nerx

Have been getting a solid 12 of boost and spiking to about 13 lately. So with my mods only being the air box mod and a downpipe, I thought it might be a good idea to turn down the boost a bit. I decided to attempt the Home Depot boost controller from Rob Robinette's site and it wasn't too bad to install. Now the testing part. Drove the car around for about 15 minutes to warm it up and then I found an open stretch of road where I gave it some gas in third gear with the valve completely open. Got to about half throttle and saw my boost jump straight to 15! Let off immediately. Played around with it a bit in different gears, and the most I can give it gas is about half throttle before letting off. I got to tell ya, seat of the pants meter seems way up. Anyways, going to go buy a larger valve tomorrow, probably 3/8" or so, and I hope that helps. Anyone else have this problem? Any other ideas I can do. Don't really want to go through the pain of running bigger vacuum lines again. Any suggestions would be appreciated. TIA

Justin

JONSKI

How many turns did you open the vavles initially? I think the Robinette site recommends two full turns.

Benjamin

I've had them for 8 months with no problems. Granted, each valve is SLIGHTLY different in terms of construction, but you should be able to set it. Mine runs a perfect 12-10-12 pattern. They do tend to turn a bit if their movement is restricted within the engine bay. It's entirely possible that it got bumped, and turned it just enough to give you that spike--once it's set around 12, 15 is not that far away.

-BN

Wargasm

I doubt you need bigger valves...

I ran 1/4 inch home depot valves for a long time with excellent results. I started wtih the valves ALL THE WAY open and gently prodded the gas to test responses before going wide open.

Keep turning the primary turbo one closed by about 1/2 turn in the beginning and then 1/4 turns when you start finding the sweet spot. The sweet spot where you will get the proper boost is very small so I think you're just not testing it enough.

I think the Rob Robinette instructions say to do the switchover spike valve only after you have the primary working right don't they?

Anyhow, my advice it to keep playing with it starting from both wide open. If you see around 7 psi when it's wide open, then that is telling you that the lines and valves are plenty big.

Brian

mjw

iTrader: (1)

What year is your car? If it is a 93 did you remove the pills in the lines? If a 94-95 you have to enlarge the inlet port on the wastegate actuator for the controllers to work..

nerx

Mine is a 93. The thing I am thinking about is that the vacuum hose that I ran is only 1/4". Also I didn't do the secondary valve yet; I was planning on doing that this weekend. But that shouldn't really be a problem if I'm having high boost on the primary; I thought it was too control secondary pre-spool so that spikes would be avoided at the switchover. Also, I know the valve was COMPLETEY open and was not bumped because I mounted it in my ashtray for easy adjustment. I did not do anything with any pills, but I don't think I have to worry about them. What I did was since the valve used 1/4" (I think Robinette's site showed connecting 6mm vacuum line to a 1/4" copper pipe about 1.5" long extruding from the valve. ) I used some 1/4" vacuum line I had laying around from both ends of the valve to my turbos. I then connecting two 6" pieces of 9/32" vacuum line I found to the two ends of the 1/4" hard line so that I may connect the other end of the 9/32" line straight to the nipple of the wastegate and turbo, therefore eliminating the original vacuum line that was there, so that any pills that would of been in that line are now not an issue. Do you think I just need to run a bigger line to the valve?

skunks

i get 10psi all the way to redline with my homedepot boost controlers. when you test it out, you did open them all the way up and then slowly closed them right?

nerx

Yep, I haven't even tried closing it at all yet. ALL THE WAY OPEN = 15 psi at half throttle.

skunks

have you tried just an open vaccum hose?

adam c

iTrader: (2)

I have been running both valves for several months. Getting them adjusted right is not a quick process. I reccommend that you mount the valves in the engine compartment. It may be that part of your problem is from the long vacuum lines required to do an inside mount. Don't even think about installing a prespool controller until you have the boost controller working right.

1/4 inch hose should be fine.

Adam

RonKMiller

Agreed. The long vacuum line is going to make it VERY difficult if not impossible to adjust.

There is a vernier cable operated manual boost controller which allows it to be adjusted from the inside yet still mounted in the engine compartment.

Also, when you mount the valve try to make sure it is in an area of relatively stable operating temperature and use a relatively thick walled hose for your connections.

nmo93

i had the hd boost controller too for a while and had no problems like that. but i adjusted mine differently, the way robinette's site says. his site states to start w/ the valve closed, then open it two full turns. this gave him 8 lbs of boost, then by closing the valve the pressure increased. try this method. if it doesn't work, try turning the valve around. i thought that these needle valves worked one way? correct me if i am wrong. but anyway, look at his site again and re-read what he wrote:
http://www.rx7turboturbo.com/robrobi...controller.htm
nick

apneablue

Sounds to me like those long lines may be causeing a bit of probs...I have both and they were qute a biatch to adjust at first. getting 11-9-11. Plus make sure that the hose is not kinked at all or that will throw it off too....after mounting it in the engine bay and testing again, if it doesn't work then I would change to a different 1/4" valve...

Good luck

flunkysama

iTrader: (4)

If you bought your car used, consider the possibility that a previous owner put newer turbos with built in restrictors on the car. I'm not sure how to check, but if the original hose running to the wastegate actuator does not have a brass flow restrictor (i.e. pill) in it, you probably have newer turbos.

Also, just get out your hand pressure pump and verify that wastegate actuator is working and you don't have dirt or something clogging your new lines.

mjw

iTrader: (1)

I agree with the posts above, it is most likely due to the length of the line into the cabin. Mount the controllers in the engine bay near the fan relays and shorten the llines up. I would then start with the controller all the way open, that way you are as safe as possible and can adjust up from there.. do the prespool line too while you are there and fine tune that transition. Good luck!

Matt

adam c

iTrader: (2)

The needle valves are not one way valves. Turning them around will not change anything. It is a valve that works like a vice.

Adam

nerx

Ok here's what I've decided: First I think the long lines might be causing some problems, although Brian Dowling's site states he uses it in his ashtray and it works fine. Also the line I used might be a little too restrictive; It is a 1/4" but he ID of the line is only like .17" So sometime today I'm going to relocate the line to the engine compartment and run nothing but 9/32" vacuum line. I'm also going to go ahead and put the prespool controller on also. I'm thinking of possibly macking some sort of bracket out of aluminum that will be bolted in the engine compartment that I may zip tie the valves onto so that they do not move. I'll hopefully do this sometime today and write back what I decide to do and if it worked. Thanks for all the help!

Justin

adam c

iTrader: (2)

I used 1/4 inch (inside diameter) fuel line. It is heavier than standard vacuum line, and will fit perfectly on both nipples. I really recommend against putting in the prespool valve. Do the boost controller first. It may be that you will have a smooth boost pattern without needing the pre spool valve. The pre spool valve really complicates the adjustment process.

If you don't like your boost pattern after getting the boost controller adjusted, then intstall the pre spool valve.

nerx

Thanks Adam C. I'm going to run a bigger line to the valve re-located in the engine bay. I'm going to hold off on the prespool controller for now. Thanks for the advice.

Justin

adam c

iTrader: (2)

Good luck

nerx

Well, I switched the vacuum line to 1/4" ID fuel line and ran it to the valve now located in the engine compartment. Had to turn the valve 3.5 COMPLETE turns open, but finally am getting around 10-11 pounds of boost. Still needs a little tweaking though. I'm still hitting like 13 though in third gear. I also noticed that when my secondary turbo comes online, I get a spike of about a pound or so, then it immediately drops off to around 7, sometimes 8 and remains there until redline. Shouldn't I be getting about 10 pounds till redline? Let me know your thoughts/comments. Thanks all.

Justin

skunks

well yes and no, getting 10psi all the way to redline is sometimes possible but most of the time, the boost will drop to 8-9psi after 6-7krpm (in the upper RPMS).

did you do the precontroller yet? if your having too much trouble, try the non-seq on dontbearikki.com site, its totally reversible if you dont like it and is pretty darn easy.

good luck and congrads on getting that boost down

nerx

No, i haven't gone non sequential yet. I want to but with my only mods being DP and intake, I'm worried about too much lag. I was hoping to do it in the next few months when I get a catback on. What do you think? Should I give it a shot now?

adam c

iTrader: (2)

Sounds like you are getting things under control. I would play with the boost controller a little longer. Try some different adjustments. Fine tune it a little. At least you have it working, good job.

Adam

skunks

i would get a MP while your at it in anycase, the non-seq conversion is pretty easy to do (only about 7 vaccum lines you gotta reroute/mod/plug and one thing you gotta wire open which is easily accesible from under the car.)

BTW: DO NOT, I repeat DO NOT rip out any solonoids!!! Follow the dontbearikki site since he got nice pics which show exactly where the things are. If you need zoomed out pics of where to find these things (the only real problem with his site is he only has close up pics, well kinda), just ask and I'm sure me or another guy on this forum would be more then happy to take some pics for you and point out where stuff is.

IF you do decide to mess with the precontroler line, becareful, I hear a tiny adjustment makes a huge difference.

good luck