1966 Cutlass tuning question

Mr. King · 02-20-2007, 04:54 PM

I have a 1966 Cutlass with a 330, a 4 speed, 2 1/2 inch dual exhaust and posi rear with 3.55 gears. The motor is basically stock with a slightly larger than stock cam, an Edelbrock performer intake and a Edelbrock 650 carb.

The motor just doesn't seem to have any bottom end. It is very slow to rev and the motor doesn't really "come on" until 3500 rpms. Plus, it seems to "miss" at lower rpms.

I'm considering changing to a HEI points conversion. Anything else I should check or change. I set the timing to the stock settings and the carb is set just a little rich. The motor sounds great with a slight lope but it just doesn't pull like it should.

Any suggestions?

Oldsmaniac · 02-20-2007, 05:23 PM

What you are experiencing seems exactly like an over camming problem. You loose all bottom end acceleration. The 2 1/2 inch exhaust doesnt help either as you are loosing backpressure. I would suggest you do a tune-up with new plugs, points, rotor, cap, and maybe wires. Then set timing to specs or advance it a little. If the engine pings on premium you have advanced the timing too far. also check any vacuum lines for leaks and make sure the carb is bolted tight so the base gasket isnt leaking.....

Mr. King · 02-21-2007, 04:45 AM

From what I understand the guy that rebuilt the engine before I bought it put the W30 or W31 stock cam in it. I think that's the 400 442 cam. So it's not TOO radical.

I have a feeling I have a vac leak because I hear a "sucking" sound, but I can't find a vac line that is off or split. Any ideas?

Also, I forgot to mention it's hard to start. I have to crank it several times and then sit for 5 minutes reving it until it will idle.

number9 · 02-21-2007, 10:45 AM

Quote:

Originally Posted by Mr. King

I have a feeling I have a vac leak because I hear a "sucking" sound, but I can't find a vac line that is off or split. Any ideas?

I can't help you with specifics, but the way of finding bad vacuum lines that I hear most is to spray carb cleaner on lines you suspect might be bad while the car is running. If the RPMs go up, then you've found a bad line (or some other kind of leak).

02-20-2007, 04:54 PM	#1 (permalink)
Mr. King Member Join Date: Jan 2007 Location: Nebraska Posts: 53	1966 Cutlass tuning question I have a 1966 Cutlass with a 330, a 4 speed, 2 1/2 inch dual exhaust and posi rear with 3.55 gears. The motor is basically stock with a slightly larger than stock cam, an Edelbrock performer intake and a Edelbrock 650 carb. The motor just doesn't seem to have any bottom end. It is very slow to rev and the motor doesn't really "come on" until 3500 rpms. Plus, it seems to "miss" at lower rpms. I'm considering changing to a HEI points conversion. Anything else I should check or change. I set the timing to the stock settings and the carb is set just a little rich. The motor sounds great with a slight lope but it just doesn't pull like it should. Any suggestions?

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02-20-2007, 05:23 PM	#2 (permalink)
Oldsmaniac Senior Member Join Date: Oct 2005 Location: NJ Posts: 432	What you are experiencing seems exactly like an over camming problem. You loose all bottom end acceleration. The 2 1/2 inch exhaust doesnt help either as you are loosing backpressure. I would suggest you do a tune-up with new plugs, points, rotor, cap, and maybe wires. Then set timing to specs or advance it a little. If the engine pings on premium you have advanced the timing too far. also check any vacuum lines for leaks and make sure the carb is bolted tight so the base gasket isnt leaking.....

02-21-2007, 04:45 AM	#3 (permalink)
Mr. King Member Join Date: Jan 2007 Location: Nebraska Posts: 53	From what I understand the guy that rebuilt the engine before I bought it put the W30 or W31 stock cam in it. I think that's the 400 442 cam. So it's not TOO radical. I have a feeling I have a vac leak because I hear a "sucking" sound, but I can't find a vac line that is off or split. Any ideas? Also, I forgot to mention it's hard to start. I have to crank it several times and then sit for 5 minutes reving it until it will idle.