Honcho's Long Road to Imola Type-S Zero
- Thread starter Honcho
- Start date
Snow Day
A rare (these days) storm dumped 24 inches of snow on us over the last 2 days. So, the NSX is taking a break and having some nice battery conditioning. I also blew out the gear case on my snowblower after hitting an ice chunk so I'll be rebuilding it in the garage today...
A rare (these days) storm dumped 24 inches of snow on us over the last 2 days. So, the NSX is taking a break and having some nice battery conditioning. I also blew out the gear case on my snowblower after hitting an ice chunk so I'll be rebuilding it in the garage today...
ATR Side Scoops
Prior to NSXPO, I began work prepping the ATR side scoops for the car. As you may recall, the Route KS scoops fit like garbage and I've been eager to replace them with a far superior part. Christian makes these in a true dry carbon layup and they are incredibly light. I had my painter Mike prep and paint them and they turned out fantastic, as usual with him. However, these scoops ship without any grill, so I had to fabricate one. The factory scoops use a bolt-on mesh encased in a plastic frame. I chose a black-coated aluminum mesh, since I could bend the aluminum to fit the complex shape of the scoop.
After cutting out the basic shape, I carefully cut, bent and folded the piece around the scoop until it sat perfectly in position without any tension.
The result was a perfectly-fitted mesh!
Next, I used some JB Weld to glue the mesh into place. It worked very well and is quite strong.
The result looks like factory.
I had to stop here because I misplaced the side scoop mounting bolts. The ATR scoop does not ship with the studs and you must re-use them from your old scoops. I couldn't remember if I used them on the Route KS scoops or not and didn't want to take the chance only a few days before the trip to NSXPO. A new set of bolts are on their way from Japan along with some other key items, so I'll pick this project back up in a few weeks.
Prior to NSXPO, I began work prepping the ATR side scoops for the car. As you may recall, the Route KS scoops fit like garbage and I've been eager to replace them with a far superior part. Christian makes these in a true dry carbon layup and they are incredibly light. I had my painter Mike prep and paint them and they turned out fantastic, as usual with him. However, these scoops ship without any grill, so I had to fabricate one. The factory scoops use a bolt-on mesh encased in a plastic frame. I chose a black-coated aluminum mesh, since I could bend the aluminum to fit the complex shape of the scoop.
After cutting out the basic shape, I carefully cut, bent and folded the piece around the scoop until it sat perfectly in position without any tension.
The result was a perfectly-fitted mesh!
Next, I used some JB Weld to glue the mesh into place. It worked very well and is quite strong.
The result looks like factory.
I had to stop here because I misplaced the side scoop mounting bolts. The ATR scoop does not ship with the studs and you must re-use them from your old scoops. I couldn't remember if I used them on the Route KS scoops or not and didn't want to take the chance only a few days before the trip to NSXPO. A new set of bolts are on their way from Japan along with some other key items, so I'll pick this project back up in a few weeks.
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Weight Reduction
One thing I have been tracking since the beginning of the project is my weight reduction effort. I've been inspired over the years by epic threads from old school Prime members. Those guys went all the way, removing their windshield wipers, replacing the windows with Lexan, and even swapping carbon door panels (and doors!) My goal was instead to get my car close to the S-Zero "official" weight of 1,270 kg or 2,799 lbs.
As mentioned previously in the blog, there are things on the genuine S-Zero that I can't replicate on my 1992 NSX like the lighter 97+ body panels and trim-specific wire harnesses that delete several pounds of unnecessary wire. My plan was to find those weight savings elsewhere, like in the CF body parts. I built my spreadsheet when I was still thinking of the project in "stages." Stage 0 was what I considered to be the "easy" mods- either things I could remove from the car or easy parts to fit. As you can see, Stage 0 nets almost exactly 200 lbs of weight savings over a stock 1992 AT NSX. The car sits at about 2,900 lbs in that configuration, or about the weight of a genuine NSX Type-S. Key reductions were the spare tire, tool kit, EPS, and suspension (the MCS is astoundingly lighter). Green is weight removed and red is weight added.
After the "easy" stuff, weight becomes harder to find. "Stage 1" involved replacing the bumper beams, swapping the B-pillars and side scoops for carbon fiber versions, changing exhaust, battery and ABS, and swapping the heavy factory seats for the racing shells. At this stage, I exceeded my goal: 2,766 lbs.
The final form is "Stage 2," which includes the most expensive and difficult modifications: MT swap, headers, fluwheel and the rear glass, which is not yet completed. Before the glass, the car sits at 2,655 lbs in its current state. My sense is the glass will net a few more pounds, putting me right around 2,645 lbs or 1,200 kg.
Finally, inspired by @blaketjones, I graphed out some of the performance metrics for the various stages:
Assuming my engine tuning comes in around 330 crank hp, I'm very close to a 996.1 GT3, which is really, really nice.
One thing I have been tracking since the beginning of the project is my weight reduction effort. I've been inspired over the years by epic threads from old school Prime members. Those guys went all the way, removing their windshield wipers, replacing the windows with Lexan, and even swapping carbon door panels (and doors!) My goal was instead to get my car close to the S-Zero "official" weight of 1,270 kg or 2,799 lbs.
As mentioned previously in the blog, there are things on the genuine S-Zero that I can't replicate on my 1992 NSX like the lighter 97+ body panels and trim-specific wire harnesses that delete several pounds of unnecessary wire. My plan was to find those weight savings elsewhere, like in the CF body parts. I built my spreadsheet when I was still thinking of the project in "stages." Stage 0 was what I considered to be the "easy" mods- either things I could remove from the car or easy parts to fit. As you can see, Stage 0 nets almost exactly 200 lbs of weight savings over a stock 1992 AT NSX. The car sits at about 2,900 lbs in that configuration, or about the weight of a genuine NSX Type-S. Key reductions were the spare tire, tool kit, EPS, and suspension (the MCS is astoundingly lighter). Green is weight removed and red is weight added.
After the "easy" stuff, weight becomes harder to find. "Stage 1" involved replacing the bumper beams, swapping the B-pillars and side scoops for carbon fiber versions, changing exhaust, battery and ABS, and swapping the heavy factory seats for the racing shells. At this stage, I exceeded my goal: 2,766 lbs.
The final form is "Stage 2," which includes the most expensive and difficult modifications: MT swap, headers, fluwheel and the rear glass, which is not yet completed. Before the glass, the car sits at 2,655 lbs in its current state. My sense is the glass will net a few more pounds, putting me right around 2,645 lbs or 1,200 kg.
Finally, inspired by @blaketjones, I graphed out some of the performance metrics for the various stages:
Assuming my engine tuning comes in around 330 crank hp, I'm very close to a 996.1 GT3, which is really, really nice.
Reading this bums me out Honcho especially since I was one of the said judges in question. Seeing that you dedicated 163 word paragraph to the subject shows that you do obviously care so I'll go ahead and explain everything from our side of things.
My father (Matt) and I (Trent) were put in charge of the concourse awards back at the 2022 AZ NSXPO and we made sure that the judging was fair, accurate, and that the judges brought in were respective experts on the categories they put in charge of. As such, we were asked to judge this NSXPO as well but we were not in charge of picking what categories existed. Because of this, we had these to work with:
-Best Stock/Modified first gen
-Best Stock/Modified second gen (NC1)
-Best interior
-Best engine bay
-two peoples choice
-John Vasos
This NSXPO also had the highest number of NSXs in attendance ever from what I heard and as such, we had a very high number of quality cars and builds at the concourse...which I know you can attest to. Now to break it down, your car fell into the modified first gen category which immediately places you into competition with people such as Joel Zabel, Mike Tran, Wayne Cordon, Akbar Mirza, etc...which I'm sure I don't need to impress upon you have some of cleanest and best builds in the country.
But to come onto here and suggest that the judges "just saw an orange NSX and were like 'cool' and moved on to the next car" is a flat out insult to not only myself (who actually saw the car in person being built a number of times in your own garage) but to the other judges as well. I was easily able to explain who you were, the idea behind the build, where it started, etc...only to find out that all the judges know you and the build as well and follow it on here too.
I'm not on here to bash your car, the build or anything regarding your car because I love the build, I genuinely do. I spent a decent amount of time admiring it at NSXPO since it was the first time I'd seen it together. I only take issue when you imply we don't know what we're looking at when we know EXACTLY what we were looking at....that also happens to fall in the MOST competitive category of the concourse awards.
I've enjoyed following the build, I will continue to do so and if you decide that you do care after all, I'd be happy to talk to you about the show and why your car placed where it did.
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@streeter no harm meant at all, seriously. I loved the car show and didn't even realize my car was being entered until someone handed me a number. I was a concours judge for years and believe me- I get it. It's a thankless job and you mostly make everyone mad and about 4 people really happy! For the record, I think you and your dad did a fantastic job and the cars that won definitely deserved it. They were way cooler than my dumb little project here. I spent most of the car show admiring them. I was trying to explain my observation that oftentimes the time, effort and love we put into our cars doesn't translate at a car show. To us, it's a treasure, but at a show like NSXPO, there are a hundred treasures there. And the judges only get to spend a few minutes with each one at best. That's the point I was trying to make to my son- I came to the event to see old friends, meet new ones and spend time with NSX people like me. Trophies are nice, but it's not why I did this. I didn't mean at all to impugn you or the other judges. I'll edit the post to reflect that.
Annual Service
Compression Test - Health Check
After the long drive home from Texas, it was time for the annual service. I took advantage of the long cruise so the hot Mobil 1 oil would perform a good clean on the engine internals. This year, the Zero covered 2,974 miles in between oil changes, which is a lot for this car. Over half those miles were on the NSXPO trip, so lots of highway cruising.
I fired up the car and took a 30 minute highway trip with my son as a very eager passenger. We were running with a powder blue Ferrari 488 for a while and he was so excited. When he asked if the Zero was as fast as the F car, I just laughed. Once home, he helped me with the compression test. In 2019, pre-refresh, the car tested quite healthy:
#1 --> 191 psi (229 @ sea level)
#2 --> 191 psi (229)
#3 --> 190 psi (228)
#4 --> 192 psi (230)
#5 --> 190 psi (228)
#6 --> 192 psi (230)
Here, we have the post-refresh results:
#1 --> 195 psi (234)
#2 --> 195 psi (234)
#3 --> 194 psi (233)
#4 --> 196 psi (235)
#5 --> 198 psi (238)
#6 --> 199 psi (239)
This is a significant improvement. All cylinders improved over the last test. I believe its a combination of the valve adjustment and tighter clearances from the head rebuild. There is only 6 psi of variance between the cylinders and number 5 and 6 are essentially showing brand-new spec at 140,000 miles. The build quality of this engine is simply astounding. We'll never see engineering like this again. Interestingly, the increase on 1 - 4 followed the same shape, where the refresh made larger improvements to 5 and 6. I can only speculate that the ring seal might be better on 5 and 6. Another way to look at the data is that the front bank is stronger than the rear bank. I wonder if this shape will continue year to year?
Coils and Spark Plugs Removed
Testing in progress. I remove the rear strut brace for easy access.
Placing rags over the spark plug holes to protect from debris. I never put plugs back into a hot engine. I wait overnight until it's fully cold.
I strongly encourage owners that DIY their oil changes to add the compression test to their annual service. It's not hard to do and is a great way to keep track of the health of your NSX's engine. Often you can spot issues before they become big problems.
Compression Test - Health Check
After the long drive home from Texas, it was time for the annual service. I took advantage of the long cruise so the hot Mobil 1 oil would perform a good clean on the engine internals. This year, the Zero covered 2,974 miles in between oil changes, which is a lot for this car. Over half those miles were on the NSXPO trip, so lots of highway cruising.
I fired up the car and took a 30 minute highway trip with my son as a very eager passenger. We were running with a powder blue Ferrari 488 for a while and he was so excited. When he asked if the Zero was as fast as the F car, I just laughed. Once home, he helped me with the compression test. In 2019, pre-refresh, the car tested quite healthy:
#1 --> 191 psi (229 @ sea level)
#2 --> 191 psi (229)
#3 --> 190 psi (228)
#4 --> 192 psi (230)
#5 --> 190 psi (228)
#6 --> 192 psi (230)
Here, we have the post-refresh results:
#1 --> 195 psi (234)
#2 --> 195 psi (234)
#3 --> 194 psi (233)
#4 --> 196 psi (235)
#5 --> 198 psi (238)
#6 --> 199 psi (239)
This is a significant improvement. All cylinders improved over the last test. I believe its a combination of the valve adjustment and tighter clearances from the head rebuild. There is only 6 psi of variance between the cylinders and number 5 and 6 are essentially showing brand-new spec at 140,000 miles. The build quality of this engine is simply astounding. We'll never see engineering like this again. Interestingly, the increase on 1 - 4 followed the same shape, where the refresh made larger improvements to 5 and 6. I can only speculate that the ring seal might be better on 5 and 6. Another way to look at the data is that the front bank is stronger than the rear bank. I wonder if this shape will continue year to year?
Coils and Spark Plugs Removed
Testing in progress. I remove the rear strut brace for easy access.
Placing rags over the spark plug holes to protect from debris. I never put plugs back into a hot engine. I wait overnight until it's fully cold.
I strongly encourage owners that DIY their oil changes to add the compression test to their annual service. It's not hard to do and is a great way to keep track of the health of your NSX's engine. Often you can spot issues before they become big problems.
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Annual Service 2
Oil Change and Oil Sample
Moving to the oil change, I had the occasion to use the very nice oil filter drain guard that @Wild Turkey was kind enough to make for me. He even printed it in the car's colors- cool!
Here it is in place - fits perfectly.
A care package arrived from Japan. Many OEM parts for the hoard. I will cover that in a later post.
These are the new light blue (-306) Mahle OEM oil filters, made in Thailand. They appear to be of the same quality as the old Filtech dark blue units. Since my oil change interval is 3,000 miles or less, I don't believe that the tall filters are necessary.
All of the materials ready. I had two of the "old" 0W-40 formulation left from the last oil change. This is the API SN formula. Recently, Mobil updated the FS 0W-40 to the API SP formula. Supposedly they reduced calcium in the add package to hit the SP requirements, which is apparently a benefit for GTDI engines and specifically timing chain wear on those engines. I'll be interested to see if it shows up in the UOA. Don't forget the crush washer!
Old Mobil 1 drained out. It looked and smelled clean. Still had the honey color.
Tim's drain guard worked great!
Sample kit ready to go.
The car took exactly 5 quarts and about 100 ml. Tomorrow, I will install the spark plugs and coils and warm up the engine to check the level again.
Oil Change and Oil Sample
Moving to the oil change, I had the occasion to use the very nice oil filter drain guard that @Wild Turkey was kind enough to make for me. He even printed it in the car's colors- cool!
Here it is in place - fits perfectly.
A care package arrived from Japan. Many OEM parts for the hoard. I will cover that in a later post.
These are the new light blue (-306) Mahle OEM oil filters, made in Thailand. They appear to be of the same quality as the old Filtech dark blue units. Since my oil change interval is 3,000 miles or less, I don't believe that the tall filters are necessary.
All of the materials ready. I had two of the "old" 0W-40 formulation left from the last oil change. This is the API SN formula. Recently, Mobil updated the FS 0W-40 to the API SP formula. Supposedly they reduced calcium in the add package to hit the SP requirements, which is apparently a benefit for GTDI engines and specifically timing chain wear on those engines. I'll be interested to see if it shows up in the UOA. Don't forget the crush washer!
Old Mobil 1 drained out. It looked and smelled clean. Still had the honey color.
Tim's drain guard worked great!
Sample kit ready to go.
The car took exactly 5 quarts and about 100 ml. Tomorrow, I will install the spark plugs and coils and warm up the engine to check the level again.
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Annual Service 3
VVIS Inspection
Annual service is also a good time for the VVIS inspection. Although it seems some NSX engines are totally fine, there's no way to know if you will be affected. Thus, it's a good idea to keep an eye on these screws. I disagree with others in that I believe the VVIS system is worthwhile on a stock or NA NSX, as it has been repeatedly shown to add about 10 lb/ft of torque under the curve in the mid range. Torque on this car is at a premium, so I'm keeping my VVIS!
During the refresh, I checked the screws and they had not moved. The swages appeared to be holding. I elected not to disturb them.
For this service, you need to remove the top of the airbox.
Cylinder number 1 all in place.
Cylinder number 2 looking good. I kind of wish I took the time to brush off all that gray plate edge sealant- you can see it gunked in there. I was afraid to disturb the system, but @MotorMouth93 did it and his VVIS look amazing!
Cylinder number 3 all in place.
Cylinder number 4 looks fine.
Same with number 5.
Finally, number 6 is all good.
I can rest easy for another year. Job done.
VVIS Inspection
Annual service is also a good time for the VVIS inspection. Although it seems some NSX engines are totally fine, there's no way to know if you will be affected. Thus, it's a good idea to keep an eye on these screws. I disagree with others in that I believe the VVIS system is worthwhile on a stock or NA NSX, as it has been repeatedly shown to add about 10 lb/ft of torque under the curve in the mid range. Torque on this car is at a premium, so I'm keeping my VVIS!
During the refresh, I checked the screws and they had not moved. The swages appeared to be holding. I elected not to disturb them.
For this service, you need to remove the top of the airbox.
Cylinder number 1 all in place.
Cylinder number 2 looking good. I kind of wish I took the time to brush off all that gray plate edge sealant- you can see it gunked in there. I was afraid to disturb the system, but @MotorMouth93 did it and his VVIS look amazing!
Cylinder number 3 all in place.
Cylinder number 4 looks fine.
Same with number 5.
Finally, number 6 is all good.
I can rest easy for another year. Job done.
Annual Service 4
Spark Plugs
These are the OEM Denso PK20PR-L11 Double Platinum spark plugs. Slightly less expensive than the NGK version. The camera did not pick up the colors correctly (looks almost black), but after about 3,700 miles, the plugs looked almost new as expected. You could still see the shine of the metal on the ground electrode under a very light tan color- you can see this best on Number 6. Overall, this means that the engine tuning is quite good and delivering a proper mixture.
Plugs are returned to the engine with a light coat of antisieze. I torque to 13 lb/ft with this combination. They always come out easy. Next up are the ignition coils. I always make sure to use some Dow Corning #4 dielectric grease at the boot tip and the upper coil seal. It helps keep water completely isolated from the spark plug.
After installing the coils, it's the usual struggle with the rear coil cover and rubber seal. Using some more of the DC grease helps hold the seal in place. After inspecting my ignition coils, I'm starting to become concerned about how much life these 32-year old components have left in them. They run perfectly fine, but I am beginning to think it may be worthwhile to change to the K-Series coil. It's a far more modern and robust system, and I have the ability to adjust coil dwell in the Demon. I'm looking at 3D printing some kind of bracket to hold the coils in place and using the factory bolt holes in the valve cover.
Once everything is torqued down, re-installed the fuel injector resistor plug and fired up the car. Of course, it fired on the first half crank as normal. It was interesting to see the oil pressure fault light flash for a split second as the new oil rushed past the sensor to pressurize the system. Good to know that circuit is functioning properly. Warmed up the car and revved to 6,000 rpm. Smooth as glass. The NSX is ready for the next year.
Spark Plugs
These are the OEM Denso PK20PR-L11 Double Platinum spark plugs. Slightly less expensive than the NGK version. The camera did not pick up the colors correctly (looks almost black), but after about 3,700 miles, the plugs looked almost new as expected. You could still see the shine of the metal on the ground electrode under a very light tan color- you can see this best on Number 6. Overall, this means that the engine tuning is quite good and delivering a proper mixture.
Plugs are returned to the engine with a light coat of antisieze. I torque to 13 lb/ft with this combination. They always come out easy. Next up are the ignition coils. I always make sure to use some Dow Corning #4 dielectric grease at the boot tip and the upper coil seal. It helps keep water completely isolated from the spark plug.
After installing the coils, it's the usual struggle with the rear coil cover and rubber seal. Using some more of the DC grease helps hold the seal in place. After inspecting my ignition coils, I'm starting to become concerned about how much life these 32-year old components have left in them. They run perfectly fine, but I am beginning to think it may be worthwhile to change to the K-Series coil. It's a far more modern and robust system, and I have the ability to adjust coil dwell in the Demon. I'm looking at 3D printing some kind of bracket to hold the coils in place and using the factory bolt holes in the valve cover.
Once everything is torqued down, re-installed the fuel injector resistor plug and fired up the car. Of course, it fired on the first half crank as normal. It was interesting to see the oil pressure fault light flash for a split second as the new oil rushed past the sensor to pressurize the system. Good to know that circuit is functioning properly. Warmed up the car and revved to 6,000 rpm. Smooth as glass. The NSX is ready for the next year.
Awesome! I will add VVIS to my annual winter storage as well.
Re: oil light flashing. Do you pre-fill the new oil filter when installing it? I found the oil pressure comes up faster on that 1st start after the oil change when I did that so I've been doing it ever since. But I've only changed my NSX oil 6 times so maybe it's just my impression of eliminating the time refilling the filter.
Re: oil light flashing. Do you pre-fill the new oil filter when installing it? I found the oil pressure comes up faster on that 1st start after the oil change when I did that so I've been doing it ever since. But I've only changed my NSX oil 6 times so maybe it's just my impression of eliminating the time refilling the filter.
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I don't pre-fill the filter, mostly because I'm afraid of spilling and making a mess during install LOL! To me, the extra 100 milliseconds of time you gain is not really necessary, especially if you are using synthetic oil. Even when the oil is drained for the change service, there is still a nice coat of synth oil on your bearings and cam journals, so it's not like there will be any metal-to-metal contact. If the car sits for 6 months, then perhaps it would help... maybe?
