T78 Rebuild-Update
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Joined: Mar 2001
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From: Florida
Badog,
Yes, sure am. That was sort of thrown on there so I could drive it around :-) Because it sits so high, I'm going to have the end cut off the compressor housing and have a bend welded in there. This will give me an additional 2" or so of clearance and I won't have elbows blowing off! If there's a cast elbow out there that'll work, let me know.
I've been tuning off and on for the past two days. I finally got it to the point where she isn't missing at higher rpm due to excessive fuel. My main problem now is that I can't produce significant boost. I'm not sure if I have the WG and boost controller hooked up wrong or what. Here's how it's hooked up:
WG side port to positive pressure (I have one nipple on the compressor discharge pipe)
AVC-R "NO" port to positive pressure (teed into same line as above)
AVC-R "COM" setting to the top of the wastegate
The screw adjuster on the top of the wastegate is all the way out. I've been told that the T78 kit comes with either a 15lb. or a 7lb. spring. I'm not sure which it is. All I know is that 1 measly psi by 4Krpm is NOT right :-( The AVC-R doesn't seem to be doing anything even though it's adjusted out to 1.1Kg/cm2. Theoretically, the AVC-R should be able to control boost, and raise it above spring pressure, even if the adjustment on the WG is backed all the way out, no?
Any ideas?
Michel
Yes, sure am. That was sort of thrown on there so I could drive it around :-) Because it sits so high, I'm going to have the end cut off the compressor housing and have a bend welded in there. This will give me an additional 2" or so of clearance and I won't have elbows blowing off! If there's a cast elbow out there that'll work, let me know.
I've been tuning off and on for the past two days. I finally got it to the point where she isn't missing at higher rpm due to excessive fuel. My main problem now is that I can't produce significant boost. I'm not sure if I have the WG and boost controller hooked up wrong or what. Here's how it's hooked up:
WG side port to positive pressure (I have one nipple on the compressor discharge pipe)
AVC-R "NO" port to positive pressure (teed into same line as above)
AVC-R "COM" setting to the top of the wastegate
The screw adjuster on the top of the wastegate is all the way out. I've been told that the T78 kit comes with either a 15lb. or a 7lb. spring. I'm not sure which it is. All I know is that 1 measly psi by 4Krpm is NOT right :-( The AVC-R doesn't seem to be doing anything even though it's adjusted out to 1.1Kg/cm2. Theoretically, the AVC-R should be able to control boost, and raise it above spring pressure, even if the adjustment on the WG is backed all the way out, no?
Any ideas?
Michel
Banned. I got OWNED!!!
Joined: Mar 2001
Posts: 1,008
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From: Bannished
Inline, in BOLD
Originally posted by rx7tt95
Badog,
Yes, sure am. That was sort of thrown on there so I could drive it around :-) Because it sits so high, I'm going to have the end cut off the compressor housing and have a bend welded in there. This will give me an additional 2" or so of clearance and I won't have elbows blowing off! If there's a cast elbow out there that'll work, let me know.
Greddy makes one...the kit came with one...orginally
I've been tuning off and on for the past two days. I finally got it to the point where she isn't missing at higher rpm due to excessive fuel. My main problem now is that I can't produce significant boost. I'm not sure if I have the WG and boost controller hooked up wrong or what. Here's how it's hooked up:
WG side port to positive pressure (I have one nipple on the compressor discharge pipe)
AVC-R "NO" port to positive pressure (teed into same line as above)
AVC-R "COM" setting to the top of the wastegate
I think better in pictures, reply to my last email with pics! If you can get them. Or heck, post them for the smarter people to see!
The screw adjuster on the top of the wastegate is all the way out. I've been told that the T78 kit comes with either a 15lb. or a 7lb. spring. I'm not sure which it is. All I know is that 1 measly psi by 4Krpm is NOT right :-( The AVC-R doesn't seem to be doing anything even though it's adjusted out to 1.1Kg/cm2. Theoretically, the AVC-R should be able to control boost, and raise it above spring pressure, even if the adjustment on the WG is backed all the way out, no?
I suggest, to figure out WHAT the wastegate is doing, take the AVC-R out of the equation. At least just unhook the lines going to the WG, keep the rest hooked up so you can monitor. One line would goto pressure and the other to? Maybe someone can jump in here
Any ideas?
Michel
Badog,
Yes, sure am. That was sort of thrown on there so I could drive it around :-) Because it sits so high, I'm going to have the end cut off the compressor housing and have a bend welded in there. This will give me an additional 2" or so of clearance and I won't have elbows blowing off! If there's a cast elbow out there that'll work, let me know.
Greddy makes one...the kit came with one...orginally
I've been tuning off and on for the past two days. I finally got it to the point where she isn't missing at higher rpm due to excessive fuel. My main problem now is that I can't produce significant boost. I'm not sure if I have the WG and boost controller hooked up wrong or what. Here's how it's hooked up:
WG side port to positive pressure (I have one nipple on the compressor discharge pipe)
AVC-R "NO" port to positive pressure (teed into same line as above)
AVC-R "COM" setting to the top of the wastegate
I think better in pictures, reply to my last email with pics! If you can get them. Or heck, post them for the smarter people to see!
The screw adjuster on the top of the wastegate is all the way out. I've been told that the T78 kit comes with either a 15lb. or a 7lb. spring. I'm not sure which it is. All I know is that 1 measly psi by 4Krpm is NOT right :-( The AVC-R doesn't seem to be doing anything even though it's adjusted out to 1.1Kg/cm2. Theoretically, the AVC-R should be able to control boost, and raise it above spring pressure, even if the adjustment on the WG is backed all the way out, no?
I suggest, to figure out WHAT the wastegate is doing, take the AVC-R out of the equation. At least just unhook the lines going to the WG, keep the rest hooked up so you can monitor. One line would goto pressure and the other to? Maybe someone can jump in here
Any ideas?
Michel
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From: Florida
Ok, answered my own question. The AVCR solenoid has three "ports" coming out of it. Two, at any given time, are used and the third is left open. For the sequential system, you're using the NO and COM ports. But when you go to an external wastegate, the NO nipple is screwed out and put in the NC port. COM stays the same. As configured, the two nipples will be at a 90 degree angle with the stock setup. With an external WG, they'll be in a straight line. Check Badog's topic/info request on this. https://www.rx7club.com/forum/showth...hreadid=127983 I posted apexi's diagram there.
Michel
Michel
Banned. I got OWNED!!!
Joined: Mar 2001
Posts: 1,008
Likes: 0
From: Bannished
Originally posted by rx7tt95
Ok, answered my own question. The AVCR solenoid has three "ports" coming out of it. Two, at any given time, are used and the third is left open. For the sequential system, you're using the NO and COM ports. But when you go to an external wastegate, the NO nipple is screwed out and put in the NC port. COM stays the same. As configured, the two nipples will be at a 90 degree angle with the stock setup. With an external WG, they'll be in a straight line. Check Badog's topic/info request on this. https://www.rx7club.com/forum/showth...hreadid=127983 I posted apexi's diagram there.
Michel
Ok, answered my own question. The AVCR solenoid has three "ports" coming out of it. Two, at any given time, are used and the third is left open. For the sequential system, you're using the NO and COM ports. But when you go to an external wastegate, the NO nipple is screwed out and put in the NC port. COM stays the same. As configured, the two nipples will be at a 90 degree angle with the stock setup. With an external WG, they'll be in a straight line. Check Badog's topic/info request on this. https://www.rx7club.com/forum/showth...hreadid=127983 I posted apexi's diagram there.
Michel
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Joined: Mar 2001
Posts: 2,311
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From: Florida
LOL, don't mind at all. I figured that's what you were doing. Just an update, I did switch the ports and that solved my boost (or lack thereof) problem. It's still very "untuned" but I was able to get 9kg/cm2 between 3-4K rpm.
I managed to run into another snafu on the way to an assignment tonight. Since I had to take the highway, I thought it would be a good opportunity to do a bit more tuning and test response out. That was all good until a sustained 4th gear run at 1.05kg/cm2 burst the "temporary" hose I have going from the turbo discharge to the IC pipe. It was a huge bang/pop. I almost crapped myself until I realized it was the hose that burst and not an apex seal :-) Now I'll have to locate something else to use until I can have a 90 degree elbow welded on, sigh...Wonder if GReddy sells elbows seperately.
Michel
I managed to run into another snafu on the way to an assignment tonight. Since I had to take the highway, I thought it would be a good opportunity to do a bit more tuning and test response out. That was all good until a sustained 4th gear run at 1.05kg/cm2 burst the "temporary" hose I have going from the turbo discharge to the IC pipe. It was a huge bang/pop. I almost crapped myself until I realized it was the hose that burst and not an apex seal :-) Now I'll have to locate something else to use until I can have a 90 degree elbow welded on, sigh...Wonder if GReddy sells elbows seperately.
Michel
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