DIY preliminary results
#21
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I think I've threadjacked a couple of times, so it's payback.
I would suggest using heater hose to mock up the length then use it as a shield for the braided steel. My line is around 40" and I wish it was a bit longer. 48" sounds fine.
Even though my line accidentally clears the hood, a 90° fitting would have been better than the 45° 1/8npt to -4AN that I used.
I would suggest using heater hose to mock up the length then use it as a shield for the braided steel. My line is around 40" and I wish it was a bit longer. 48" sounds fine.
Even though my line accidentally clears the hood, a 90° fitting would have been better than the 45° 1/8npt to -4AN that I used.
#22
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Update
After street driving, two autox's and a night at the dragstrip all is good.
A few notes:
-The cheap ebay T3/T4 is awesome. Boost onset is in the 2500 range and is very docile driving at low (sub 4k) rpms. I think the full 3" exhaust has a lot to do with the early spool. 10psi feels really good.
-The full 3" exhaust is near silent - until the vta wg opens, then it's another story.
-Best mileage on an 85% highway loop was 33.0mpg.
-With huge lag (more on this later) between shifts and 195/60-14 Fuzions, it wheelhopped (more on this too) to a 1.99 60' and a 13.29@105.4. 602', hot and humid. Weight was 2570lbs going down the track. In NA trim it was 2400lbs. Apparently I added a lot of weight. The hp calculator showed that if I didn't have the big lag between shifts the hp vs weight should have netted a 12.93. This is around 9-10psi, not sure, didn't datalog. I'll go back to the track after I fix the wheel hop.
-The wg signal was being referenced to the tap on the turbine. There were times when the wg was opening as I was lifting. Changing the reference to the manifold solved the issue and between shift lag is almost nil.
-The bov is open at cruise. I think it is the culprit for my unstable cruise afr's. I might add a solenoid to the bov signal line and cut it when I'm in closed loop, let it operate normally in all other conditions.
-I get massive wheel hop at the drag strip and when launching at the autox. I have some urethane differential mounts on order, I'll report on how they do.
-Vented hoods are not pretty or stealthy but the functionality makes up for it.
-So far, no cracks and no failures of any of the cheap ebay chinese turbo, intercooler, bov, wg, manifold. The turbo and wg are braced.
-Can't wait to turn the boost up but won't until I have more details on what it takes to put the RX-7 trans guts into the Miata. If anyone has done this, please steer me to the info.
A few notes:
-The cheap ebay T3/T4 is awesome. Boost onset is in the 2500 range and is very docile driving at low (sub 4k) rpms. I think the full 3" exhaust has a lot to do with the early spool. 10psi feels really good.
-The full 3" exhaust is near silent - until the vta wg opens, then it's another story.
-Best mileage on an 85% highway loop was 33.0mpg.
-With huge lag (more on this later) between shifts and 195/60-14 Fuzions, it wheelhopped (more on this too) to a 1.99 60' and a 13.29@105.4. 602', hot and humid. Weight was 2570lbs going down the track. In NA trim it was 2400lbs. Apparently I added a lot of weight. The hp calculator showed that if I didn't have the big lag between shifts the hp vs weight should have netted a 12.93. This is around 9-10psi, not sure, didn't datalog. I'll go back to the track after I fix the wheel hop.
-The wg signal was being referenced to the tap on the turbine. There were times when the wg was opening as I was lifting. Changing the reference to the manifold solved the issue and between shift lag is almost nil.
-The bov is open at cruise. I think it is the culprit for my unstable cruise afr's. I might add a solenoid to the bov signal line and cut it when I'm in closed loop, let it operate normally in all other conditions.
-I get massive wheel hop at the drag strip and when launching at the autox. I have some urethane differential mounts on order, I'll report on how they do.
-Vented hoods are not pretty or stealthy but the functionality makes up for it.
-So far, no cracks and no failures of any of the cheap ebay chinese turbo, intercooler, bov, wg, manifold. The turbo and wg are braced.
-Can't wait to turn the boost up but won't until I have more details on what it takes to put the RX-7 trans guts into the Miata. If anyone has done this, please steer me to the info.
#24
That's one badass ebay setup. ching chong
I used 47" and It is a little long. If i was going to do it again I would make it shorter but just because I don't like clutter. I advise paying the extra money for swivel fittings on the line because it has a permanent curve in it and it doesn't like to bend. If you tighten it down a certain way it won't like to bend the "wrong" way. The swivel fittings solve that problem.
I used 47" and It is a little long. If i was going to do it again I would make it shorter but just because I don't like clutter. I advise paying the extra money for swivel fittings on the line because it has a permanent curve in it and it doesn't like to bend. If you tighten it down a certain way it won't like to bend the "wrong" way. The swivel fittings solve that problem.
#26
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There is some heat shielding installed now, just need more.
#27
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Update - again
Approx 7 months and 6k miles on setup.
The eBay knockoff HKS SSQV BOV was replaced with a REAL 2007 new generation HKS SSQV BOV. Huge difference in operation. Besides the fact that the knockoff had catastrophic failure and leaked all the time, even when new, it vented at idle at full preload. I thought this was how things were supposed to work.
After installing the new HKS BOV (which has NO spring preload adjustment) there is no leak at idle. Boost comes on earlier and doesn't drop off nearly as much between shifts. It vents a LOT less than the knockoff.
Knockoff: $93 shipped
Real: $184 shipped
The BOV started leaking badly while I was playing with cam timing so the thread that I was attempting to report my results is pretty much invalid.
The most annoying part is that I have to retune.
The eBay knockoff HKS SSQV BOV was replaced with a REAL 2007 new generation HKS SSQV BOV. Huge difference in operation. Besides the fact that the knockoff had catastrophic failure and leaked all the time, even when new, it vented at idle at full preload. I thought this was how things were supposed to work.
After installing the new HKS BOV (which has NO spring preload adjustment) there is no leak at idle. Boost comes on earlier and doesn't drop off nearly as much between shifts. It vents a LOT less than the knockoff.
Knockoff: $93 shipped
Real: $184 shipped
The BOV started leaking badly while I was playing with cam timing so the thread that I was attempting to report my results is pretty much invalid.
The most annoying part is that I have to retune.
#31
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I only drove it a couple miles to test the BOV but boost comes on more linearly now. Before it would hit like a sledgehammer, probably the BOV being forced shut.
I think I saw 10psi @ 3400 in 4th, around 3900 in 2nd - things are happening fast so it's hard to say. I need to do some real datalogging, have to load some software.
Bottom line: a leaky BOV is not good and a slightly leaky BOV can really trick you.
#32
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Datalogging is still down due to usb to serial converter cable issues. This gives a better idea of how the eBay T3/T4 works. The new HKS SSQV works exceptionally well.
BTW, it's the passenger who is making the commentary, not me.
BTW, it's the passenger who is making the commentary, not me.
#34
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Thanks, I've been meaning to post a clip of the exhaust. 3" turbo back, no cat, straight through Dynomax. I think it's very quiet, at least until the WG opens.
#36
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I forgot to post about that. After deciding to not go with delrin on the rear diff mounts I found someone who attempted to get me a set of urethane bushings from Japan. Never happened. I ended up going with the Mazda Comp diff bushings. The lower steel spacer that goes between the PPF and diff housing was broken. Not sure if this was the cause or the effect.
Wheel hop is greatly reduced but not completely eliminated. It used to be really bad.
If it's really bad the next time I go to the dragstrip I might put some effort in to figuring out what's really causing the problem.
Wheel hop is greatly reduced but not completely eliminated. It used to be really bad.
If it's really bad the next time I go to the dragstrip I might put some effort in to figuring out what's really causing the problem.