In my ongoing process of trying to find out where my vibration and (I think) lack of power is coming from, I shot an infra red temperature gun at the beginning of each cylinder's header pipe while engine was running. (I was looking for a cylinder or two that ran significantly cooler thatn others.)
The passengers' side (cylinders 1-4) ran between 220-280 degrees, the hotter being at the rear of engine. The drivers' side ran almost 100 degrees cooler, again the hotter temperatures at the rear of engine. Has anyone else experienced this?
The cooling fan does seem to blow more air over the drivers' side. Maybe this explains the situation.
By the way, all spark plugs look good (chocolate to gray.) And all cylinders have 165-170 compression.
Any input is greatly appreciated.

 

what vehicle do you have and what engine do you have?

 

it is a 1967 F100 with a 1971 block 460, just rebuilt with 10.5:1 KB pistons, CompCams HiEnergy cam, Crower hydraulic flat tappet lifters, Harland Sharpe roller rockers, 1969 D0VE C heads, Jet Hot coated L&L headers. MSD distributor and wires. Stock Ford fan with new non-thermal viscous hub. Edelbrock Performer manifold and 750 CFM carb. Accel super coil. It has a C6 rebuilt with extra clutch discs and a 400 RPM over stock torque converter. Sure appreciate any advice. Thank you.

 

What are your symptoms? You say lack of power, always, @ a given rpm, when hot or cold, more information would be helpfull. What kind of vibration? Does the motor run good when cold and then get rough when heated up? Check for vacuum leaks and also make sure your not passing to much heat from the intake up to the carb. Mabe be helpfull to put a carb plate between the two.

 

It feels to me as if it is not firing on all cylinders. Though all spark plugs seem to be same good color. Vacuum gauge hooked up to manifold port fluctuates rapidly at all RPMs. New harmonic damper. Timing advances okay according to timing light. It does seem to run much stronger at 18-22 degrees BTDC. Many people say that 12 degrees is more normal for this setup. It just doesn't feel smooth, or put you back in your seat the way I think a 450 HP engine should. I idled engine and squirted alcohol/water mixture on joints between manifold and heads, etc. with no noticable difference. Could still be a vacuum leak on bottom of joint between intake and heads, I guess. Seems to perform about the same hot or cold. Starts right up, though. One interesting thing--the clear plastic fuel filter I have mounted between stock mechanical fuel pump and carb never seems to get full. When I disconnected the fuel line, and cranked engine over, there was not much of a stream of gas that came out. I ordered an electric pump, but have not yet installed it. I appreciate the help. Thank you.

 

Check the timing......18 - 22 degrees is a whole lot. I would put money on the cam, timing chain, distributor set up. Was the timing chain, cam, crank set up properly? Is the distributor off a tooth or 2? That's where I would start. Bring the #1 cylinder to TDC and see where the distributor rotor is pointing.

 

I have exactly the same symptoms with my 77 460! Can't wait till you get it figured out, I haven't solved mine yet. See my post replys to "5 cylinder 460" maybe they will help you.
Good luck!
007BRONCO

 

I was having a similar problem.

Mine was a lean miss fire.

 

18 - 22 is not to bad for a modded engine my EFI 460 Runs good at 15 to 17 if I could get gas to support it it would perfer 18 to 20. But mine isn't stock any more. I can't swear to it but is almost sounds like a cracked Intake manifold or a major vac. leak. Just keep searching and let us know what you find. I am now curious.