SoCal Jet Boats
Tech Talk => Engine Mechanical / Electrical => Topic started by: maddogg20 on January 14, 2009, 05:02:54 PM
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Hey guys, Im running a hydraulic flat tappet cam shaft and the specs are as follows.
(https://www.socaljetboats.com/proxy.php?request=http%3A%2F%2Fi162.photobucket.com%2Falbums%2Ft280%2Fandyjman16%2FImage044.jpg&hash=f0c03b4d8f6608163765d5bd530c21200b81950f)
What rocker ratio do you think I should run? I have stock pistons and stock rod length and i want to make sure that the pistons and valves dont kiss one another lol. Any recommendations on rocker brands or models? Stock ratio is 1.5 right? sorry, lol its been a while. Also, do you think ill be cool with 1 piece 3/8 push rods? or should i do 7/16. By the way its a Big BLock Chevy motor.
Thanks,
Andy
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I do believe stock chevy rocker ratio is 1.7 yours calls for a 1.75
You have stock internals so your not building big HP. 1 piece 3/8 is fine or spend the extra and get the 7/16.
Why does this all seem so familiar to me ??? Have i been here before :sly:
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I know that hand writing. Sherry baby. Good choice with a Clay Smith.
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I do believe stock chevy rocker ratio is 1.7 yours calls for a 1.75
You have stock internals so your not building big HP. 1 piece 3/8 is fine or spend the extra and get the 7/16.
Why does this all seem so familiar to me ??? Have i been here before :sly:
You can build big HP with a stock bottom end, they just don't run long....
Maybe should read; You have a stock bottom end so don't build in too much HP, I would go 7/16" PR's and eliminate something to change later, don't forget the right sized guideplates...
I like the steel roller tips for value and performance, I have a set of Comps, pretty cheap and seem tough.IMO.
GT
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who makes 1.75 rockers? I was on jegs and I didnt see any. All I was able to find was 1.7 and 1.8 any recommendations
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I've been happy with Miller Rockers, and Comp Rollers..... or you could call Paul at High Flow Dynamics.... he's put alot of abuse on alot of different brand of rockers, he could probably help you out
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wheres he out of? because im thinking ill give him a call.
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who makes 1.75 rockers? I was on jegs and I didnt see any. All I was able to find was 1.7 and 1.8 any recommendations
http://www.jegs.com/i/Crower/258/73607-16/10002/-1
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are there any alum 1.75's? or would you recommend steel.
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If a 1.75 ratio rocker arm is going to give you 0.575" lift at the valve, then a 1.70 rocker arm will give you about 0.568" lift....or only a measley .008" less, give or take. In your combo, this won't be seen on the dyno and you certainly won't feel it in the seat of your pants in a jet boat. So look for some dime-a-dozen BBC 1.70 ratio rockers.
If you want to spend the money, the Crane Golds seem to be the industry standard...about $335 from Summit Racing by the time they are in your hands. OR, it just so happens that you can get the Millers in a blowout sale for a mere $175/set from:
www.adperformance.com/
Ask for Brian and tell hime Paul Kane sent you for the Miller 1.7 ratio rockers for $175/set. (The Millers are made of 7075-T7 aircraft aluminum and have chromoly polylocks)
LO
p.s.: Jim, I suggest you jump on that deal too; Jim Miller just claimed my last set of 1.7's that you inquired about and I sure as hell wouldn't sell 'em for that cheap anyway. :o
p.p.s.: maddog20, if you don't understand propelry esablishing rocker arm geometry with a custom valve train, then get the help of somebody that knows what they are doing.
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Those Millers are cheap rockers. If you look around they can be had for around $100-120 bucks. I got suckered into a set for $220 and they were OK at best. Hell I found Miller BBC for $80. Not bad for the $$$ if you buy em right, but don't get suckered
http://www.competitionproducts.com/products.asp?dept=114
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Those Millers are cheap rockers. If you look around they can be had for around $100-120 bucks. I got suckered into a set for $220 and they were OK at best. Hell I found Miller BBC for $80. Not bad for the $$$ if you buy em right, but don't get suckered
http://www.competitionproducts.com/products.asp?dept=114
BUYER BEWARE! The big block rocker arms in the above noted link ARE NOT the same Miller rocker arms being sold by AD Performance, nor are they what we have offered in the past.
The rocker arms being offered for $80/set by Competition Products are from a 1st Generation production run, from way back in 1998, which were manufacdtured at totally different foundry, were recalled/reworked by Miller Engineering, and then sold to ONE SINGLE distributor: Competition Products. Miller Engineering sold the reworked rockers to Competition Products with the understanding that Competition Products would express their reworked status to the customers....which they did not reveal. (They offer them as "Engine Builder" rockers.) Miller Engineering dropped Competition Products as a distributor because, as stated, they were not revealing their rockers reworked history.
AD Performance is offering the top-tier, Second Generation, revised/upgraded stud rocker. High Flow Dynamics & AD Performance wouldn't sell them if they weren't top notch, and if they were the reworked 1st Gen rockers (like those offered by Competition Products) then Miller Engineering wouldn't allow us sell them to you without advising you of their history.
That's the history in a nutshell; ColeT with all due respect please get your facts straight before posting. 8)
LO
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I bought a set from them for $119 and they were the PVC Mid Lift yada yada they had a paper explaining the technology behind Mid Lift design not the basic set that I have seen. So like I said they are ok not great but what do I know i run a Rodeck block