home cut DVs

well then im stuck where i am because my AFC is as '*****ed' out as it can go right now. haha.

will the fuel plate not restrict/control initial fuel as well? or just give the fuel a controlled 'ceiling' to hit on the top end?

ive done all the typical mods the AFC, but haven't spent much time dialing it in. still lots to be done and learned in that area.
 
Your "smoke screw" in the back of the AFC controls "pre boost" fueling. Try backing it out a bit, that should help. Btw that car is awesome!
 
turbominivan said:
well then im stuck where i am because my AFC is as '*****ed' out as it can go right now. haha.

will the fuel plate not restrict/control initial fuel as well? or just give the fuel a controlled 'ceiling' to hit on the top end?

ive done all the typical mods the AFC, but haven't spent much time dialing it in. still lots to be done and learned in that area.
Click to expand...

Correct. Thats my most just take them out unless they are way overfueled.
 
The fuel plate just limits rack travel, so just like you said, a 'ceiling'. But it's more of a ceiling like putting a block under your throttle pedal so it can't hit the ground.
Then the pre-boost screw (smoke screw) will change the amount of travel you can get before hitting boost.
But both are skewed based on rpm (and gov springs), racked barrels, and fuel pressure (minimal change with pressure).
 
Just a thought if you still have too much fuel with the smoke screw backed all the way out. Someone may have ground down the afc foot thereby giving you less range to work with on the smoke screw. It is done to increase overall travel but it hinders tuning of your initial fuel setting.

Anyways just an idea. Good luck
 
gman99 said:
Just a thought if you still have too much fuel with the smoke screw backed all the way out. Someone may have ground down the afc foot thereby giving you less range to work with on the smoke screw. It is done to increase overall travel but it hinders tuning of your initial fuel setting.

Anyways just an idea. Good luck
Click to expand...

Then they did it wrong. You're supposed to grind down the front of the afc arm to give it greater travel. It's resting point would still be the same against the smoke screw.
 
Yep. It's is definitely the wrong way to do it. But it used to be somewhat common and I have seen a few like that... Used to be done instead of smaller washers on the diaphragm. Luckily not on my truck. Had a Hill billy friend that did it on his old 5spd 98 215ppump smokey pig on the bottom for sure.
 
You can rough tune afc travel with compressed air and star wheel adjustments .
I'm set to full fuel at 40psi and typically start with the pre boost screw just touching so I can make finite adjustments as I see fit . I'm using a gov spring instead of an afc spring , it allows you to better tune given the higher pressure you'll see out of the compounds .
 
haha, i used to. my first vehicle was an 89 dodge caravan with the 2.5 turbo 4 motor. i eventually had it built to about 350hp with an hx-35 and all the rest of the supporting jazz. forged, studded, ported and benched head, alcohol, built trany, 75lb injectors, and all that...
it was a blast blowing the doors off most things on the street and keeping pace with new Z06 vetts at the time in my crappy old van. i used to go to the friday night street races in it and while everyone else was getting pulled over and towed when the cop showed up, i never even got looked at.

heres the same motor after i scrapped the van and stuffed it all into a dodge omni about 8 year ago. clearly im a sucker for driving tuna cans!! haha.
it looks jankey and home built... because it was, but it sure put down the power for having about 80% of its parts home fabricated with no previous mechanical know how.
haha! good times!

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well im happy/sad to report that the new home cut DVs work, and work well.

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i broke piston 3 tonight on the way back from the car wash. no damage to the head luckily, or anything else as ive seen yet, but looks like it will get a new better short block thanks to dvst8r

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on a positive note though, the car got a 7 page feature in this issue of Canadian hot rod magazine!

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I dig the turbo mopar angle also. I used to daydream about building a turbo woody van with a manual trans.

I built a few pinto/SVO turbo (Lima 2.3) fox body cars. The dirt cheapness of all those domestic turbo vehicles back 15-20yrs ago were unreal. I've always been a bang for the buck guy, and I just like building unique vehicles. You have built one of my dream projects from better than a decade ago, sir. Congrats. It's just cool as all get out :cool:
 
I would KILL for the accessibility you have to the engine for work!

Oh and BAD AZZ car man.
 
Has anyone seen a 12v piston break like that before? I have seen a lot of broken and melted cummins pistons, but this is a new one for me.
 
^ we think we figured it out. it looks identical to all the broken pistons i got so good at replacing on the old turbo dodge gas motors.
what we think happened is, with the new DVs having a ridge left on them, and with the AFC tuned all the way tame, we think it pre-detonated on alcohol.
its spraying 2 nozzles worth of water/meth starting at 30-35psi. what probably happened is under a few high rpm jonts in first gear, with preboost fueling back way down, but boat loas of meth spraying in, it probably saw so much meth and not enough fuel that it detonated like a gas motor would.

back when with the 'full cut' 181 DVs, and a smokey tuned AFC, there was always enough fuel to keep the volume of alcohol at bay, but once the fuel has been tuned down, the alcohol volume down low became way too much.

this is the best we can figure.

going forward well try spraying starting around 40-45psi and/or perhaps just use water, or more diluted water/meth
 
Are there major vertical scuff marks on the cylinder walls?

Think of the ring getting too hot and expanding till the ends butt together and ring expands out into the cylinder wall with enough force to push through the oil film and micro seize/scuff the cylinder walls.
 
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