Fitech/crossram project

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Not planning on dams at first, but if there are fuel distribution issues, then I will definitely consider the old direct connection mods on this one....easy to remove the lid!
 
Not planning on dams at first, but if there are fuel distribution issues, then I will definitely consider the old direct connection mods on this one....easy to remove the lid!

I would guess that injection takes care of those types of issues, especially when you start getting into sophisticated mapping and can really dial in the curve. That's the one thing EFI gets right every time is the proper amount of fuel for any given situation. I'm curious to see how it handles part throttle operation.

That said, throttle body is not as finite as sequential either but it's still 'better' than carbs at adjusting the amount of fuel for a given scenario. Carburetors just don't have the same ability to trim fuel like injection does. It's like the difference between a lo and hi-res image.

What kind of injection system is it any way, speed density or...?
 
I'm not sure about the distribution with EFI, I'm thinking the cylinder to cylinder problems might still be there without dams, we shall see. If one cylinder is too rich from puddling or distribution, I'd imagine the EFI will adjust fuel trims to compensate, possibly, leaning out other cylinders excessively, it's gonna be a learning curve!
 
I think it might have fits with that plenum and two throttle bodies. That intake was designed for WOT with little to no concern for part throttle 'drivability'.

It's gonna be a long road, you'll be staring at graphs and cells a lot.
 
Agreed, the process will be lengthy & involved but the outcome might be something spectacular. As mentioned, the reasons for the dams were to eliminate (or at least reduce) puddling. Puddling that has been known to blow the tops right off the 12s. I am super intrigued with your endeavor and the performance/drivability gains that it more than likely will achieve. I have to wonder if there would be any downside to running the dams with your system. I'm planning on running the 408 with carbs for now. I don't think I'd want to take the top off with the base installed and fab the dams with fear of 1) something getting into the motor and 2) any heat issues from welding. I guess either way (installing or removing dams) will require the base coming off. Looking forward to your next installment.
 
I don't think the dams have anything to do with puddling, if anything they would make it easier for liquid fuel to get trapped, I think they are there to restrict fuel/air flow to certain cylinders. The puddling and explosions generally occur on startup.
 
I agree. The F.I. Being a throttle body is still similar to a carb. As noted, the sequential injection would fix all issues.
I don't know if the danms are there to restrict or aid/help in flow.
 
I think maybe what the dams do is dampen the pulses across from the cylinder that's firing since it's such a large plenum. Could be reversion or contamination with the intake charge maybe? I dunno, I'm not a fuel system engineer.

The diagram in the old DC book stipulates installing the dams at the far ends by the #1 and #8 cylinder and specifically says to only put them in those two spots. Those two cylinders are the furthest from the throttle bodies but are sequential in the firing order.

The more modern sophisticated cross rams like on the SS/AH cars don't have as large a plenum area, they appear almost inline like a tunnel ram and are only staggered slightly.

You could make the case the later Magnum barrel intake is similar but those only had one throttle body.
 
Progress has been a little slow, but getting there...waiting on a new tank filler neck grommet, then install tank and plumb throttle body's. All the wiring is done, also gonna do something a little nicer with the radiator mount....it's a million LITTLE things that take forever....

20161026_194250.jpg
 
Well boys, it's ALIVE!!!! some of the plumbing and wiring is temporary though...no real issues other than the intended tank pump was leaking at connection inside tank, but with the tank on the floor beside the car it was easy to fix!
 
Took the duster out today for its first cruise, but first I gotta say, it really doesn't like cold starts, I noticed after removing one throttle body after a minute or so of trying to get it to run, it appears the fuel tends to "fall out" of suspension and try to puddle in the intake, if you rev it a bit, it seems to stay cleared out. And after there is a little heat in the motor, it cleans up and runs good. The road test was better than expected, I am very pleasantly surprised at how well it really does run!
 
It was running a old school 850 double pumper on a M1 single plane, and I had tuned that with a o2, and had it pretty sorted out, but I can say, somehow, it actually feels STRONGER, off idle all the way.... I think the 410 cubes must help deal with the plenum volume pretty well... I consider the project a COMPLETE SUCCESS
 
I bought a FITEch for my 360 build. That is awesome man. What alternator will you use to provide the power to the pump and dual fitechs? I spoke to them at PRI and they said they are very 12 volt min sensitive... good thread boss. I like it.
 
What amp alternator? Keep it up, looks cool. Can't wait to hear how you like your FiTech
 
Do you have data logging software? Can you show a graph or maybe tell us what it looks like?
 
Took the duster out today for its first cruise, but first I gotta say, it really doesn't like cold starts, I noticed after removing one throttle body after a minute or so of trying to get it to run, it appears the fuel tends to "fall out" of suspension and try to puddle in the intake, if you rev it a bit, it seems to stay cleared out. And after there is a little heat in the motor, it cleans up and runs good. The road test was better than expected, I am very pleasantly surprised at how well it really does run!

The puddling always concerns me with these manifolds. Otherwise, great news. Congratulations!
 
You can do so much with this FITech stuff. You maybe able to tune it so it doesn't puddle up. There is a helpful FITech group on Facebook. Good troubleshoot team there.
 
The puddling isn't something you can tune out, it happens because of the cold manifold... a few blips of the throttle while it's warming up, keeps it cleaned out, after there is a little heat in the motor, it doesn't do it anymore
 
Just a little update on this thing, been driving it pretty regularly for over a year, and man is it IMPRESSIVE. I've done basically ZERO tuning or fiddling with it, it's a tiny bit temperamental on dead cold starts, but other than that, it's get in and drive anywhere. There are absolutely no drivability issues at all. It makes gobs of torque right off idle, and traction on street radials is pretty non existent untill high gear...
 
Just a little update on this thing, been driving it pretty regularly for over a year, and man is it IMPRESSIVE. I've done basically ZERO tuning or fiddling with it, it's a tiny bit temperamental on dead cold starts, but other than that, it's get in and drive anywhere. There are absolutely no drivability issues at all. It makes gobs of torque right off idle, and traction on street radials is pretty non existent untill high gear...
How is top end pull...?
 
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