rack plug vs timing?

mopar or no car

mopar or no car

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Apr 9, 2008
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If I run higher timing, does the mack rack plug still bring the fuel on too soon? Unless I was already running 2k rpms or more, it would choke the engine out and make a huge cloud of grey smoke till it could build boost and rpms. I was just wondering before I take it out, if the engine would ever be able to use the fuel it added, or if it will always just choke the engine and make stoopid smoke.

Jordan
 
mopar or no car said:
If I run higher timing, does the mack rack plug still bring the fuel on too soon? Unless I was already running 2k rpms or more, it would choke the engine out and make a huge cloud of grey smoke till it could build boost and rpms. I was just wondering before I take it out, if the engine would ever be able to use the fuel it added, or if it will always just choke the engine and make stoopid smoke.

Jordan
Click to expand...

Whats your timing set at now. Sounds like it should be advanced some.
 
Well, if it ended up where I wanted it, it should have been 16-16.5*. I'm thinking of setting it at 18-19* this time and see how it runs. Click on the video in my sig and look for other clips by same person and you can see the grey smoke. I'll try to post a direct link to it.

Jordan
 
http://vids.myspace.com/index.cfm?fuseaction=vids.individual&videoid=29266434

http://vids.myspace.com/index.cfm?fuseaction=vids.individual&videoid=29266616

Hard to tell from the vids, but deffinately runs worse when its full throttled like shown. At part throttle it is alot snappier. I lost to another dodge on the street when we both took off at bout 30mph and I punched it out of habit, it acted stoopid-stumbling and cutting out and white smoke, down shifted to bring the rpms and boost up, but was to late. Common opinion is that the rack plug allows too much rack travel, and am prob going to take it out, unless more timing will help burn the fuel better. Its just a pain to not be able to floor it instictively.

Jordan
 
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You don't want to use the mack plug on the 215 horse pump anyways. It doesn't likey. Also the rack plug won't change anything at part throttle.
 
So far as I understand it the rack plug allows the 215 pumps to retard timing during the added rack travel the plug allows. I think this can be compensated for by adding more static timing advance but not sure it's really optimal. I'd say as low is your timing is that it's definitely not doing anything for you.
 
Put the AFC back together, mod it a little and put the stock rack plug back in. It will run much better, and you can stomp on it

I believe Smokem measured the timing retard in the 215 plunger @ a max of 4° so at full rack travel you are only seeing 12° :bang
Works well with nitrous though. But you need to tune things
 
definately put the AFC back in and get it dialed in right... mod it for more rack travel.

and crank the timing up... that popping and white smoking w/ light load, high RPM, no boost is classic low timing symptoms.
 
Thats kinda what I was wondering if I had a timing prob, or if it was the rack plug or both. Been hard to tell though as its been in the garage most of the time since december. I was going to set the timing again, but I blew the head gasket and parked it till I had some extra pennies and the city was somewhat pleased with my front yard. I dont have the timing tools, so I kinda winging it. I put the rack plug in before I read about how it doesn't work in a 215. Anyone want to buy a rack plug, its coming out.

Jordan
 
Too much fuel with no boost. Your flooding the engine. Adjust the AFC to limit your low boost fueling.
 
Near as I can figure, with my timing pin being off by 1/8 inch(1.55*) and the retard notch in the plunger(4*), when I stomp on it my timing was dropping to 11*. I'm going to see where the timing slipped to before I reset it just for s&g. It was so bad that I could barely start it floored, and before when it ran good, if I gave it too much throttle when starting-it refused to start. Limping it home was a huge pain. I've never drove anything that ran so bad. At first it ran like I blew a boot of and could manage about 40mph. Closer to home it got much worse. The last 5 blocks it looked like a bank of fog rolled in-couldn't see a thing. We were laughing or buts off and the nieghbor ran out of his house to see what was on fire. It was puking oil from the head gasket right above where the kdp strikes. Kinda stopped laughing when I saw the trail of oil.

Jordan
 
I checked the timing, it was 30* AFTER tdc.:hehe::hehe::hehe: Going to 19* before. Slight change.

Jordan
 
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