got my block back from the machine shop. 400 20 over w/ dished pistons. im going with vortec heads for the time being. now its time to make horsepower and torque. will somebody please run some cam and carb ideas by me. would like to reach 350 hp and as much torque as possible. torque is what i really want. going in a 84 Z28 thanks 359PETE

 

You should be in the mid to low 220's (@.050") on the intake duration and about 8-10 degrees higher on the exhaust side. If you can keep the lift below 500 you can do it with a single spring (Z28 style). Run a dual plane like an RPM and either run a 750 vacuum if you are mainly cruising or if you are going to be running the daylights out of it, then go with a 650-700 mechanical carb.

Just one engine builder's opinion.

 

thanks machineman, this question i have asked more than once. you are the only person to answer. its very close to the answer i got at the speed shop. what kind of torque might i expect to get out of this set up going w/ a 650 mechanical carb. balllpark figure will do fine. thanks for the help 359 PETE

 

What is your intended use of the engine? Daily driver, street performance, street strip or strip only?
What tranny are you using? if auto what stall are you running?
What is your rear gear ratio?Posi?

G

 

Machineman, Nice website and a heck of a nice looking shop. One question regarding the .500 lift on the vortec heads, I have a set we are playing with now I measure .518 inches of travel before the retainer hits the top of the valve seal Ive read where you need .060 inches of clearance to be safe which puts you at .460 of valve lift. How does the Z28 spring help with this situation with the retainer being the issue do you need to change the retainer also.

 

the plan is street strip. mainly a weekend warrior. after the engine i plan to build or rebuild a tranny to accomedate it. thinking 700R4 . i want to be able to cruise without overheating and not get my doors blown off. a rear gear of 3.73. later if all is well a set of dart heads iron eagle platinum . i am on a buget and can only spend what i can get away with.

 

Trim the top of the guide with a pc sealcutter.
G

 

Sounds like a good plan. think I'd stick with a 750 vac sec carb...
what ignition are you planning to use?
what kind of red line are you looking at on the 400?
G

 

this is my breakdown. my block 400 bored 20 over, decked to 9.0" stock crank chamfered oil holes, pistons are dished (compression unknowned) rods balanced. these are the things im stuck with. if anyone can tell mea good way to build torque with this stuff i am unable to change please let me know. i looking for a stock type head for now not set on vortecs just was told that they flow well. had this cam in mind however im told the lift is to much for vortec heads.224/234 @.050" 465"/488" lift. really want to get it right the first time. a freind at work may have a set of double humps not sure of the #'swould they preform better PleaseHelp ...THANKS359PETE

 

The double humps can be made to be good flowing heads stock vrs stock the vortecs are better not only due to the flow but they have abetter chamber design. Downsides to the stock double humps are some dont have assessory bolt holes but the can be added, they dont have hardened valve seats. Down sides to the vortecs is they need the specific manifold and are lift limited as you mentioned. There are a few things you could do to gain clearance but I wonder if you just pick a cam with a lower lift it would solve you problem and still build the torque you want try filling out cranes form for a cam reccomendation and see what they say.