[Booster66]

I have a 1966 El Camino with a 327 engine coupled to turbo 400. The engine has a mild cam 202 double hump heads, edelbrock performer rpm manifold, edelbrock perform 600cfm 4 bbl carb and headman headers. I need help with the following questions;

• Does anyone know what the timing should be set at on this?
• Do the 202 heads require a lead additive to the fuel
• What gap should be used on the spark plugs.
• Carb is brand new, however when placed in gear the idle drops significantly almost to a stall. Idle when in park is about 950-1000rpm. Fuel pressure is at 5psi. Any ideas?

Thanks for the help,

 

[ccc]

the timing on those early 327 s were between 6 and 12 before tdc with the vacuum disconnected. if someone put seats in it should be fine .i have a set of the later version of those heads with the acc.holes and had to put hardened seats for the unleaded gas.as old as it is its a safe bet already done. plug gap was .035. . as for the idle problem it sounds as if the timing is retarded or too lean at idle.also on a motor that age you need to check the tdc mark as the balancer ring may have slipped making timing it hard unless you verify the tdc mark

 

[Iischris1]

+1 on the timing. In park my engine would feel and run great, but when I'd drop it into gear it'd almost stall, like you said. Just bump up the timing some and you'll be okay.

 

[ccc]

should be, but use a light not by ear fi it starts to ping you can break a piston or ring

 

[Iischris1]

I've also heard horror stories about torque converters beginning to go out, and that's a sign. If it idles well in park and you drop it in gear and it almost dies, then put it in neutral and it idles up again, you might check that, too. :beer:

 

[EdontheBeach]

run it up to 3000rpm, set the timing at 32-34btdc, then let it idle down to 700rpm; wherever your timing mark lands, that's the spot you use. (no vacum)

 

[ccc]

that works as long as the dist advance stop bushing is intact.if gone it will let it overadvance at speed and leave it retarded at idle

 

[EdontheBeach]

you're correct - in my post i'm assuming the dizzy is in good working order

 

[Booster66]

I set the timing to 10 degrees BTDC. Runs slightly better. I put a vacuum gauge on it and it runs between 10-11 inches fluctuating slightly due to the cam. Not sure what cam it has as PO just said it was a mild cam. When I drop it in gear the vac drops to less than 6 inches. Sprayed around for any vac leaks with carb cleaner but didn't find any. Is 10-11 inches vacuum normal for a mild cam?

 

[ccc]

im afraid it is more than mild.have you verified tdc yet ?. it may have a slipped balancer ring or the wrong balancer/pointer set up.but it sounds like it has too big a cam for stock motor /converter set up.

 

[Booster66]

Thanks CCC, this may sound stupid but how can I confirm TDC?

 

[ccc]

stick a big long philips screw driver in #1 plug hole ,turn motor by hand until it stops.mark the ballancer,then turn the oposite direction until it stops again and mark the balancer.true tdc will be exactly in the middle of the two marks.do not use anything like a file that is brittle and can shatter in the cylender

 

[Booster66]

Here is an update to my issue.
1. Replaced the tranny with a built up 2004R with new torque converter...still wanted to stall when in gear (Replaced the tranny as the TH400 had a cracked valve body)
2. Replaced all the spark plugs. Old plugs didn't look bad at all....still wanted to stall
3. Confirmed proper firing order and plug wires routed correctly...still wanted to stall
5. Confirmed TDC and the mark was in still in the correct location
4. Researched timing theory and moved the vac advance from ported to manifold.so the timing will advance while idling...improved the idle under load but little bit more.
7. Hooked up the vac gauge and set the carb for maximum vac at idle. Got about 2 inches...this moved the idle under load even more but still not enough.
8. Set the timing for 36 degrees at 3000 rpm....this moved the idle under load the final bit...idles now without wanting to stall.

So the trick was the combination of running the vac advance from the ported side of carb to the non ported, maximizing vac with the carb, and the setting of the timing to 36 degrees at 3000rpm.

Runs and sounds great now.

Thanks all for the help!