I am just curious what you other SB guys/gals are getting for idle vacuum numbers with your 226/238 cams.
I am currently pulling 15"hg at 975rpms in N and 11" to 11-1/2"hg in D at 825-850rpms (moderate lope) and I just wanted to see if I was in the ballpark.

Note: If I turn up the in gear idle to 900rpms, then the vacuum goes up to 12"hg with a mild exhaust note.

Thanks

sounds about what I'd expect...

Most people with cams like that set there idles around 950-1krpm . If its street driven i'd set the choke cold idle to 1800rpm to get the lifters pumped up with oil nice and fast.

if your after a lower idle mill that thumps, you will need more timming 22+ at idle.

--disreguard, all my cars have been manual trans.

A auto matic trans is hard to get it to shift right on its own. Driven hotrods need manual bodies, because all the downshifts/upshifts are screwed.

Thanks Patrick.

Mark,
I run 24 degrees of initial timing for your reference.

""good now get it right.""
What does this mean?

""A auto matic trans is hard to get it to shift right on its own. Driven hotrods need manual bodies, because all the downshifts/upshifts are screwed.""
Then you need to tune your auto tranny. The shift points can be made to just about what ever you want with aftermarket governors and testing different 1-2 and 2-3 shift springs. By the way, what does this have to do with my vacuum question?

all mechanical ? or vacumm advanced with manifold vacuum ? 24 mechanical is some stress at start.

You probably heard the engine come into tune. It is a valuable diagnosis tool.

It must be that I didn't test enough with my auto trans springs....I think the stall killed its driveability.

24 initial and 34 total. I run a mini starter so I have had no starting issues in three years.

""You probably heard the engine come into tune. It is a valuable diagnosis tool.""

Do you mean when I turned up the idle and the exhaust smoothed out? If so I had to turn down the idle to keep the N idle rpms low enough to keep the engine from "running on" during shut down. It does not like N idle to be above 1050rpms or it will run on. Now I have the N idle at 975rpms and it has no shut down issues and the 825/850rpm in gear idle is very smooth. This is the lowest in gear idle that I have had with this cam and the "in gear" vacuum reading only fluctuates within 1/2 of an hg.

Thanks for the response.

Run on from a shut off igition ? That would be timing. Its in its curve at 1050rpm ? causing reversion.

a carb out of tune should not cause a desisel.

24 initail is stressfull on the starter, flywheel gear ring, over taxes the battery to crank, and even stresses the crank.

try running a vacuum advance distributor. I think the HEi mopar distributor is $37.99 at autozone.

for reference, my 360, with a stock long block that's rerung, ~7.8:1 actual compression, with a comp XE262 (262/270, 218/224 at .050, 110LSA installed at 106) is set up with 18-20 degrees initial, 36-38 degrees total mechanical advance, and idles at 950RPM in neutral with 17-18" vaccuum, and drops to 820-850 in gear and ~13" vaccuum, and 750 RPM and ~11" in gear with the A/C on.

I am running a FBO ignition system and I am very pleased with it. I can't wait for Don to bring out his ballast free coil which should be ready any week now. Thank you for your responses Mark and I will keep that distributor in mind.

Patrick, if he was deiseling that means not enough timming.

At shutdown the engine stops pulling more fuel from the carb. Fuel that is left there, because it didnt have time to burn. He needs more timing provifded from a vacuum cam.

not pushing, best of luck.

FBo is great.

because I was cheap (:

I could've also spent the money on thin MP head gaskets instead of using the .054" thick ones in the fel-pro engine gasket set....that woulda gotten me up to about 8.2. the engine runs real hard for what it is, though, and does it best on 87 octane.