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Roller Valve trains....


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OK, Now lets stir this pot:

Roller valve trains, are they worth their expense? Putting a roller valve train in requires a special grind cam, special lifters, push rods and rockers. Add "Roller" to any of the above components and your valve train cost just jumped $500. Is it worth it? Well what I personaly learned is that my car revs so fast ad I have to shift so quick to keep up with the revs, that it is by far the biggest bang for my buck. We are talking about noticable performance here guys, not just a seat of the pants "FEEL", but the kind you can tell immediately. It is costley, but I won't build another motor without going full roller!

 

Opinions?

Mike

 

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"I will not be a spectator in the sport of life!"

mjk

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Guest Anonymous

Interesting topic Mike, some day I may do a cam chang on my engine and was considering going full roller. My block is allready setup to do this but I was wondering if there is really any noticable differnce using full roller valve train.

So, you really can feel the difference?

Does it feel smoother?

 

 

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Dan, 78 280Z, 383FI, 700R4 allmost ready!

http://members.home.net/dporter1/

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Dan,

It revs so much quicker and smoother that the motor just pulls faster due to the faster rev. It makes power Quicker, which is where you feel it most, and with a Manual shifter, you will be rowing gears a llot faster...

 

Mike

 

------------------

 

"I will not be a spectator in the sport of life!"

mjk

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Guest Anonymous

I have to agree with Mike on this...my setup in my V8 Z is complete roller valve train using the LT4 Hot-cam and have had other cars with roller setups and some with out. Seems the cars with the rollers actually ran more smooth, reved faster, and seemd to get just a tad better fuel milage than I expected.

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Guest Anonymous

Altho I dont have roller valve goodies in my small block,, I did drop the extra cash on my 69 427 vette, and it made a world of difference,, it was already awesom, but after the change to roller, it revs more like a 283 than a big block, and it is a bit quicker on the bottom, Didnt notice much of a change in fuel milege

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okay guys,give me some advice on my setup...I'm also running a full roller engine,my problem has been broken rocker arm studs,I've checked coils for binding,plenty of room there. I do have close to 200 lbs.seared pressure/540-560 open pressures,should thesespring pressures be beaking off the tops of studs under low RPMs? Never broke one w/high revs..always at idle after 3-4 hour of drive time,"driving to the track" I've got 7/16ths studs I plan to replace standards with,My question is,should I be looking at other issues before running big studs?

david

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I had a few problems with my valve geometry

so i bought a tool and got the correct length

pushrods and that solved my problems. You may have to shim the studs up a little so you have enough threads for your lock nuts.

I have a Crower 547/567 lift solid roller

Crower roller lifters and crane gold 1.5/1.65

split ratio roller rockers. I think one thing that we are over looking here is engine temperature. I am using the stock

nissan radiator and have had NO cooling problems... I think 180 is the hottest my engine has gotten sitting at a light.. Roller valve trains are a little bit louder

but the performance increase is well worth

the xtra noise and cost.

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It sounds like there is definitely an issue with your pushrod length. You might want to order a rod checker tool and make sure your pushrods are the right length. I am running a full roller hydraulic set up with 1.5 rockers, a custom 1-off ISKY cam with 535/550 lift.

On a related note: While upgrading to new covers I got a tall cover that was still too short for my rockers and I bent two pushrods due to the rocker hitting the billet covers. That cost me about $230 to get the problem resolved and another $120 for new covers that cleared. Car still beat all heck out of a 92 TT 300ZX the day I drove it to the repair shop for the bent rods... Beat the guy even with two bent pushrods... I love my car...

Mike

 

------------------

 

"I will not be a spectator in the sport of life!"

mjk

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For those who have seen the pics of my cars

engine the valve covers are very tall ball

milled billet made by weisco and they provide plenty of clearance for the tallest of valvetrain components. Plus they come in a plain white box and they only cost 70 something bucks!..My original pushrods were

1/4" too short and the rockers were rubbing on the edge of the spring, Talk about a loud clatter! The pushrod length checker is around 14.00 I suggest buying one if you plan on doing any cam/rocker changes.

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Guest Anonymous

Hey David, your problem is with your rocker arms, because thoses pushrods will bend before thoses rocker arm stud break( do you have screwin stud and guideplates) check the clearance between the rockerarm and the stud it should have the clearance of a paperclip, also check as to where do your rockerarms ride across the tip of your valve stem, also check to make sure that your rockerarm is not hitting your spring retainer, if you are using matched cam(not a small base circle),lifters, pushrods, everythings should be good to go, coil bind could be questionable , unless the springs are starved for oil or you ran the car hot, check thoses springs of thoses springs on the broken studs. jack

quote:

Originally posted by David Spillman:

okay guys,give me some advice on my setup...I'm also running a full roller engine,my problem has been broken rocker arm studs,I've checked coils for binding,plenty of room there. I do have close to 200 lbs.seared pressure/540-560 open pressures,should thesespring pressures be beaking off the tops of studs under low RPMs? Never broke one w/high revs..always at idle after 3-4 hour of drive time,"driving to the track" I've got 7/16ths studs I plan to replace standards with,My question is,should I be looking at other issues before running big studs?

david

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Guest RON JONES

If your geometry checks out ok and your still having problems, STUDGIRDLE!If your running a roller you realy should have one anyway.Studgirdles arn,t that expensive and are worth it.I,m surprised I,m the first one to bring it up this far down in the replys.also cam choice is so very important to get the most out of your combo and what you want to do with it.Myron if you ever intend to go roller,or anybody else,let me know.My best freind builds race motors for a living and has a cam grinder that is awsome.I,ve seen a 2700lb nova with a smallblock go 8.70 with one of this guys cams(thats on gasoline and no NOS).Dosn,t have to be a all out racecam,he grinds all kinds of cams.You personaly talk to this guy and give him all your info about your car,tell him what you want to do and he,ll hook you up.I think its CAMCRAFT CAMS but I can find out for sure.This is a much better way to go than big name cam grinders.ULTRDYNE is another very good cam grinder (that who ground the cam in my motor).If your wondering why I don,t have a CAMCRAFT cam,my buddy hooked up with him after I allready bought my cam(but i,m thinking of changeing it).

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Wow..good advice here.

My setup is a Comp Cam full roller kit from summit. The installed height of springs was just a tad under min.specs from comp. I have 20-30lbs more pressure then called for,rep for Comp Cam assured me that as long as coil clearance "binding" wasn't a issue I could run a little higher press. I have inspected push rods,and none show signs of bending. I've checked clearance of base of rocker arm with springs,retainers,etc. The only thing close to binding is were push rod comes up thru head...no room for larger pushrods,very tight clearance here.But that shouldn't cause a problem? Why would I only have failure of "2" studs both after driving 2-3 hours highway driving,and when decelerating...on two seperate occasions? I will be installing 7/16ths rocker arms & studs soon, if I can't find other reason for breakage.

David

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Back up Ron, My already is a solid roller! I David is the one having the tough time with a couple of studs. I was told that a stud

girdle isnt necessary unless you were planing on turning you motor above 6500rpm.

Is this not true?? I do not know....

Any Engine experts want to jump in here?

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Guest RON JONES

Myron,I didn,t know you had a soild roller. When I asked you about your cam,you didn,t say roller lifters just solid lifters.so I tought you were running a solid flat tappet cam.As far as the stud girdle goes,roller profiles have very agresive ramps (even if lift isn,t real agresive)and open the valve alot faster,that creates more strain on rocker studs.Even if your not running above 6500rpm, its a good insurance policy to run a stud girdle with a solid roller.It makes for a stonger valvetrain.If your gona beat on it make it strong.You can get one for a little over $100 and a real good one for $200.With all the money a roller valvetrain costs,Its worth a little more to make it strong.

 

[This message has been edited by RON JONES (edited February 15, 2000).]

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What I was told was that if you don't plan on reving the motor above 6500rpms, you don't need a stud girdle. Also triple checked that with several other builders, and got the same response.

 

Mike

 

------------------

 

"I will not be a spectator in the sport of life!"

mjk

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Guest RON JONES

Mike,I don,t think dave,s got that much lift.But he,s got the spring presure for it.200lbs on the seat is a good amount.I,d like to also thank you for a civil reply.I didn,t want to start a agument.

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Sheeit,

Guys,I figured eyeballing my new stuff "rockerarm/studs" that this would be a simple unscrew/replace an readjust....what's the talk of head machining here? these are labeled "small block"7/16ths. The girdle wouldn't help my studs breaking off at or above where threads start...right under the lock nut.

David

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Ron,

I am not gonna do on this site what has been done on Zcar.com. This isn't my world, it's ours. We all have opinions and views, and we are not gonna always agree. However, that won't mean I'm always wrong, or always right.

Also, I understood that he was pushing the spring presure, not .700 lift... that would be much to much lift for that motor combo he described.

 

I'm just happy to be here, in a forum where I can feel OK about having the car I have!

 

Mike

 

------------------

 

"I will not be a spectator in the sport of life!"

mjk

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Guest RON JONES

Mike,there is more to just rpm .Even if your under 6500rpm.In daves case he,s got alot of valve spring presure,probly enough for .700 lift.All that valve sping presure is alot of strain on the studs.After reading your reply I made a couple of calls myself.We,re talking solid roller (not hydraulic)with all that spring presure,a stud girdle is a good idea.I,m not trying to start an agument,I just don,t want to misinform any one. lets not forget he,s only got 3/8 studs, and a stud girdle is cheeper than going out and buying new 7/16studs and rocker arms.BTW he wouldn,t have to take the heads off and machine them for the new studs ether.Easyest and cheepest way to fix his problem.

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I hear ya Ron. I missed the fact that his wasn't hydraulic. My bad. If he is pushing over .700 lift on the spring, that is enough to want to upgrade studs and throw on a girdle.

 

Mike

 

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"I will not be a spectator in the sport of life!"

mjk

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