383 lacks power

[grumpyvette]

so i have a 1972 k5 blazer with 4 speed sm465 and an np 205 transfer case. I've built a 383 with 882 heads with 1.94 intake and 1.5 exhaust. edelbrock performer intake and edelbrock 650 carb. hei distributer with all new plugs and wires everything else is pretty much stock. I've replaced the fuel pump and played with different metering rods and jets. i am not altogether sure what cam I've got in there as i had several lying around with no spec sheets and just picked the one i thought looked the lumpiest. i was expecting almost 400 horse b ut that now seems like a lofty expectation. the problem i am having is it sputters at part throttle so much to the point i can't even wind the damn thing out, resulting in no top end power. my low end 1st gear works good and second is ok third has now power and fourth is basically just there to keep the thing rolling on the highway. I've checked double checked and triple checked the timing and its good, however this seems to me like a timing/ fuel issue. I'm of the mind that my secondary jets are too rich as my carb spits fuel out at part and full throttle but runs alright at idle and low throttle. i was also thinking that my cam just might not be the right cam for the combo i have. having said that i have a pro comp 220 cam i was planning on putting in and making sure my cam:crank timing was legit. any ideas would be so nice

I long ago ceased to be amazed that so many guys assemble parts of UN-known specifications or mis-matched components expecting to get good results.
as always you drop back to the basics,youll need to do a step by step, test, isolate and verify approach here,verify TDC, on your damper and timing tab match reality and verify your ignition advance curve, and verify each components, functioning correctly, before moving to the next, and with-out knowing your differential gearing and tire
diameter,compression, etc. selecting a matching cams just guessing.
it sounds like you have a restrictive exhaust, or a fuel delivery issue from what your describing, testing will tell!
post your compression test results , rear gear ratio and tire diam and I may be able to suggest a semi matching cam.
without knowing what your dealing with theres zero reason to think that pro comp cam will improve things over the current cam.
whats your fuel pressure/
whats your manifold plenum vacuum read at idle?
whats your max spring lift/ spring load rates and spring bind clearance?
whats your oil pressure?
whats your ignition advance curve?
whats your spark plug gap set at?
can you post clear pictures of your spark plugs?
whats your exhaust back pressure?
are your catalytic converters partly plugged?

yeah! theres a million newer guys in this hobby who, can make a choice, they can either ignore the questions older more experienced guys ask,and learn,as they progress OR continue on the current course or you can ask your self if stopping and reading might actually help rather than stumbling around blindly hoping someone will pull a magic answer, that cures all problems out of no-ware, based on no valid info.
sorry...it takes some basic research and a few quick tests to find valid answers... theres dozens of experienced guys willing to help but it takes more detailed facts

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