Boost Creep / Spike up to 30lbs! Also, not making more power past 21lbs
#1
www.mancavecolorado.com
Thread Starter
Boost Creep / Spike up to 30lbs! Also, not making more power past 21lbs
We have tuned my FD to about 21.5 lbs until it seemed like it wasn't making any more power raising the boost. We kept the timing pretty conservative at about 12 degrees advanced since many say advancing the timing doesn't make a huge difference in power. I have a GT35/40 kit from A-spec tuning so I would think the turbo would be efficient to much higher.....I have plenty of fuel with duel RP pumps, 850primaries and 1600 secondaries. I do have stock ign setup and only runing 9's all the way around which seem to fowl very quickly! Any idea's?
Second part of question....is my boost is either creeping or spiking up to 30lbs! I really haven't stayed in it for long enough to see if its just a spike but it seems like it wants to hold there. I have a Tial 44mm Wastegate so it would seem that should be big enough. What could my issue be? We will be messing with it on the dyno tomorrow and would like to get some ideas in case we can't figure it out on our own.
Thanks again for any help as I'm not getting anywhere searching the forum
Second part of question....is my boost is either creeping or spiking up to 30lbs! I really haven't stayed in it for long enough to see if its just a spike but it seems like it wants to hold there. I have a Tial 44mm Wastegate so it would seem that should be big enough. What could my issue be? We will be messing with it on the dyno tomorrow and would like to get some ideas in case we can't figure it out on our own.
Thanks again for any help as I'm not getting anywhere searching the forum
#2
BDC Motorsports
One thing to keep in mind, Mikey -- you're at 5200-5400ft elevation, so the turbocharger is having to work a percentage more to try and make up for the lack of ambient atmosphere. Then, on top of that, it's also working harder to try and make/sustain manifold pressure -- at a mile up vs. sea level, it's having to spin a hell of alot faster. This will make it overall less efficient than the figures that you'll see others post. It doesn't surprise me that it's doing this quite honestly.
B
B
#3
www.mancavecolorado.com
Thread Starter
I can deal with having to buy a new turbo at some point if that's the case.......but what about it going up to 30lbs? It was spiking to 25 and dropping down to 21.5, but now every time its shooting way up? Could I have blown a vacume cap or something? Is my wastegate to small?
I have already disconnected the Blitz SBC-ID boost controller and tried the Turbo XS manual but that didn't seem to help. Got to go to bed now....hopefully some people will have some magical answers for me so tomorrow goes good!
I have already disconnected the Blitz SBC-ID boost controller and tried the Turbo XS manual but that didn't seem to help. Got to go to bed now....hopefully some people will have some magical answers for me so tomorrow goes good!
Trending Topics
#8
www.mancavecolorado.com
Thread Starter
The wastegate spring is Green which from what I remember is 12lbs. So what exactly happens if the wg is too small? Do I need to port it or just buy a bigger wg? It seems like a 44mm is pretty damn big.
#10
Crash Auto?Fix Auto.
iTrader: (3)
Spiking? I'd check the wastegate signal lines with a fine tooth comb. Make sure there's no blockage in the lines, no leaks/cracks etc. Then I'd move onto other options.
If you find no problems with the signal lines, pull the lines off the wastegate compeltely and go for a drive. The car should boost to spring pressure - no more. If you creep well above the 12psi range, then you know its a setup problem. Ie. poor manifold design (BTW, what kind of mani.?) timing too retarded (12 degrees shouldn't cause any issues though IMHO) or wastegate being physically too small (is this a bridgeport?)
If you find no problems with the signal lines, pull the lines off the wastegate compeltely and go for a drive. The car should boost to spring pressure - no more. If you creep well above the 12psi range, then you know its a setup problem. Ie. poor manifold design (BTW, what kind of mani.?) timing too retarded (12 degrees shouldn't cause any issues though IMHO) or wastegate being physically too small (is this a bridgeport?)
#12
Rotary Enthusiast
Join Date: Jun 2003
Location: Ottawa, Canada
Posts: 874
Likes: 0
Received 0 Likes
on
0 Posts
Not sure about the exact specs of your turbo(since it's an A-spec kit), but if its just a regular GT3582 compressor it's not going to make much more boost than that on a rotary. (based on the compressor map) You'll need a bigger turbo to sustain the higher boost levels to redline, efficiently.
#13
"Elusive, not deceptive!”
[QUOTE=MichaelB145;7335707 I do have stock ign setup and only runing 9's all the way around which seem to fowl very quickly! Any idea's?
[/QUOTE]
If you are boosting to 20 PSI you need an ignition amplifier. Something like a HKS Twin Power.
Barry
[/QUOTE]
If you are boosting to 20 PSI you need an ignition amplifier. Something like a HKS Twin Power.
Barry
#14
Need more sleep
iTrader: (1)
Might consider using a higher pressure wg spring to address boost control, running boost closer to spring pressure seems to help, issue seems to come up when you start upping boost to 2x spring pressure or higher.
Maybe that turbo is starting to give too high a backpressure to make more power when you tun up the boost.
#15
Senior Member
Shoot, even a tiny wastegate should hold 21.5 psi. Something is wrong with your boost controller source, function or wastegate not opening. It takes a huge wastegate to hold 10 psi.
Make sure you have it coming from the plenum and not one of those ports that draw from pre TB lOl.
BTW I'm at 3200ft. the correction is less than 1 psi.......
Make sure you have it coming from the plenum and not one of those ports that draw from pre TB lOl.
BTW I'm at 3200ft. the correction is less than 1 psi.......
#17
BDC Motorsports
Shoot, even a tiny wastegate should hold 21.5 psi. Something is wrong with your boost controller source, function or wastegate not opening. It takes a huge wastegate to hold 10 psi.
Make sure you have it coming from the plenum and not one of those ports that draw from pre TB lOl.
BTW I'm at 3200ft. the correction is less than 1 psi.......
Make sure you have it coming from the plenum and not one of those ports that draw from pre TB lOl.
BTW I'm at 3200ft. the correction is less than 1 psi.......
B
#18
Stay tuned...
iTrader: (3)
Join Date: Jul 1997
Location: West Islip, Long Island NY
Posts: 2,917
Likes: 0
Received 1 Like
on
1 Post
I had the same issue, it was the wastegate spring. I changed my 10lb spring to a 20lb spring and since then easily hold 30psi with no issues.
As far as not making anymore power, not sure about the turbo but check for boost leaks maybe?
Anthony
As far as not making anymore power, not sure about the turbo but check for boost leaks maybe?
Anthony
Last edited by AnthonyNYC; 09-16-07 at 12:40 PM.
#19
7s before paint!!!
iTrader: (2)
You might pressurize either side of the diaphragm and make sure it is still in tact. I recently had a boost control issue. Running just off the spring it worked perfectly but as soon as you tried to use some kind of boost control it became erratic. The diaphragm was blown off the piston, when you would apply pressure to the bottom it would seal and open the gate. But when you applied pressure to the top it would push the diaphragm away from the piston and start to leak. My situation was even more complex because i was running dual 44s and only one of them would work causing exhaust to be vented from only one rotor.
Good luck.
Good luck.
#21
www.mancavecolorado.com
Thread Starter
I don't get it..... Now its not going up to 30lbs anymore and I haven't changed anything! I am having problems with it breaking up so it looks like I'm going to upgrade the ingition system first and then see what happens! Thanks for all your input, but now I don't know how to fix something that isn't broken.
#22
In the burnout box...
iTrader: (32)
You might pressurize either side of the diaphragm and make sure it is still in tact. I recently had a boost control issue. Running just off the spring it worked perfectly but as soon as you tried to use some kind of boost control it became erratic. The diaphragm was blown off the piston, when you would apply pressure to the bottom it would seal and open the gate. But when you applied pressure to the top it would push the diaphragm away from the piston and start to leak. My situation was even more complex because i was running dual 44s and only one of them would work causing exhaust to be vented from only one rotor.
Good luck.
Good luck.
Thread
Thread Starter
Forum
Replies
Last Post