SFX099

I am gonna rebuild my '92 305 (188,000 miles) for some performance. I found a cam I want a Mechanical in Jeg's. .500 lift on the exhaust side, sounds like it can help the 305 out. But what I wanted to know was if I can put Solid lifters with all that computer crap(TBI). Any help is greatly appreciated.

Thanks,
Steve

Odyssey

Solid lifters will most then likely set off the knock sensor. Why would you want a mechanical cam anyway ? You know the hydraulic roller design is probably the best to run on the street.

I have a solid roller in my 400 SBC... and I'm saving up for a hydraulic roller setup.

ede

too many good hydrolic rollers out there to use a solid cam

EvilCartman

iTrader: (1)

Why not a solid roller? hehe j/k I've got a CompCams 294 solid w/lifters that have been collecting dust for a long time starting to save up again for the new engine.

Merlin

You can use solid lifters and a matching cam, but if you are going to keep the ECM you'll need to shunt the detonation sensor with a 3.9k resistor so the ECM does not detect false knock. Of, course, you will have no protection against true detonation, and will have to remove the rocker covers to adjust the lifters once a week, and will have to allow your engine a little longer to warm up every day, and will need to have top-locking rocker adjusting nuts so you don't wear out your rocker studs from the constant adjusting of the cam lock or poly lock nuts, but that's O.K. if you're prepared to do it.

EDIT: Sorry if I can't type (or, "keyboard" as they call it now) when I'm in a hurry.
------------------
Rìce is not fast food, but I still eat it.

dimented24x7

iTrader: (2)

evil cam on a LO3 with tbi = non-exsistant drivability and performance. I sugest you re-evauluate your cam selection. Many of the tbi guys who have roller setups anmd 305's have very good success with the lt1 cam. Go over to the tbi board and those who have done cam swaps can tell you what you need to know and do to get the car to run right and get semi-decent performance from the 305.

John Millican

iTrader: (1)

All that is a big myth.

dimented24x7

iTrader: (2)

oh, btw, if your not doing the rebuild youeself it would be much more profitable to get a crate 350. Even so, rebuilding a 305 usually isnt money well spent. Seeing as how you ahve tbi and ypour just starting your buildup, you have a long road ahead of you. Like i said previously, visit the tbi board and get suggestions as to what to do before you go and buy parts.

SFX099

I'm gonna swap to a carb, so that TBI crap is gone. But I love the sound of solid lifters. Seeing as how they might not be to good with that car, I think i might just stay with the Hydraulic setup.

AJ_92RS

Not really.

I've had a few solid cams and I can say a few of his comments are true.

Using poly locks is the only true way to keep the valve lash as accurate as possible for any extened length of time.

Then, to keep from having to adjust the rockers every week, you should use stud girdles, and those aren't cheap, nor do they easily fit under valve covers. You have to use perimeter style covers/heads and they have to be tall covers.

And it would be absolutely necessary to use bolt in rocker studs. A solid cam will pull the "pull out" studs (as ede calls them ) within 2k miles.

Although saying that you need to let the engine warm up longer is not true. That only applies to forged pistons. Solid cams don't need as much oil as hydraulics because they don't "hold" the oil.

As far as the knock sensor, it's hard to say. Some of the cams I've had were so quiet, nobody believed me that they were solid. That's doesn't remove the fact that the knock sensor won't pick up the noise though. Although I guess that's irrelevant since it sounds like you'll be removing the ECM anyway.

Merlin

Mr. Millican,

I respect your opinion. I was only trying to paint a "worst-case" picture for Steve, since he should expect at least some if not all of those situations with a solid lifter cam.

I understand that a properly adjusted solid lifter valve train makes no more noise than a hydraulic. The trick is in keeping them adjusted. I remember the old Chrysler crooked sixes that would run forever with 40+ thousandths of lash, and no one ever bothered to adjust them. Of course they still ran, just not as well as they were intended.

Perhaps adjusting weekly is a little excessive, but I've known those who have done it after every few runs. And the constant adjustment will either wear the studs with self-locking buts, or will require a jamb-nut setup to prevent the thread wear.

As for the detonation sensor, the 305 used a sensor that is almost three times more sensitive than the 350s used. The extra sensitivity of the 305 sensor might tend to detect other mechanical noises more easily while trying to "listen" to the chambers through the extra cast iron. Also, since the camshaft and valve train have a variable RPM, the frequency of the noise could cross the tuned frequency of the detonation sensor a few times in the anticipated range of RPM (500-4,500 or so).

As for the extended warm-up, most people don't allow their engines to warm adequately in the first place, and with the disparity of the rates of expansion between the steel push rods and iron/aluminum castings, plus the fact that the push rods don't heat as fast, there would be more lash as the engine warms up until the push rods are warmed and everything is at operating temperature. While a hydraulic lifter would compensate, a solid would just allow the extra lash until the push rods grow. The cold, thicker oil would tend to muffle some of this noise, but it would still be happening.

As I said, no argument, but I was only pointing out some of the potential consequences of using a solid lifter cam. Most people have little or no experience with them, since the last engine I am aware of to be delivered from the factory with solids (excpt for diesel injection systems) was the 366T engine in medium duty Chevy/GMC trucks, and they went hydraulic some time in the early '80s. I can't remember the last Chevy passenger car to have solids, but it may have been the '68 302s, and you don't see many of those running to the local Wal Mart on a daily basis. Since Steve may not have known what he was in for, I was trying to encourage him to look at a hydraulic roller setup as an alternative. They are much better than flats, and are probably as good as a solid lifter (flat or roller) up to 6,500 RPM, or in the common street RPM ranmges.

And it isn't B.S. - I DO eat rìce.

John Millican

iTrader: (1)

LOL! You make me laugh.

I was just lazy to type when I added the " " flag.

You did paint a worst case picture. It would probably discourage most people from switching to a solid cam too.

I dodn't personally have one YET but plans this year call for a large solid ROLLER cam. The roller will help with the noise I'm positive.

I was also un-aware about the extra sensitive 305 KS. Thanks for adding that.

With high quality poly locks on the rockers I've seen solid roller cams keep their lash for a year too.

jamesbob02

I can't profess to know a lot about this subject, but if you guys are arguing over using hydraulic roller or solid mechanical lifters, you'll have a harder time using more agressive lobe profiles on the cam because the solid lifters will "dig" into the lobe, which is not good (friction, etc), so they have to have a more of a "ramped-up" lobe profile, which causes for less "area under the curve" so to speak. Obviously, roller lifters don't have this problem. I honestly don't see why you would want to go the solid mechanical route at all but to each his own I guess.

BTW, if I misunderstood and you are simply arguing between solid roller or hydraulic roller, my bad!

RB83L69

I've had probably half a dozen solid cams in my own cars, and I can't tell you how many motors I've built with them. I don't have lash problems. I hate Poly-Locks; usually I just use stock nuts, and add a jam nut. Cheap, easy, permanent, fits under any valve covers, more reliable by far than Poly-Locks.

A properly adjusted solid cam sounds no different from a hydraulic. If you don't know how to adjust one, and leave too much lash on some or all of them, then they can make a ridiculous amount of racket. Personally I can't stand noise from an engine so I adjust them correctly.

This talk of having to adjust them all the time is also typical of improper adjustment. The last solid cam I had in my own car was in the 400 that was in my 83 for a long time. It was a Comp 282S, and was in that engine for about 110,000 miles. It would go about 15-18,000 miles between adjustments. Sometimes after an interval like that I'd go ahead and adjust them just because I could even though they didn't really need it, if I already had some of the parts like A/C or plug wires or whatever already out of the way. And I didn't even have roller rockers, I had Comp 1416 1.6 roller-tip ball-fulcrum ones, so there was seat wear adding to the adjustment need, and it still lasted a year or so between adjustments, and it was not any noisier than most people's hydraulic setups.

daverr

iTrader: (1)

im kinda getting the sense of some of u knocking solid cams.Why would anyone use a solid flat(or hydraulic) cam instead of a hydraulic roller???um cost!!!!!!
for all out race motor solid (flat or roller)is the way to go

i think the real reasoning behind the invention of hydraulic tappet
is to reduce maintence cost ,thus taking the money out of mechanics pockets.

theres nothing wrong with solids.learn to lash its not hard.


dave

jamesbob02

So just get solid roller and deal with having to adjust it more.

82camaro

In a street car, with a 'performance' engine I fail to see the need for a solid lifter cam. Is their that much gain in performance in a typical street warrior engine with solid lifters, compared to hydraulic. Once you get past the limits of the hydraulic lifter, then yes, a solid lifter is the way to go.

John Millican

iTrader: (1)

Once you drive a car with a solid lifter cam you'll understand. It's a big differance.
Just for fun get desktop dyno 2000 and do some bench building and compare solid vs hyd.

82camaro

Actually, I know. Just trying to get the arguement (is the added performance from solid lifter cam worth the added maintenance and other cons?) started. I think that is the question he needs to answer before he choose his cam. The answer is different for everyone though--obvious from the other posts. For some, a solid lifter cam is absolute race only--and for others it's streetable and every engine should have one. IMO, The more of a 'race' engine it is, the more advantage of running solid lifters--too a point where hydaulic lifters are a terrible choice. Posting some desktop dyno results would be nice--he could see an estimated performance difference

SFX099

I have Desktop Dyno. The combo I want to build now is:

344hp@6000rpm-------------335ft lbs@3500 Hydraulic Flat-Tappet
364hp@6500rpm-------------350ft lbs@4500 Solid Flat-tappet
385hp@6500rpm-------------365ft lbs@4500 Roller Solid or Hyd.

In conclusion I believe It might have to be a Roller motor. Do you guys have any downsides to Rollers I should know about?


Thanks for all the help guys

Vader

We seem to have reached the same conclusion that we have more than once in the past. A hydraulic roller is a very good choice for street performance. Unless you run your engine at a contant high RPM or only twice a week at the track, the hydrauic roller can deliver a lot of performance potential and still maintain the reliability you'd expect from a factory engine. Even the oft-mailigned Desktop Dyno seems to have got that one right.

A hydraulic design will have a sharper preload ramp than a mechanical roller, which helps lock the lifter and eliminate pump-up and lost lash at upper RPM. That design feature, in addition to a little judicious preload adjustment on the part of the installed (i.e., no more than ¼ turn after the zero lash point) can make a hydraulic lifter perform quite well in the street RPM ranges.

The only advantage the mechanical will have on the street over the hydraulic is more crisp and compliant valve action at upper RPM ranges, and then only with the correct springs. At the upper RPM ranges, the solids will excel because they can tolerate the spring rates necessary to control the entire valve train at those valve acceleration rates.

The belief that a mechanical roller lifter is lighter isn't always the case. The oil fill often makes them nearly an equal mass to their hydraulic conterparts. And at the upper ranges of RPM requiring mechanical rollers, the lifter mass isn't the only item to calculate when selecting springs. And with a higher RPM engine, push rod oiling isn't normally a concern, since anyone running those RPMs constantly is probably using oil spray cooling manifolds over the springs and/or shaft mounted rockers with their own oil lines.

If you're going all-out, the game is different, but if you intend to use the car as a daily or seasonal driver, a hydraulic roller is tough to beat all around.

daverr

iTrader: (1)

COST!!!!!!!!!!!!!!!!!!

solid flat tappet will out perform a hydraulic flat tappet
solid roller tappet will out perform a hydraulic roller tappet

here`s another thing to think about with hydraulic tappets.hydraulic tappets require oil pressure to take up the lash, which makes the oil pump use up more power to keep with the demand of the hydraulic lifters.

honda uses still uses lash settings today on their cars.my motorcycle that i drive everyday in the summer uses sollid lifters.

statements like solids are not streetable .is total bs

dave

Vader

I'm not sure when exactly it was that Honda became the benchmark for automotive engineering and technology, buuuuttt...

I understand what you are saying. Mitsubishi also uses a lot of solid cam followers (NOT lifters) in their engines. I'm sure there are a lot of others, but those two seem to be the ones in for service most often.

Regardless, the volume of oil required to maintain lash adjustment is ridiculously small. I'm not even sure it can be calculated, since the volume of oil going up the push rod to oil the rocker and valve is far greater than that required to maintain lifter height. That includes the oil flowing through solid lifters for rocker oiling.

Also, the pressure required to overcome the lash is between 7-10 PSIG. If your pump doesn't hold that much pressure, I'd be a lot more concerned over the bearing shells than the valve lash. I doubt that the oil pump load on a hydraulic lifter equipped engine is any greater. Generally, far more oil is dumped through the pressure relif valve than is used to maintain lifter body height, even with a stock oil pump and relief spring.

I don't think I said the solid lifter designs aren't stretable. I did indicate they require more maintenance. If SFX wasn't aware of that, he should be now. That was the entire point.

And for another benchmark, REAL motorcycles use push rods, and have been using hydraulic rollers for some time now.

SFX099

Thanks again guys, I do believe I will go with a Hydraulic Roller. Seeing how much power it makes over solid makes it worth while. IMHO I cant see me adjusting my valve lash etc.. anytime after the motor is put together. For this reason I will get a roller.


Thanks again,
Steve