Recently I put my complete RB set up on my 91

At first I did not take the ACV and airpump out and left them in there. Well I had waterpump melt down and so I had to replace everything but instead of reinstalling the airpump and acv, I just blocked them off.

Here's the thing, my RB set up came with that block off plate specifically for shelving the ACV.

Alright that's fine and all, except now that the air pump and ACV are gone I connot get to 9K very well at all. It caps off at about 7 or so.

My main question for asking this is:

When you block off the ACV is it only wise to do this when you have an aftermarket air intake set up like a K&N filter or something?

I have the stock airbox still on there and so maybe, I was thinking, that the block off plate is supplied for setups with K&N filters etc....But you leave the ACV/Airpump on when you have the stock air?

 

I'm pretty sure the 5/6th ports as well as the VDI system use air pump pressure to operate on the series 5 cars. That might explain in part your lack of top end, if you have an N/A car (disregard if you have TII).

Either way, a blocked off ACV should not reduce engine performance at all.

 

Why do you want to go to 9k?

 

yeah that's kind of what I thought too. But I remember a long while back when I was trying to order a K&N filter for my 86 that the person I was ordering it from said that the setup would eliminate the need for an airpump.

I think I'll go order one for my s5 now.....i have this sneaking suspicion that this has something to do with it.

Whatever. I need a new air kit anyhow.

 

You would still need the airpump if you had a cat. Getting a new filter doesnt justify having no airpump. Not having cats (straight through exhaust) is the reason to get rid of the airpump.

 

Why would I want to go to 7?

 

Dittos to the above. Buy a FSM or download the ones available on the web for free.

 

You need to reinstall the air pump and ACV if you want your power back. Pressure to operate the actuators comes from the air pump, and is routed via the ACV. This is why you should research mods before ripping stuff out...

 

whoa there buddy.

Look, I didn't just decide to rip out because I thought It was gonna be a cool mod.

Actually I was just going to leave all that stuff in there.

But because I was lazy, I didn't take the whole five minutes it takes to reinstall the airpump after redoing my waterpump.

Rather I figurered that it would be better to block off the ACV with the plate they gave me so that I could spend a couple of hours scratching my head. So there!

I don't have airpump on my 86.....Runs just fine.
Since I don't have a CAT on my 91 either, I followed the same logic.

Drrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr.

After thinking about it last night 60 times, in five minute increments, I came to the conclusion that the VDI and 5&6 ports are a completely different set up from the 86-88 port actuation. And no new airbox is gonna work either.

 

You are completely correct. The S4 uses exhaust backpressure, the S5 uses air pump pressure (via the ACV).

I'm not ragging on you, just pointing out that a little prior research can often avoid problems like this. At the very least grab the S5 FSM and read about the stuff you plan to modify or remove. This is one of those topics that's been done to death here too, so there's plenty of info available if you need it.

 

http://www.teamfc3s.org/forum/showth...port+actuators

 

Remove the air pump and run an electronic actuator with a rpm sensor =)

 

Put the airpump back on along with the acv. There is no discernable loss of power with them on. Neither the airpump nor the acv will get in your way when working on the engine or driving the car.

 

Put them back in???

whoa whoa whoa.

That's almost as crazy as NZ's suggestion to read up on a proceedure before doing it.....

That could take well over 10, maybe even 20 minutes!

You guys are loco, essay...................That's crazy talk, crazy!