Im not quite sure that this is the correct place for this but i am here for some help! I built the motor originally over the summer and put it in and nothing worked.. Motor started out as a gm goodwrench crate 350 which had been sitting in the garage for over a decade brand new. I tore down the motor and cleaned everything up and put in a comp cam 268h, vortec heads, edelbrock epms intake, holley carb 600cfm, hei distributor and upgraded to an alternator and a 700r4 trans. When it came time to start it i had nothing, No spit not spudder nothing. Came here and through the advice of you guys I found out that the rocker studs were being pushed out so i had no compression. Tore the motor back down and found the new cam was defective from the factory and the timing pin was in the wrong location. Comp has since sent me a new cam and i decided on a set of aluminum promaxx heads. I know that im going to have to measure pushrod length but i am trying to figure out what rockers to use. This car is a cruiser that will be played with from time to time and will not be a race car. I am looking for rocker arm advice as im new to building cars. Im a motorcycle mechanic by trade but new to building car motors. I am looking to stay most likely at a 1.5 rocker and these heads have guide plates. So my question what is the best bang for the buck and still quality! I know nothing is cheap and still quality for internals but honestly i dont have $300 or $400 to spend on rockers. I have to get head gaskets which im going by superchevys build of the same motor and using the gaskets they recommend and know i have to run a speciffic intake gasket. I have new lifters, intake and rocker covers and if i have to get taller ones i will but these are fairly tall. So guys what are your opinions! Thank you for your time!!!
Talk to Comp Cams, they should be best to help you. They have a stamped steel rocker with a roller tip that is pretty good. Invest in a length-checking push rod. That will get you the correct length of push rod. I wound up with Lunati aluminum roller rockers for my 355, around $265 for the set. Scorpions are comparable in price. Avoid the no-name specials you see on eBay and also carried by Summit, Speedway and so on.
I keep seeing bad things about comp cams rockers breaking so their stamped steel are the only ones ive really been looking at. Trying to convince myself $300 is worth it for a set of Harland Sharps and that roller rockers are worth it for a street motor. A pushrod measuring tool is already in my shopping cart to make sure that is right! Trying to do this right and make it last
I was looking at Elgin rocker arms on eBay and they looked pretty nice. The Comp Cams "stamped steel" ones are actually investment castings. I had a thread going here when I was looking at rockers in 2015, it may be worth a look. http://www.ebay.com/sch/Elgin-Car-and-Truck-Rocker-Arms-and-Parts/33624/bn_563617/i.html The Harland Sharps may be overkill for a milder build, but nice rockers.
Thank you, i will read your thread i appreciate it. I was on speedway motors which was mentioned above and saw their sportsman rockers and am curious about them. What do you mean by investment castings?
We ran Harlan Sharps really hard on our 1/2 mile dirt car and never had a problem that they caused. They will take a beating but need to be set with the right geometry(pushrod length) to stay away from larger spring diameter your new heads may have. We used both 1.5 and 1.65. We went to T&D's to eliminate the guide plates and will never go back. We also used a stud girdle with them.. Good luck.
Investment casting refers to what is an old process of making highly accurate parts from a poured metal. There is little machining done after that. Less stresses too compared to a stamped product. The Speedway rockers you mentioned seemed to get good reviews.
Awesome Thank you! Ive yet to see a bad review on the sportsman rockers but havnt seen much about them either. Thats why I had to ask.
I suspect you can use your original stamped steel rockers, stock length pushrods but need to be hardened for the guideplates. If you have your heart set of roller rockers I sell a very nice set, I believe they are made by Scorpion but without their name and price tag on them, PM me for prices if you are interested. PRW also make a very very nice economical roller tip, I think they are investment castings. I'm told the term 'investment' refers to the mold is used only one time so they have an 'investment' in the castings.
1000.00 thousand dollar rockers 300.00 three hundred rockers BEGS the Question... for an engine that won't see 6,000 RPM's twice a year (cam specs are at 1500-5500) won't STOCK rockers on a hyd cam be GOOD enough...? i am REALLY trying to be HELPFUL and not a smart@$$
Im leaning towards the cast stock style with a roller tip. Full rollers dont seem to make sense to me. The head manufacturer states they will need longer than stock push rods and from ppls reviews they state its not much longer but are required. Thank you if i decide to go full roller i will contact you.
The stock rockers i have are self alligning and thats why im trying to figure out what to run. Everything i have read says self alligning and guide plates cant be used together
Ps Ps im a smartass and didnt think you were being one. Just trying to find the right parts and many ppl on here have more experience than i do
http://www.competitionproducts.com/ go in here and look around for rockers it's a real good place that sells to the public... these are the verry least you could use---> http://www.competitionproducts.com/...8-150-Ratio/productinfo/RK-840N/#.WH6lrtQrKt8
Since im learning and you seem to know your stuff... Is the long slot rockers listed on there the type i would need since these heads have screw in studs? Also do you have any experience with the sportsman roller tip that speedway sells?
If you're going to go roller rockers, tips or full don't get cheap ones. The last thing you want is one of them breaking and sending the little rollers thru the engine. From what's stated here you don't need roller rockers. Drop the plates, run the self aligning and read up on rocker geometry
Not arguing trying to learn here but if you remove the guide plates dont you wind up lowering the stud and not having much stud to grab a hold of and it changes geometry? Like i said not trying to argue trying to learn. Also do you have anything you consider a good read about rocker geometry?
No need for long slots, those are needed when you run a higher lift cam. I don't recall the limit your lift would have to exceed but you will be fine with the 268 cam with a lift of .456
The guide plates aren't that thick, but if they are thick enough or the studs that short to cause an issue get some "arp" washers to put under the stud to take the thickness up. Usually the studs are plenty long and the holes plenty deep. There's gobs out there on rocker geometry, Google will find it but it's all in the push rod length. Since you're using mostly off the shelf parts I'd bet you a bunch your cam suppliers and head suppliers know what you need. Still a good thing to know about at least the basics so you can talk to them with understanding.
Roller tipped, ball type rockers are a gimmick designed to get your money. There is no advantage to the roller tip. Spintron videos show the roller tip slides and skips across the valve tip. It doesn't roll. The advantage comes when you replace the ball with a bearing. Either spend the money for full roller rockers or go with the stock arms.
Thank you i appreciate it. I just know some people consider some readings better than others and thats why i asked. Im used to wrenching motorcycles which is what i went to school for. So this is a fun learning experience to me. Alot of reading ive found is performance and racing oriented. I am looking for a good performing motor but also dependable.
How much of a difference does a 1.6 rocker truly make and will it cause clearance issues with the valve to piston. The stock pistons are a 4 valve relief piston.
If I have this right you have a crate 350, Vortec heads, 268H cam and guided rockers. It was mentioned that you had screw in studs and guide plates so you either need to go to standard (early style) Chevy rockers or take off the guide plates as already suggested. You cannot run both guided rockers and the plates too. I didn't see it mentioned which push rods you had in the engine when you were having trouble pulling the studs out. Flat tappet, whether solid or hydraulic you should have the long, early style pushrods, while the roller cam from GM needs the shorter 7.200 pushrods. Sorry, I have to go, will finish this a bit later.
Originally i had vortecs and had the longer push rods which we verified they were correct on a previous post when we figured out that i was pushing the rocker studs out. Found out that from the factory the timing pin on the cam was incorrectly placed and causing the valves to come in contact with the pistons. I ordered a set of promaxx aluminum heads and thats what i will be running now. Thank you
I have a set of Harland Sharps in my small block Ford...Over 40K miles and they look and feel like new..FYI..
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