Will 1.6 rr, most likely comp cams pro magnum, fit under the stock valve covers? Also, anyone who has done this, what gains did you see from going from the stock non roller 1.5 ratio to 1.6 roller rockers?

 

I have crane golds they fit perfect under stock valve covers as far as performance the went on with other mods so I can't say..:hail:

 

Did you have to do anything else to get them to fit or were they a direct swap?

 

I am using aftermarket springs,valves cam you name it they where installed in 99 never had any probs everthing fits just fine :hail:

 

Did you have to cut the drip trays out of the valve covers? How about pushrod clearance with the 1.6?

 

IIRC people said they work w/o problems. If not cutting up the stock valve cover is simple enough.

 

Whose IIRC? I'm not worried about the valve covers, worried about grinding pushrod openings.....

 

you can order a 100 dollar set of 1.6 ratio 3/8 stud rocker arms and put them on stock LO3 cars and make a honest 10-20 horsepower gain

centerbolt rocker arms ARE THE EXACT SAME as the old style heads rocker arms

 

if i remember correctly

 

Correct me if I'm wrong but the rocker arms we'd need have to be self-aligning whereas the old style heads did not use self-aligning rockers.

 

I am running a rather small cam 453 intake 488 exhaust lift, erson spings, locks & retainers no cutting was needed
For the 87 and up roller lifter engine you will need to use the self-aligning rockers

 

lets say i still had the stock cam, stock valve springs, and stock pushrods. Would I be able to use the 1.6 comp cams pro magnum rr still using everything stock? Would I have problems with using the stock pushrods? Thanks.

 

we need experts on this one.. it has been discussed in the past.. but when you match the 1.6 rr with lt1 cam it will not work.. so its one or the other with stock heads... IIRC

been thinking baout doing this until i put my lt1 cam in.. can i do anything to use lt1 cam and 1.6RR help me out experts..
Shawn

 

yes what i was trying to say the jegs and summit books list rocker arms for centerbolt heads you can get self aligning rocker arms for any year small block chevy

 

bigREd, you only have to make sure your clearances are where there supposed to be or you could have coil bind in your valve springs. I don't think you have to be concerned about hitting a piston or anything.

25THRSS, you may have more of a valve spring problem running into valve float if you turn your engine too tight, the push rods will be fine.

Steve

 

What do you mean by turning my engine too tight? I don't plan on going over 5,000 rpm's, definitely not over 5,500. You think I would be fine if i kept her below that?

 

Remember guys, to prevent a binding issue use only one method to align the pushrods. Either Self alighning rockers,Guideplates or narrow pushrod slots in the heads but not a combination of

 

I think 5500rpm would be safe if the springs are new and you have never floated your valves before( valve float weakens your springs and will foat the valves at a lower rpm the next time it happens ). As far a coil bind is concerned you have to know what the min. compressed spring height is and the installed spring height is to find out if the combo of cam lift and rocker ratio will cause the spring to bind ie. cause the coils in the spring to come into contact with each other.

Steve

 

do you think this would be a problem on a 152K mile L03 with stock intake, cam and heads. I am installing a new tranny this summer and a L05 350 next summer but would like alittle more power now. Should i have any problems installing some 1.6 stamped steel Federal Mogul rocker arms.

 

anyone?

 

Yea guys i would like to know the same thing also, except my engine only has 75k on it. Would I gain anything from adding 1.6 rr to a stock cam engine, i do got an intake and headers/full exhaust

 

from reading other posts i hear you can gain between 10-15HP with 1.6 rockers on a stock 305. I would probably recommend a cam swap if you only have 75K miles. The only reason i am doing 1.6 rockers is because i want alittle more performance before i swap in a 350. I just want to make sure im not going to break anything but when i think about it im only adding .023/.026 lift so it should not be a problem even with stock springs and 152K miles.

 

Ya know the more I think about how pew-ney the stock cam is you'ed have to rev it past the red line to get the valves to float. I would'nt worry to much with the stock cam.

Steve

 

i am almost sure that im going to install some Sealed Power Long Slot 1.6 rocker arms over memorial day weekend. I have one more question, could i reuse the ball and nut that are already on there, or should i invest is some new ones. Ill probably only put another 10-12K (152K right now) on the engine before i get a new 350.

 

Go with new stuff, it's cheap insurance.

Steve

 

Was doing a little more researching on this and came across this tool on comp cams' website. It gives some good info too. Could this be done with the heads still on the car though?

http://www.compcams.com/catalog/346.html

 

No!!!!!! Where will all the metal shavings go?

Steve

 

Thats what I figured, but I was just wondering if there was some trick someone knew about so that the metal shavings could be cought or something. Guess not, oh well.

 

Alright now I am really confused big time! Comp Cams says it can't be done, but several people have said they installed 1.6 rr with stock heads and cam. Who is right?????!!!!!!!

 

we shouldnt have any problem with the stock cam, i think it is only a problem with high lift cams.

 

You will need to multiply the lobe lift of your cam by 1.6 to find the actual lift at the valve (roughly .030 more lift than with 1.5 rockers). I have found that .450 lift(yes some will take more) with 1.5 rockers is safe on factory stock sbc heads without any clearance problems.When using 1.6 rockers the pushrod moves closer to the centerline of the head and may require that you enlarge the pushrod hole for clearance.

 

Thats what I'm asking. Will I have to clearance the heads or not? This is on the stock cam, springs, heads, etc.

 

I cannot see any reason why we would have any problems, many other people have done this mod and non of them mentions having to enlarge the pushrod holes. Even NJSPEEDER said that is it a direct swap and didnt mention anything about any problems in his post concerning 1.6 rockers and stock cams.

 

I was just making sure. When I do this I do not want to run into any problems at all and I am just covering all my bases. Thanks For all your help! If anyone has anything to add to this you are more than welcome! Comp Cams kind of confused me by saying that when you switch to 1.6 rockers on stock sbc heads you have to drill for clearance. This made me think that no matter what, you had to do this because of the generalized statement they made. So with the dinky stock L03 cam 1.6 rr will be fine everyone says right? There will be no clearance issuses whatsoever? I sure hope not!

 

Just make sure you get the roller rockers for center bolt valve cover heads. I here some rr are to wide to clear the valve cover bolt post.

Steve

 

Okay.. we have established that a stock top end will take 1.6 rr. My question being... I am going to install a set of 081 casting heads, an LT1 cam ( with a 450/460 lift) is there going to be a problem, I done the math to figure the total lift, however I'm not sure what the max is or where to find it.
Scoty

 

vjo90RS8,

I noticed you said you're going with an LO5 engine next summer. I have a set of those heads I've been toying with for my '83 C10.

I have a .443"/.465" cam with 214*/224* duration @ .050" and 112 LSA. I checked the valve retainer-to-valve seal clearance and it's RIGHT AT .050" (the minimum clearance recommended).

My heads have had a valve job done, so the valves are sunk into the head a little more than stock. That could be what's contributing to the clearance I do have. I dunno for sure.

I would imagine the stock LO3 heads have similar clearance. If the heads haven't been touched (i.e. stock) then there may be a problem. Get a dial indicator and check.

But you still have to watch for coil bind to. I haven't done that yet. Sorry.