Track

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cjperformance
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Re: Solid Roller of Flat Tappet?

Post by cjperformance »

Ok, but before you spend good money on .875 lifters get your lifter bores checked for alignment and size by a good shop (if you dont have access to this gear).
If you have a lifter bore out of alignment you will kill SR lifters really quickly no matter how good everything else is.
If your lifter bores are 110% then .875 will be ok, but if not you then need to see what is more viable, sleeving any bad bores to .875 or machining the lot to.903
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Re: Solid Roller of Flat Tappet?

Post by nickpohlaandp »

cjperformance wrote: Fri Oct 20, 2017 7:41 pm Ok, but before you spend good money on .875 lifters get your lifter bores checked for alignment and size by a good shop (if you dont have access to this gear).
If you have a lifter bore out of alignment you will kill SR lifters really quickly no matter how good everything else is.
If your lifter bores are 110% then .875 will be ok, but if not you then need to see what is more viable, sleeving any bad bores to .875 or machining the lot to.903
The machine shop I’ve decided to use seems pretty familiar with BBF builds, and ensuring lifter alignment. It was looking bleak for a while because the first few shops didn’t seem to know what I was even talking about when I brought up checking lifter alignment. Two of the shops told me they “think” they could install 4 bolt main caps. Not really a warm fuzzy when your machinist is timid to do a particular type of work. Finally found these guys, a few hours drive, but I’ll do the drive to get the work done right.
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Re: Solid Roller of Flat Tappet?

Post by KnightEngines »

Don't use conical springs.
Use a good regular spring (PAC, Isky) & Ti retainers.
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Re: Solid Roller of Flat Tappet?

Post by nickpohlaandp »

KnightEngines wrote: Fri Oct 20, 2017 8:29 pm Don't use conical springs.
Use a good regular spring (PAC, Isky) & Ti retainers.
Why do you say that? I’ve heard nothing but good things about conical springs?
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Re: Solid Roller of Flat Tappet?

Post by KnightEngines »

Nothing but good things - from amateurs that have them & want to feel good about their decision.
Talk to a few Pro's that know what they're doing - not many will tell you to run a conical over a good regular spring with a Ti retainer in your application.
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Re: Solid Roller of Flat Tappet?

Post by cjperformance »

Conical is only one spring/wire, if it breaks its goodbye engine almost certainly. With a dual+damper or triple then you're more likely to observe a problem before dropping a valve. Yeah single/conical is easier to make lighter but for durability you're better , IMO, with the smallest diameter lightest dual spring you can get that will do the job.
You'll get 100 differing opinions on this, thats just mine.
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Re: Solid Roller of Flat Tappet?

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KnightEngines wrote: Fri Oct 20, 2017 8:38 pm Nothing but good things - from amateurs that have them & want to feel good about their decision.
Talk to a few Pro's that know what they're doing - not many will tell you to run a conical over a good regular spring with a Ti retainer in your application.
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Re: Solid Roller of Flat Tappet?

Post by nickpohlaandp »

cjperformance wrote: Fri Oct 20, 2017 8:40 pm You'll get 100 differing opinions on this, thats just mine.
I like that, seriously! I like opinions better than “fact” when there are so many other factors in play. I honestly hadn’t thought about breakage and single spring, but you bring up a damn good point. It sure would suck to break a spring and dork up a $1500 head. Duals could certainly give you a “heads up”
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Re: Solid Roller of Flat Tappet?

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Yes well "fact" is that both spring types will work and do the job, and you may never have a problem with either!
I just like the saftey side of having the extra coil in there!
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Re: Solid Roller of Flat Tappet?

Post by KnightEngines »

Yeah, with a dual if you break one of the coils you'll still bend a valve & dent a piston, maybe some other assorted damage, but far less likely to be terminal.
With a conical the same can happen, just breaking the spring does not automatically mean you'll drop the valve & bust shit up real good - but there is a higher chance.
With a dual you have 2x springs to fatigue & they rub each other which helps with surge (they self damp to a degree) etc. Conical "generally" fatigue faster (shorter life span in the same application given equal quality materials), so life span is reduced. The theory is that a conical won't need damping as the change in dia *should* stop an tendancy towards harmonic surge, but the practice says the double does it better.

Conicals have their place in moderate hyd roller street engines, but are not suited to what you want to do.
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Re: Solid Roller of Flat Tappet?

Post by nickpohlaandp »

KnightEngines wrote: Fri Oct 20, 2017 8:59 pm Yeah, with a dual if you break one of the coils you'll still bend a valve & dent a piston, maybe some other assorted damage, but far less likely to be terminal.
With a conical the same can happen, just breaking the spring does not automatically mean you'll drop the valve & bust shit up real good - but there is a higher chance.
With a dual you have 2x springs to fatigue & they rub each other which helps with surge (they self damp to a degree) etc. Conical "generally" fatigue faster (shorter life span in the same application given equal quality materials), so life span is reduced. The theory is that a conical won't need damping as the change in dia *should* stop an tendancy towards harmonic surge, but the practice says the double does it better.

Conicals have their place in moderate hyd roller street engines, but are not suited to what you want to do.
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Re: Solid Roller of Flat Tappet?

Post by KnightEngines »

Same.

I'll use them in a pure street engine with a moderate hyd roller (like an LS or whatever), but as soon as things are getting a bit more serious I go to a regular spring.
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Re: Solid Roller of Flat Tappet?

Post by nickpohlaandp »

KnightEngines wrote: Fri Oct 20, 2017 9:24 pm Same.

I'll use them in a pure street engine with a moderate hyd roller (like an LS or whatever), but as soon as things are getting a bit more serious I go to a regular spring.
Well I believe the AFR’s I’m going to use come with PAC springs and Ti retainers, so that makes things easier.
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Re: Solid Roller of Flat Tappet?

Post by Steve.k »

557 iron headed cj with flat tappet cam 845hp! 4years running in mud truck zero issues.
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Re: Solid Roller of Flat Tappet?

Post by nickpohlaandp »

Steve.k wrote: Sat Oct 21, 2017 11:10 am 557 iron headed cj with flat tappet cam 845hp! 4years running in mud truck zero issues.
What kind of compression are you running though?
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