Cycling Valve???
#1
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I recently had some items installed on my 89 951... Cup car turbo, Tial 1bar wastegate, APE Stage II chips and a Turbonetics pop-off valve. With this setup, should the cycling valve be removed or otherwise modified? Or is it okay to leave it as is? Currently, it's still hooked up and the car runs great. I read that the cycling valve should be unhooked with the LR wastegate and am wondering if it's the same with the Tial... Thanks.
#2
Burning Brakes
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I installed a deltagate on my previous '87 951 with a 9 lbs. (or .625 bar) spring. I also removed the cycling valve and used a turbonetics MBC. If the cycling valve is still plumbed correctly it should be limiting boost to .2 bar at part throttle and then giving you the 1 bar at WOT. Do you still have the autothority banjo bolt installed? I'd remove it, get a calibrated boost gauge set the MBC to 15 or 16 psi and forget about it.
The reason I recommend using the MBC in conjunction with the 1 bar spring is so the wastgate will not creep open until it hits 1 bar, in other words it will stay shut and blow open right at 1 bar. With out the MBC it will gradually open and then dump everything over 1 bar. Another good thing about the MBC is you can dial in more boost then if you were only using the spring.
Hope that helps,
The reason I recommend using the MBC in conjunction with the 1 bar spring is so the wastgate will not creep open until it hits 1 bar, in other words it will stay shut and blow open right at 1 bar. With out the MBC it will gradually open and then dump everything over 1 bar. Another good thing about the MBC is you can dial in more boost then if you were only using the spring.
Hope that helps,
#3
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So your using this as a single port setup,,just relying on the 1 bar spring? The hose from the old wastegate is going to the top of your new wastegate? That hose is from the back of the cycling valve.
If so then you should leave the cycling valve hooked up. The two small hard lines that go under the manifold; you still have them hooked up the factory way: intercooler pipe/banjo bolt to the left one and the fitting/hose from the J boot to the right one?(small ones not large) then you should be ok. If you put in MBC as stated you would be better served after spending that amount of money.
Ski
If so then you should leave the cycling valve hooked up. The two small hard lines that go under the manifold; you still have them hooked up the factory way: intercooler pipe/banjo bolt to the left one and the fitting/hose from the J boot to the right one?(small ones not large) then you should be ok. If you put in MBC as stated you would be better served after spending that amount of money.
Ski
#4
Burning Brakes
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Ski, why do you recommend leaving the cycling valve hooked up?
Here is how I hooked mine up.
1. Plugged the hole in the intake boot.
2. Ran a silicon line from the banjo bolt to where the cycling valve originally was.
3. From there I used a 2 way tee one line went to the wastgate the other went through the firewall to the glove box where my MBC was mounted then from there it went back out to the wastgate.
The only reason you would possible want to keep it is if the computer senses a fault it can go into limp home mode and restrict boost to .2 bar. You have to choose between performance and factory safeguards. In my case I felt like I knew enough about what was going on under the hood to take the risk. Not that I think there is a major risk in doing this.
Regards,
Here is how I hooked mine up.
1. Plugged the hole in the intake boot.
2. Ran a silicon line from the banjo bolt to where the cycling valve originally was.
3. From there I used a 2 way tee one line went to the wastgate the other went through the firewall to the glove box where my MBC was mounted then from there it went back out to the wastgate.
The only reason you would possible want to keep it is if the computer senses a fault it can go into limp home mode and restrict boost to .2 bar. You have to choose between performance and factory safeguards. In my case I felt like I knew enough about what was going on under the hood to take the risk. Not that I think there is a major risk in doing this.
Regards,
#5
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Does anyone have any photos of a Deltagate installation on a 951? I just bought one from Huntley Racing, and would like to see some photos, so I can show them to whoever ends up welding the flanges one for me. Thanks in advance.
#6
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Stephen,,
remember I asked him what he did with the hose from the cycling valve,,hence the front hard lines that go under the intake manifold. If he is still utilizing those lines...he would have to plug or use the hose off the cycling valve.
I hooked mine up the same way you did,,banjo to top of LR wastegate, side port to vac side of wastegate. I grabbed my boost pressure from the vaccum lines off the fitting where the KLR gets its signal from at the intake manifold. I put my boost gauge in an A-pillar. But we have MBC and he stated nothing about having one.. therefore being a single port, then utilizing the cycling valve to feed the top of the wastegate.
Funny,,I put my MBC in the glovebox too,,LOL.
I thought out of sight out of mind and playful hand!
remember I asked him what he did with the hose from the cycling valve,,hence the front hard lines that go under the intake manifold. If he is still utilizing those lines...he would have to plug or use the hose off the cycling valve.
I hooked mine up the same way you did,,banjo to top of LR wastegate, side port to vac side of wastegate. I grabbed my boost pressure from the vaccum lines off the fitting where the KLR gets its signal from at the intake manifold. I put my boost gauge in an A-pillar. But we have MBC and he stated nothing about having one.. therefore being a single port, then utilizing the cycling valve to feed the top of the wastegate.
Funny,,I put my MBC in the glovebox too,,LOL.
I thought out of sight out of mind and playful hand!
#7
Burning Brakes
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Ian, I used these pics http://www.tonygarcia.org/wastegate.htm I had to take it to 3 different places before I could find someone who had the brains to install it. Make sure they angle it up a tad. Mine hung down kind low. I had to re-clock it after it was installed because the vacuum port on the side was hanging down to low, which caused a few brass fittings to get scraped off. Christopher White on the 944 List also has some pictures of his install. He had his pointed up like the factory wastegate.