mcbchild

iTrader: (1)

I am having a little difficulty trying to determine what the problem is. On the first 500 miles of break-in, I had power that would spin the hell out of my tires and that would only be at 3/4 throttle. I understand that fact that I changed to MT ET Street tires, but I should be able to spin those up atleast around full throttle. The engine over heated once and I did test my compression 180-190 psi on all cylinders, Changed the hydraulic flat tappet cam springs and lifters, verified valve lash is at 0, timing set at 38 btdc. changed to an aluminum water pump,installed new intake and exhaust gasket, changed plugs, changed to an Pertronix HEI race dizzy, new plug wires, new stall converter and thermostat. It also has no more power after 6200 rpm, just stays flat and will not pull anymore, but the engine doesn't break-up or no type of engine miss.

You guys have any clue that could help me out? I am thinking maybe something wrong with the carb or heads. Checked cam lift and springs again and no problems there.

Thanks for any help.

Supervisor42

This sounds exactly like the engine is leaning out due to lack of fuel.
Check the fuel pressure during an acceleration run. It may have picked up some trash in the fuel system.

mcbchild

iTrader: (1)

I will try that after I have the carb rebuilt and put back on the engine, I was also thinking of changing from a hi volume mechanical carter fump pump to a holley blue electric fuel pump.

mcbchild

iTrader: (1)

I just got my carb back from the shop and was told that it had a blown power valve and and the air/fuel mixture settings were not set correctly, but nothing else was found bad or wrong with the carb. I also replaced the carter mechanical fuel pump for an Holley black electric fuel pump w/regulator. SO now I will see what it does at the track this weekend.

mcbchild

iTrader: (1)

ttt

mcbchild

iTrader: (1)

Nope, didn't make much difference. Could it be something wrong with the heads? I did overheat the engine a couple of times when the water pump belt fell off a couple of times. but i did a compression test and was 180psi in one cylinder a close to 190 psi in the other cylinders. no white smoke or anti-freeze in the oil and vice versa.

doc221978

Maybe you can try checking the timing mark. Make sure the piston is at TDC and see where the timing mark is actually pointing. Seen it a couple times.