I'll be testing different bellmouth designs and people who use this kit will have options as well but I doubt sitting below the OE cover will yield the best results. maybe! We don't know until we test it.
RYU's "properly molested" NSX build thread
- Thread starter RYU
- Start date
2 updates in one day... what has come over me!
Well... I wanted to share some photos of the RFY headers after getting ceramic coated at http://www.xtremeperformanceheatcoatings.com/. I can't say they look different than what I expected. They look good to me! Time will tell how they hold up.
btw... anyone know how much time I should budget to do a header swap in my garage? I've avoided doing this type of labor for years but why not... I know the front motor mount crossmember brace has to come out, yes?
https://www.youtube.com/watch?v=piilN0-ekv4
These turned out pretty great too. I hope the finish doesn't tarnish over time. I'm sure this will turn black as I fine tune my fuel tables...
Funny story...
Me: Hey Alan, Can I use that cardboard box over there? (Points to box to put all the loose parts into)
Alan: Sure.
Me: (see's HAAS logo) HAAS, like F1 team HAAS?
Alan: Oh yea, they're down the street. We do work them all the time.
Me: (I nodded as if that was a normal thing)
That's so cool.
Well... I wanted to share some photos of the RFY headers after getting ceramic coated at http://www.xtremeperformanceheatcoatings.com/. I can't say they look different than what I expected. They look good to me! Time will tell how they hold up.
btw... anyone know how much time I should budget to do a header swap in my garage? I've avoided doing this type of labor for years but why not... I know the front motor mount crossmember brace has to come out, yes?
https://www.youtube.com/watch?v=piilN0-ekv4
These turned out pretty great too. I hope the finish doesn't tarnish over time. I'm sure this will turn black as I fine tune my fuel tables...
Funny story...
Me: Hey Alan, Can I use that cardboard box over there? (Points to box to put all the loose parts into)
Alan: Sure.
Me: (see's HAAS logo) HAAS, like F1 team HAAS?
Alan: Oh yea, they're down the street. We do work them all the time.
Me: (I nodded as if that was a normal thing)
That's so cool.
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You're on fire! RFY manifolds are just beautiful.
It was mentioned to me no one can see the photos. I'll see what I can do to fix that
Update: Photos fixed!!! (I think)
Update: Photos fixed!!! (I think)
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I decided to tackle the header install myself. I'm starting to think this was a mistake. What a PITA especially when done on my back. For years everyone always said that front motor mount bolt is a huge PITA. I stopped 5hrs in and called it a day. I'll see if i'm willing to tackle it again today or just button it back up and put it on HQ Engineering's lift.
Being under there for so long did allow me to go over a many of the accessible nuts and bolts. I was shocked to find all of my oil pan bolts were loose. No leaks so the Hondabond must be holding but definitely many of them could be loosened by hand. Is that a common thing? I've never read of this from other owners.
btw... No pics worth posting on this post.
EDIT: [MENTION=4388]Barn Man[/MENTION] set me straight. Apparently rather common on the oil pan bolts. Check those folks!!!
Being under there for so long did allow me to go over a many of the accessible nuts and bolts. I was shocked to find all of my oil pan bolts were loose. No leaks so the Hondabond must be holding but definitely many of them could be loosened by hand. Is that a common thing? I've never read of this from other owners.
btw... No pics worth posting on this post.
EDIT: [MENTION=4388]Barn Man[/MENTION] set me straight. Apparently rather common on the oil pan bolts. Check those folks!!!
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On jacks I can see how the headers wouldn't be fun. A tip I read somewhere said to grease up the backside of the front motor mount nut to stick it to the front beam so that you have an extra hand to help you align the bolt and beam, and make sure the metal tab on the mount nut is aligned with the hole in the beam. Use a really tacky grease or something like butyl rope, just a thought. If you have someone willing to lend a hand it might work better.
What you can try as well is pre-threading the mount bolt to the nut with the beam on the ground, and then lifting the beam with the mount into position and installing the 3 mount bolts to the engine/trans. It might be tight with the header design but you should be able to torque the bolts with an open end or ratcheting wrench. The front mount through-bolt is the first one to torque in the mount installation sequence (which you might consider doing but probably not needed).
There's an oil pan leak discussion thread in DIY where Honcho & Old Guy suggested using blue threadlocker on the oil pan bolts, that's what I did recently. You could remove the bolts one at a time, clean them off, apply threadlocker, and reinstall in the factory sequence at slightly lower torque setting. I doubt you would cause more issues doing that since the bolts weren't tight anyways.
Pics work now : )
What you can try as well is pre-threading the mount bolt to the nut with the beam on the ground, and then lifting the beam with the mount into position and installing the 3 mount bolts to the engine/trans. It might be tight with the header design but you should be able to torque the bolts with an open end or ratcheting wrench. The front mount through-bolt is the first one to torque in the mount installation sequence (which you might consider doing but probably not needed).
There's an oil pan leak discussion thread in DIY where Honcho & Old Guy suggested using blue threadlocker on the oil pan bolts, that's what I did recently. You could remove the bolts one at a time, clean them off, apply threadlocker, and reinstall in the factory sequence at slightly lower torque setting. I doubt you would cause more issues doing that since the bolts weren't tight anyways.
Pics work now : )
So this header swap is turning out to be a multi-day project. Partly because i'm spending only a few hours a day on it, but i'm also giving the engine compartment a once over look-see. I already found my oil pan bolts loose and one of the main starter bolts loose. Thank goodness I haven't found anything else being loose but i'm not quite done with my review yet. Removing that crossmember was such a bitch but with the right combination of swivels and extensions I managed to get to it. There is now a dab of JB weld curing on that bolt as many have suggested. Thanks @Big McLargeHuge! Actually, previous techs who've worked on my car have done the same. There is clearly at least 2 types of adhesives/epoxies I can discern on that bolt already.
I'm also waiting on parts to come in. I'm redoing the gold shielding on my oil pan for example.
Here's a quick cellphone video I did comparing the Comptech headers vs. the RF Yamamoto. Perhaps some of you might find it interesting.
https://youtu.be/zJiE0_G98F4
P.S. In case anyone is wondering what are the general steps to remove headers. Here are mine in no particular order. Get the car high enough but doesn't have to be high enough to remove the gas tank, in case you have experience removing the gas tank (I do).
1. Remove the bottom trapezoid brace thingy. The thin big one that ties the left and right suspension ends to the center bulkhead/crossmember thingy (i'm so bad with names)
2. Remove the front crossmember that the front engine mount is attached to (you'll learn some new curse words in different languages you didn't think you knew)
2.5 Grab a beer or a hard drink
3. Disconnect both cats and O2 sensors. Maybe this is really step 1
4. Disconnect the rear sway bar mounting brackets
5. Disconnect the vertical triangle brace that's right behind the rear bank headers
6. Remove the shift cable mount housing
I'm also waiting on parts to come in. I'm redoing the gold shielding on my oil pan for example.
Here's a quick cellphone video I did comparing the Comptech headers vs. the RF Yamamoto. Perhaps some of you might find it interesting.
https://youtu.be/zJiE0_G98F4
P.S. In case anyone is wondering what are the general steps to remove headers. Here are mine in no particular order. Get the car high enough but doesn't have to be high enough to remove the gas tank, in case you have experience removing the gas tank (I do).
1. Remove the bottom trapezoid brace thingy. The thin big one that ties the left and right suspension ends to the center bulkhead/crossmember thingy (i'm so bad with names)
2. Remove the front crossmember that the front engine mount is attached to (you'll learn some new curse words in different languages you didn't think you knew)
2.5 Grab a beer or a hard drink
3. Disconnect both cats and O2 sensors. Maybe this is really step 1
4. Disconnect the rear sway bar mounting brackets
5. Disconnect the vertical triangle brace that's right behind the rear bank headers
6. Remove the shift cable mount housing
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Interesting to hear about loose bolts & nuts.
On my Alfa Romeo 4C, Alfa Romeo requires a bolt tightening service every 12K miles, where every bolt needs to be re-tightened to factory spec. I wonder if NSXs can benefit from such services over time.
On my Alfa Romeo 4C, Alfa Romeo requires a bolt tightening service every 12K miles, where every bolt needs to be re-tightened to factory spec. I wonder if NSXs can benefit from such services over time.
I moved 4yrs ago to a much smaller garage (thinking I wouldn't be working on my car as much anymore) and I've also been tracking my car much less. So I haven't had a chance to really go over her the last few years. I'm happy to report I found no new loose bolts. Granted there were a few I could not access. It might help to know... the rest of the nuts and bolts were tight.
Spent another few hours on the car today. Working from home is good for the NSX it seems. Could someone lmk if the pics don't show up again?
Redid the 7 year old gold heat shielding. the newer stuff appears to be better but I still can't get the shape to lay down nicer.
The more I handle these headers the more i'm impressed with the fitment, quality, and the ceramic coating as well.
Throughout the years there's something quite underappreciated in regards to NSX exhaust systems. Good quality parts ensure everything just fits properly.
- RF Yamamoto Exh Manifolds
- SOS street cats
- Comptech V2 muffler
So far fitment is great (these tips are going away soon)
There's a light bead of JB Weld holding this bolt in place. IT WAS SO MUCH EASIER. You can see.. battlescars from other techs all around.
Redid the 7 year old gold heat shielding. the newer stuff appears to be better but I still can't get the shape to lay down nicer.
The more I handle these headers the more i'm impressed with the fitment, quality, and the ceramic coating as well.
Throughout the years there's something quite underappreciated in regards to NSX exhaust systems. Good quality parts ensure everything just fits properly.
- RF Yamamoto Exh Manifolds
- SOS street cats
- Comptech V2 muffler
So far fitment is great (these tips are going away soon)
There's a light bead of JB Weld holding this bolt in place. IT WAS SO MUCH EASIER. You can see.. battlescars from other techs all around.
Pics all work. The Reflect-A-Gold is exactly how mine looks, it's hard to get it to stick without creases especially around the curved parts. I think you'd have to cut it into small strips to reduce the creasing, but hey, technically the air gap decreases the heat transfer rate which is actually a benefit 
.
I'd looooove to get a set of those headers, the price is just so high, justifiably so. I thought that pairing all the Pride exhaust products (headers, test pipes, muffler) would ensure good fitment but I had to pay a fabricator to fix the exhaust alignment and it's still not perfect, so definitely a cliche "you get what you pay for".
Come to think of it, the /DRIVE video you were featured in was one of the first NSX vids I watched before I got my car even though it was made 5 whole-ass years ago
. Still inspiring today. I definitely agree that the more you mess with the original Honda engineering the more you mess up lol, even if much of the stuff I've done so far is OEM-sourced. Thanks for still being active 5 years later when a noob like me joins on.
. I'd looooove to get a set of those headers, the price is just so high, justifiably so. I thought that pairing all the Pride exhaust products (headers, test pipes, muffler) would ensure good fitment but I had to pay a fabricator to fix the exhaust alignment and it's still not perfect, so definitely a cliche "you get what you pay for".
Come to think of it, the /DRIVE video you were featured in was one of the first NSX vids I watched before I got my car even though it was made 5 whole-ass years ago
. Still inspiring today. I definitely agree that the more you mess with the original Honda engineering the more you mess up lol, even if much of the stuff I've done so far is OEM-sourced. Thanks for still being active 5 years later when a noob like me joins on.
Man... you're the 2nd person that's mentioned the Drive video this week. I had forgotten it was on my signature! I had a lot of fun participating in that filming. It seems a lot has changed with Youtube videos these days.Pics all work. The Reflect-A-Gold is exactly how mine looks, it's hard to get it to stick without creases especially around the curved parts. I think you'd have to cut it into small strips to reduce the creasing, but hey, technically the air gap decreases the heat transfer rate which is actually a benefit
I'd looooove to get a set of those headers, the price is just so high, justifiably so. I thought that pairing all the Pride exhaust products (headers, test pipes, muffler) would ensure good fitment but I had to pay a fabricator to fix the exhaust alignment and it's still not perfect, so definitely a cliche "you get what you pay for".
Come to think of it, the /DRIVE video you were featured in was one of the first NSX vids I watched before I got my car even though it was made 5 whole-ass years ago
I was asked by a few folks to ask if a Group Buy is available for the headers (gosh, wish I would have thought of that when I bought mine!!! lol). I've asked Yamamoto-san and waiting for him to get back to me. Yes, agree... they're pretty pricey.
That is an excellent idea!!! I did look at that but the finish on the compressor didn't look like it would promote good adhesion. I'll give it a try and report back! I would have to take it all apart again though but having done it once it's not a big deal. Though I suppose I don't drive it hard with the AC on. Will report back!
Edit: I took a look under there just now. Even with everything apart there's no good way to wrap the compressor properly. Right below Cyl #4 has very little space and from under the car it's a super awkward position. I fear I won't do a proper job and the foil paper might come loose and come into contact with the headers (possible fire?). The back of the compressor is easy enough to wrap but I think i'll wait until I have the 3.5L engine ready. I have a note to address this before that motor goes in. Thanks again for the idea! I'll have my fabricator come up with a heat shield of some type.
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I printed a variation to the bellmouth. I have a feeling i'll be printing the final versions in ABS or some type of printable CF. Added 5* deg of tilt and incorporate some design concepts from the PDF I posted earlier. If the dyno numbers look decent for something like this i'm moving straight to the airbox design.
FYI: These look a bit shitty because I printed with no supports and as fast as possible for fitment confirmation. I'm actually very surprised the edges didn't fall off during the print. It was choosing between a 3hr print vs. a 9hr print
FYI: These look a bit shitty because I printed with no supports and as fast as possible for fitment confirmation. I'm actually very surprised the edges didn't fall off during the print. It was choosing between a 3hr print vs. a 9hr print
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RYU said:
Sheer awesomeness.
RYU said:
Standard practice is to wrap the header pipe closest to the compressor face and cover the compressor with the heat reflective foil. Kaz does it, and so does Mr. Toyoizumi at T3TEC. Helps preserve the life of your compressor.
http://www.nsxcb.co.uk/entry.php?1839-AC-Refresh-04&goto=next
I'm printing 2 or 3 sets to bring to the dyno. I won't be doing auto height adjustable trumpets anytime soon (maybe never) so i'll just pick a power curve I like and stick with those. That's the plan at least...
noted! Good to know. I have a feeling after probably 10+ years of having exposed headers (albeit most of that time they were coated) I probably fried my compressor. I'll likely put a new one in when the motor goes in.
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I also did it:
Great picture, thanks for this as I will be doing the same in a couple of weeks when my motor gets pulled.
updates
I am so glad you are continuing the fine tuning of your beautiful machine. So looking forward to our cruise to NSXPO 2021 next year. I've got some plans for my car in the next couple of weeks. The joy of NSX ownership.
I am so glad you are continuing the fine tuning of your beautiful machine. So looking forward to our cruise to NSXPO 2021 next year. I've got some plans for my car in the next couple of weeks. The joy of NSX ownership.
@BBVNSX - that's a great job! kudos to you sir. I plan to have the engine out in Q1 next year so I plan to address all these bits and bobs. That list is getting longer!
@Valhalla - I miss seeing your mug old friend! Looking forward to Portland!
Onto more updates! I've been on a roll this week with NSX work. I finally got the car back on the ground. In retrospect I'm glad I went through the headache of performing the header swap. I caught quite a few items that needed addressing (loose bolts, heat shielding, rewiring, re-ziptying, regreasing, parts replacement, etc...). I'll have to go through this entire process again in January when I will have more items to address which will be easier with the engine out.
Updates for now include the install of ceramic coated RFY headers, removed the factory redundant narrow band O2 sensors (I only run 2 widebands now), SOS street cats, and Comptech V2 muffler. Upon first startup I noticed something strange... the amount of exhaust steam/smoke was equally outputted on both exhaust tips. Previously it was favoring the driver's side noticeably. I'm going to check my old HF cats to check for clogging. I can't think of why else this would be. Perhaps it's just my imagination. I also noticed the exhaust smell was so much more tolerable, smells like our stock Lexus warming up, which made me really happy (and made me feel old at the same time). These SOS cats seem to be doing a great job. I hope I don't burn them up during the fine tuning process. My goal with this ITB project is to maintain acceptable tail pipe emissions. I've learned enough about tuning, I think I can get this car to pass CA smog emissions requirements.
I wanted to start the car while the car was still up in the air. This was so I could address any issues that came up like leaks. I spend so much time tuning for these often overlooked conditions like cold start idle quality. I was so proud of myself I had to take a video and posted it on my stories. I grabbed that for your consumption below :biggrin: I recall the early days of learning the HKS F-Con and just learning the basics of tuning in general. It was milestone after milestone. Getting the car to start.. getting it to hold idle.. getting it to blip... and so on.
https://youtu.be/sLC9YDPv_Hc
This is everything nearly wrapped up. Minus the factory braces and what not.
@Valhalla - I miss seeing your mug old friend! Looking forward to Portland!
Onto more updates! I've been on a roll this week with NSX work. I finally got the car back on the ground. In retrospect I'm glad I went through the headache of performing the header swap. I caught quite a few items that needed addressing (loose bolts, heat shielding, rewiring, re-ziptying, regreasing, parts replacement, etc...). I'll have to go through this entire process again in January when I will have more items to address which will be easier with the engine out.
Updates for now include the install of ceramic coated RFY headers, removed the factory redundant narrow band O2 sensors (I only run 2 widebands now), SOS street cats, and Comptech V2 muffler. Upon first startup I noticed something strange... the amount of exhaust steam/smoke was equally outputted on both exhaust tips. Previously it was favoring the driver's side noticeably. I'm going to check my old HF cats to check for clogging. I can't think of why else this would be. Perhaps it's just my imagination. I also noticed the exhaust smell was so much more tolerable, smells like our stock Lexus warming up, which made me really happy (and made me feel old at the same time). These SOS cats seem to be doing a great job. I hope I don't burn them up during the fine tuning process. My goal with this ITB project is to maintain acceptable tail pipe emissions. I've learned enough about tuning, I think I can get this car to pass CA smog emissions requirements.
I wanted to start the car while the car was still up in the air. This was so I could address any issues that came up like leaks. I spend so much time tuning for these often overlooked conditions like cold start idle quality. I was so proud of myself I had to take a video and posted it on my stories. I grabbed that for your consumption below :biggrin: I recall the early days of learning the HKS F-Con and just learning the basics of tuning in general. It was milestone after milestone. Getting the car to start.. getting it to hold idle.. getting it to blip... and so on.
https://youtu.be/sLC9YDPv_Hc
This is everything nearly wrapped up. Minus the factory braces and what not.
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I'm having a lot of fun learning the 3D printing process. I'm still on the basic PLA filament (easiest to print, most compliant), but i'm working my way up to ASA and ABS (both acceptable for basic automotive use) which are much more finicky. These trumpets took 3 days to print using a new carbon fiber infused PLA. It's strong but not as heat tolerant as ABS and ASA. It's good practice and as you can see I'm getting better at calibrating the printer. These look almost good enough to sell, well not really haha. Printer calibration is pretty intuitive to learn but I'm still a long way from 3D CAD design. I had a friend whip up this design in minutes. It would have taken me hours.. maybe days. As soon as I receive some additional parts from [MENTION=20830]A.S. Motorsport[/MENTION]s I'll be visiting the dyno with these trumpets. Ultimate goal is to 3D print a prototype airbox... Hence the curved trumpet which is needed for optimal fitment inside of the airbox.
So cool 
