My personal sequential boost thread, from broke to hopefully fixed
Thread Starter
Joined: Sep 2003
Posts: 982
Likes: 0
From: Yutan, Nebraska
Trev,
It appears you've made some good progress! Even the most perfect of rx7s always seem to have hidden issues. I picked up my 93 touring with 38k on it. Upon installation of my boost gauge I discovered I was only hitting 5 psi in first and a every-now-and-then transition in second. Third had a slow transition. As I was tearing into my engine bay to replace my vacuum lines and install Azeknightz solenoid rack, I ended up replacing a lot of things! I wish I could have seen your thread a few days ago and I would have suggested testing your omp nozzles while you were there. Both of mine had failed check valves. After buttoning up including the installation of a nice 3" Pettit downpipe, I got full boost an transition in all gears. I do however now have a 13-8-10 boost pattern. I attribute the spike to the 3" downpipe. My plan to quell that spike is the dual MBC set up as suggested by I believe it was Damien. You can find the link in the FAQ. I believe dual MBCs will trump a single ebc in terms of full control over transition. I'm a set it and forget it kind of guy
.
Good luck to you!
It appears you've made some good progress! Even the most perfect of rx7s always seem to have hidden issues. I picked up my 93 touring with 38k on it. Upon installation of my boost gauge I discovered I was only hitting 5 psi in first and a every-now-and-then transition in second. Third had a slow transition. As I was tearing into my engine bay to replace my vacuum lines and install Azeknightz solenoid rack, I ended up replacing a lot of things! I wish I could have seen your thread a few days ago and I would have suggested testing your omp nozzles while you were there. Both of mine had failed check valves. After buttoning up including the installation of a nice 3" Pettit downpipe, I got full boost an transition in all gears. I do however now have a 13-8-10 boost pattern. I attribute the spike to the 3" downpipe. My plan to quell that spike is the dual MBC set up as suggested by I believe it was Damien. You can find the link in the FAQ. I believe dual MBCs will trump a single ebc in terms of full control over transition. I'm a set it and forget it kind of guy
. Good luck to you!
Thanks for the info. I guess I am not aware of check valves in the omp
Thread Starter
Joined: Sep 2003
Posts: 982
Likes: 0
From: Yutan, Nebraska
Trev,
It appears you've made some good progress! Even the most perfect of rx7s always seem to have hidden issues. I picked up my 93 touring with 38k on it. Upon installation of my boost gauge I discovered I was only hitting 5 psi in first and a every-now-and-then transition in second. Third had a slow transition. As I was tearing into my engine bay to replace my vacuum lines and install Azeknightz solenoid rack, I ended up replacing a lot of things! I wish I could have seen your thread a few days ago and I would have suggested testing your omp nozzles while you were there. Both of mine had failed check valves. After buttoning up including the installation of a nice 3" Pettit downpipe, I got full boost an transition in all gears. I do however now have a 13-8-10 boost pattern. I attribute the spike to the 3" downpipe. My plan to quell that spike is the dual MBC set up as suggested by I believe it was Damien. You can find the link in the FAQ. I believe dual MBCs will trump a single ebc in terms of full control over transition. I'm a set it and forget it kind of guy.
Good luck to you!
It appears you've made some good progress! Even the most perfect of rx7s always seem to have hidden issues. I picked up my 93 touring with 38k on it. Upon installation of my boost gauge I discovered I was only hitting 5 psi in first and a every-now-and-then transition in second. Third had a slow transition. As I was tearing into my engine bay to replace my vacuum lines and install Azeknightz solenoid rack, I ended up replacing a lot of things! I wish I could have seen your thread a few days ago and I would have suggested testing your omp nozzles while you were there. Both of mine had failed check valves. After buttoning up including the installation of a nice 3" Pettit downpipe, I got full boost an transition in all gears. I do however now have a 13-8-10 boost pattern. I attribute the spike to the 3" downpipe. My plan to quell that spike is the dual MBC set up as suggested by I believe it was Damien. You can find the link in the FAQ. I believe dual MBCs will trump a single ebc in terms of full control over transition. I'm a set it and forget it kind of guy
. Good luck to you!
Thanks for the info. I guess I am not aware of check valves in the omp nozzle lines?? I guess I will probably end up with dual mbc as well to bring the primary boost back down to 10. Still not sure why I have a 6 psi dip instead of 8. All of my rats nest solenoids tested perfect and have only 8k. Miles on them. Also, my two green turbo control solenoids on the front of the manifold tested fine as well. Too bad I just bought the new WG and Turbo PC lines with pills in them if I am going to go mbc.
The check valves are built into the OMP nozzles. They are in place to allow oil metering under pressurized [boost] conditions. A simple test on them is the "blow both ways" test. Even at 38k miles, both of mine had failed! It is DIRE that these check valves be operational as they are imperative to the proper metering of oil via your OMP. If the valves are failed, then under pressurized conditions the motor will simply spit the provided oil back through the breather and into your primary turbo inlet pipe. Have you noticed oily film in your intercooler piping? I personally replaced my nozzles as they were I believe $40 for both. However in the future, should they fail again I plan to run one of DaleClarks fancy check valves tee'd to both nozzles externally to achieve the same effect.
Back to being on topic, most people suggest that adding a downpipe will NOT attribute to any boost issues. In my case I have noticed a spike on the primary turbo and have decided to get independent MBCs for each turbo [primary and secondary]. This will provide a full control over the sequential operation.
I personally replaced my nozzles as they were I believe $40 for both. However in the future, should they fail again I plan to run one of DaleClarks fancy check valves tee'd to both nozzles externally to achieve the same effect. Back to being on topic, most people suggest that adding a downpipe will NOT attribute to any boost issues. In my case I have noticed a spike on the primary turbo and have decided to get independent MBCs for each turbo [primary and secondary]. This will provide a full control over the sequential operation.
Thread Starter
Joined: Sep 2003
Posts: 982
Likes: 0
From: Yutan, Nebraska
The check valves are built into the OMP nozzles. They are in place to allow oil metering under pressurized [boost] conditions. A simple test on them is the "blow both ways" test. Even at 38k miles, both of mine had failed! It is DIRE that these check valves be operational as they are imperative to the proper metering of oil via your OMP. If the valves are failed, then under pressurized conditions the motor will simply spit the provided oil back through the breather and into your primary turbo inlet pipe. Have you noticed oily film in your intercooler piping? I personally replaced my nozzles as they were I believe $40 for both. However in the future, should they fail again I plan to run one of DaleClarks fancy check valves tee'd to both nozzles externally to achieve the same effect.
Back to being on topic, most people suggest that adding a downpipe will NOT attribute to any boost issues. In my case I have noticed a spike on the primary turbo and have decided to get independent MBCs for each turbo [primary and secondary]. This will provide a full control over the sequential operation.
I personally replaced my nozzles as they were I believe $40 for both. However in the future, should they fail again I plan to run one of DaleClarks fancy check valves tee'd to both nozzles externally to achieve the same effect. Back to being on topic, most people suggest that adding a downpipe will NOT attribute to any boost issues. In my case I have noticed a spike on the primary turbo and have decided to get independent MBCs for each turbo [primary and secondary]. This will provide a full control over the sequential operation.
I don't have it in me to tear this apart again right now to check those omp nozzles, but will soon. I am going to just do the MBC that Damian did and go that route. I may try the home depot method, an if that doesn't work well, I will get what he described.
Trev
Glad to hear you have boost!
With too much on the primary turbo you may have something going on with your factory boost control. I assume you have the pills in the lines, they're installed right and not plugged or anything, lines are tight with no air leaks? Also, make sure the plugs going to the boost control solenoids aren't swapped, it's easy to do and does weird stuff.
Of course, a manual or electronic boost controller will get around all those problems.
Dale
With too much on the primary turbo you may have something going on with your factory boost control. I assume you have the pills in the lines, they're installed right and not plugged or anything, lines are tight with no air leaks? Also, make sure the plugs going to the boost control solenoids aren't swapped, it's easy to do and does weird stuff.
Of course, a manual or electronic boost controller will get around all those problems
.Dale
Thread Starter
Joined: Sep 2003
Posts: 982
Likes: 0
From: Yutan, Nebraska
Glad to hear you have boost!
With too much on the primary turbo you may have something going on with your factory boost control. I assume you have the pills in the lines, they're installed right and not plugged or anything, lines are tight with no air leaks? Also, make sure the plugs going to the boost control solenoids aren't swapped, it's easy to do and does weird stuff.
Of course, a manual or electronic boost controller will get around all those problems.
Dale
With too much on the primary turbo you may have something going on with your factory boost control. I assume you have the pills in the lines, they're installed right and not plugged or anything, lines are tight with no air leaks? Also, make sure the plugs going to the boost control solenoids aren't swapped, it's easy to do and does weird stuff.
Of course, a manual or electronic boost controller will get around all those problems
.Dale
The two boost lines that have the pills are brand spankin' new. I have them installed so that the pill is closer to the turbo compressor housing on each line. I am certain my turbo control solenoids are plugged in perfect. I really think that the DP is having something to do with it...
All lines are secure and triple checked.
Trev
Surprisingly enough you won't need to tear into you UIM to test your omp nozzles On your primary TIP (turbo inlet pipe) there are two nipples, one of which is the breather side of your OMP nozzles! If you follow your vacuum diagram you can find it. If you can blow through the hose and not suck through it, you're in good shape if not, add a check valve to that line and you'll be golden. On the note of omp lubrication, premixing is always a good idea.
Matt
On your primary TIP (turbo inlet pipe) there are two nipples, one of which is the breather side of your OMP nozzles! If you follow your vacuum diagram you can find it. If you can blow through the hose and not suck through it, you're in good shape if not, add a check valve to that line and you'll be golden. On the note of omp lubrication, premixing is always a good idea. Matt
Thread Starter
Joined: Sep 2003
Posts: 982
Likes: 0
From: Yutan, Nebraska
Surprisingly enough you won't need to tear into you UIM to test your omp nozzles On your primary TIP (turbo inlet pipe) there are two nipples, one of which is the breather side of your OMP nozzles! If you follow your vacuum diagram you can find it. If you can blow through the hose and not suck through it, you're in good shape if not, add a check valve to that line and you'll be golden. On the note of omp lubrication, premixing is always a good idea.
Matt
On your primary TIP (turbo inlet pipe) there are two nipples, one of which is the breather side of your OMP nozzles! If you follow your vacuum diagram you can find it. If you can blow through the hose and not suck through it, you're in good shape if not, add a check valve to that line and you'll be golden. On the note of omp lubrication, premixing is always a good idea. Matt
Trev,
A manual boost controller on your wastegate line should allow you to lower your boost to where you want it. Adding a controller to the prespool line complicates things dramatically. I would leave the prespool line alone (experience speaking).
A 3rd gear pull (rather than 2nd) is normally a better way yo test your boost. 2nd gear happens so fast that the control system doesn't get a chance to take over as well as 3rd gear. I would test in 3rd before doing anything.
A manual boost controller on your wastegate line should allow you to lower your boost to where you want it. Adding a controller to the prespool line complicates things dramatically. I would leave the prespool line alone (experience speaking).
A 3rd gear pull (rather than 2nd) is normally a better way yo test your boost. 2nd gear happens so fast that the control system doesn't get a chance to take over as well as 3rd gear. I would test in 3rd before doing anything.
Thread Starter
Joined: Sep 2003
Posts: 982
Likes: 0
From: Yutan, Nebraska
Trev,
A manual boost controller on your wastegate line should allow you to lower your boost to where you want it. Adding a controller to the prespool line complicates things dramatically. I would leave the prespool line alone (experience speaking).
A 3rd gear pull (rather than 2nd) is normally a better way yo test your boost. 2nd gear happens so fast that the control system doesn't get a chance to take over as well as 3rd gear. I would test in 3rd before doing anything.
A manual boost controller on your wastegate line should allow you to lower your boost to where you want it. Adding a controller to the prespool line complicates things dramatically. I would leave the prespool line alone (experience speaking).
A 3rd gear pull (rather than 2nd) is normally a better way yo test your boost. 2nd gear happens so fast that the control system doesn't get a chance to take over as well as 3rd gear. I would test in 3rd before doing anything.
Thanks for the advice, I appreciate it. I did forget to mention that I did do some third gear pulls and achieved the same results as IIRC. I will try again today though an see my results. Taking a look at Damian's thread on the Hallman MBC, he put a controller on both and seemed to be able to dial it in nicely. Are you thinking just leave the PC factory line with the pill in it connected, then just use the Hallman for the WG and start there? I could see that being a good plan, save me a little $$$ for a second MBC. If it works, then I know I don't need to proceed further.
Trev
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