Help with 440/purpleshaft/Holley

[moparedtn]

Wondering if any of you would offer some advice on this:
My GTX has a typical rebuilt 440 with forged internals. Only significant deviation from stock is the typical Mopar purpleshaft cam, which I think is the 509/292 one. I was not the builder; previous owner was.
Motor is fresh, however.
I am running Mopar electronic ignition (orange box) and a Holley 3310 (750 vac sec).

The motor seems to like a LOT of initial timing (like +15BTC), makes its' best vacuum there and idles best there. I have already gone up 4 sizes on the primary jets on the Holley as well - it took that much to get it to smoothly take throttle.
I have disconnected the vacuum advance on the distributor.
Consider everything to be new on this engine because, well, it is.


Surely many, many others have gone this route with the electronic ignition and Holley on this very popular cam.
I'd like some advice on ballpark setup for the timing, advance, etc. and on dialing in the carb as well.
Any help from experts out there?

 

[Badvert65]

That cam works best with a higher stall converter. I have set up nearly the same thing on a 69 Charger (509 cam and the 3310 Holley). We ended up with a 3500 stall and 4.10 gears but it runs awesome.
FYI, I am not certain what the initial timing is set to, maybe around 12 BTD. The distributor is stock Mopar, with one 'light' factory spring and one 'super lite' MR Gasket spring (basically replaced the factory 'heavy' spring), Mopar 'Chrome Box', and we set things up by setting the total timing to 36 degrees at approx. 3000 rpm (We have a mark on the balancer per the Mopar racing manual).
Also, make certain that there is absolutely NO Play in the accelerator pump linkage or you will definitely feel it (hesitation).

 

[moparedtn]

Thanks, Matt. I had an old thread on this topic and I guess I should have continued with it, but didn't think anyone would see it.
I have a 4-speed in the GTX. The 3310 is stock except where I changed out the primaries to 75s, which helped a ton.
It does respond to idle screws, so that's good, means the throttle blades are in the right neighborhood at idle.
I've made sure there's no slop in the accelerator pump linkage, too.
Boy, the engine sure dances in there...
I'm getting about 11hg vacuum @ idle, can't complain about that.
I've disconnected the vacuum advance on the distributor, which helped a bit when pulling hard.

I guess what I'm asking for here is for someone to say "go buy these advance springs, set this to that, change this part in the carb to that", etc.
This has got to be a real common combo on these, right?
I know the old purpleshafts aren't the most efficient or modern of designs, but surely folks live with them today?

 

[Badvert65]

The 69 Charger is still running strong with that cam. Being a 4 speed, you should be fine there. I have been setting up my distributors the same way for more years than I can count and it seems to be fool proof. On a factory distributor, there are two advance springs, one thick and heavy, the other smaller and lighter. Leave the smaller one in place, replace the heavy one with a light spring from a distributor advance kit (Mr.Gasket, Summit, etc). This will give you a stepped advance that is all in by around 2500 rpm (more or less). Then, with the engine warmed up, run it up to at least 3000 rpm (to get all of the advance in at the distributor) and set total timing to about 36 degrees.
You can play around with the accelerator pump squirters. You'll just have to see what your engine likes. We have been running the pink cam (not certain of the color-the only one with 3 screw holes) and I run #31 squirters the Charger runs #35.
I can't recall which main jets we use, 76 or 78 likely. Also, we use the 6.5 power valve (standard in a 3310).
The Charger runs 11's in the quarter all day in street trim. My 65 Sport Fury runs 12's all day in street trim. I will be putting the same combo in a 65 Belvedere bracket racer this summer.
It works for me so I am sticking with it.

 

[moparedtn]

Awesome stuff, thanks!
Do you run the vacuum advance hooked up? If so, is it hooked up when you do total advance @ 3000rpm?

 

[lewtot184]

my best advice is to throw that came in the deepest river you can find,... ok i know that won't happen,..lol. get on the FBO website and look at their distributor advance limiter plate and springs. you can run a vacuum advance, i do, with a hotter cam.

 

[Badvert65]

Awesome stuff, thanks!
Do you run the vacuum advance hooked up? If so, is it hooked up when you do total advance @ 3000rpm?

Set advance with Vacuum disconnected. I thing think the advance is connected for 'normal' driving on the Charger but my Fury has a tunnel ram and I set it up not to use Vacuum advance.

 

[Ron Ward]

You didn't say whether or not you had the exhaust crossover blocked off under the intake. Mine is blocked off and I had to compensate by increasing the primary jet sizes to accommodate.

Yes, I do run with my vacuum advance disconnected and I removed the heavy mechanical advance spring and threw it away. I run 36° total advance and let it eat. My setup is similar to yours with 3.91 gears and a 4-speed transmission. I am shickled titless with the performance.

One thing I have noticed with the old DC cams (mine was purchased in the early 1980's) is they idle like a AA fueler when they are cold. Rough, choppy, and unruly until they warm up.

 

[moparedtn]

You didn't say whether or not you had the exhaust crossover blocked off under the intake. Mine is blocked off and I had to compensate by increasing the primary jet sizes to accommodate.

Yes, I do run with my vacuum advance disconnected and I removed the heavy mechanical advance spring and threw it away. I run 36° total advance and let it eat. My setup is similar to yours with 3.91 gears and a 4-speed transmission. I am shickled titless with the performance.

One thing I have noticed with the old DC cams (mine was purchased in the early 1980's) is they idle like a AA fueler when they are cold. Rough, choppy, and unruly until they warm up.

Factory 4bbl intake, no block off.
You don't have any return springs at all on the mechanical advance weights? What the heck makes them come back? :happy11:
Yeah, she pops right off when cold but is surly and rough until some heat has built up; won't take throttle hardly until then.
Previous owner put the big headers on it and ran 3" all the way back to boot. Thankfully, he did put a pair of flowmasters on it so it doesn't totally run you off, but she's plenty rowdy.

- - - Updated - - -

Set advance with Vacuum disconnected. I thing think the advance is connected for 'normal' driving on the Charger but my Fury has a tunnel ram and I set it up not to use Vacuum advance.

Ok, if I understand correctly here, I'm going to mark the balancer at the 35 degree BTC point and set timing @ 3000rpm there then (with vacuum disconnected), right?
This is definitely a street car. No racing in its' future. I like a lopey idle, but I want to be able to drive the thing on pump gas anywhere and everywhere.

- - - Updated - - -

my best advice is to throw that came in the deepest river you can find,... ok i know that won't happen,..lol. get on the FBO website and look at their distributor advance limiter plate and springs. you can run a vacuum advance, i do, with a hotter cam.

Please forgive, not familiar with that site. Can you link?
Yes, if it had been me building the motor, this cam would not have been in it - more like a Comp 292 or some such.

 

[Badvert65]

Yes, set the timing as I described (with vacuum disconnected) then reconnect the vacuum. You will not have any trouble with street driving per se, the Charger and Fury are regular fun drivers (not daily).

 

[Meep-Meep]

What you are seeing is very typical of the 108 LSA cam. I'd go back to the 72 jets as a baseline (stock jets for a 3310) but about a 4.5 power valve. If you have the stock PV it may be opening too soon causing a very rich condition off idle. Idle stop screw should be maybe 1 turn out from throttle blades fully seated and if not then crank up the initial timing until you get the idle around 1000 RPM. Then you must check the total timing and adjust the mech advance so it's all in by about 2000 RPM. Vac advance hooked to the ported port is good but make sure no vacuum is present at idle. You may have to limit the vac advance too, or worst case, if the engine doesn't like it, disconnect.

 

[moparedtn]

What you are seeing is very typical of the 108 LSA cam. I'd go back to the 72 jets as a baseline (stock jets for a 3310) but about a 4.5 power valve. If you have the stock PV it may be opening too soon causing a very rich condition off idle. Idle stop screw should be maybe 1 turn out from throttle blades fully seated and if not then crank up the initial timing until you get the idle around 1000 RPM. Then you must check the total timing and adjust the mech advance so it's all in by about 2000 RPM. Vac advance hooked to the ported port is good but make sure no vacuum is present at idle. You may have to limit the vac advance too, or worst case, if the engine doesn't like it, disconnect.

I've got both the stock PV and a lower value one I bought when the vacuum was only like 6hg on the previous 440.
The stock PV is in the carb now, since I have around 11hg on this motor.

This 3310 came with 70's (!) for primary jets new out of the box!

I have 75s in it now and the engine liked that change more than anything else I did, other than unhooking the vacuum advance. Timing right now is at the end of the indicator scale, approx. 17BTDC.
Highest vacuum was found there and she takes the throttle better there, although I'm pretty sure I'm hearing detonation (sounds like oil starvation in the rockers when I rev it hard, but it's detonation).

I need to either find and install a degree tape for the balancer or buy a timing light that dials back as needed, I guess.
No idea if the tape will stick to the balancer...
Also sounds like I need to get the lightest springs for the mechanical advance, so I've been trying to find a MrGasket set somewhere local.

Thanks everyone! I'm gonna get this right or toss the dang cam, one or the other.

 

[Badvert65]

For street, use one light Mr G spring and the one lightest factory spring. This will bring mechanical advance more gradually. If you are seeing detonation, you better back the timing down or get better gas. you might also check your balancer to see if it has shifted (outer ring moved). Bring it to TDC #1 and look to see where the marks fall. They should (ideally) be right on or close.

 

[Ron Ward]

There are two springs in the distributor for the advance weights. I remove the heavy one and just run the single light spring.

 

[moparedtn]

There are two springs in the distributor for the advance weights. I remove the heavy one and just run the single light spring.

Heck, I didn't even think that was possible, like the weight would just stay out there or something.:tongue8:

Well, I made the rounds today of all the parts stores and nobody had the "right" springs (or a timing tape), of course (living in BFE, after all), but I did manage to score an ancient "Make Waves" (MW) kit for GM distributors that has all kinds of different springs in it. I'm going to try and match one up to the light one in the distributor.

I'll then make a mark on the balancer at approx. the 35 degree mark and see if I can make it hit it @ 3000rpm, then see if THAT works out that the idle speed screw is around one turn from closed butterflies/holds an idle while doing so.

Maybe then, if only then, I'll try hooking up the vacuum advance again....

Did I forget anything?

 

[hunt2elk]

Mallory makes their 9014 advance spring kit that is what your distributor should need. Comes with 9 springs and some plastic gauges to adjust the mechanical advance limit. If you can find a Mopar P5153446 kit, it is the same except has double the gauges. This kit has been discontinued but you may be able to find one. If your motor likes a lot of initial, you will probably have to limit the total to stay under 35*.

 

[moparedtn]

As an aside, the cam is a known purpleshaft but I'd about bet the farm the builder didn't advance the cam any.
Probably what I'm fighting here, really?

 

[Ron Ward]

These are a great addition to your toolbox. No need for timing tape or "guessing" where the 35° mark should be.

http://www.sears.com/craftsman-advanced-timing-light/p-00914065000P?prdNo=1&blockNo=1&blockType=G1

 

[1967coronet]

Ed, Glad I ran across your post/ thread.
Sounds like you have received some real good help, Man I like that X.
Timing Tape........... Brake clean on a rag to clean the balancer & a little thin line of weather strip adhesive before you lay the tape on it.
{the adhesive on the tape sux}

talk to you later, riptwo0/Dan

 

[Meep-Meep]

Regarding the advance weight springs....Don't make them too loose. If you do the weights will try to work at idle and that will mess with the timing and idle quality. I keep the one heavy spring with the long slot but make sure it comes in at the very end. Ideally you want that heavy spring to give the last two degrees on the top end. This keeps the weights from bouncing by keeping a slight preload on the advance assembly.