neat. it runs a little better.
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From: Thunder Bay
neat. it runs a little better.
I replaced my afc with the one off my old pump with an unmodified afc foot (basically changed off idle fuel to less than stock. Motor now has less off idle fuel). I also run a afc top with a milled and drilled smoke screw area so I can dial it back right to the top of the dennyt#1 pin. I then put a tighter afc spring in (the stock green spring, as opposed to the stock red spring) and changed a couple of the other guts in the old afc pump top and put them in the new one. I run a longer guide pin for the fuel cone. I use a needle bearing that is longer than the bosch part and it gives me more adjustment in conjunction with the dennyt1 pin. I also clipped my governor spring (3800 spring) and drilled the case for an 1/8npt so I can hook a gauge up to it and keep an eye on case pressure after I swap my head with the p&p one
The AFC mods seemed to change the dynamics of the motor bigtime. It runs a lot nicer and first impressions are that it surges less as well. I'll drive it a bit more tomorrow and see if that's actually true. I wanted to do all this work before swapping heads because I didn't want to have to do it when it was all apart and be trying to prime the system AND dial in the fuel screw and idle. Last time I tried it, the motor ran away almost as soon as I got it running. This way I don't have to mess with the pump or worry about runaway. I can just take the old head off and put the new one on and run it with the new pushrods and valve springs and fluidampr with a pro comp pusher pump to keep fuel pressure at a constant 20psi or so, even under wot. All that will be my project for next week. And figure out why my running lights and dash lights stopped working.
I'm hoping the afc stuff I did today and the new head will cure my surging once and for all and maybe unlock a couple ponies as well.
All in all I think I have a fairly custom afc and I like it. This setup that I got today seems to work better with the a4000 than the setup I had on before. The differences are minor but sometimes a small difference in tuning makes a big difference in drivability. Only differences are the slightly stiffer spring and I don't have a mildly shaved afc foot anymore.
fuel screw is 1/4 to 1/2 turn from high rpm hanging. Boost seems to be about the same as before but it seems stronger at wot than it did before, maybe it's just a placebo effect. max psi is still in the 46psi ballpark
No pictures yet. I'll take some pictures and do it all up nice when I put the new head in. Make a thread and show y'all what exactly I did with dyno numbers for results eventually.
The AFC mods seemed to change the dynamics of the motor bigtime. It runs a lot nicer and first impressions are that it surges less as well. I'll drive it a bit more tomorrow and see if that's actually true. I wanted to do all this work before swapping heads because I didn't want to have to do it when it was all apart and be trying to prime the system AND dial in the fuel screw and idle. Last time I tried it, the motor ran away almost as soon as I got it running. This way I don't have to mess with the pump or worry about runaway. I can just take the old head off and put the new one on and run it with the new pushrods and valve springs and fluidampr with a pro comp pusher pump to keep fuel pressure at a constant 20psi or so, even under wot. All that will be my project for next week. And figure out why my running lights and dash lights stopped working.
I'm hoping the afc stuff I did today and the new head will cure my surging once and for all and maybe unlock a couple ponies as well.
All in all I think I have a fairly custom afc and I like it. This setup that I got today seems to work better with the a4000 than the setup I had on before. The differences are minor but sometimes a small difference in tuning makes a big difference in drivability. Only differences are the slightly stiffer spring and I don't have a mildly shaved afc foot anymore.
fuel screw is 1/4 to 1/2 turn from high rpm hanging. Boost seems to be about the same as before but it seems stronger at wot than it did before, maybe it's just a placebo effect. max psi is still in the 46psi ballpark
No pictures yet. I'll take some pictures and do it all up nice when I put the new head in. Make a thread and show y'all what exactly I did with dyno numbers for results eventually.
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From: Orange County, California
Are you talking turbo surging or RPM surges from the 3800 spring? That 3800 spring is a touchy mother! As stiff as my rear suspension is, small, repetitive bumps sometimes cause my foot to move enough and make the RPMs surge. I've learned to drive around it and just give it some more throttle. I've been tempted to tear into the AFC of my pump and make some adjustments.
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From: Thunder Bay
No I'm talking turbo surging. I wish it was rpm surging. Mine isn't too touchy. Well going from a crazy crazy touchy 3k rpm spring in a ppump motor to this one wasn't bad at all. Plus using a longer fuel cone guide pin reduces off idle fuel which makes it less touchy too. And my afc spring/star wheel is As tight as it can be without limiting travel. It helps with the surging.
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Sent from my Galaxy SIII via tapatalk 2
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Joined: Oct 2008
Posts: 1,591
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From: Thunder Bay
I managed to dial out the smoke pretty darn good with my adjustable boost elbow on the afc line. Still hazes under normal acceleration but that's the nature of the beast with big injectors and big turbo.
New head is still waiting to go on. It still surges but not as bad as it used to. I'm hoping the new head eliminates that. Once it is all done, I'm going to guess the only thing holding me back from chasing down the 12mm ve fuel only record is a set of injectors and tuning.
Wish list is getting shorter.
New flow honed injectors
Nice water/meth system
Maybe compounds, although probably not necessary.
And the ford electronics to stop giving me grief!
Sent from my Galaxy SIII via tapatalk 2
New head is still waiting to go on. It still surges but not as bad as it used to. I'm hoping the new head eliminates that. Once it is all done, I'm going to guess the only thing holding me back from chasing down the 12mm ve fuel only record is a set of injectors and tuning.
Wish list is getting shorter.
New flow honed injectors
Nice water/meth system
Maybe compounds, although probably not necessary.
And the ford electronics to stop giving me grief!
Sent from my Galaxy SIII via tapatalk 2
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