I have a 68 Camaro with original 327/210. The car ran fine but I wanted to add some "umph" to it so I replaced the 2barrel car and intake with Edelbrock Performer Intake (2101) and Performer Car (1406). Ever since I have done that it doesn't run right at WOT. Best description I can provide is that it sounds and feels like a computer controlled car with a rev limiter. If I run at half throttle to 3/4 throttle it doesn't do it. It happens around 3500-4000RPMs. I have played with timing, carb calibration and neither made a difference. I checked the fuel pump pressure and found it to bounce between 2 and 7psi (this was at idle). I replaced the fuel pump and now it is a steady 6.5psi (again, at idle). Replacing the fuel pump did seem to help just a little. I replaced the fuel push rod also. I am wondering if the cam lobe could be worn such that it isn't providing the volume the carb and intake needs at the higher RPM and WOT? I am still running the original heads and would like to upgrade but want to fix this issue first. Please HELP!!

I see you checked timing, but did you check total timing? I would think on your car it should be between 32 & 36 all in by 3500rpm. Find a dial back timing light and give it a check. What kind of engine vac do you have? Did you plug all the not used vac ports on the carb?

Yes, I should have mentioned. Timing had been checked both static and mechanical. Vaccuum is reading 18in at idle and all undused ports are plugged.

Check the float level on the carb. My 1st 1406 was WAY off right out of the box.
Did the engine rev easily over 4K before the intake and carb was replaced?
Is the carb opening fully under WOT? Have someone hold the pedal to the floor and shine a flashlight down into the carb to verify this.

Ya know,,,,,,back in the 'old days',,,,,when ever I tried removing a properly functioning intake and replaced it with a larger system WITHOUT making any other 'umph improvements', it was a mistake. But I know nothing of your setup???

A 210hp 327 has a pretty small cam in it. You just may be running out of useable cam profile for the kind of air/fuel you're trying to shove in htere. You also may be floating the valves. Might need better springs. I'd suggest a valvetrain swap.

You may also want to check your fuel filter. It its fine under slow opening but not at a snap opening, it could be lack of fuel on demand.

Kev

Sounds like fuel restriction to me, clogged filter, lines too small, clogged pickup in tank.

Also, fuel lines in these old cars usually have at least one piece of rubber tubing at back by tank and then up front by pump. Those rubber fuel lines can crack and fuel pump will suck air instead of fuel, so replace all the rubber fuel lines with new pieces.

Another rather easy test is a static compression test. Take out all plugs and get readings to be sure all cylinders are consistent...........

Make sure firing order is correct and that your cap, rotor and wires are in tip-top shape.

Lastly, make sure you don't have a vacuum leak somewhere.

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After reading his description it ran fine before the swap. If the timing is really correct then it is a jetting issue. How do the plugs look? He may be to rich on the mains with that little mouse.

I second Travis on this one. I just installed the same carb and when I first bolted it down it was just a smidge crooked and the secondaries would not open. They were hitting the intake manifold. I loosend it back up and moved it just a smidge the other way and then they opened fine.
Don't know what a smidge is but it isn't much.

im betting the fuel pump is not giving enough fuel to feed the beast.
At least that was the problem when I did the swap years ago.

I adjusted the floats, they were off a little. Replaced the fuel pump again, this time with Edelbrock 1721 Performer fuel pump, replaced the rubber hose from the fuel line to the input of the fuel pump. Readjusted the idle mixture screws. Drove it and it wasn't better or worse, then after driving a while I decided to try again, floored it through the 1st 3 gears and this time it had no isssues at all, did it again and still no issues. I haven't driven it again but seems hopeful. Thanks for everyone's help.

A 210hp 327 has a pretty small cam in it. .
The 210 has the same -929 cam that the 327-275 L30 has, as well as a great number of other low and medium performance 327 and 350 engines, they used this cam a lot, and it will produce 300 HP with the right combination of other parts.

The "choke point" in the 210 is the heads and 2 bbl carb. The heads are lousy and should be changed. Changing them will give a remarkable performance improvement.

Switching to a 4bbl carb should have given you an improvement tho, a pretty good one even. It certainly, by itself, did not make an engine that wound up just fine suddenly not want to rev over 4k...

Since you made a change, go back thru everything you did. If the vacaum is steady and high, you probably don't have a vacaum leak. Check some plugs, how do they look? Do a WOT pull, shut it down at the top of second, get her safely stopped, and look at the plugs again?

Checking the float levels on the carb is an excellent idea. While the top is off, make sure the secondary flapper moves freely, blow thru the secondary jets, make sure the passages are clear (be VERY careful of flying gas, maybe pull the carb and dump the fuel before doing this!)

To prove it is a secondary fuel delivery problem, you could disconnect the link that operates the secondary throttles and drive it on just the front 2 barrels. It should pull smoothly to whatever was the max useable rpm with the old carb and manifold.

With the checks you allready made, I'm going to assume for the moment that this is not an ignition/timing problem.

Assuming no inlet/ carb leaks ..possible cause.
1/Very common when changing valley cover/carbs to get crape come thru fuel lines...flush, new filter. the holley sintered filter could be clogged now. possible cause.
2/ Clean valve and set float levels. possible cause

3/I would be looking at about 30/32 centrifcal (vac disconeected) all in around 3000
4/ Check pump lever clearance at WOT not critical but should have around 18/1000...This doesnt sound like your problem
5/ Jets, out of the box holley over jet, may have 66 or 68 s in, ball park jets should be 66 or 64. Again I doubt if this is the problem.
6/ Sec Stop screw...again doubt if this is the problem, this relates to idle issues
7/ Power valve..the out of the box, from memory is a 6.5...this would be in the ball park, check what u should have with in car vaccuum gauge under road test.

All the how tos for the above are in older posts and in the holley manual/web site.

my 1968 camaro had the same problem it sounds like, it would run good but as soon as my car would get up to about 4,000 to 4500 rpms it would just bust out like a rev limiter style and i did everything like you did, i went out and bought a whole new distributor and it fixed the problem, you might have something in your distributor going bad

Not sure if anyone is monitoring this thread anymore but the cause of my problem was that I had a bad lobe on the cam. Exhaust lobe was worn (not a lobe) and wasn't opening the exhaust valve (or if it was only a slight bit).

Nice find!

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excellent info. thanks for returning as some of us do try to keep up.