350 push rods

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09-22-2007, 02:49 PM
Motown

350 push rods

Hi all

I am instaling a set of edelbrock performer cylinder heads on a chevy 350, my question is with using the stamped steel rockers do i need to use push rods that are .100'' longer? Has any body run into this?
09-22-2007, 02:56 PM
nitrowarrior

Do your heads have .100" longer valves? If not, mock up the setup and check your tip location.
09-22-2007, 03:06 PM
Motown

tip of the rockers seem to roll to the edge of the valve stem
09-22-2007, 03:11 PM
nitrowarrior

Alignment problem, not a length problem. Guide plate on the heads?
09-22-2007, 03:46 PM
Motown

yea, iv'e got guid plates, i just found on the edelbrock web site that if using stamped steel rockers,to use +.100'' push rod and if yur using roller tip rockers use stock push rods, but how would the lenth help the alignment?
09-22-2007, 04:47 PM
Motown

i would think .100'' is a big difference in lenth, could there be a lot of damage if i use them and there wrong? it could not push the valve open any more than normal because the adjustment would be less right?
09-22-2007, 06:22 PM
nitrowarrior

Denny is bending over backwards here......the research has been handed to you....it's not our motor...it's yours...have you not dug in and gotten the arrow straight on your compass? As simply as anyone can tell you; do the geometry check and align the pushrod attack on the valve stem. Look, Look, Look, see what is going on we'ed all be to help, just need some solid feedback from your findings. Yeah, by the way "MUCHO" damage if you run it like it is. I't not far from being perfect, just some clean info to help you out.
09-23-2007, 01:48 PM
Racecar100

If the rocker tip on the inner edge of the valve stem you need longer push rods if it on the outter the push rod too long. The best set up is right ing the center when the valve is half way open.
09-23-2007, 02:06 PM
Dave Severson

Best way to know for sure what length pushrod you need is to buy a pushrod length checker, they're cheap and accurate... Takes all the guesswork out of pushrod length selection. All the cam companies offer one for sale.
09-23-2007, 02:28 PM
Dave Severson

Quote:

Originally Posted by DennyW

Yes, if he looks at the picture I posted, the valve is depressed. The point of the picture is to show the rocker centered. As in parallel, to check the rocker contact point. :) If he then uses a dial indicater, he can move the rocker until it is centered, and the indicator will show the amount of movement.

Good system, but i stick with the idiot proof (me!) little checker that Comp sells!!!!!:LOL: :LOL: :LOL: :LOL:
09-23-2007, 02:40 PM
pat mccarthy

if the rockers are hanging off the face of the valve stem you need a adjustable guild plates or alot of them are sloted were the studs go thru move them were the rocker are on the center of the stem and lock them down. as for the push rods .i check them at mid lift so there is no guessing the rocker arm may not be true ratio or small or big base circle cam the deck heads height and the valves height set up with longer stems or bigger roller tips on the rockers will all throw off the true push rod size
09-23-2007, 03:06 PM
Dave Severson

Quote:

Originally Posted by DennyW

Oh, you saying you like to work more ?? :LOL: :LOL: :LOL: :cool:

What could possibly be more simple or accurate then a push rod length checker and the mock up pushrod that comes with it?????? Set the push rod, measure it, order the length you need.....
09-23-2007, 03:09 PM
nitrowarrior

Nw I'm confused, He said it's rolling to the edge. Stamped steel rockers don't roll, they wipe/swipe. Is this thing going off to the side of the valve stem or is what he's looking at actually the tip of the rocker contacting the valve stem during sweep motion?
09-23-2007, 03:12 PM
Dave Severson

Quote:

Originally Posted by DennyW

Exactly, dial indicator, and get the rocker centered. :LOL: :LOL:

IF there's no wear on the rocker, ball, or tip and IF everybody has a dial indicator and stand laying around, and IF your eyeball is dead flat accurate on making sure the rocker is centered.... sounds like a lot of variables to me.....
09-23-2007, 05:05 PM
Dave Severson

Quote:

Originally Posted by DennyW

Wouldn't that IF apply to the adjustable pushrod also ??? :LOL: :LOL:

Nope, just tighten it against the stop, measure it. Lots less variables....
09-23-2007, 05:49 PM
Dave Severson

2 Attachment(s)

I don't think you know what I'm talking about, so here's a couple pics. Nothing could be simpler or easier... You don't use the stock rocker, this slides over the stud and rests on the valve, adjust the pushrod to meet it. Measure the pushrod, order that length.....
09-23-2007, 06:16 PM
Dave Severson

Denny, you're wrong. The one is plastic, the Lunati checker in the other picture is not. I will guarantee you either is far more accurate then eyeballing where the rocker arm is at....
09-23-2007, 06:35 PM
Dave Severson

Fine Denny. You're right. You have to be right. Once you thought you were wrong but you were mistaken!!! I flippin' give up!!!!

I've never built an engine. I've never built a Hot Rod. You are the all time master, I know. Please excuse a mere mortal for questioning you.....

The Lunati checker works excellent....Have you ever tried one??? I guess in your shop, they just aren't used? How do you determine the correct pushrod length on a new engine when you don't have any pushrods, a welding rod and more junk from Harbor Freight???? Tell me again what your current job is that makes you such a flippin' expert on everything????
09-23-2007, 06:36 PM
pat mccarthy

Quote:

Originally Posted by DennyW

Yes, I've seen those. The plastic one is junk for sure. And, you still have to add on measurement to the exiting ones taken, not to count how many times you will be rotating the engine over to get the pushrod set right. How is that better ?

http://www.compcams.com/Technical/FA...inGeometry.asp

Verifying Pushrod Length And Rocker Arm Geometry

They come in two different designs, the more expensive of the two being easier to measure (once you have it adjusted to the proper length for your valve train).

Other companies offer their own versions of pushrod length checking devices, funny little plastic things and such with a sheet of complicated instructions to calculate the length. The main disadvantage with these is that you have to order the pushrods and receive them before you know if your calculations are correct.

You telling me a 18.00 dial indicator with base from Harbor freight is to expensive ?

I use my method, because no matter what the rocker ratio is, I can quickly check it in one revolution of the motor.

Notice you measure at midlift.

good deal denny:) i was thinking i was out side on this one ? this is by far the best way the plastic thing on a stick make a good back scratcher. the other one is fine for the makers rocker arm that one looks like a holley/ lunati/crane rocker same maker .will only work for that maker rocker arm. if you start looking at other makes rocker arms they are all different and so is the size of the roller tips so it can not work. we did a test on all 3 types and the lunati was the best on there rocker arm. the mild lift check out i would say abit better the mild lift checker i have is a Ferry heads sold out of the national drag magazine . some time ago is was having alot of diffrent rockers arms coming in so this works on them all .and if done right the engine will make more power and valve guilds will be happy
09-23-2007, 06:43 PM
Dave Severson

2 Attachment(s)

Here's the setup I use, guess Comp and Lunati have a bit different system. Check the attachment at the bottom. It works great.... I can dig through the computer and post references, too!!!!!!!!
09-23-2007, 06:48 PM
pat mccarthy

that is ok dave. but you must use rocker tester arm. same as the maker of the rocker arms
09-23-2007, 06:50 PM
Dave Severson

Well, I'm still doing it. Still turning cars out of the shop. Still have cars drag racing. I'm not the engine expert, but I don't think you are either. Pat is the expert, he has his own shop and works hard at it every day.....

I don't know it all, but your dial indicator method of checking pushrod length is not as good as the Lunati checker that I have been using for years... Comp's way of checking is also very good, but Pat's is by far the best.

But hey, you just keep digging through the computer and posting stuff. I'll be in the shop....
09-23-2007, 06:52 PM
Dave Severson

Quote:

Originally Posted by DennyW

Yes, that's what Pat was just saying in his post. One doesn't work on them all. There is about 8 different rocker ratios to deal with. Wow, how did I know that ?? :LOL:

Because you're a flippin' genius, I guess..... I mean heck, you're the expert, right???? Building them race engines and hot rods everyday must do it for you!!!!
09-23-2007, 06:54 PM
pat mccarthy

Quote:

Originally Posted by DennyW

Yes, that's what Pat was just saying in his post. One doesn't work on them all. There is about 8 different rocker ratios to deal with. Wow, how did I know that ?? :LOL:

well i hope it did not hurt as much as it did me :3dSMILE: miller mild lift rocker has some good info on this i never have used his rocker arms. but it is a eye opener
09-23-2007, 06:54 PM
Dave Severson

Quote:

Originally Posted by pat mccarthy

that is ok dave. but you must use rocker tester arm. same as the maker of the rocker arms

I've always used Lunati. I assumed most knew that each rocker manufacturer had their own... The one you use sounds very kewl!!!!! Got to get me one of them.... Sounds a bit more accurate then a $15.00 Harbor Freight dial indicator!!!!!!:LOL: :LOL: :LOL: :LOL: :LOL:
09-23-2007, 07:00 PM
pat mccarthy

i can not post on here any more i like both of you guys .i just do not want to be in the middle of this.... good nite
09-23-2007, 07:05 PM
Dave Severson

But of course you do, Denny. You're and expert at it!!!! I guess I've just missed the pics of all your shop builds.... As for it being expensive, I guess I could buy one if I wanted it, money's not really a big issue here.... My engine guy has a whole shopful of equipment, but I still do my own assemblies and maintenance.... I realize that my two 500 rwhp Fords (one for each of the cars I sponsor) can't possibly measure up with what you run, but hey I keep trying!!!!

Don't you ever get tired of being right all the time? Must be a lot of pressure to maintain that accuracy..... Heck, I don't see where you find time to run your own shop anymore!!!!!
09-23-2007, 07:43 PM
Dave Severson

575 Rear wheel horsepower???? Sure would like to see the dyno and build sheet on that one... But heck, mine are just a couple old drag car engines that have been competitive for 3 years now, certainly not built for max hp...just for reliablitiy... Heck, my old sprint car was well over 700 at the flywheel, but that was way back in '78 so it doesn't even count now!!!!

Anyway, you just keep on justifying everything. You can answer this post, then as always, you will get in the last word!!!! I don't really care, I work hard building Hot Rods everyday, and have done so for about 40 years now. I don't apologize to anyone for what I do, nor do I rely on past accomplishments, I just keep on building with no excuses or regrets....