Well, I’ve finally found the time to pull my engine AGAIN – this time because of a leaking 2 piece rear seal. After looking over the entire engine, that was the ONLY thing that was leaking. Not one drop of oil/coolant anywhere else! Figures…but since I went through the hassle of yanking this thing out again…….it’s finally time to convert to a roller cam! I *THINK* I have all the parts I need. I’ve had these parts in standby for over a month now:

-Comp cam XR288 custom ground with a small base circle
-Comp valve springs, retainers (for roller cam)
-Lunati retro roller lifters
-Comp hardened pushrods
-Melling timing cover w/thrust button/gasket
-new screw in rocker studs
-Oil pan gasket
-intake gasket
-Comp hardened fuel pump pushrod
-new rear seal too!!!

** Please feel free to chime in if you think I’ve overlooked something…

I’ll be reusing my Crane roller tip rockers, valve keepers, and timing gears and chain since they’re pretty new anyways. I’m assuming these parts are the same between flat tappet and roller. I’m considering getting rid of the poly locks I have for the rockers and just use standard locknuts. But that might come later.

I’ll post occasional pics on the progress so maybe this thread will be useful for someone else doing this….pics forthcoming!

 

Well since no one's chimed in yet saying I need anything else, I'll post a pic of the candidate:

 

Just yanked it out by myself Sat. evening. Clutch looked pretty worn to me for some reason....here's some of the parts goin in...that was a Cloyes timing chain cover - I stand corrected...

 

What do you think of the Cloyes cover? I thought about one but ended up getting the Comp instead.

 

The Cloyes seems pretty well made. It looks nice I think!

 

It doesn't look like you'd be able to do much through the cover except maybe change the timing.

 

Yeah, you're right. I don't plan on doing anything except slapping it on and checking the thrust on the cam. Other than that, I could've gotten away with using a thrust "button" instead, with a water pump that has the reinforcing bolt in it. Call it a luxury item then! lol

 

Took off the intake, water pump etc. - Everything was looking great. Timing chain was still like new (should be). I then removed my roller tip rockers and I find 2 broken pushrod tips!!

Same thing I found last time I had it apart. I need to figure out what's causing this, but maybe it's a wash now that I'm installing new cam, lifters and pushrods anyway. I also have a "pushrod length checker I plan to try and use to double check the valve train geometry.

Oh, and I also pulled the spark plugs, which have less than 3K on them, and every plug thread had oil on it as I removed each plug. I don't know what that's about unless I'm using the wrong plugs. They all had a wettish tint and black - except for #6 plug for some reason?!? That one looked the most normal to me. Funny thing is, before I pulled this engine, it seemed to run great! That tells me there's more power to be had if I can tune this thing better...
Pics...

 

Looks like I might have a problem now, but I'm not sure. I hooked an air line up to my leakdown tester to hold the valves shut while I changed to the new bigger diameter springs that go with the roller cam. I noticed on the retainers I got with everything else, the hole in the center is bigger than the ones I'm replacing them with.

I tried to install one, and after I put the keepers on, the top of the valve stem is way BELOW the level of the retainer. The top of the stem is kinda sitting down inside the retainer. Is that normal for a roller valve train?

It kinda looks like the roller tips on the rockers will hit the retainers to me...or I need special keepers, I have wrong retainers or something...

Anyone heard of this?

 

Well, it won't let me attach a pic when editing on the last post, so anyways, here's a pic of the new spring and retainer (left) and the old one on the right. Is this normal?? It can't be. my roller won't even touch the valve tip like that. What gives??

 

You've got the wrong retainers.

 

Or the wrong keepers.... 10° retainers, and 7° keepers....

Always buy the keepers that go with the retainers you're running. Don't try to mix & match unless you're REALLY SURE of what you've got, all sorts of strange things can result from that.

I'd sure be trying to find out why it ate those push rods like that, before just putting it back together. That looks like the push rod was being forced out of its seat in the rocker, from hitting the side of hole in the head (probably facing the rocker stud) or something similar. Also check and make sure the rockers in question aren't damaged.

 

Now that's what I'm talking about! Thanks for the replies!

After my last post, I snooped around and I found out that Comp sold me thier "Super Retainers" (part# 740-16) and they require 10 degree locks!! So it seems Sofa nailed it! And you’re right, I tried to reuse the 7 degree locks (or keepers) on the new retainers, and that ain’t gonna work! (not intentionally)

But – I don’t know whether it will make that big of a difference. The valve tip is just that far down into the retainer….I plan to call Comp today and see what they say.

So far as the pushrod tips being broken like I said above, I had 2 broken ones when I checked it last time but I couldn’t find anything wrong. It’s funny because just like last time, all the other pushrods look fine, as well as all the rockers. No evidence anywhere of anything rubbing. I use guide plates, and Comps steel roller tipped rockers. I figure everything’s gonna change now when I change over to roller, so I’ll need to make sure I have everything right with the pushrod length checker and go from there. I’ll post up what Comp tells me…

 

OK, I called up Comp and gave them all my info AGAIN, and yeah, I need 10 degree locks. I'll order those tonight. I also asked him if the diff. between the 7 and 10 degree locks will allow the valve tip to be level/or above the retainers where they should be, and he claims it will....I'll see. Just doesn't seem to me that 3 degrees would make that dramatic of a difference.

OK - so about the only 2 things I'll have left from my flat tappet setup after this, will be my rockers and my timing gears/chain. Even though it may look like it, I really didn't go into this blindly. I did do what I thought was enough research into the conversion. But I know a few of you guys out there have done this, and I'm open to suggestions/questions and appreciate the help!!

 

Well, I recieved the 10 degree locks and I tried them out. They worked perfectly!! Now the valve tip is where it's supposed to be and the height of the springs seem right on!

I also have the new roller cam installed. I used "checking springs" on #2 cylinder and dropped in a couple of used pushrods and roller lifters that I bought to get an idea if the valve train geometry looked OK. Well, it looks way off to me.

I thought (silly me) that the pushrod length would be right since these used pushrods I have are from a retro roller motor. Apparentley, the motor they were in before didn't have a cam cut on a small base circle, because they seem too short....

When the cam lobes are on base circle, there's a pretty big angle between the rocker arm tip and pushrod. The roller on the rocker tip is very near the intake side of the valve stem tip. I see I'm gonna have to do some research on getting this adjusted right. Boy, I hope this swap is worth it in the end..

There's also another issue with what type of oil pan gasket I should be using. The last ime I bought a gasket with the "thick" front seal. I used to think all 400's took this type of gasket. But I've since found out it depends on what pan I'm using. I run a GMPP pan, and it's the same part# as a '69 302 Camaro with a windage tray. So do I use a "thick" front seal or not??

 

Wow what a difference! I just grabbed one of my pushrods from the flat tappet setup and tried it. I could be wrong, but I think that's even worse! Here's 2 pics of non-roller pushrods vs. roller cam pushrods. Both valves are on base circle of the cam lobe. The blurry one is flat tappet pushrod.

But after looking at the pic with the retro roller pushrod installed (the non blurry pic) , I might be right on with the geometry and don't know it. It doesn't look so far off today.

Oh, and here's a pic of the roller vs. the flat tappet cams I removed.

 

Ok, so I have a question for the knowledgible on this....I know it's not a perfect pic, but how does the geometry look to you guys?? -I think it's pretty good, because on base circle of the cam, it's starting out on the intake side of the valve stem tip, then at mid-lift it's pretty much near the center of the stem tip, and at full lift it ends up just slightly towards the exhaust side of the stem tip. -But how far towards the exhaust side of the valve stem tip should it be at full lift??

 

Don't worry about "where" on the valve tip the rocker lands. The absolute location is not what you're looking for.

Instead, concentrate on getting the pattern AS NARROW AS POSSIBLE. That indicates that the rocker is pushing as straight down as possible on the valve tip throughout its arc, and sliding across the valve tip as little as possible. This push rod geometry corresponds to max lift (min lost motion) and min guide wear.

It can never be perfect of course, since the rocker tip swings in an arc, but the valve tip moves in a straight line. Also, you may find that "optimim" geometry occurs at some push rod length that you can't actually buy; in fact it's almost certain that it will. If that happens, use the next shorter push rod selection that IS available; that will bias the "error" in the direction such that the side loading on the guide occurs when the valve is near the sea, and the sprign load (and therefore the force on all of the parts in any direction) is at its lowest.

 

Regarding the excess oil on the spark plugs, did you use thread sealant on the rocker studs? Dart 200cc ported intakes probably have the rocker stud mount open to the top of the ports.

Without sealant a lot of oil will go down past the threads.

RBob.

 

Sofa – I read your response yesterday, (several times!) and since then I’ve been doing further searches on how to determine correct pushrod length. From what I see, there must be several different methods. I’ve seen others say that you want to have a narrow pattern, others say it doesn’t matter it just needs to be centered on the stem, others have a “½ lift method”, while still others mention a “1/3rd lift method”. All this just makes it more confusing to me. It doesn’t appear to be anything that’s precise or really measurable. None of the methods described seem to involve a measurement of any kind. So – since your procedure IMO is the most straightforward (and I’m convinced you know what you’re talking about) lol, that’s the one I’ll use.

I also played around a little with the checking pushrod I have, and it appears that if I set it around .050 longer than 7.3, the pattern moves a tad more towards center, and the contact patch seems to get slightly more narrow. I assume I should lengthen the pushrod further until I get as narrow of a patch as possible then? Also, when I had the heads off on a prior teardown, I noticed oil sitting on the back side of almost every intake valve, and had 2 broken pushrod tips again also. --I wonder if valvetrain geometry was off enough even before this cam swap to cause the valve stem to be side-loaded causing oil to leak past the guides…and also the cause for breaking pushrod tips? Does that theory sound feasible?? Or am I way off base here? BTW…the machine shop checked out all the seals and guides and they said they’re good. I run Teflon seals, because I hate the umbrella rubber things.

RBob – You’re absolutely right! The stud holes on the intake AND exhaust penetrate into the ports. I made sure last time to use Locktite thread sealer on all of them.

 

More often than not, with a "big" cam, you'll need push rods that are longer than stock; because to make a cam "bigger", they actually make the back side of the lobe, "smaller". Lift is THE DIFFERENCE BETWEEN the back of the lobe and the tip, and the tip is always made just about as tall as it can be but still be able to slide into the cam bearing. So as the cam gets "bigger", the lifter sinks farther and farther down into its bore when the valve is on its seat, and the rocker tilts farther and farther back, and the geometry gets worse and worse. A longer push rod cures this.

The "narrowest mark" method will give you results similar to the "½ lift" method. Won't necessarily be the same, since the valve stem isn't parallel to the push rod; but it's usually close. If you use the method and adjustment I described, you'll usually end up somewhere in between the "1/3 lift" and "½ lift" points. All of those methods are better than nothing, regardless of which is "best".

You're right, "extreme" precision isn't required; this is almost one of those "measure with micrometer, mark with spray paint, cut with dynamite" situations. You mostly just want to get it close enough to get out of gross error conditions.

Again, it doesn't matter WHERE on the tip the mark is, as long as it's not falling off the edge; very very little side loading results from off-center. Sliding action is the main malfunction you want to prevent, not off-center.

Wasted push rod tips is almost always a result of the push rod hitting the hole in the head at either zero lift or max lift. That will force the push rod off to the side, out of the cup; and/or bend it. If your smoked push rods have a telltale mark on them where they went through the head, then that's what killed them. In that case, open the holes up, TOWARD the stud; or just look at the hole itself with a magnifying glass, and find the telltale on that surface, and grind it out in that direction.

 

First off, thanks for all your help so far Sofa!

I read your post, got some "Prussian blue", and did further checks with my adjustable pushrod. Man, the prussian blue worked better than anything else I've tried..I could see the exact pattern!! Here's what I have found out:

1. When adjusted to 7.2" length, I have a slightly smaller pattern as compared from the 7.0ish used pushrods. The pattern is completly centered on the valve tip (if that makes sense)...and 2:

2. When adjusted to 7.3", I have a VERY noticabley narrower pattern but it's slightly toward the exhaust side of the stem overall. If I take what you've been saying:
Then I think the 7.3's are the way to go. And oddly enough, here's what Jeg's says about 7.3" pushrods:
That sounds like me!

 

Are you using a solid lifter to check?

 

No- I'm using the light "checking springs" and an adjustable pushrod. I know a soilid lifter would be optimal, but I'm pretty confident that the lifter plunger isn't moving due to the spring being so light.

Besides, I don't know if any solid lifter that anyone sells that would be the exact same dimensions as a retro roller lifter...

 

Is there any visible sign of rubbing on the damaged push rods? Either on the head hole, or excessive looking wear where they passed through the guide plates?

You have 1.6 rockers IIRC.... think about the concept of "ratio" for a minute. The stock ratio is 1.5 nominal. Yours are a higher ratio. That "ratio" is the distance from the fulcrum to the valve tip, divided by the distance from the fulcrum to the push rod tip. There's only 2 ways to increase the ratio: either increase the distance from the fulcrum to the valve tip, or decrease the distance from the fulcrum to the push rod; or a combo of the 2.

Which at the end of the day means to the builder, that the end of the rocker that touches the valve is almost certain to be farther toward the exhaust than stock, and/or the push rod is certain to be closer to the stud.

So having the mark out on the far side of the valve is expected; and push rod interference with the hole in the head or with the end of the slot in the guide plate is also expected.

I'd suggest using the better push rods part # 7949, after checking as carefully as possible for any sign of interference between the push rod and the head, or the push rod and the end of the slot in the guide plates. I've had to lengthen quite a few guide plate slots over the years. A 5/16" chain saw file works great. Might not be a bad idea to just go ahead and do that to ALL of them, just to be on the safe side.

 

Sofa – I have 1.5 ratio rockers. –And thanks for the explanation on ratios, it helps!

I’ll have to get a pic up of a couple of the old pushrods when I get home. I do recall that you can see a little discoloration where the pushrods pass through the guide plates (from rubbing), but I’d assumed that that was normal wear since they are not self-aligning…it’s certainly not “wearing into” the pushrods by any means, nor does it SEEM excessive (to me). So far as any pushrods hitting the holes in the heads – well, I think the guide plates would touch the pushrods before they would rub on the holes. I really haven’t checked for bent pushrods….guess I’ll roll them on a piece of glass and find out.

But – I DO plan on taking your advice and looking real close at this pushrod tip problem. And I’ll go ahead and lengthen the guide plate slots just to be safe. I can’t hack out too much though – can I?? Thanks for suggesting a chain saw file to do this. It would have been my next question!! lol

Oh – And I do plan on buying a decent set of pushrods……I just threw that particular one on the post because it says that 7.3” push rods are for a retro roller conversion. –Of course I discovered that after doing all this measuring….but it needed to be checked regardless anyways.

I’ll post up what I find….

 

I took a pic of my pushrods and the valve tip after I blued it with the PR checker set at 7.3". I found no bent pushrods and the tips were broken pretty cleanly off, like the last ones. I also don't see anywhere they could be contacting the head holes. They're pretty big on the Dart heads, def. bigger than stock heads...

I looked at all the guide plates too, and they still look new. I'm gonna file them down a bit anyway, because the pushrod does come seriously close though. Sorry the pics are kinda blurry, I have no pic taking skills! lol

 

Well, I've gotten a bit done lately and have had a TON of frustration.

I found out that the Cloyes timing chain cover I got wouldn't fit flush with the block. Turned out the part of the casting on the front seal area was too thick and rested against the front main cap. Had to do some grinding, but it fits nice now.

Replaced the rear main seal, discovered I had the wrong one in it before - but that's another issue...went to install my oil pan - I used one of the new molded one piece rubber oil pan seal made for stroker motors by Felpro......I wanted to use RTV sooo bad, but I resisted and used none like that instructions said. This sucker had better not leak..I'm skeptical - do these actually work?

So I get the oil pan bolted over the windage tray and everything looks sweet. I go to turn it over by hand and heard a "clunk" and it wouldn't turn any more!

I remove the oil pan and the engine turns no problem. I then discover the rear crank counterweight that's in line with the oil filter is at it's closest to the oil pan gasket rail is also scraping the inside top of my oil pan. The block and rail was ground in that area by the machine shop for crank clearance.

It's happened before on another pan I had on it, and I ended up taking a socket and putting a slight dent in it so it would BARELY miss....well I did that again, put the pan back on and it's better - but it still barely scrapes when I turn it by hand. I can barely get a bolt in the oil pan in that area now, if I dent it more I'm screwed......I'm thinking about just letting it break itself in. Like I said, it's barely touching, and you feel just a slight resistance when it passes by while turning it by hand. Think I'll be OK?

 

Just take the hammer to the pan.

 

Dent it however much you need; then use a socket-head screw or similar hardware with a smaller OD head.

It won't really "break itself in"; rather, you'll just have this weird noise all the time in your motor, that will come and go with temperature and whatever. I wouldn't build one like that.

 

Well as I said above, I DID take a hammer to it....and yeah, a normal bolt won't fit it now, so I resorted to using an allen head screw.

I'm afraid that if I dent it further, even the allen head won't fit anymore...and there may be an issue with it not sealing in that area...grrrrrr....

But - I guess I'll remove it ONE MORE TIME and try it again then, because I def. don't want probs like that once I get it back in the car!!

I'll have to take a pic of where it's rubbing when I have it apart because I don't think I descibed where it's hitting accurately enough. - I even contemplated grinding a little on the counterweight, but I don't want to screw up the balance any.

BTW Sofa - I rechecked my pushrod-to-guide plate clearance, and they don't come close to touching since I've gotten these 7.3" pushrods, so I see no real reason to increase the slot length. So I'm putting them back on as is. I think the valvetrain geometry was screwed up when I had the flat tappet cam in, and caused the pushrod tips to break. I don't think I'll break any more now...I hope.

 

OK, I removed the pan, took a couple of pics to show what I'm talking about.

I then commenced project "make it fit", and all is well now! The oil pan is all tightened down and no rubbing!! Of course, I don't know what it's gonna do once the engine warms up...

Now to break out the thread sealer, and get the rocker studs installed. The end is near!

 

Holy Oil Leak From The Future, Batman!!!

That place where the crank has been rubbing, looks to me like it's more than halfway through the pan metal. I'd strongly recommend doing something to seal it up; which you're kind of stuck with doing from the outside. At least glob some epoxy over that spot, so in case the metal fatigues and cracks right there, it's at least somewhat stopped up. Wire brush and lacquer thinner it real good so the epoxy has the best possible chance. No sense having a nasty and much more difficult to fix problem on your hands a couple thousand miles down the road.

What I usually do in situations like that, is IF POSSIBLE, bolt the tin on by a few of the bolts near the offending spot; and stick a long punch through and punch the metal out as far as it needs to go. Another thing that often helps is to bend the entire pan outwards along there a little bit, so that it forces itself outward agains the bolts.

But if you've got it to where it fits and clears, just leave it alone, and spooge it over, and it will most likely be fine. The spooge probably won't even be necessary; but if your luck is like mine, then the very act of doing it, will prevent the situation that requires it; and the act of NOT doing it, will guarantee that it becomes necessary. The story of my life in a nutshell, right there.

 

They say a pic is worth a thousand words....lol

Now you can see why I'm frustrated every time I put a pan on this thing! Yeah, I thought of the epoxy thing on my last pan - it was even worse!! But it didn't leak. This one is actually in better shape. I'll "smunt it" anyway just in case, but if it was gonna crack in that area - it woulda done it when I was whacking on it with a hammer, but it's still intact! And it's not rubbing.

Oh, and Sofa........my luck is way worse than yours!

With my luck, a rod will cause a leak in the pan before that scrape will!!

 

Everything's going together fine now. Of course, I've done this a few times...

I'll get a couple more pics, and post up what I used along with all the part #'s I can scrape up. It may come in useful for someone...

But I do have a couple of Q's. I've used these Felpro print-o-seal intake gaskets before, but I've always used RTV around the coolant and intake ports contrary to the instructions and due to my own mistrust. Will they really seal if installed w/o RTV?

Same question regarding the oil pan gasket. It's a one piece molded silicone type also Felpro. I already installed it dry according to instructions and I'm not getting a great feeling. But it SEEMS to fit well w/o RTV... I guess I'm old school and don't have a whole lotta trust for these "no chemicals needed" gaskets!

 

I've used the one piece gaskets twice now....both leaked in the front with no sealer. I had to drop the front of the pan and put some sealer on the timing chain cover and front of the oil pan for them to be leak free. I've heard of some people using them with no sealer but it didn't work for me.

 

Thanks jbenge, that's what I need to know! Especially good to know BEFORE I drop this engine back in the car. With a windage tray, dropping the pan while the engine's in is not an option.

Anyone else had any luck with these?

 

hey confuzed those part numbers would be greatly appreciated, i have the same exact setup you do if you remember me.. Im going to be chaning over to roller this winter. Keep me posted on how its coming along... Whats up with the rocker studs? i have the dart 200cc heads also and all my plugs look just like yours one or two come out looking clean but for the most part they are oil soaked. And to top it all off ive had that same problem with the pushrods in my 406(been re-done and out about 6 times also) here is my rocker and pushrod pic.. mine was from the junk proform rocker arms. changed over to the comp magnum and have had no trouble since, we'll see what mine look like when i come apart this winter. Did you have any noise with the broken tips? or damage your rockers?

 

[QUOTE=camarokev400]hey confuzed those part numbers would be greatly appreciated, i have the same exact setup you do if you remember me.. /QUOTE]

Sure, I remember ya! And yeah, I'll share the part numbers. Looks like you're also familiar with the broken pushrod tip syndrome!! Frustrating isn't it? I was running Comp Magnums also...those are the ones I posted above with the chewed off tips in the pics...I wish ya luck when you take yours apart....

Didn't seem to matter what quality the pushrods were. Both sets had the .080 wall thickness. Now I'm using the Comp "High Tec" pushrods, but at least now I'm confident that they are the right length. I'll know in a week or so since I just dropped the engine back in the car yesterday!

A few tips:
1. -DON'T buy any pushrods until you know what length you'll need. And no, calling Comp techline won't help...they won't commit to anything and they'll tell you that YOU need to check it because there really is ALOT of variables such as head milling, decking, head gasket thickness, type of heads etc...that will deviate from a standard length pushrod. Most custom lengths don't cost any more than standard length PR's....Instead, buy a "checking pushrod" and "checking springs" and some bluing.

2. I recommend you stay with ONE cam supplier - don't mix and match parts and brands unless you really know what you're doing. The ONLY things I used that weren't Comp was the lifters...I used Lunati, but I checked with Comp to make sure that they would be OK with thier stuff, and they said it was no problem. Don't be afraid to call the techlines and get cam recommendations etc...and call more than one place.

3. When you buy retainers, get the proper locks too!! -Learned that one the hard way!

Anyways, here's the parts I used to convert to retro-roller:
-Comp Retro-roller cam, HR/SR288 custom ground on a small base circle (for clearance) #12-000-8
-Comp valve springs #986-16
-Comp retainers #740-16
-Comp 10 degree "super locks" #611-16
-Comp fuel pump push rod #4607
-Comp "checking pushrod" #7702-1
-Comp "checking springs" #4758-2
-Comp pushrods #7949-16
-Cloyes "Quick button" timing chain cover #220-9-221 (Not recommended unless you don't mind doing a little grinding)
-Manley spring compressor #41830 (I used air to change springs)
-New ARP rocker studs

I'm still running my roller tip Comp steel rockers, and reusing my almost new timing chain and gears.

Just remember your setup may differ so the list above isn't all inclusive. That's all I can think of for now. Any Q's, feel free to ask!

 

hey thanks for the numbers. A couple questions for you though

1. Whats up with the rocker stud deal? think i should replace mine also, my plugs look like yours by the sounds of it. my heads arent ported, thats the only difference between mine and yours.

2. I was on ebay looking at retrofit lifters and they had a set of comp cam lifters on there and they said made for small base circle cams? you know anything about that? the number was cca 891-16.

3. how about a solid roller cam, the lifters seem to be a whole lot cheaper, you think about going that route and if so why didnt you?

 

1. If you have the same heads, then your studs also go directly into the intake port. Somebody posted a pic of those heads, with a flashlight shining through the stud hole into the port. That's common on aftermarket heads. Stock heads usually have a water jacket right there, but to raise the port roof (which is what you have to do to improve flow), most racing heads do away with that part of the water jacket. Which incidentally, means that if you use screw-in studs in STOCK heads, and you don't put sealer on the threads, you end up with anti-freeze in your oil. Very very bad.

2. With a small base circle cam, the lifter goes down into the lifter bore farther when at zero lift; and it can go so deep that the oil band around the lifter completely goes below the oil passage around the lifter, cutting it off. If that happens, no oil (or very little) will get to all the lifters in front of that one. Again, very very bad.

3. I think about that every once in a while myself.....

 

I use Locktite thread sealer on all the rocker studs on the end that screws into the head. Oil used to wick down the threads and pool oil on top of the intake valve (via the "hole" in the intake port). So when I started the car first thing in the morning, it would smoke.

Sofa - So you mean to tell me since I had my cam cut on a small base circle, I'll have no oil to my lifters? I thought the main reason for "small base circle" cams, is for clearance issues (i.e. rod to cam lobe, counterweight etc..?? Never heard of the lifter thing.

Solid lifters are great if you don't mind an occasional valve lash adjustment, and you'll rev higher. It also allows you to run a more radical duration/lift cam for more power up high. And no valve float!

I prefer to have my redline around 5500, with plenty of TQ and HP peaking around 5K. I think a hyd setup is more reliable for a car like mine, which is 95% street driven and maybe taken to the track on test-n-tune days just to see what it'll do...

 

Right... that's exactly what they're for.

Problem is, it's possible for the lifter to sink SO FAR down into its bore when it's at zero lift, that the oil band around it no longer lines up with the rear-to-front passage drilled through the block. Remember that the lifter bore is perfectly round, and the lifter fits tight to it, and that the oil band around the lifter completes the passage. If the oil band falls completely below the passage, then no oil can flow around the lifter; and no lifters in front of that one, will get oil. So the "special" lifters There's ALOT of tolerance in where that passage ends up: in fact, if you look at your own block sometime with the plugs out of it, you'll se clearly that they drilled half of it from the front and half from the rear; and sometimes those miss so bad, that half OR MORE of that passage is blocked.

Incidentally, that also applies to the passage ABOVE the lifters, that feeds the bearings. That's one of the standard prep steps for maxing out a stock block, to gun-drill those passages for unrestricted flow.

Here's a pic of how much the oil band gets moved. The lifter on the left is a Comp 891; the one on the right is an Isky Red Zone. Look how much higher on the lifter the band on the 891 is.

 

Here's all I know about it:

I don't have a "late-model hydraulic-roller block", so it doesn't apply to my 400 I would think...no roller anything back then.

 

That's a whole different issue; has to do with the top of the lifter falling out of the "dogbone" thing in the late-model factory roller system.

Those 2 lifters in my pic are both solid roller lifters, of the original design. Both of them use vertical link bars.

The issue I'm referring to, applies to ALL blocks; early, late, 400, 283, Vortec, whatever. It also applies to all other motors that use a similar lifter oiling system (AFAIK all American V8s, among others).

 

So I'll ask the question again - I understand what you're saying about the lifter falling lower in the bore when using a cam cut on a small base circle. It makes sense.

-But- I don't think I have any kind of "exotic" setup that neccessarily requires .300 taller lifters. (BTW Lunati doesn't even sell a special lifter for this, and Comp lists them as a "new" item). So I'm pretty sure people have used standard retro roller lifters for quite a few years with small base circle cams and are not having problems. I suppose it could happen if the base circle was cut unusually small.....but I'd like to think the cam companies wouldn't gring them that far - right? And if they did, they should tell you that you'll need "special" lifters.

My engine is together, back in the car and sealed up - not a good time to hear that I'll need taller lifters.....

 

"Taller" is not the issue I'm talking about here.

The location of the oil band, is.

Look at the 2 pictures. It's not totally obvious, since I didn't show the push rod seat; but there's no significant difference in the overall height of those 2 lifters. What's different about them is that the oil band around the 891, is moved up on the lifter body about 1/8" as compared to the Red Zone, so that even when the lifter is all the way down in the bore as low as it might go, the oil band around the lifter still lines up with the passage through the block.

This has nothing to do with "height".

Most likely you won't have a problem. Those lifters are SOLIDS, not HYDRAULICS. They're designed to work with cams giving valve lifts in excess of .700". The 891 is designed for cams with lobes that are shrunk by an additional .075" or more.

Hydraulic rollers don't have enough lift for it to become an issue. Remember, the TIP of the lobes is ALWAYS at the same height, no matter what your cam's lift is (for any given base circle, that is); on a std base circle cam, it's essentially as tall as it can possibly be and still fit through the cam bearings. The way they make a cam "bigger", is by grinding the BACK side of the lobe down SMALLER. So as you make a cam to have more lift, the lifter sinks farther and farther down into its bore at zero lift. Likewise, when you reduce the base circle, the lifter is farther down into the bore at ALL lifts. So where you run into the oiling problem, is with VERY HIGH lifts (far in excess of any hyd roller usually), and VERY SMALL base circles.

FYI, the cam in the picture is a small solid roller, a "street" one really; it's only about .600" or so valve lift. But, it's a stroker setup as well, on a .900" base circle. But still, look how SMALL the back side of its lobes are, even though it's a low lift one in comparison to solid rollers in general; and therefore, how far down into the block that the lifters will descend. I seriously doubt that your cam has such small-diameter lobes on the back side as that one.

Incidentally, the way people dealt with the oil passage alignment problem in the past, was to simply gun-drill the passage through the block, LOWER than stock; and then regular lifters would work fine. If you're going for broke on a block, and gun-drilling the passages anyway, it's just a crank of a handle to move the passage down .100" or .150" or whatever. Free basically.

 

thanks for the info on the heads, i bought them pre-assembled so i dont know if any kind of sealer was used but i will def check that when i do my retro fit.

Didnt mean to scare you about the lifters confuzed, I was just searching for a decent price on roller lifters and came across those and was wondering what the deal was.

But as far as solid roller goes, is that something i would want for the street? 6000 is about max for me

 

Nah, it wasn't you who scared me kev, but Sofa was doing a great job!! He had me second guessing myself, and I know d*mn well I did alot of research and didn't just "jump into it".

So far as whether to go hyd roller or solid, I only have my personal opinion. I figure on going 5500, maybe 6K tops and I think a hyd roller will get me that. BUT - if I were building a car that'll see a decent amount of track time, I'd jump up to the solids, due to the fact that there's just more potential in the upper ranges for 1/4 mile performance. Just my take on it.

 

running yet?