BBC EDELBROCK HEADS 540 BLOWER MOTOR

[BOSSMAN]

Here is another set I completed recently for a BBC 540 Dual Supercharged Boat Motor. They are the Edelbrock #60559 head that started out as a 315cc runner 2.19/1.880 valves. I upsized the valves to a 2.250/1.900 using Ferrea Comp Plus Intakes and Inconel Exhaust Valves. I had my way with the ports to make them efficient for the combo. When finished they flowed 370cfm @.700 lift 28" using a 4.500 bore and clay (320cc port). I picked up a ton in the mid-range flow numbers and had a custom ground cam done for the motor and together was worth 150hp over the previous combo.
Valve Job pic:

Exhaust Ports:

Chamber Work:

Short Block Pic:

Motor Complete for Dyno:

[fivestarauto]

custom ground cam you say hmm.. now nick i know you are a smart cookie. so you are aware of the flat cam problem with the big block chevs?? so what steps have taken to prevent this i ask??

[BOSSMAN]

custom ground cam you say hmm.. now nick i know you are a smart cookie. so you are aware of the flat cam problem with the big block chevs?? so what steps have taken to prevent this i ask??

Well....this one got a custom solid roller cam. The lifters have a direct lube or high pressure oiling orifice in the body that constantly lube the rollers and lobes. It was interesting to watch while priming the motor with the manifold off to see what it all looked like in action. This motor happened to have a Bowtie block so the lifter bores were pretty true. Alot of mass produced BBC blocks the lifter bores are all over the place so the only way to correct it is to true the lifter bores and put bushings in them (costs $400-$500). Going to a roller cam can always help the situation over a flat tappet cam but if the bores are out of place real bad a roller lifter will fail too.

[fivestarauto]

so heres the story as i heard it from tom c&s.. tom installed a comp custom grind flat tappet cam into a 427. he went through the break in process and a week later it went flat. so he called comp to complain and they asked him if he put in a zinc additive into the oil and he says no and they say sorry no warranty...

watcha know bout that??

[BOSSMAN]

so heres the story as i heard it from tom c&s.. tom installed a comp custom grind flat tappet cam into a 427. he went through the break in process and a week later it went flat. so he called comp to complain and they asked him if he put in a zinc additive into the oil and he says no and they say sorry no warranty...

watcha know bout that??

That blows for Tom. The oil being produced now doesn't have zinc in it anymore so that is why you have to run the additive for break in. Oil manufaturers took it out for emission reasons over the years. GM makes some stuff called EOS which is a factory Zinc Additive (any GM dealer has it). Anymore with a flat tappet cam I would run the additive on top of some Joe Gibbs or Royal Purple Break-In oil. Also running low ratio roller rockers and even taking the inner coil out of the valve spring (depending on how serious of a spring you have) can help make it live during the initial Break-In. All of this costs a little more money and time up front but at least you won't have a flat cam a week later. If all goes well then you just set the springs back up to normal and run the correct ratio roller rocker.

[fivestarauto]

(depending on how serious of a spring you have)

well in this case you bought and installed them i'm just now getting to install the heads on the bbc and was wonderd about the zinc additive tynan put grooves in my lifter bores to help oil the cam. im going to have to look into this additive

[BOSSMAN]

Here is the link for the Break-In oil http://www.jegs.com/i/Royal%20Purple/831/11487-8K/10002/-1?CT=999
and here is the EOS http://www.jegs.com/i/JEGS/555/28060/10002/-1 Your heads were setup at 135# on the seat and 350# open pressure. The springs should be fine as they are setup. If they were in the 500# range I would pull the inner spring out. Just for a reference a Z-28 SBC spring is 120# on the seat and 300# open pressure. Putting the groove in the bore will help keep it all alive. I would highly recommend the Break-In oil and/or the EOS. Give me a call if you need any help!

These lifters are an alternative to grooving lifter bores and are usually what I use. http://www.competitionproducts.com/prodinfo.asp?number=651080DL

[slownova]

some oil still has zinc in it. the old kendal blend which is now brad penn is one of them.... there are a few others.