Hi all,
I was trying to follow the instructions from the dodgetravcos site and set timing 0n my 440 to 38 BTDC at 2600-2800 rpm.
I just cant get there.
I have a 440 with a Comp Cams 280H cam and a Street Demon carb (the newer Thermoquad/Quadrajet hybrid style)
When I turn the idle set screw all the way down I only get 2350 rpm.
Car seems to run fine, has good power.
What am I doing wrong? Is something limiting the idle mixture screw at idle in Park?
can I just set 38BTDC at 2350 RPM.
Any help or advice would be greatly appreciated.
Thanks
Vic

lets get started, what is the lowest good/stable hot idle speed you can get & what is the initial at that point? ported or manifold timed?

Are you trying to tune this motor for a car or motorhome? If for a car with stock distributor set the total mechanical timing at or above 4500 RPM in nuetral, make sure and disconnect the vacume advance hose to the distributor when setting the total timing. I like and use the initial timing to be set at or near 14 BTDC to 18 BTDC idling in nuetral below 1000 RPM That usually requires shortening up the mechanical advance slots in the distributor by welding them up and changing the length of them to be able to get 34 to 38 degrees total timing
IHTHs

Bear with me, I am learning.
I set the timing with the ported vacuum blocked. I need an idle speed of about 950-1000 rpm (18BTDC) in park to get 850 in Drive with the lights on. (otherwise it dies)

This engine is in my 1973 Charger.
Darn, was I was supposed to do this in neutral? Well i'll try again.
I know I look dumb here, but all my other old cars are manual transmissions so I had to know less to get them to run... I guess.
The dodgetravcos site was just a link I found.
Thank you
vic

we're all learning bro. the lowest hot idle speed in drive you can get is 850? Can you bump up the initial to where at the lowest idle speed you can get from doing that showes no/little vac from the ported port (some cans take more in hg than others to start)? You want no adv at idle and for the springs to start ~100-200 above the idle speed, using just the single stock light spring with one coil cut off might let the adv start ~1000 RPM. with the initial timing set you can then shorten the slots to get 36-38. FBO has the plate for $25 which is a quick & easy alternative to welding/filing the slots. Edit Yes set total in neutral (cuz it is high RPM so no need to have it up on blocks (in drive) & revved to the moon), initial timing set in drive as that is what the eng will see stoplight to stoplight so you want to replicate that in your driveway

I can get lower than 850 in Drive, but not with the lights on. This cam seems to be unhappy with any accessories or lights on. My builder put in it and I didn't think to ask about what it would do to daily drivability.

Tell me again about the vacuum, I have a vacuum gauge in the car and I use one to tune, but I always disconnect the ported vacuum. So I think you are saying I want to bump up the initial timing (at operating temp) until ported vacuum drops to zero. Is that right?

put the gauge on a manifold port & bump the initial up till you get the highest vac reading you can, all the while slowing the eng back to 850 in drive (or even a bit lower than 850 if possible) but not a deal breaker as it sounds like 850 in drive is as low as it can go for a good stable hot idle with the lights on, then retard the TIMING slowly till the VAC drops 1". at that point your initial you have that is your IDEAL initial that your eng with all its uniqueness/intracies wants/needs. 18-22 initial might be a good range but post what you get. at that point see how much vac the ported port has and plug in the can & see if the timing jumps. More later, I'm gonna hit the hay in a minute. the stock car might be finished/running tomorrow

got it, I'll post an update tomorrow. good night

Do any of you guys ever read what the original questions?
He is trying to get the curb idle screw to run the engine up to 2800 rpms.

To answer your question. Manually move the throttle by hand to the 2800 rpms. Then adjust the timing to where you want it.

Digger73 (Mike)

No we dont read the original Q's, we just wing it! (relax bro we'll get there). it was a slight bit ambiguous (at least to me) so I just started from scratch to see how it developed

Rapidrobert,
I just set it up as you suggested. 1" less than maximum vacuum gets me 16.7 BTDC initial timing on my digital light at 830-850 in drive

Nothing ambigious here! & no offense was meant by my (prior) comment, I was more complaining about the complainer. OK, plug in the can to ported & see if it gets activated (we're hoping not) and see what springs are in the dist (OE is (1) light one and (1) heavy one with an elongated loop on one end) & you'll need to bump the eng over or use a 1&1/4" socket on the big front bolt (if hand turning pulling the plugs sure helps. is this a BB? How would you like to shorten the slots (weld up/file down-a pain or the FBO plate-$25 to your door, it does work well & has 10-12-14-16-18 deg slots & is a drop in deal)

Initial timing hot at 850 in drive was 22BTDC making maximum manifold vacuum (14.5-15). When I retarded it to get a 1 " hg drop (13.5-14.5), I get 16.7 BTDC (sorry this was before your very last post) I'll check the can now

yes. it is a 1969 RB block. I looked at the FBO site and unless I'm reading it wrong, those plates are for an FBO distributor. Will they work in a stock distributor as well?

Yes, I just checked their site and their instructions are a bit ambiguous as their wording saying that the instructions are for FBO dists only might (easily) lead a person to conclude that the plate only works on their dists (& cost them sales as I'm sure you're not the only person that came to that conclusion). Actually it is good for ours & that one J685S is the one you need & the spring kit for $10 would likely be a timely purchase (not sure what tension they are but likely are in the ballpark & are for sure needed).

I checked timing with and without ported vacuum connected. There was no difference.
I turned the car off, took the distributor cap off and pulled vacuum with a Mitivac to see how the vacuum advance was set. The vacuum would start moving the floor at 12 hg and stop around 20ish. So although my advance didn't visibly change when I was running the car, the vacuum test tells me vacuum advance should have been starting to kick in since I idle around 12-15'hg

Thank you Robert. This will be my next mod!

Close Brando, ported vacuum doesn't provide vacuum at idle. It kicks in at part throttle. You're actually in good shape here.

yes there should not be any vac on that ported nipple (& we dont want to have to tune for manifold vac) but with the idle speed being a bit high I just wanted to confirm that we are still on ported.