So all the machine work is done on my 74 z28 4 bolt.. i went .030 over with a set of speed pro flat tops with valve reliefs.. umm i think 10.3:1 comp ratio with 64cc chambers.. i have 72 cc chambers (that i know of i hope lol) so im hopin around 9.5-9.8 round there? but anyway this engine when i bought it had a mild crane cam and has a slight lope in it.. not sure of the grind on it or even what crane cam it was so now i get to my real question..

i have 500 bucks (working overtime works for once

keep this unknown cam and get an elec. water pump and a march serpantines adapter for it... or get a cam that i know the specs for sure.

ive never used an electric water pump nor do i know anyone who has used them do they work well, any noticable power increases ect?

 

well, it surely would be helpful to know what cam you have in there... you sure it has no part number on it?

water pumps are known to increase power but i think it be abit more beneficial to know what cam you have in that motor

 

well. im not sure all i did was pull it and clean everything i didnt really take a close look at the cam so i dunno if there are numbers on it or not.. i guess if all comes to i could mic. the lobes and have one of the techs. get a lift and duration out for me.. but i know just by looking at it its much more radical than the cam i pulled from the blazer motor in my camaro when i swapped it (then again i think truck cams are different in the 70's.. not sure..

the water pump idea was a spurr of teh moment idea because i read about em in a magezine and i dont know if i want to run with this idea or not ...

 

i'd do the cam i didn't and well it's very embarassing trying to brag about your motor and then people say what kinda cam and your like uhh i'm not sure lol i'm replacing mine asap!

 

I'd pass on the electric water pump. Hard to say if the cam is a good idea or not without knowing what it is.

 

yeah if its a good cam then it would suck to spend money on the same thing or something less optimal lol

definately try to spec it out. You could send it off to someone who has a cam doctor. lol it will spec out that cam for you

 

 

I will tell you what buy the cam. Make real good power. then buy my CSI billet waterpump. Only used for one season for $100+shipping. Oh and it is Blue. Hell of a deal! And you have best of both worlds!

 

SpeedPro pistons are "down in the hole" .045" at TDC in a stock block.

Using a .030" over 350, 72cc heads, .039" gasket such as FelPro 1004 or 7733-PT2, 6cc valve reliefs, and that KNOWN .045" of deck clearance:

ACTUAL CR is approximately 8.6:1.

Getting this right, is CRITICAL to picking a cam.

Being as how it's as low as it is, basically a stock smogger 70s motor, I'd suggest staying kind of small on the cam, to keep the cyl pressure at low RPMs up. 2 good choices would be the Comp "Dual Energy" 265 (12-208-2), or the "Xtreme Energy" 256 (12-234-2). Going any bigger will result in a loss of bottom end, and will produce one of those motors that has no "leave".... you'll have a "my stock motor would spin the tires, but this high-perf rebuilt one won't" kind of situation. For all I know, you might already have that.

I don't spec cams for "bragging"; I spec em for WINNING. But the choice is up to you.

The water pump idea is not good, should be scrapped.

What exhaust is on the car? Besides the cam that you already know you need, that's usually the best place to spend "found money", if it isn't already optimized.

 

well heres EXACTLY what is in the engine as of now including all bolt ons and the stuff i have put in (keep in mind class isnt until teusday and ill start putting i together then its all apart as of now)

74 z28 block
30 over speedpros (flap top with valve reliefes as said)
new bearings all around
72cc heads match ported
holly contender intake
670cfm street avenger carb
unkown headers (flow pretty decent)
header back 3 inch to flowmaster super 44
planning on stealing the march underdrive/serpantine pulleys from my camaro
streetfighter th350 with 2200 stall
stock gears for now but have the 3.73 and a spool sitting around waiting
and then that unknown lope cam that is supposedly a crane


i have a 268h comp cam in my camaro and it performs quite well has decent low end and after 3k rpm its retarded power IF i change cams i might go with one of those again if not i have heard many good things about cranes "z-cam"