Hornetball's Build
#121
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Once you wear out the Rivals, move on to stickier rubber. Hoosiers are massive overkill and unnecessary wallet poundage for yours & mine joe schmo purposes but I really like the Toyo RR's I'm running now.
#122
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Yeah, if I've learned nothing else, I've learned traction is king and the speeds on the straights (and, ultimately, laptimes) are determined by the speeds in the turns.
I also really like Rivals for double-duty DD/Track tires. Silver will keep them and revert to more of a DD car. Red, on the other hand. What's the next step up in the BFG lineup? R1? Have to stick with BFG, you know. Support Dad's retirement.
I also really like Rivals for double-duty DD/Track tires. Silver will keep them and revert to more of a DD car. Red, on the other hand. What's the next step up in the BFG lineup? R1? Have to stick with BFG, you know. Support Dad's retirement.
#123
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Two potential track cars and one driver? Tisk tisk!
Congrats on your new personal best lap time, you're looking smoother and smoother each video you upload.
The #2 cylinder sounds pretty interesting, being your problem again, which head gasket are you using Rick?
On my first NB I had a similar problem, car overheated which turned out to be the head gasket. Replaced that and a few weeks/month later it happened again. I shelled out the coin for a better gasket and had no problems til I sold it. My next problem was being addicted to the miata.
Congrats on your new personal best lap time, you're looking smoother and smoother each video you upload.
The #2 cylinder sounds pretty interesting, being your problem again, which head gasket are you using Rick?
On my first NB I had a similar problem, car overheated which turned out to be the head gasket. Replaced that and a few weeks/month later it happened again. I shelled out the coin for a better gasket and had no problems til I sold it. My next problem was being addicted to the miata.
#124
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Hey Justin. I've been trying to get ahold of you for some track time! Did you go to that course in Houston?
I'm just using an OEM composite head gasket with OEM head bolts (crate engine). I think it's time for ARP studs and a good MLS gasket. I'm focused on the Red car right now though.
I'm not sure it's the head gasket this time though. Pressurized crankcase and loss of compression with no other typical head gasket signs. Likely a broken ring or something like that. Fortunately, Donnie's right down the road. I'm thinking of just building up spare engines for both cars . . . like a race team, LOL.
I'm just using an OEM composite head gasket with OEM head bolts (crate engine). I think it's time for ARP studs and a good MLS gasket. I'm focused on the Red car right now though.
I'm not sure it's the head gasket this time though. Pressurized crankcase and loss of compression with no other typical head gasket signs. Likely a broken ring or something like that. Fortunately, Donnie's right down the road. I'm thinking of just building up spare engines for both cars . . . like a race team, LOL.
#125
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R1 is available only in 205/50 and 225/50, unfortunately. So really your only option for R1 is the 205/50 on an 8" wheel. 225/50 is going to be a tall tire. For 225/45 on 9's, your best bets are Toyo RR, Maxxis RC-1, and Nitto NT-01.
Psst - run the 205/50 Rivals on 8's as your wets, that way you still support Pop's pension while you run properly sized other rubber on your 9's as your dry tires.
Psst - run the 205/50 Rivals on 8's as your wets, that way you still support Pop's pension while you run properly sized other rubber on your 9's as your dry tires.
#126
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Yeah, I just noticed that sizing. 50 is pretty darn tall, especially on an NA.
Of course, this is all daydreaming. I have two Miatas, but neither is trackworthy at the moment. I NEED to fix this issue.
Of course, this is all daydreaming. I have two Miatas, but neither is trackworthy at the moment. I NEED to fix this issue.
#127
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Hey Justin. I've been trying to get ahold of you for some track time! Did you go to that course in Houston?
I'm just using an OEM composite head gasket with OEM head bolts (crate engine). I think it's time for ARP studs and a good MLS gasket. I'm focused on the Red car right now though.
I'm not sure it's the head gasket this time though. Pressurized crankcase and loss of compression with no other typical head gasket signs. Likely a broken ring or something like that. Fortunately, Donnie's right down the road. I'm thinking of just building up spare engines for both cars . . . like a race team, LOL.
I'm just using an OEM composite head gasket with OEM head bolts (crate engine). I think it's time for ARP studs and a good MLS gasket. I'm focused on the Red car right now though.
I'm not sure it's the head gasket this time though. Pressurized crankcase and loss of compression with no other typical head gasket signs. Likely a broken ring or something like that. Fortunately, Donnie's right down the road. I'm thinking of just building up spare engines for both cars . . . like a race team, LOL.
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Guess I had missed your compression test. Sure seems like a broken ring or either a floated valve. If you plan a rebuild I would invest in a better valve train, specially with the intentions of tracking it. MER might have a couple 99 long blocks sitting around, that's where I found mine. That would definitely be a better start than rebuilding the 1.6L
#128
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WooW insane proyect!! very impresive! ![](https://www.miataturbo.net/images/smilies/eek.gif)
Caught my attention the purge Valve Modification for AC Idle, I thought this was done with the MSPNP unmodified.
Because the official website announced this feature is already. (for MSPNP gen1). >http://i830.photobucket.com/albums/z...nout/acpnp.jpg
Or actually say in "small letters" ??? : The AC will continue to function properly (WITHOUT PROPERLY IDLE MMUUAAAAJAJAAHAHAH
)
Does not control the IAC valve or EGR?
Anyway, I'm Interested in this modification before installing my own MSPNP
But I'm scared because I see 7 wires and two diodes in the pictures and which is not the Pin J1, Pin 2x, Pin 1b, Pin 37 and 38 also the red filter connected to EGR valve is it necessary?
I'm actually a little lost and I am asking for help, maybe you can have more pictures "step by step" or any recomendation about this.
Your post it is solid and complete but it is important for me to get all the possible extra information for not to mess up 700$
![](https://www.miataturbo.net/images/smilies/eek.gif)
Caught my attention the purge Valve Modification for AC Idle, I thought this was done with the MSPNP unmodified.
Because the official website announced this feature is already. (for MSPNP gen1). >http://i830.photobucket.com/albums/z...nout/acpnp.jpg
Or actually say in "small letters" ??? : The AC will continue to function properly (WITHOUT PROPERLY IDLE MMUUAAAAJAJAAHAHAH
![Thefinger](https://www.miataturbo.net/images/smilies/thefinger.gif)
Does not control the IAC valve or EGR?
Anyway, I'm Interested in this modification before installing my own MSPNP
But I'm scared because I see 7 wires and two diodes in the pictures and which is not the Pin J1, Pin 2x, Pin 1b, Pin 37 and 38 also the red filter connected to EGR valve is it necessary?
I'm actually a little lost and I am asking for help, maybe you can have more pictures "step by step" or any recomendation about this.
Your post it is solid and complete but it is important for me to get all the possible extra information for not to mess up 700$
I implemented the Purge Valve mod on my MSPNP last week. The basic idea (another Joe Perez concoction) is to apply power to the Purge Valve when the AC compressor is engaged. This causes a vacuum leak to increase engine speed. Because this happens right away, it helps prevent RPM drop while the normal closed loop idle controls catch up. This is pretty important to me at the moment. June 2011 was, apparently, the hottest June on record since 1980. Average high temperature in my area was ~100°F with many days much hotter.
This modification can be done entirely inside the MS. The wires that are needed already exist in the stock harness. The ECU output to the AC relay is on the "L/B" line (Pin 1J on 90-93s), and the output to the Purge Valve is on the "Y/R" line (Pin 2X on 90-93s). I added a couple of diodes to my installation for safety, an isolation diode between "L/B" and "Y/R," and a flyback voltage diode from "Y/R" to ECU power on "W/R" (Pin 1B on 90-93s). Schematic is simple:
"L/B" Pin 1J---|<---"Y/R" Pin 2X--->|---"W/R" Pin1B
(where --->|--- is a 1N400X diode)
Here's a picture of my MSPNP daughter board mods:
![](https://www.miataturbo.net/attachments/build-threads-57/127608-hornetballs-build-img00258-20110703-1222.jpg?dateline=1415930894)
The two diodes go from unused header pins to the 37-pin connector at pins 28 (internally connected to ECU power on Pin 1B) and 31 (connected to Pin 1J as part of an earlier spark table switching mod). In addition, a jumper line was soldered between the unused header pins and Pin 2X.
In the engine compartment, the purge valve is disconnected from the charcoal cannister. In my case, the cannister had already been removed to make way for my WI pump. The only other change was to add a small-engine inline fuel filter to filter the air from the purge valve. Here's a picture:
![](https://www.miataturbo.net/attachments/build-threads-57/127609-hornetballs-build-img00261-20110704-1615.jpg?dateline=1415930894)
Bottom line on this modification is that it adds ~100-150RPM when activated. Most of the restriction comes from the length of rubber tube between the purge valve and the intake manifold. With different components, you could increase that RPM bump quite a bit, although at some point you would need to start worrying about boost leaks. Unlike the stock ECU, the MS doesn't disengage the AC at high throttle settings. If you're willing to hack the harness a bit, you could wire a TPS switch inline to perform that function.
Anyway, I'm pretty happy with the setup. Between the spark table switching (adds 8° of ignition advance when the AC relay activates) and this purge valve mod, my idle operation with AC on in the extreme TX heat has been pretty decent.
YMMV.
This modification can be done entirely inside the MS. The wires that are needed already exist in the stock harness. The ECU output to the AC relay is on the "L/B" line (Pin 1J on 90-93s), and the output to the Purge Valve is on the "Y/R" line (Pin 2X on 90-93s). I added a couple of diodes to my installation for safety, an isolation diode between "L/B" and "Y/R," and a flyback voltage diode from "Y/R" to ECU power on "W/R" (Pin 1B on 90-93s). Schematic is simple:
"L/B" Pin 1J---|<---"Y/R" Pin 2X--->|---"W/R" Pin1B
(where --->|--- is a 1N400X diode)
Here's a picture of my MSPNP daughter board mods:
![](https://www.miataturbo.net/attachments/build-threads-57/127608-hornetballs-build-img00258-20110703-1222.jpg?dateline=1415930894)
The two diodes go from unused header pins to the 37-pin connector at pins 28 (internally connected to ECU power on Pin 1B) and 31 (connected to Pin 1J as part of an earlier spark table switching mod). In addition, a jumper line was soldered between the unused header pins and Pin 2X.
In the engine compartment, the purge valve is disconnected from the charcoal cannister. In my case, the cannister had already been removed to make way for my WI pump. The only other change was to add a small-engine inline fuel filter to filter the air from the purge valve. Here's a picture:
![](https://www.miataturbo.net/attachments/build-threads-57/127609-hornetballs-build-img00261-20110704-1615.jpg?dateline=1415930894)
Bottom line on this modification is that it adds ~100-150RPM when activated. Most of the restriction comes from the length of rubber tube between the purge valve and the intake manifold. With different components, you could increase that RPM bump quite a bit, although at some point you would need to start worrying about boost leaks. Unlike the stock ECU, the MS doesn't disengage the AC at high throttle settings. If you're willing to hack the harness a bit, you could wire a TPS switch inline to perform that function.
Anyway, I'm pretty happy with the setup. Between the spark table switching (adds 8° of ignition advance when the AC relay activates) and this purge valve mod, my idle operation with AC on in the extreme TX heat has been pretty decent.
YMMV.
#129
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Caught my attention the purge Valve Modification for AC Idle, I thought this was done with the MSPNP unmodified.
But I'm scared because I see 7 wires and two diodes in the pictures and which is not the Pin J1, Pin 2x, Pin 1b, Pin 37 and 38 also the red filter connected to EGR valve is it necessary?
But I'm scared because I see 7 wires and two diodes in the pictures and which is not the Pin J1, Pin 2x, Pin 1b, Pin 37 and 38 also the red filter connected to EGR valve is it necessary?
The purge valve mod was originally described here:
https://www.miataturbo.net/megasquir...t-c-faq-20954/
Don't worry about all the extra wires/diodes. I've made numerous other modifications to my MSPNP. The posted description of the purge valve mod is complete. It really is that simple.
The red filter isn't necessary, but it sure doesn't hurt to filter the air going into your engine.
In the end, the purge valve mod didn't quite get me there. I would still sometimes stall when using the AC in hot weather. I then made a code hack which resolved the issue. The code hack is described here:
https://www.miataturbo.net/megasquir...de-hack-73751/
#130
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Thanks for the quick reply!
Yes I have a first Gen white cover, in fact I have already done a modification which was the variable tps.
My problem is idle dip when the compressor kicks on.
But seeing threads
and
I think it has more relevance the code hack to solve the problem with the Idle right?
Yes I have a first Gen white cover, in fact I have already done a modification which was the variable tps.
My problem is idle dip when the compressor kicks on.
But seeing threads
The code hack is described here:
https://www.miataturbo.net/megasquirt...de-hack-73751/
https://www.miataturbo.net/megasquirt...de-hack-73751/
The purge valve mod was originally described here:
https://www.miataturbo.net/megasquirt...t-c-faq-20954/
https://www.miataturbo.net/megasquirt...t-c-faq-20954/
#134
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Only problem I've had with water injection is lack of discipline on my part. It's fine for 20 minute sessions, but during a 30 minute session I run out of fluid. The warning light comes on but I ignore it because I'm having too darn much fun. After several months of doing this, I finally paid the price!
Soooo . . . dropping the fresh engine in this weekend. Adding an intercooler like I should have done in the first place (the WI does work to suppress det . . . until you run out of fluid). Now I'll have a decent intercooler (FAB9 unit) and WI. Good to go!!
Let's see which Miata is faster. Red car has set the bar at 1:25.191 and has a NASA TTD Track Record to its credit. Silver car would probably class TTC or TTB.
Soooo . . . dropping the fresh engine in this weekend. Adding an intercooler like I should have done in the first place (the WI does work to suppress det . . . until you run out of fluid). Now I'll have a decent intercooler (FAB9 unit) and WI. Good to go!!
Let's see which Miata is faster. Red car has set the bar at 1:25.191 and has a NASA TTD Track Record to its credit. Silver car would probably class TTC or TTB.
Last edited by hornetball; 03-19-2015 at 04:17 PM.
#136
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Yes. See post #120 (https://www.miataturbo.net/build-thr...6/#post1113926). I've been having so much fun with the Red car that it's been sitting. But it's time to bring it back to life!
#137
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Only problem I've had with water injection is lack of discipline on my part. It's fine for 20 minute sessions, but during a 30 minute session I run out of fluid. The warning light comes on but I ignore it because I'm having too darn much fun. After several months of doing this, I finally paid the price!
Soooo . . . dropping the fresh engine in this weekend. Adding an intercooler like I should have done in the first place (the WI does work to suppress det . . . until you run out of fluid). Now I'll have a decent intercooler (FAB9 unit) and WI. Good to go!!
Let's see which Miata is faster. Red car has set the bar at 1:25.191 and has a NASA TTD Track Record to its credit. Silver car would probably class TTC or TTB.
Soooo . . . dropping the fresh engine in this weekend. Adding an intercooler like I should have done in the first place (the WI does work to suppress det . . . until you run out of fluid). Now I'll have a decent intercooler (FAB9 unit) and WI. Good to go!!
Let's see which Miata is faster. Red car has set the bar at 1:25.191 and has a NASA TTD Track Record to its credit. Silver car would probably class TTC or TTB.
#138
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Your 5 gallon tank will let you run a long time on track. That's a ton of capacity!
#139
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This is mostly a street car, and on the street the washer tank provides plenty of capacity. I'm planning to install and tune for my intercooler and just use the WI as additional protection. I'm tight under the hood and want to keep what trunk space I have.
Your 5 gallon tank will let you run a long time on track. That's a ton of capacity!
Your 5 gallon tank will let you run a long time on track. That's a ton of capacity!