I got em, but how will that affect installation? I heard that you need to redrill the pushrod holes...or something to that effect. Also, Will that effect my pushrod length?

BTW, should i use teflon tape or liquid teflon when installing them?

Thanks!!
--Dan

 

nope, they won't affect your pushrods. Depending on your heads you may luck out with not having to elongate the holes. 1.6's fit just fine on my 92 LO3. You'd better check your valve spring clearances though- see a post I made earlier today regarding valve springs. You shouldn't have to use any tape or threadlock on them if you're using new locking nuts.

 

I checked your post. My springs are good to .600 lift, and I am running a .510/.507 lift cam. I just got the larger rockers if I decided to go bigger.

Wait? Will the 1.6 roller rockers make the lift larger just by bolting them on?
It doesn't make sense that the lift can go higher than the cam can make it.

--Dan

 

I finally get to educate someone about rocker arm ratio's! I was the stupid guy last week who didn't know how to do it- so here goes-
(cam lift/standard rocker ratio) x desired rocker ratio= total lift

(.510/1.5 = .34) x 1.6 = .544

 

had i known that I would not have gotten the comp XE 284 and just gotten the xe274. I will need a vad reserve can at that duration.

Oh, The heads are the TFS ones in my sig. They were decked from 67 to 62ccs.

I made a post about that earlier too. I just want to be able to get the right pushrods.

THANKS a lot!!
--Dan

 

What kind of rockers did you get? If you think they'll give you too much lift/duration I'll buy them from you if they're decent. You might have enough vaccuum to stop, I don't know with your setup though. When I put in my cam I almost crashed through the garage door first time I tried to stop- after that I have been careful and gotten used to it. I believe those heads call for the slightly longer pushrods, call scummit with the head number and find out. The rocker ratio won't change the required rod length.
BTW- I'm glad the formula helped you. I got $h!t on when I suggested that it be put in the equations section. I still think it's a great idea.

 

When upgrading to higher-ratio rockers on an older engine, get ready to be replacing the valvestem seals shortly.

The valve spends years being actuated the same range of motion, with the seals wiping it clean every time. Then you add bigger rockers, which move the valves further (more lift) and push the uncleaned part of the valvestem with years' worth of baked-on accumulation across the seal surface. Next thing ya know, you're burning oil.

Not worth the tiny bit of HP you'll get from the upgrade IMHO.

 

My valve stem seals sit in a grove on the valve stem just below the locks, thats where I always see them and thats where I always put them. I don't think they move from that position. Every valve stem seal that I have ever seen looks this way. Can you please explain what you mean by the seal wiping the valve clean? Thanks

 

Im guessing he means the umbrella seals. I have the same style of seals that you mentioned (o-ring style) that sit below the retainers, but on my intakes there is an umbrella seal that sits flush with the head, what kevin is saying makes sense.

 

yeah it sounds like he might be talking about umbrella seals, I'm not familiar with using them, only have used what Comp Cams includes in their kit, which are o-rings. My stock heads don't have anything that resembles a seal that sits on the valve guide on either the intake of the exhaust side, I didn't know if he was talking aftermarket heads or not. What holds these down on the guide anyway? I'm guessing a steel spring ring? Maybe I should get a set, sounds like cheap insurance that my heads won't smoke.

 

formularpm, what are your 60ft times? I'm thinking thats keeping you from running better times. With a 95mph trap speed you've got a low 14 sec car, you just need to get it rolling quicker. I'm on the same boat. I got a big cam without doing the torque converter.

 

Yup, I'm talking about umbrellas, but look at the valvestem area below your o-ring.

It's also exposed to oil and deposits, gets plenty hot so they'll bake on, and that dirty area will be dragged into the top area of the valve guide when you increase net lift...right?

 

My 60fts are in the mid to high 2s. I think that traction is the main problem, and I already have Eibach springs, 2in tube custom control arms, and sticky Falkens, and it still spins. Maybe the sidewalls arent flexing enough to allow good traction. (255/40/17) With all the cash I have put into the car, I really wish it would perform better than it does.

 

You might try LCA relocation brackets. I dunno about yours, but the front of my LCA dropped an inch below the rear when I put in the pro-kit, and I don't get very good traction.

 

back to the original topic, make sure that your new rockers are of the same type as you already have SA or nonSA. if you go mixing you'll most likely have to make a change or two. where are you thinking you'd need thread tape or thread sealer? there isn't any thing to seal doing a rocker arm swap. the push rod length should be fine after the swap if it is before the swap.