My personal sequential boost thread, from broke to hopefully fixed
03-03-12, 11:40 AM
#26
I realize you're getting the stock 'y' pipe coupler for cost, but personally I would re-consider getting an efini 'Y'. Mazda realized the engineering mistake and as you've already mentioned, it flows better. How much? Not sure...probably not much. But it's definitely positive and a permanent fix for potential leaks at that coupler. Over the long term maybe even slightly easier on your turbos. It's also OEM so you don't have to worry about fitment or using sub-par quality aftermarket.
It's rare but you might also check for any leaks in your pressure chamber and vacuum chambers.
My .02
It's rare but you might also check for any leaks in your pressure chamber and vacuum chambers.
My .02
03-03-12, 02:51 PM
#27
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I realize you're getting the stock 'y' pipe coupler for cost, but personally I would re-consider getting an efini 'Y'. Mazda realized the engineering mistake and as you've already mentioned, it flows better. How much? Not sure...probably not much. But it's definitely positive and a permanent fix for potential leaks at that coupler. Over the long term maybe even slightly easier on your turbos. It's also OEM so you don't have to worry about fitment or using sub-par quality aftermarket.
It's rare but you might also check for any leaks in your pressure chamber and vacuum chambers.
My .02
It's rare but you might also check for any leaks in your pressure chamber and vacuum chambers.
My .02
Great to hear from you and thanks for the input! I really agree with you, and will get an Efini Y pipe soon. That hose coupler was 20-something bucks and quickly available for me, so I went that route. I do have all intentions of replacing it with an Efini.
BTW, your engine bay is looking quite amazing. I am very envious
See you around this year!Trev
03-03-12, 09:03 PM
#28
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Another update...
Okay, so I started and drove the car for the first time since replacing all OEM hoses associated with the stock intake box and the vac lines also associated with the crv and abv, and also with the new HKS Intercooler hardpipes and new hoses couplers to connect them. This is also the first drive since I installed my car's first mod, the Downpipe and new O2 sensor.
First off, the pre-cat was 150k miles old, as well as the O2 sensor. I must say, the car idled and accelerated MUCH more smoothly. MUCH MORE. I am still experiencing only 4-5 PSI of boost however that begins to drop off between 4000-4500 RPMS. The boost is much smoother feeling, although I still have problems to solve.
I guess from all of my reading, the car SHOULD boost at least 7 with no boost leaks
I have none at all that I can find, although I noticed that the VAC line going from the PURGE CONTROL SOLENOID is VERY loosely connected to its nipple which is under the UIM where it joins the throttle body...the VAC line is too big of an Inner Diameter for the nipple it is supposed to fit on...it slides on and off with no effort, but doesn't disconnect. With the car on and idling I can here a whistle from that line and if I move the vac line in and out on the nipple I can make the whistle non-existent.
So, I am quite confused as to why I can only achieve a max of 4-5 psi in all gears and then have it bleed between 4000 and 4500 rpms...
I am enjoying doing this one thing at a time though so hopefully I can pinpoint the exact cause...
Trev
First off, the pre-cat was 150k miles old, as well as the O2 sensor. I must say, the car idled and accelerated MUCH more smoothly. MUCH MORE. I am still experiencing only 4-5 PSI of boost however that begins to drop off between 4000-4500 RPMS. The boost is much smoother feeling, although I still have problems to solve.
I guess from all of my reading, the car SHOULD boost at least 7 with no boost leaks
I have none at all that I can find, although I noticed that the VAC line going from the PURGE CONTROL SOLENOID is VERY loosely connected to its nipple which is under the UIM where it joins the throttle body...the VAC line is too big of an Inner Diameter for the nipple it is supposed to fit on...it slides on and off with no effort, but doesn't disconnect. With the car on and idling I can here a whistle from that line and if I move the vac line in and out on the nipple I can make the whistle non-existent.
So, I am quite confused as to why I can only achieve a max of 4-5 psi in all gears and then have it bleed between 4000 and 4500 rpms...
I am enjoying doing this one thing at a time though so hopefully I can pinpoint the exact cause...
Trev
03-04-12, 06:58 PM
#29
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UPDATE!
I removed my UIM today to inspect the vacuum lines that have already been replaced before I bought the car, and to test the solenoids and the turbo control and WG control solenoids. Well, there was a vac line that connects to the second solenoid from the firewall, Relief 1, that wasn't even connected. Also, after checking all the solenoids, I found solenoid H (on the colored diagram from my first post) the Charge Relief Solenoid to be dead. No clicking, no functioning. I reconnected the hose on the relief 1 solenoid and will now be getting another Charge Relief Solenoid to replace my dead one.
Are any of these two issues a possible cause for my issues? After I replace that solenoid, I will button it back up and check the WG actuators and lines to them under the intake box. I was to make sure there are pills in the lines.
Trev
I removed my UIM today to inspect the vacuum lines that have already been replaced before I bought the car, and to test the solenoids and the turbo control and WG control solenoids. Well, there was a vac line that connects to the second solenoid from the firewall, Relief 1, that wasn't even connected. Also, after checking all the solenoids, I found solenoid H (on the colored diagram from my first post) the Charge Relief Solenoid to be dead. No clicking, no functioning. I reconnected the hose on the relief 1 solenoid and will now be getting another Charge Relief Solenoid to replace my dead one.
Are any of these two issues a possible cause for my issues? After I replace that solenoid, I will button it back up and check the WG actuators and lines to them under the intake box. I was to make sure there are pills in the lines.
Trev
03-04-12, 09:17 PM
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Glad we could hopefully pin-point a possible cause on both the UN-attached vac hose and the solenoid. Let me know when you want help re-assembling. I always forgot a sensor or vac line when hooking everything back up.
Seda
Seda
03-04-12, 09:28 PM
#31
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Trev
03-04-12, 09:52 PM
#32
A boost leak pressure test may help you find any remaining little stupid leaks. Fighter's Garage used to sell a pressure testing tool for an FD with stock twins. It should just be some PVC type of thing you stick in the turbo inlet pipes, one of which is tapped for an air fitting. This site sells them for the 300zx: www.boostpro.net/prodtester.html
I have not done it on a car with stock twins before but that would be a method to track down any other nagging problems.
It's hard to say what a dead charge relief solenoid would do because we don't know exactly what's going on with your turbo system. The secondary turbo would go into surge briefly without the charge relief valve working, but I think that's the least of your worries, and there is reason to believe that the stock turbos can tolerate some surge. If the charge relief solenoid had been hooked up incorrectly, it is possible that vacuum could have been continuously applied to the charge relief valve, making eseentially a huge boost leak. The charge relief valve is basically a blowoff valve controlled by the ECU through a vacuum solenoid.
Also, it doesn't surprise me that installing a downpipe made a noticeable difference. These cats weren't built to last, not by today's standards. Only modern vehicles with the strictest emissions certification have cats meant to last 150k.
I have not done it on a car with stock twins before but that would be a method to track down any other nagging problems.
It's hard to say what a dead charge relief solenoid would do because we don't know exactly what's going on with your turbo system. The secondary turbo would go into surge briefly without the charge relief valve working, but I think that's the least of your worries, and there is reason to believe that the stock turbos can tolerate some surge. If the charge relief solenoid had been hooked up incorrectly, it is possible that vacuum could have been continuously applied to the charge relief valve, making eseentially a huge boost leak. The charge relief valve is basically a blowoff valve controlled by the ECU through a vacuum solenoid.
Also, it doesn't surprise me that installing a downpipe made a noticeable difference. These cats weren't built to last, not by today's standards. Only modern vehicles with the strictest emissions certification have cats meant to last 150k.
03-05-12, 05:11 PM
#33
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A boost leak pressure test may help you find any remaining little stupid leaks. Fighter's Garage used to sell a pressure testing tool for an FD with stock twins. It should just be some PVC type of thing you stick in the turbo inlet pipes, one of which is tapped for an air fitting. This site sells them for the 300zx: www.boostpro.net/prodtester.html
I have not done it on a car with stock twins before but that would be a method to track down any other nagging problems.
It's hard to say what a dead charge relief solenoid would do because we don't know exactly what's going on with your turbo system. The secondary turbo would go into surge briefly without the charge relief valve working, but I think that's the least of your worries, and there is reason to believe that the stock turbos can tolerate some surge. If the charge relief solenoid had been hooked up incorrectly, it is possible that vacuum could have been continuously applied to the charge relief valve, making eseentially a huge boost leak. The charge relief valve is basically a blowoff valve controlled by the ECU through a vacuum solenoid.
Also, it doesn't surprise me that installing a downpipe made a noticeable difference. These cats weren't built to last, not by today's standards. Only modern vehicles with the strictest emissions certification have cats meant to last 150k.
I have not done it on a car with stock twins before but that would be a method to track down any other nagging problems.
It's hard to say what a dead charge relief solenoid would do because we don't know exactly what's going on with your turbo system. The secondary turbo would go into surge briefly without the charge relief valve working, but I think that's the least of your worries, and there is reason to believe that the stock turbos can tolerate some surge. If the charge relief solenoid had been hooked up incorrectly, it is possible that vacuum could have been continuously applied to the charge relief valve, making eseentially a huge boost leak. The charge relief valve is basically a blowoff valve controlled by the ECU through a vacuum solenoid.
Also, it doesn't surprise me that installing a downpipe made a noticeable difference. These cats weren't built to last, not by today's standards. Only modern vehicles with the strictest emissions certification have cats meant to last 150k.
Yes, I believe it is the least of my worries, but I would think that it could cause transitionary issues between primary and secondary. Not saying it fixes my issue, because I have only 4-5psi max to redline on the primary, but it may at least be an issue as to why I have no transition. Thanks!
Trev
03-05-12, 07:29 PM
#34
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Just ordered my Black Silcone Vacuum hose kit...doing the whole kit n' kaboodle while checking all of the solenoids. Need to get all of these basics perfectly right so I can really start to dial in and get this issue fixed. More to come...
Trev
Trev
03-07-12, 06:39 PM
#35
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Progress update
I am diving deeper and deeper into this issue and basically I seem to be on a mission to replace as many things as possible (not always by choice) as I find things either broken or if I break them. I did find that the VAC hose that goes from the TOP nipple of the Pressure Regulator Solenoid (the FIRST solenoid from the firewall in the rat's nest) was completely separated where it connects to the LIM by the fuel rail...I am sure that wasn't helping my cause
I have removed so much stuff I feel like I am doing a rebuild. Alternator, oil pedestal, air pump etc, all intake items, ACV, etc. I did notice that the line to the VACUUM chamber is rock hard and slides EASILY on and off the nipple, clearly not sealed. Of course, I accidently broke that VACUUM chamber nipple when removing the pedestal, so I need to remove some more items to remove that and replace it. Here is what I am looking at purchasing now while I have all of this opened up:
-NEW PRESSURE CHAMBER
-NEW VACUUM CHAMBER
-ALL NEW SOLENOIDS IN THE RATS NEST (I just hate having to replace these with other used ones that I don't know how much life is left on them)
-STAINLESS STEEL OMP LINES
-VARIOUS COOLANT LINES
Somehow, one of the two wires on my Altnernator plug (grey square one) broke right at the connector, so I need to find another plug I can solder on.
I am VERY tempted to buy an all new engine wiring harness...
Until next time...
Trev
I have removed so much stuff I feel like I am doing a rebuild. Alternator, oil pedestal, air pump etc, all intake items, ACV, etc. I did notice that the line to the VACUUM chamber is rock hard and slides EASILY on and off the nipple, clearly not sealed. Of course, I accidently broke that VACUUM chamber nipple when removing the pedestal, so I need to remove some more items to remove that and replace it. Here is what I am looking at purchasing now while I have all of this opened up:
-NEW PRESSURE CHAMBER
-NEW VACUUM CHAMBER
-ALL NEW SOLENOIDS IN THE RATS NEST (I just hate having to replace these with other used ones that I don't know how much life is left on them)
-STAINLESS STEEL OMP LINES
-VARIOUS COOLANT LINES
Somehow, one of the two wires on my Altnernator plug (grey square one) broke right at the connector, so I need to find another plug I can solder on.
I am VERY tempted to buy an all new engine wiring harness...
Until next time...
Trev
03-07-12, 08:18 PM
#36
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If the line to the vacuum tank was not fitting well, that very well could be part of the problem. You do need that vacuum tank.
Unless the OMP lines are broken, don't replace them. It is a BITCH to do the OMP lines in the car, they are secured under the water pump housing. I'm also not a fan of the stainless OMP lines - braided stainless is abrasive and can cause other problems. Also, they aren't molded to fit like the stock lines. The stock lines work VERY well and last a VERY long time. Most likely the stainless lines will look like terrible in 100,000 miles.
The alternator connector is available online (Google around) or at a junkyard for free/cheap.
I wouldn't purchase all NEW solenoids, I'd get good low-mileage ones. Or get ones off an FC, they see a lot less heat and are the same exact thing.
Dale
Unless the OMP lines are broken, don't replace them. It is a BITCH to do the OMP lines in the car, they are secured under the water pump housing. I'm also not a fan of the stainless OMP lines - braided stainless is abrasive and can cause other problems. Also, they aren't molded to fit like the stock lines. The stock lines work VERY well and last a VERY long time. Most likely the stainless lines will look like terrible in 100,000 miles.
The alternator connector is available online (Google around) or at a junkyard for free/cheap.
I wouldn't purchase all NEW solenoids, I'd get good low-mileage ones. Or get ones off an FC, they see a lot less heat and are the same exact thing.
Dale
03-07-12, 09:37 PM
#37
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If the line to the vacuum tank was not fitting well, that very well could be part of the problem. You do need that vacuum tank.
Unless the OMP lines are broken, don't replace them. It is a BITCH to do the OMP lines in the car, they are secured under the water pump housing. I'm also not a fan of the stainless OMP lines - braided stainless is abrasive and can cause other problems. Also, they aren't molded to fit like the stock lines. The stock lines work VERY well and last a VERY long time. Most likely the stainless lines will look like terrible in 100,000 miles.
The alternator connector is available online (Google around) or at a junkyard for free/cheap.
I wouldn't purchase all NEW solenoids, I'd get good low-mileage ones. Or get ones off an FC, they see a lot less heat and are the same exact thing.
Dale
Unless the OMP lines are broken, don't replace them. It is a BITCH to do the OMP lines in the car, they are secured under the water pump housing. I'm also not a fan of the stainless OMP lines - braided stainless is abrasive and can cause other problems. Also, they aren't molded to fit like the stock lines. The stock lines work VERY well and last a VERY long time. Most likely the stainless lines will look like terrible in 100,000 miles.
The alternator connector is available online (Google around) or at a junkyard for free/cheap.
I wouldn't purchase all NEW solenoids, I'd get good low-mileage ones. Or get ones off an FC, they see a lot less heat and are the same exact thing.
Dale
Trev
03-07-12, 11:45 PM
#38
To further quantify this, lets say your setup flows 40#/minute of air; this could represent a car of 300 or so RWHP. The test results suggest an additional 6#/min could move through this portion of the tract with no additional pressure required [from the turbos] to push it. This is much more efficient and may represent a noticeable improvement for you guys that already have a low restriction intake tract, IC, plumbing, etc., and who are trying to extract all the potential from your setup. *Note that I am not saying that it will give you 6#/min more flow just by bolting it on.* It will improve your boost/flow potential, however.
And while on the subject of Y pipes, here's a note for those of you who have tried to divide the Y pipe internally: Not a good idea, it will generally result in a loss of flow. I know this because I have built and tested some variants.
And of course the Efini pipe gets rid of that problematic coupler....
03-11-12, 09:52 AM
#41
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Lots of parts arriving. I got a new pressure and vacuum chamber (slightly used) and another rats nest with all solenoids that have only 8k proven miles on them! Also, new drive belts, all new metal gaskets, FC thermoswitch, new oem thermostat and a few other maintenance items.
Will be getting things put back together this week.
Trev
Will be getting things put back together this week.
Trev
03-11-12, 05:54 PM
#42
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Good work, hopefully all that sorts your problem.
Iv just finished a mission into the rats nest myself this past weekend.
I had quite a few hoses that had gone hard and didnt really grip the solenoid properly.
I also had a worm drive hose clamp on the intercooler piping that was broken and could only be done up so tight, which wasent tight enough - resulting in a boost leak.
Car is more responsive and faster than ever! hurahh!
I was also getting idle problems, car was idling low at about 500rpm.
Idle is solid and up to just over 1k rpm now.
Before my hose job i was going to adjust my idle speed up, now ill adjust it down.
Hopefully its not a vacuum leak
Either way car is alot faster!
EDIT: ah and i used to get alot of backfiring when changing gears, havent had a single backfire since the hose job.
Iv just finished a mission into the rats nest myself this past weekend.
I had quite a few hoses that had gone hard and didnt really grip the solenoid properly.
I also had a worm drive hose clamp on the intercooler piping that was broken and could only be done up so tight, which wasent tight enough - resulting in a boost leak.
Car is more responsive and faster than ever! hurahh!
I was also getting idle problems, car was idling low at about 500rpm.
Idle is solid and up to just over 1k rpm now.
Before my hose job i was going to adjust my idle speed up, now ill adjust it down.
Hopefully its not a vacuum leak
Either way car is alot faster!EDIT: ah and i used to get alot of backfiring when changing gears, havent had a single backfire since the hose job.
Last edited by 96fd3s; 03-11-12 at 06:14 PM.
03-11-12, 08:12 PM
#43
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Good work, hopefully all that sorts your problem.
Iv just finished a mission into the rats nest myself this past weekend.
I had quite a few hoses that had gone hard and didnt really grip the solenoid properly.
I also had a worm drive hose clamp on the intercooler piping that was broken and could only be done up so tight, which wasent tight enough - resulting in a boost leak.
Car is more responsive and faster than ever! hurahh!
I was also getting idle problems, car was idling low at about 500rpm.
Idle is solid and up to just over 1k rpm now.
Before my hose job i was going to adjust my idle speed up, now ill adjust it down.
Hopefully its not a vacuum leak Either way car is alot faster!
EDIT: ah and i used to get alot of backfiring when changing gears, havent had a single backfire since the hose job.
Iv just finished a mission into the rats nest myself this past weekend.
I had quite a few hoses that had gone hard and didnt really grip the solenoid properly.
I also had a worm drive hose clamp on the intercooler piping that was broken and could only be done up so tight, which wasent tight enough - resulting in a boost leak.
Car is more responsive and faster than ever! hurahh!
I was also getting idle problems, car was idling low at about 500rpm.
Idle is solid and up to just over 1k rpm now.
Before my hose job i was going to adjust my idle speed up, now ill adjust it down.
Hopefully its not a vacuum leak
Either way car is alot faster!EDIT: ah and i used to get alot of backfiring when changing gears, havent had a single backfire since the hose job.
Trev
03-16-12, 03:32 PM
#44
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Progress report
Okay, I am on the mend here, getting everything put back together. First off, I really can't even understand how my car ran as well as it did with as many completely broken off solenoid nipples and broken in half vacuum lines I have found!! The rats nest has new lines and is back in the car along with the ACV, FC thermoswitch, new vacuum chamber and new (8k miles on them) solenoids. I am getting excited to get it wrapped up and take it for a drive. More to come as I get further. I am 110% sure this vacuum line job WILL fix my issues...
Trev
Trev
03-16-12, 05:30 PM
#45
RX-7 Bad Ass
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As a buddy of mine used to say, "That may not be the problem, but it sure as hell wasn't helping things".
Hopefully you'll have some good updates soon!
Dale
Hopefully you'll have some good updates soon!
Dale
03-16-12, 07:23 PM
#46
Read this, and test accordingly:
http://www.autosportracetech.com/RX-...leshooting.htm
http://rx7.voodoobox.net/howto/solen...oid_check.html
:-) neil
http://www.autosportracetech.com/RX-...leshooting.htm
http://rx7.voodoobox.net/howto/solen...oid_check.html
:-) neil
03-20-12, 08:55 PM
#47
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New thermostat installed, everything else all dOne basically. Only thing left is to install new WG and PC lines with pills (got new ones...mine were missing...again, not helping the situation). I will do this tonight! Update tomorrow as it is raining and the street is wet!
Trev
Trev
03-20-12, 11:45 PM
#48
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WE HAVE BOOST!! Just too much...
Okay, we'll the surgery was a success. The car fired right up and idled/drove very nicely. Keep in mind the car only has IC hard pipes and a DP. The only thing that I am dealing with now Is the boost pattern. It was easiest to really measure a second gear pull tonight, and it was a 14-6-10. I did replace all vacuum lines including new OEM WG and turbo pre control lines with new boost pills built in. I guess I am excited that the secondary is 10, but I need to scale back the primary and bring that transition up. Right now, an 8 psi swing from primary to transition doesn't feel nice and smooth
So, I am pleased to say that after the vacuum line job and newer solenoids, I am finally in the ball park here. I will continue to update this thread as I resolve the primary and transition issue.
Trev
So, I am pleased to say that after the vacuum line job and newer solenoids, I am finally in the ball park here. I will continue to update this thread as I resolve the primary and transition issue.
Trev
03-21-12, 01:43 AM
#49
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Knock sensor
So, I took a look at the vac lines going to the turbo actuator under the turbos and sure enough I forgot to replace both of those lines and one was popped off. I replaced both lines and went for a drive. It seems smoother, but I am still getting 14-15 on primary, then 6-7 transition then 10-11 on secondary (this time that holds, no bleed off). However, I must have gotten too spirited because I tripped the knock sensor during boost and got a code 05 and it went limp all the way home. I reset the ecu to get rid of the code, but I am still stuck with my primary boosting too high and my transition being too low and something causing my KS to trip...
Trev
Trev
03-21-12, 03:16 AM
#50
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!