MSD recurve.

[Animal]

Hi Guys,

Got a 440 motor , Crower cam, intake duration 294 509 lift , ex duration 302 509 lift , mighty demon 750, eddy performer rpm intake, 10:1 compression.

Motor seems to like around 30* initial , 34 total, all in @ 3000 revs, I know your gonna say thats a high initial ,but it's were I get the best idle & seems to burn all the fuel. (no stink out tail pipes)

I've got the mopar leccy dizzy & orange box ,were the initial is set to 20* & total 34*,would like more initial but starter kickback is an issue any more than 20* initial.

Gonna get the MSD 6al & the MSD 8546 dizzy. The distributor can be tailored to a number of advance curves ,problem is the minimum is 18* which will give me 34* total & only 16* initial.

So I ordered the Msd starter saver,which retards the initial by 10* or 20* below 800 revs ,which should overcome the kickback @ 34* when I lock the mechanical advance up.

My only concern is detonation up to 2800 revs, I figured some motors use vac advance which takes the advance up to 50* below 3000 revs , so I should be ok.

Failing this , can you recurve the msd distributor to have around 10* or lower, as they only come with three recurve stops.

Thanks guys.

[Chryco Psycho]

with that cam I would think it will want over 25* initial timing , you could probably make a bushing for the MSD to trim the curve to 10* or you could weld up the slots in a stock dist
another trick is to block the idle air bleeds with a piece of wire to increase vacuum in the idle circuit to improve idle quality

[Animal]

Ok, so if lock the mechanical up & set it to 34*, all should be ok.

I've already drilled the idle air bleeds larger,to help with the rich idle, just thought if you make them smaller it will richen it up.

This motor is used on the street & strip, I don't wanna loose any power by eliminating the mechanical advance.

Thanks.

[Chryco Psycho]

locking it totally will make it hard to start & will soften power in the lower RPM but will work , I would try to make a larger bushing to limit the advance for the best results

[Animal]

Gonna fit the MSD starter saver, which will retard the initial on start up.

Do you guys think the MSD will clean the idle up when using bigger cams , cos if this is the case, it might just solve the idle problems I have.

Been looking through forum @ all the MSD posts, & noticed a couple of guys were having problems with the motor cutting out when stopped @ a red light, the motor would start back up but be a pain to get it to pick up, took around 20 seconds. this is the problem I have, but there was no answer on the posts. I think my problem is ignition, maybe orange box or pick up? hopefully the problem will go away when the MSD goes in.

BTW, don't think it's fuel, as the fuel bowls are always full when it does it, also the same happens when I changed from an 850 to 750 mighty.

Thanks.

[greenrt_se]

anybody make bigger bushing for msd distributor

[firefighter3931]

The black bushing should work pretty good.....that will give you 18* at idle. The idle circuit on your carb might need some fine tuning....

What's the duration at .050 on that cam ? The seat timing is very similar to the MP 509


Ron

[Animal]

How will I know the duration @ 50, can't find it on the cam specs?

Thanks.

[firefighter3931]

How will I know the duration @ 50, can't find it on the cam specs?

Thanks.

I guess you didn't get a cam card ? I looked on the Crower site and came up with grind # hdp294 and the corresponding part # is 32206. Is this your cam ?


specs :

294/304 advertised
230/241 @.050
.509/.530 lift
108* lsa


This cam is gonna be a bear to tune.....lots of seat timing and overlap with the 108lsa. How high is the engine idleing at ? If it's over 1000rpm you are using the main circuit and not the idle circuit. When tuning if the idle mixture screws have little effect you are exposing too much of the transfer slot. You need to get an idle vacuum reading and size the power valve accordingly. Lots of things to look at....



Ron

[Animal]

Ron , you're spot on, just found the cam card.

Got the motor running @ 1000 rpm in park & 900 in drive, I know what you're saying about the carb, but i think it's @ it's peak cos I can't get the throttle blades down anymore, so the transfer slots are not even exposed.

I rephased the rotor cap, cos it was firing between the towers, seems to be a problem with mopar dizzys

Got 11" vac in gear @ 900 rpm & 12" to 13" in park @ 1000 rpm , the demon power valves are 6.5 " hg.

Got a vac gauge coming from Summit, which I'm gonna fit in the car, to see whats going on when under load.

Gonna fit the MSD anyway, think it will clean the idle up a little.

Don't get me wrong , the motor is very responsive, low 12 1/4 mile.

I was told the cam may be the cause of the ideling problems (cutting out for no reason @ idle) as the exhaust duration is longer than the inlet , causing the fuel to sit in the intake due to lack of exhaust scavenging.

Got the TTI   3 1'2 headers, 3" complete system with X pipe.

Was running NGK 6 heat range, now got champion 9 heat range.

Drilled the idle air bleeds out a nats, which helped with the idle , as it was rich with even 1/2 turn on mixture screws.

The motor idles very stable @ 1000 rpm, no real shakes, but concerned with it cutting out for no reason when driving , never  happens when i run it in the garage for long periods.

Ron, when you say it's a bitch of a cam, what are the problems with it?

Thanks again.

[Animal]

Meant to say, the problems with it cutting out whilst pulling up to a red light , were there before I made any changes to the idle air bleeds.

If this cam grind is a bear to tune & is gonna give me no end of troubles, then what cam would you recommend & were would i get it from, I realise the lifters would also need changing.

Could another cam give me a better time on the track, or is the one I'm running a good cam, but a bitch to tune when idling , got a 3200 convertor & 3.9 rear gears.

BTW, i have the eddy alum heads.

Thanks.

[firefighter3931]

Animal,

Sounds like you're on top of things.....thanks for the detailed info.....that clears things up. Based on what you're describing, it's performing about as good as can be expected. I've run cams with less vacuum than yours but it takes some work to dial in as you're seeing.

By difficult to tune i'm mainly referring to idle quality. At this point, the "if i were you" answer would be a multi spark box (MSD/Mallory/Crane) to help clean up the idle....I use MSD, personally. The multi spark boxes really make a huge difference with big cams that have lots of overlap/duration. With regards to split grinds....the extra lift and duration on the exhaust side helps the cylinder to scavenge better when intake/exhaust flow balance is below 70%....which is the case with oem iron heads. The E-heads are very close to that ideal 70% so a split grind isn't as critical in that application.  There's nothing wong with that cam in your combo and it is well matched to your stall speed and rear end gearing....good job on the parts selection. 

The NGK bcp(r) 6es is the plug to run with an E-head (pump gas compression) and MSD ignition system....Vegas Mike has that setup on his e-headed 446 that is running the Comp xs282s solid with 244*@.050 and it idles at 800 in gear. Mike is using the black bushing for 18* initial and 36* total....runs fantastic !  The MSD superconductor 8.5mm wires are far superior to anything out there....resistance is 50 ohms per foot. The Blaster coil is worth getting also.


Ron

[Animal]

Thanks a bunch guys.

Ron, you must be reading my mind , as i've got the blaster 2 coil , msd 6al, the 8.5 leads & the MSD starter saver , as I would like 20 to 25 initial , 35 total @ 3000revs, is this ok? 

This should be with me by monday (coming from summit)

Certainly put my mind @ rest, as going by what your saying, the idle is set up fairly good considering the cam specs.

Just hoping the MSD will solve the cutting out deal.

Again, thanks Ron, always good to hear from you.

Adam.

[firefighter3931]

Ron, you must be reading my mind , as i've got the blaster 2 coil , msd 6al, the 8.5 leads & the MSD starter saver , as I would like 20 to 25 initial , 35 total @ 3000revs, is this ok? 

Adam, those parts should do the trick. I would use the black bushing which s the largest that comes with the distributor and try it out. Set the base timing at 18*-19* and see how it runs. This should give you 36*-37* total which is fine for an aluminum head build.

The orange box is not really designed for your application and there have been problems with them over the past few years. My 6-pack r/t was idleing like a sick puppy....pulled a plug wire and grounded it to check spark.....got a dull orange arc....bright blue is what i like to see. Swapped out the box for a 10 yr old piece i had on the shelf and the difference was dramatic. MP quality has gone into the toilet over the past few years and the orange boxes are hit or miss.....many of them crap out or run poorly.   

You will see a big difference....i would bet on it. 

Just follow the installation instructions and you're golden. Let us know how it turns out.



Ron

[Animal]

Gonna set the timing as you suggest, cos thinking about it , if the spark from the box is pants, this is the probable cause why it appears to run rich, as the fuel is not being burnt completly.

Fitted the FBO box the other day & noticed the rpm came up 200 over the orange box, checked the timing to find it hadn't moved, so there was an improvement with that box. This is when I tried to get the idle back down to 1000 rpm to find I had no more on the curb idle & it was off the stops.

Only concern now, is when I fit the MSD, the rpm may come up to much @ idle, the only way I can figure to get it back down to 1000rpm would be to retard the timing or get another set of air bleeds , as I've already made these larger.


Thanks Again

Adam

[firefighter3931]

Gonna set the timing as you suggest, cos thinking about it , if the spark from the box is pants, this is the probable cause why it appears to run rich, as the fuel is not being burnt completly.

Exactly....what you're describing is typical of a weak ignition system. A stronger fire will burn the fuel and increase idle speed. 


Have you looked at the plugs ?   I'd be willing to bet that they're dark. The MSD really helps in this area....plugs stay clean longer as long as the jetting is correct. 


Your high idle speed is largely a product of the huge amount of base timing that's currently in the engine (30*). When you set your base timing at 18* the idle speed will drop and you will be able to use the idle speed adjustment to bring it back where it needs to be. 




Ron

[Animal]

The motor has 20* initial in it @ the moment, which was why I was concerned with getting the rpm down when the MSD goes in.

Thanks for all the info, will post back when I fit the MSD.

Many thanks.

Adam.

[firefighter3931]

The motor has 20* initial in it @ the moment, which was why I was concerned with getting the rpm down when the MSD goes in.

Thanks for all the info, will post back when I fit the MSD.

Many thanks.

Adam.

Adam, i don't know where i got that 30* number from....i must be getting old, LOL ! 

I still think you'll be fine with the msd box....even with 17* initial & 35* total if need be to bring the idle speed down. Fwiw, mine made it's best power at 35* total when we had it on the dyno. 

When you install the MSD, pull the plugs and give them a cleaning if need be. The gaps should also be opened up to .050 to take advantage of all that extra juice.....MSD's are like arc welders ! 



Ron

[Purple440]

When you install the MSD, pull the plugs and give them a cleaning if need be. The gaps should also be opened up to .050 to take advantage of all that extra juice.....MSD's are like arc welders ! 

Ron

I can attest to that...had bad wires yesterday when I pulled the Charger out of storage..tons of corrosion.  It was arcing from one of the plug wire boots to the metal brace that holds the cap on the distributer.  It was blue/purple and about an inch long spark!