Looking for more 3900 performance

[Fieroghini]

Tried it. Doesn't work.

[ForcedFirebird]

Have you read Joseph's thread here? He shows a video and explains how he did it.

[Fieroghini]

yes I read it. It physically works. I can retard it at anytime. I had it locked retarded and it wouldn't even start. I put it to stock and it fired right up. Once running I energized the phaser and it stalled out. I revved it up to 3500 and energized it and it lost rpm's. I told the dyno tuner that it may only work above 5000rpm's. He energized it at full throttle at 4500 and it still lost power. Josephs cam is a regrind and he also had it retarded and chose to put it back to stock. I'm sure there is a setting to give improved power but it's not either of the two extremes and that's as far as I'm going with it.

[CNCguy]

Did you use anything to limit cam travel? I don't have the numbers in front of me but I measured the VVT travel on a CMM. The travels were something like +30 degrees and -24 degrees from straight up. IMO 54 degrees is too much for our needs. When I do another LZ engine, I plan to limit the cam timing to +10 and - 10 degrees from straight up.

Wiring for the IMT is pretty simple. By grounding "C" the Fan closes, removing the ground opens it back up.

Edit: "D" is just an output to the ECM to verify that it has closed

[Fieroghini]

No, I didn't do anything to limit travel. I'll play with the intake and see if I can get it going.

[IsaacHayes]

Grab one from a 3500 VVT motor, they are a non variable intake.

EDIT: Doh! a bit late to reply, had the window open from the other day.

...
It's possible taking the vane out of the intake is causing poor power all over. Doesn't it close off the long runners and open the short up when open? So with it gone, you have a path through both the short and long, thus creating "no runners" almost in effect since there is two paths to the cylinder heads... Killing all velocity. What happens if you leave the door in? But if you don't want to mess with making it work, get the 3500 VVT upper intake. But I'm betting that your intake is causing problems with that vane out...

[Fieroghini]

I'm going to put it back in today and see if it'll hold speed better at 55mph. If it does I'll get it functioning. If not I'll look more into the 3500 intake

[Fieroghini]

I ordered my timing set from monsterpartsonline.com. $117 with shipping. Unfortunately I had to go to the dealer for the intake connector. $89. I should get it tomorrow and I'll just use the wiring for the cam phaser to run the intake instead, so it shouldn't take too long to get working.

[Fieroghini]

I got the wiring harness today and tested it out. It wasn't quite so simple. Either the power or ground must be switched and then another switch to ground to actuate the valve. If I tried to ground them together it would not work. If i left both grounds grounded and switched power it would not work. It doesn't matter too much because in my screwing around I managed to short out the actuator. What's another hundred wasted? Back to the drawing board I guess.

[CNCguy]

I connected "A" to 12vt and "B" to ground. Whenever "C" was connected to ground, the IMT fan would open. When "C" was removed from ground the fan would close.

The LZ4 intake without IMT fits with no problems. I picked up an LZ4 intake and would like to dyno with both to see how much difference the IMT really makes.

[Fieroghini]

That's how I had it working also. It would just need a switched power to not kill the battery and a time delay to energize the valve because it doesn't seem to work if I gave grounds at the same time. Have you dyno'd a stock 3900 yet? If so what numbers did you get and what transmission did you use?

[CNCguy]

Strange that your IMT operates differently but who knows. Mine is wired to power on when the key is turned on.

My 3900 has not been dyno'd yet as I have not finished my swap. Still need to finish up the wiring, exhaust and tune it. The engine has a 260 duration/.563 lift cam, Comp Cam springs/retainers/locks, pre '99 timing chain set, 1 5/8" shorty headers, 75mm throttle body that has been bored straight through, a new Ford T-5 transmission and is mounted in a '79 MGB. If I could just get some time to finish it up, I would be happy.

[Fieroghini]

Sounds like it works the same, there is just a sequence to it. Looks like you have a pretty healthy setup. Are you worried about lifters at all?

[CNCguy]

Mine toggles positions by grounding/ungrounding "C". No other wires have to be disconnected.

Not worried about the lifters but if there is a problem, I will try the LS lifter spring upgrade on them. I plan to upgrade to a larger cam in the future after I get the tuning right on this combo.