I've done some searching around and found only one person who has publicly done the Variable Intake Manifold swap to a VE-Automatic. It appears as though it wouldn't be that hard, and quite possibly be worth while... especially when my car has a 5-speed. Just wondering if anyone else besides Aaron92se has done this, and what kind of labor/part swapping is involved.

 

Not sure but here goes...

VE5 intake
vacuum selonoid
vacuum hoses
assuming the ve auto already has the plug harness for the selonoid?
not sure if the auto ecu is set up to control the selonoid valve?
of course gaskets-n-such..


?

 

Yeah, not sure how the ECU would come into play. And apparently Aaron found a workaround for the vacuum solenoid harness if the VE-Auto's don't have them... although I'd think they would.

The RPM switch runs about $40 and should do the trick... guess I'm just awaiting Aaron's input. And possibly a write-up!? (though doubtful)

in the meantime...

 

the auto ECU doesnt have the control for it. I looked into it a while back (before Aaron actually) and the wire isnt even on the ECU harness but I stuck my probe in there and got no reading so you would need a 5spd ecu for it to work like the factory.

 

Yeah, the auto ecu has the VI disabled via hardware (missing a resistor to connect the transistor to the ecu pin) and disabled in the software (auto ecu has the "off" setting at 500 rpms so it never comes on).

This can be changed but window switches are cheaper. (although the ecu uses rpm and load to determine switching).

The ecu switch off point is 3400 rpms. Any point below that and more than about 3/4 throttle and the solenoid should be on.

 

I wonder could one hook it into the same circuit that runs the VTC and use that circuit as the trigger for the VI as well.

 

well they are on the same power circuit (its the grounding that controls them). I found this out when I put my motor in this last car and realized the VI didnt work on the manifold. I got to looking and found a blown fuse. Well in my looking in the FSM that same power wire runs to the VTCs. My guess is the guy that owned it before me tried to ground the VTCs but grounded the hot wire instead and blew that fuse.

 

they are both load and rpm based, the question is how close the maps are

 

I had an accord which had the same function on an intake manifold. The difference being it wasnt just restricted to manual cars only so you could change the intake manifold and just get the corresponding ECU(auto/manual) Before i got the ECU i hooked the hose that goes to the diaphram that opened the variable intake to a vaccum source on the intake that opened up at abput 3500 rpm. Is that something that might be a possibility on the 3rd gens. You guys get what im talkin about? dont know if i made it clear enough.

 

If you have a 5spd swap already done to your VE, then just get a 5spd ECU. That is the easiest sure-fire way to get you up and running. I'm sure you can get your hands on a VE 5spd ECU cheaper than an RPM switch.

I used the Summit Racing RPM Switch to get my VI working. I have been doing a lot of dyno testing with the VI on and off and can't see the slightest difference. This can mean only two things, my setup isn't working properly or the VI doesn't help at all. I am going to physically zip tie the VI open or closed and then do my before and after dyno runs to see if there is any change in the torque curve. I've been too busy with these spacers to mess around with making my car faster.

 

I have the 5 speed VI FS with the solenoid pm me if your interested.

I can see if there are any VE-5s at the jy here for an ecu.

Aaron, can you try disconnecting the vaccume? My power valve has a siezed solenoid maybe yours is as well. I need to shoot some carb cleaner in it.

~Alex

 

My solenoid is great and the VI is functional when I rev the motor. But, I can't say for sure what it's doing when I'm under load. So to be absolutely sure, I will just zip tie the power valve in place and do my dynos.

 

If you find a VE5 at the JY, I need some stuff. PM me and I'll go down...

 

Im actually in columbus again permanently I need to change my profile again. Ask colombianmax hes in chicago.

Aaron- do you have a one way valve and vac canister? I don't think the canister is 100% needed but I know the valve is. At WOT/high rpm there probably isn't enough vaccume to hold it open.

~Alex

 

If you are not going to use the ECU to control the VI, then you should simply modify the intake manifold to match your target powerband (low end torque, high end power).

I made a thread about it a couple years ago, but essentially due to the characteristics of the intake design and how the VI functions on these cars, controlling them any other way is inefficient.

 

your last statement is exactly why the canister is needed. It holds the vacuum in reserve so it can be used when vacuum is limited.

I put such a big cam in my Chevelle one time I had to get a vacuum canister for my power brakes.

 

next time go electric Vacuum pump

 

Yeah, I have everything setup just like the VE 5spd. It definitely works. I'm just not 100% sure it's working at WOT since the dyno results were exactly the same between ON and OFF.

 

do you know how long ago this was? I dont think they had them back then and if they did I couldn't afford them. We are talking back in 1992 or so.

 

they were factory equipment on the 80s full size wagons

 

IMHO if you are using this VI w/ the rpm switch, here is my thoughts.

VI = small area for low end and big area for high end.

auto version = big area for high end

So on a dyno, when maxing out, there should be no big diff in the high end. I imagine by the time you floor it, the VI is probably open.

 

Yeah. I have trouble dyno'ing below 3500 rpm. I can't dyno in 1st gear b/c I have traction issues and my torque converter flashes to 3K. So I lock my torque converter and do my dyno run starting at 3K - 3.5K. I haven't wired it in so I can keep 2nd gear from kicking down yet. But I thought the stock VE 5spd VI kicks in around 4500. I remember Shawn did this years ago, but forgot when his LED showed the release point.

But once I make sure the VI is closed before and open after, then I will be able to accurately find the optimal VI release point by overlapping the torque curves. But right now, they are identical, which means, the optimal release point is below 3500 for the VE Auto, the VI doesn't help on the auto, or my stuff simply doesn't work.

 

The VI closes below 3400rpms and at more than about 3/4 throttle. Less than 3/4 thottle or above 3400rpms, its always open.

 

And they are not hydraboosters so they are not worth talking about, especially in this thread.

Essentially, but the depending on the TPS, engine load and speed, it's kinda quirky

 

hydro boosters are very different animals than what we were discussing