Cam for torque question

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AJ/FormS said:
Your timeslip says the engine is pretty strong.I'm betting you short-shifted it to trap in third/Drive. Second with 3.23s is about 6450 plus slip, so maybe 6700/6800.Your dyno sheet shows a peak around 5800, but the test was stopped before we see where it crashes. We can see tho that the fall off looks to be real slow and gradual.A third gear trap mightabin 4400 plus slip,say 4600.At this rpm it looks like the engine finishes about 60 horsepower down.But worse is if you outshifted second at 6000 rpm to drop into third at about 4100, Of course now it's a city car :(
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You hit the nail on the head. yup I trapped at about 4300 rpm in 3rd pulling hard. Not 100% sure of the rpm...I was kinda more looking out the corner of my eye at scooby's front bumper on his 350 Luv. Wish I still had the timeslip.
 
okay, with stock rockers how do you find correct geometry. I've done it with stud mounted rollers...90* to the valve stem at 1/2 lift anyway. I pulled the rocker shaft and looked for a wear pattern on the valve stem and couldn't really see anything suspicious but then a stamped and roller rocker wouldn't show the same type of wear pattern. Cant be that accurate at a glance either without some prussian blue...I might do that next weekend...prussian blue. nothing seemed loose, a little side play but not excessive and couldn't really feel any excessive play between the rocker and the shaft. I think at the time of the TBI install I might go with the hughes setup... Hughes Engines
Better control and piece of mind...???
 
You will need to slowly turn the engine over two complete revolutions for every cylinder and see what the lifter preloads are doing on that cylinder.As much clattering as yours is doing,it should soon become apparent.
You should also attempt to push the pushrods into the lifters, to be sure the hydraulics are working.
And of course your lifters are not Rhoads or some anti pump-ups right.
And the oil-gallery plugs are all in.
And the oil is circulating properly as the factory intended.
And that the oilpump is not sucking air.
Lessee, what else.
And that the rocker-shafts are correctly oriented.
And that there is one left and one right arm at every cylinder, and that their orientation is correct.

To me, your video sounds totally like excessive lash. As in no lifter preload. It sounds like the rocker arms are bouncing off the rocker shaft, or off the stems or off the P-rods.Whichever it is the stamped arms tend to amplify the racket. Heck, those arms might even be bouncing off eachother!
And lets not forget adequate spring pressure on the seat.
 
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.020 to .050 preload at the lifter right? So I just eyeball it (Cause my eyeballits aint as good as they use to be) to see how far the plunger is away from the retaining clip or something? Would almost be best to get an adjustable, bring em to zero lash and add maybe .030 or .040 thou and check that number against the existing push rods...But that's why I let Ed set em up at the machine shop. I wasn't there the day he did it and came up with the push rod length so I can't be sure how he did it. I don't want to go back to him without numbers if there is an error. I'm not going to hold him to anything...I just want to know and maybe we both can learn something. I just wonder if there is an issue with valve stem height differences causing different preloads on different lifters. If it is off a bit I guess I could compensate with a thinner head gasket, .051 felpro on there now. Wanted to go thinner anyway to get into about a .035 quench area for better turbulence.
 
Well I am using a half turn from zero lash on some blue aluminum roller tipped rockers I bought straight from Chrysler in 99 or so.This has been working for me. I tried less after break-in but that ended up noisy. So I forget the TPI on those rockers, but I imagine that one-half turn is about .050 inch. Not all lifters will run this way. The wire clip types will on occasion spit out the clips. You need either a specialty lifter to run this close to the top, or at the very least,a lifter with a circlip in there. If the lash goes to zero or less,the circlip can take the abuse.
As to eyeballing it, I don't think you can unless the intake is off, and if its off, you can fabricate a wire gauge. Meh, I'm not big on eyeballing this one.
As to squish, I have been successfully running .034 plus/minus .0015, since 2004,with aluminum heads. This is an .039 FelPro and KB107s @about .005 pop-up.
As to stem heights, IDK. A few thou after a few miles is to be expected.And while it might not be pretty to see them like that, as long as the geometry comes in. I'm not sure I would worry about it;much. I mean give them 50,000 miles, and watch those tips dance.
My Eddies have over 100,000 miles,and remain as OOTB. I think, after the initial 1/4 turn failure, I might have adjusted the preload two more times in that mileage. But to be fair, they need it again.
 
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Well back in 99 I wasn't 100% sure, but since it has gone 100,000plus miles. I have to say;YES.
The original pattern was set up for a lift of .542/.542. I then ran a .522/.538 cam on the same set-up.And since 2004 I have been running a cam with .549/.571; still on the same set-up. So I don't want to encourage sloppiness on your part, but since my heads have gone this far on so much laziness on my part, I'm gonna speculate that the pattern may not be as critical as I once believed.I used a locked up lifter and an adjustable pushrod for checking purposes. I bought the Chrysler cut-to-length kit, where you assemble your own pushrods.Big,hefty,cannons, as I recall,lol
 
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AJ/FormS said:
Well back in 99 I wasn't 100% sure, but since it has gone 100,000plus miles. I ave to say;YES.
The original pattern was set up for a lift of .542/.542. I then ran a .522/.538 cam on the same set-up.And since 2004 I have been running a cam with .549/.571; still on the same set-up. So I don't want to encourage sloppiness on your part, but since my heads have gone this far on so much laziness on my part, I'm gonna speculate that the pattern may not be as critical as I once believed.I used a locked up lifter and an adjustable pushrod for checking purposes. I bought the Chrysler cut your own pushrods.
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Well, since I really couldn't find anything wrong short of possible preload issues I'm just gonna do the eyeball thing next weekend for preload. Probably wont do anything to it unless it's obviously way off. I think loose is better than tight..less chance of burning a valve, neither one is good.
Since I'm gonna do the roller tip rockers where I will need different push rods anyway and a thinner head gasket at the TBI install I'll do the complete setup then.
Until then it'll be T-Port Sync and timing adjustments with the new FBO dist. At least with the FBO I can eliminate the wonkey pertronix mechanical limiters from the equation and timing curve adjustment with the fiTech will be much easier.
 
I think you are confused about something. Those are hydraulic lifters. They are self adjusting. We only set the preload to the minimum, in an effort to prevent piston to valve contact in the event of lifter pump up. There is a lot of available travel in those little cylinders.You cannot set them too tight unless you jam the pushrods all the way to the bottom and beyond. But you can set them too loose, and then they be noisy. Any place in between is fair game.
Actually, when I say they be noisy when too loose, it's not the lifters you are ever gonna hear, but rather the clattering rockers as they get to being slapped by the pushrod and/or the stems and/or the rocker-shaft, as the slack gets taken up by the rising lifters riding the cam lobes. Too loose is BAD!
Wait, they are hydraulics right?
 
Yah, you're right a tight valve is an adjustable tappet kind of thing.
 
AJ/FormS said:
To me, your video sounds totally like excessive lash.
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My Video? Don't have a video. Good idea though. I might do that this afternoon.
When I do post the video I expect some replies like "What tick" Well, it's there admitted it is much less than other youtube vids but it is there and it's not like I have never been called anal about this type of thing either.
 
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AJ/FormS said:
Wait,what? no video? OOps I guess I got my watched threads mixed up in my head again. Maybe I need to cut back a lil on the dosage?
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I'm uploading the video right now to youtube
let's see if it works... Okay fellers...Here it is

 
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Two things.

1). That ain't noisey to me. It's not a stock lobe.

B). Did you VERIFY that the tach is reading correctly? My Autometer (Autogage actually) is 200 RPM too high at idle. Put another way, if the tach says 1100, it's really 900.

I like to verify everything I can. You never know.
 
yellow rose said:
Two things.

Did you VERIFY that the tach is reading correctly? My Autometer (Autogage actually) is 200 RPM too high at idle. Put another way, if the tach says 1100, it's really 900.
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Yah, I do suspect the tach...or the one on my dialback light, one or the other. timing light reads 100 rpm higher than the tach.
No, it's not that loud. there are times after a long drive to or from work...54 miles each way, when it will be a bit louder...fully warmed up I suppose. Today's video was after a run for football beer.
I am running Royal Purple 10W40 synthetic. It was quieter with Castrol GTX 20/50.
It's all gonna get better anyway soon with the hughes roller rockers...for the price, they'd better not be crap...damnit!!!!
 
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There a really nice rocker. But may not solve the noise issue.
 
lomchivok said:
Yah, I do suspect the tach...or the one on my dialback light, one or the other. timing light reads 100 rpm higher than the tach.
No, it's not that loud. there are times after a long drive to or from work...54 miles each way, when it will be a bit louder...fully warmed up I suppose. Today's video was after a run for football beer.
I am running Royal Purple 10W40 synthetic. It was quieter with Castrol GTX 20/50.
It's all gonna get better anyway soon with the hughes roller rockers...for the price, they'd better not be crap...damnit!!!!
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I wasn't going to say anything but I thought about it and this is a wide spread issue so I'm going to speak what I know and let the peanut gallery do its dedicated work.


If I were using hydraulic lifters, I would never ever run an oil lighter than 50. It could be a 15w50, or a 5w50 but always a 50.

In 2003-2004 around there, there was some street car classes that mandated hydraulic roller lifters. We were doing some dyno testing on one of these things, which are a PITA anyways. We did some upgrades and updates and on the dyno we were down 15-20 HP and about 600 RPM lower.

After we spent an hour trying the blatantly obvious, we pulled the notes from the earlier tests.

The only difference was the owner just had to switch out to a 30 grade oil. We put it back to a cheap 50 and got a 30 HO gain and picked up 750 RPM. The lifters HATED thin oil and would go into some sort of hysterisis or something. I cringe when guys have to put a 20 or even a 30 grade oil in an engine with hydraulic lifters. It just causes issues.

New, before all the nattering nabobs come along and they'll me their Honda uses a 20 and hydraulic lifter, it's NOT THE SAME. The ramps on some of these cams are fairly fast, and they take a bunch of spring pressure and a thicker oil.

Lots of guys with valve train issues like the OP could possibly eliminate some of their issues with valve springs and a heavier grade oil. If you have a newer designed lobe, 100 on the seat won't cut it. If it's a HRT, 140 is the low side for spring pressure.
 
This is a first, heavier oil making more power. Must be the build itself.
 
Oh that's why my little 367 goes 93 in the 1/8th!
See I noticed that.
Back in 2003 I was having too much oil pressure issues. It kept blowing the oil filter off the pad and dumping oil onto my headers everytime I spent any significant time over 5000 or so. I was running 15W40. My quick fix was of course thinner oil. Well that solved it,sorta. But it seemed down on power. But the cam promptly lost 2 lobes. It was fall so I shut it down for the winter and pulled the engine.
So I tore it all down, cleaned it up,fixed a couple of things recammed it one size up,changed the springs,modded the filter plate, and zipped her back up. I went back to the former 15W40. No more problems and the one-size bigger cam was making me smile. It seemed a lot stronger than it should have, considering the small change,but I chocked it up to a faulty 7 month old memory. Later in July, I got wind of a club setting up an Eighth, so I gave it a whirl and promptly banged out a 93, Wowsers, I thought. This cam got my attention. So I often wondered about the why of that day. Why the somewhat large powergain from such a small camchange. Now you got me thinking. Maybe that previous cam was suffering from an oil problem in more ways than one. Thing is it happened right around the time they took the ZDDP out of the oils and nobody notified me, so I always blamed it on that. Hmmmmmm Oh well, water under the bridge, I'm happy with 93.
And 7000 as often as possible,heehee :)
 
rumblefish360 said:
This is a first, heavier oil making more power. Must be the build itself.
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Nope. It was controlling the hydraulics in the lifter. The thin oil would allow the internals to go into a form hysterisis or some **** like that.


Since I stopped doing any HFT deals back in 2007 I have heard that there are now lifters with new internals that are much closer in tolerance that makes thin oils less of an oil.

There is more to oils making power than just the grade. Stuff like what I'm talking about can drive you nuts. Unless you don't test. Then you never see it. This only happened because it was a regular customer and the engine was done in the shop from the get go, and we had all the dyno, flow bench, cam numbers and such on file.

Everybody likes to love fast ramps, but they can be a PITA. And the fastest ramp don't always make the most HP. Valve train stability is a big factor in ramp speed. So is geometry. On both sides of the shaft.
 
Interesting observation YR. And surely plausible.

While I love and use synthetic oils for several reasons, I have seen no benefit for hydraulic lifters in general from it. They always seem noisier with synthetics. Makes sense as the actual viscosity tends to be lower except at the highest temps, even for the same weight grade.

Perhaps it has something to do with the check valve closure being slower or less complete. it would be interesting to figure out.

Thanks for sharing the info.
 
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