351 W Question

[poboys 94]

Hey guys been a while since I been on here, finally back to work after long recovery so Im again able to mess around with the car. Anyway, I was thinking of going 347 but my new job has given me some good contacts and I might be able to swing some deals and go 351 I just need to know which late model blocks support roller lifters, Thanks in advance

 

[BlackVert]

I think the earliest late model block that supports HR lifters is 1994. Not 100% sure though, so don't quite me on it.

 

[madams74]

Any block will support roller lifters. To use a pre roller block you have to add dogbones to roller lifters, a spider support, and small circle base camshaft. The most work is done in drilling the block for the spider support. I used heli-coils in the block and added studs. you can see the nuts and washers, which are loc-tited in the engine. The areas around the dog-bones had to be slightly modified using a porting tool, to allow them to fit evenly.

 

[BlownFiveLiter]

You can go that option ^ or run the link-bar lifters and not sacrifice power by running a small base circle cam.

Edit: I'm referring to using a non-roller block of course.

 

[final5-0]

I was thinking I saw some concerns with running a roller cam in a non roller
block.

I really don't know or remember all the details but some how or the
other ... a red flag of caution pops up in the back of my feeble mind
when I think of the application

For a street combo ... where the rpm's usually are kept at a reasonable
limit ... it might not make any difference anyway

Grady

 

[poboys 94]

The expense of the kit is what Im trying to avoid. There are some salvage yards one close by that have 351s out of late model vehicles and the money saved from that will go towards the carb swap parts
So any 351 out of a 94 on up will do?

 

[BlackVert]

a small base circle cam is not a good idea for a couple of reasons. (1) your options are much more limited, as 99% of the cams are not small base circle based, and (2) read this:

http://bbs.hardcore50.com/vbulletin/showthread.php?t=37449

fwiw, i am Chris Curl, the guy who started that thread over there

bottom line: don't go with a small base circle cam

 

[madams74]

Ignorance is bliss. You guys have no idea what your talking about. A Thumpr cam from Comp has as much usability as any of the Ford series cams that 90+% percent of all the people reading this have installed. Do not go telling people that small circle base cams are a BAD idea. Thats like telling people not to stroke a 302 to a 347 and just go with a 331 due to longevity problems. It is a FACT that small circle base cams are just as reliable and trusting as a regular roller! If you were not so against them, you would know from shopping that the options are out there to find one to meet almost anyones street needs.

 

[blksn955.o]

Some 94's did not get roller 351 blocks either depending on production date/luck...some of the gen1 lightning guys with 94's do not have roller blocks. It seemed to be more hit or miss with the 94's.

The casting number for roller 351 blocks is F4TE. It should be around the starter location IIRC. The roller blocks are not as strong as the early 70's 351 non rollers but should still be good for around 600rwhp.

 

[poboys 94]

F4TE, thanks

 

[BlownFiveLiter]

Ignorance is bliss. You guys have no idea what your talking about. A Thumpr cam from Comp has as much usability as any of the Ford series cams that 90+% percent of all the people reading this have installed. Do not go telling people that small circle base cams are a BAD idea. Thats like telling people not to stroke a 302 to a 347 and just go with a 331 due to longevity problems. It is a FACT that small circle base cams are just as reliable and trusting as a regular roller! If you were not so against them, you would know from shopping that the options are out there to find one to meet almost anyones street needs.

On the contrary, I do know what I'm talking about, and there does come a point where you are going to sacrifice power with a small base circle cam. You can only undercut the base circle so much before you do start to run out of options, especially if you want, or need to run a high lift cam. Ok, so you have a small base circle, but you need something like .600 lift on your cam. Then what? You're still going to have your standard hydraulic lifter coming too far out of the bore, exposing the oil hole and starving it of oil. That is only a theoretical lift number above, since I don't feel like looking up the max lift on a standard cam with hydraulic lifters in a non-roller block, versus running them in a non-roller with a small base circle cam, but the point is, running the link-bar lifters is still a better idea. In most street combinations, running a small base circle will probably be perfectly fine, but it does limit your cam choices, in the way of being able to pick up something halfway decent off the shelf.

 

[madams74]

In most street combinations, running a small base circle will probably be perfectly fine, but it does limit your cam choices, in the way of being able to pick up something halfway decent off the shelf.

Everyone wants to stick a feather in their hat when they pounce of the scum bags like me who are here to serve the reality of this forum and the majority reading it. You have a ton of kids on here and newbies who are dipping into their parents pockets for just a chance to show their friends whats new under the hood, and your rejecting the very basis of what we all started this forum to do. It IS about education, and right from wrong, but NOT to make statements steering people away from a choice INDEFINITELY based on an unholy, unrealistic lift that most of the small base cams stay clear from. Your comment quote from above is the truth, and I am glad you see it this way. IN MOST STREET COMBINATIONS, RUNNING A SMALL BASE CIRCLE CAM SHOULD BE PERFECTLY FINE. So there we have it. The truth............now no one will freak out when their engine builder mentions this option or they see it in catalog and turn their nose at it. We have to base our responses on facts so everyone can make up their mind. An option you opted to float slightly in your first views on this. I was not trying to insult your intelligence sir. Link bars are fine, but so are small base circle cams. If you would shop for the numbers you would see that most of them never reach more than .550 anyway. So there you have it for anyone using the search option on this in the future. You do have a choice other than $400 link bars that works, is affordable, and fine for your daily driving needs and not a 7 second NHRA car. Good day.

 

[BlackVert]

Ignorance is bliss. You guys have no idea what your talking about.

geez, i feel like i'm on corral or something.

if you happened to read the thread i referred to, you would notice that all i did was ask the question and then stepped aside to let people provide their insight into it. also notice that i asked the question over on hardcore, not here, because the people on hardcore in general have alot more experience building fast cars than many other places. after all, over there, you have ed curtis, jay allen, george klass, mark o'neal, and a host of other guys who do this stuff day in and day out.

i am the first one to admit that i do not have enough experience with it to be able to provide first hand knowledge on the topic, but i specifically asked the question about small base circle cams, and i was doing the right thing by referring the original poster to the information i learned about small base circle cams.

so, it is not clear to me who the ignorant one is

 

[BlownFiveLiter]

Do you really think an NHRA tech engineer is reading your reply to suffice whether to run a .600+ lift cam on Stangnet for his engine build?

No, I don't. An NHRA tech already knows what's going to make power and isn't on StangNet asking for advice.

You have a ton of kids on here and newbies who are dipping into their parents pockets for just a chance to show their friends whats new under the hood, and your rejecting the very basis of what we all started this forum to do. It IS about education, and right from wrong, but NOT to make statements steering people away from a choice INDEFINITELY based on an unholy .600 + lift.

I'm not rejecting anything. What education have you provided thus far, aside from making a statement for Comp Cams Thumpr series cams, with zero supporting evidence to substantiate your claim? Do you have a small base circle cam? Got some specs on it? How about a dyno sheet? I stated pretty clearly that the .600 figure was a theoretical number, by the way.

I'm not trying to start a pissing match, but what if one just wants to build an engine and found the "perfect" cam, in their eyes? What if it happens to be an off the shelf grind? Do they take those cam specs and have it ground on a small base circle? The guys running the 7 second 1/4 mile passes have just about infinite money to throw at their engine to keep it competitive in their respective classes. Most of us don't have money to throw at custom grinds, fancy CNC port jobs, aftermarket blocks, etc., and can't chance building an unreliable engine that may grenade the first time we run it.

You and I both know there's a lot more to a cam than peak lift, so I don't see a reason to argue that point at all. I was making an attempt to point out that even if you were to undercut the base circle, say .100 to accommodate the lifters, you still have to take into account that the max lift still needs to be kept below a certain point, or you're going to expose the oil hole and bleed out the lifter. Then it's as good as useless because you now have no lift. The .600 figure was, as I stated, just a theoretical number, but I think the max lift does come out somewhere around that figure when using hydraulic roller lifters on a small base circle, in a non-roller block. You might need that extra lift when feeding large cubes. Here's another way to look at it: Buy the $400 link bar lifters and $150 off the shelf grind, for a total of $550, or spend $300 on a custom ground small base circle cam and $100 on hydraulic lifters. For that extra $150, you don't have to worry about peak lift affecting your lifters, aren't going to expose your oil holes on the lifters, don't even have to worry about drilling into your cam bearings, if you drilled too deep when trying to tap the valley for the spider. It's personal preference. Me, I'd spend the $150 extra.

 

[madams74]

You sure your a Republican StangGT1995 ?? Your swimming like a lib. HE HE No seriously though, I see your points, and I only wished that all the options were laid out in the first place. Ignorance is Bliss, to me, means that sometimes it is easier to just eliminate the doubts and stick with the obvious. In your case you knew about the facts of small circle base cams, and opted to eliminate some of the truths on them. Your a pretty fart smeller in my book!! We cool??

 

[BlownFiveLiter]

Of course we're cool! We just might as well get all of the pros/cons out of the way when getting into the discussion, right? Now if only I could afford a 351 based combo, to even have to worry about that decision...

 

[BlackVert]

Your a pretty fart smeller in my book!!

insults are not taken lightly here, nor should they be.

 

[BlownFiveLiter]

I believe he was saying I've smelled the roses, not throwing an insult my way.

 

[BlackVert]

ok then, i retract my statement

 

[1slow95]

Everyone wants to stick a feather in their hat when they pounce of the scum bags like me who are here to serve the reality of this forum and the majority reading it. You have a ton of kids on here and newbies who are dipping into their parents pockets for just a chance to show their friends whats new under the hood, and your rejecting the very basis of what we all started this forum to do. It IS about education, and right from wrong, but NOT to make statements steering people away from a choice INDEFINITELY based on an unholy, unrealistic lift that most of the small base cams stay clear from. Your comment quote from above is the truth, and I am glad you see it this way. IN MOST STREET COMBINATIONS, RUNNING A SMALL BASE CIRCLE CAM SHOULD BE PERFECTLY FINE. So there we have it. The truth............now no one will freak out when their engine builder mentions this option or they see it in catalog and turn their nose at it. We have to base our responses on facts so everyone can make up their mind. An option you opted to float slightly in your first views on this. I was not trying to insult your intelligence sir. Link bars are fine, but so are small base circle cams. If you would shop for the numbers you would see that most of them never reach more than .550 anyway. So there you have it for anyone using the search option on this in the future. You do have a choice other than $400 link bars that works, is affordable, and fine for your daily driving needs and not a 7 second NHRA car. Good day.

When I was building my engine Ed Curtis told me stay away from the roller conversion and go with the link bars. And my cam has .600" lift, BTW.